cinestill film creates photographic film for still cameras from kodak 's motion picture cinema film .

cinestill film uses a modified version of kodak motion picture cinema film , allowing it to be developed with the c-41 process rather than the eastman color negative process .

beta testing of cinestill film 's " 800tungsten xpro c-41 " began in late 2012 , the film is based on kodak 's " vision 3 5219 " motion picture cinema film .

although the " vision 3 5219 " film is normally rated for 500iso , the conversion to c-41 processing allows the film to be rated at 800iso .

cinestill film converts the kodak motion picture cinema film by removing the remjet backing , a separate anti-halation backing used to protect the film in motion picture cameras .

due to the removal of this anti-halation backing , cinestill film exhibits a glowing effect on the image in areas with strong highlights .

in addition to their first product " 800tungsten xpro c-41 " , cinestill film also produces " 50daylight xpro c-41 " from kodak 's " vision3 50d " motion picture cinema film as 135 film .

cinestill

800tungsten high speed color film , 35mm 135 / 36exp . ( iso 800 ) – cinestill film
cinestill is more susceptible to light leaks and static discharge than most other films so care should be taken when handling .
to celebrate the availability of cinestill bwxx , double - x negative film , all black and white film and chemicals from kodak and cinestill are on sale for black friday . so get your stocking stuffers now or stock up for capturing the holidays on classic b & w film , at 10 % to 33 % off the lowest advertised prices .
q : what is the cinestill bwxx black and white film emulsion and how do i get it ? a : cinestill bwxx is eastman kodak double - x 5222 professionally rolled and packaged in 36 exposure cassettes for still photography . it is a high speed , classic black & white film emulsion , with an ei of 250 under daylight and 200 under tungsten lighting .
cinestill has been delivering advanced cinema film technology to still photographers since 2012 and has established itself as a trusted name for film photographers around the world . cinestill works hand - in - hand with current film photography companies to further the production of analog materials . this collaborative approach to manufacturing increases efficiency and sustainability of current resources , resulting in increased stability across the whole analog photography market , from manufacturing to consumption .
our initial release of bwxx was a limited run ( only 2000 rolls available ) that sold out fast due to high demand . we hope to make bwxx a regularly stocked , widely available cinestill film emulsion .
expiration : unexposed cinestill film should be stored in the fridge and shot within 6 months of purchase to achieve optimal results . exposed film should be processed promptly in c - 41 chemicals to preserve latent image latitude and color fidelity . all current productions of cinestill have expiration dates for one year from manufacture date on the packaging . if your film does not have an expiration date it is from early production and is likely age fogged .
expiration : unexposed cinestill film has a 1 year shelf life , and should be stored in the fridge and shot within 6 months of purchase to achieve optimal results . exposed film should be processed promptly in c - 41 chemicals to preserve latent image latitude and color fidelity . all current productions of cinestill have expiration dates for one year from manufacture date on the packaging . if you have alpha production film ( no retail box ) , it should be used before 2018 .
cinestill 50d is an iso 50 / 18° speed daylight balanced ( 5500k ) motion picture emulsion . technology borrowed from from hollywood ' s wunderkind , kodak 50d , prepped and rolled for safe c - 41 standard development as an iso 50 film .
in the past i have been very happy with cinitsill . however the last four rolls i ordered were defective . i sent them to ncps in carlsbad with many other rolls of kodak and fuji c41 . the kodak and fujicolor came back as great negatives and scans , however the cinestill film was all defective . i have sent all my cinestill to ncps in the past with great results , but this batch was obviously bad . i have attached an example of both a good result from the past and the damage film from my last order .
“cinestill 800t is the only film made for still photographers specifically designed for capturing beautiful color images in limited incandescent
tungsten
light . this new high speed color film for still photography is converted to be compatible with any still photo lab processing from the same preferred film stock commonly used by today ' s top directors and cinematographers ; including steven spielberg , wes anderson , wally pfister , martin scorsese , david o . russell , the coen brothers , emmanuel lubezki and many many more . cinestill allows for that same unmatched image quality and cinematic look to be accessed by you ! ”
expiration : the new and improved production of cinestill film now has an extended shelf life , and has been tested for longevity up to 1 . 5 years without base fogging . unexposed film should be stored in the fridge and shot within 6 months of purchase to achieve optimal results . exposed film should be processed promptly in c - 41 chemicals to preserve latent image latitude and color fidelity . all current productions of cinestill will have expiration dates for 18 months from manufacture date on the packaging . if you have alpha production film ( no retail box ) , it should be used before 2018 .
and if you’d like to mix in some color film while warming by the fireplace or in the bright snowy daylight , be sure to add some 800tungsten and 50daylight in 120 or 135 format to take advantage of the free shipping on film orders $ 75 or more . happy holidays ! still silver , - cinestill
one of the greatest aspects of film is its incredible latitude . this is especially true for 800t . from our tests and user feedback , cinestill 800t is best rated at ei ( exposure index ) 800 in tungsten light when processed in standard c - 41 chemistry . though the original stock ( kodak 500t 5219 ) is recommended to be rated at ei 500 in tungsten light , many cinematographers and filmmakers regularly rate this film at 1000 speed with no push , due to this film ' s amazing shadow latitude . regardless , the ideal iso / ei to rate this film at will always be somewhere between 400 and 800 without push processing . but remember , cinestill 800t is designed for c - 41 processing , which causes a slight push in development and results in a denser negative . thus , we have found 800 to be right in the middle of the ideal exposure index range . expect a unique look from cinestill 800tungsten when photographing :
cinestill bwxx is an excellent choice for those looking for a classic film stock to fill the void left by the discontinuation of it ' s wonderful sister films , kodak plus - x and txp320 . recommended development in any black and white film developers . an extensive list of developing times for this film may be found at urltoken & the massive dev chart form urltoken
a : unexposed cinestill film should be stored in the fridge and shot within 6 months or frozen . exposed film should be processed promptly in c - 41 chemicals to preserve latent image latitude and color fidelity . processed films should remain in a cool , dark place . c - 41 process uses some of the most archival chemicals available for photo processing today . there have been no scientific tests for the dye stability of ecn film cross - processed in c - 41 but from our tests on film processed four years ago there is no color degradation or fogging of the magenta dye layer . all current productions of cinestill have expiration dates on the packaging . if your film does not have an expiration date it is from early production and is likely age fogged .
with so many choices currently available , it helps to have some understanding of when a particular film excels . looking at cinestill 800t , it is necessary to understand where this film comes from and what it was originally designed to achieve . cinestill 800t is produced from a kodak motion picture emulsion originally designed for shooting in limited artificial , continuous , incandescent light . this film is known in the motion picture industry as kodak vision 3 5219 , the 3rd generation of tungsten balanced ei 500 color negative motion picture film , and is the standard for movies shot on film in hollywood . 5219 , or
19
as it is commonly referred to , is optimized for a hybrid workflow , ideal for scanning , with literally futuristic features ( from a still photography perspective ) .
until now , cinematographers have been spoiled with film technology for years before still photographers got their hand - me - downs in the form of
new
emulsions . today , cinestill brings the wonders of cinema film technology to the still photographer . now , anyone can use film in the same lighting situations as new blockbuster movies and tv shows such as inception , argo , lincoln , all of the batman movies , django unchained , man of steel , les misérables , the master , the new star track films , the star wars films , all wes anderson ' s films , breaking bad , the walking dead , boardwalk empire , and the list goes on and on and on . no more switching to high iso digital or on camera flash in tungsten lit environments , because cinestill is now available to still photographers worldwide ! ”
36 exp . 135 rolls . great rated iso 200 - 2000 ! can be pushed to 3000 ! cinestill 800tungsten is a unique film for still photographers . this 800 speed tungsten balanced color negative film is prepared from the same motion picture film stock used by top cinematographers around the world . this film is designed for difficult low light tungsten situations and may be used in many different lighting situations to achieve a variety of looks .
for my senior thesis we get assigned a personal project , i chose to photograph the city of philadelphia at night with cinestill 800 . the shots came out better than expected ; the overall look the film gives is amazing . plus the wide dynamic range of the film is great for night shooting . i don ' t think there ' s another option out there for my style of shooting . i look forward to their 120 stock !
120 format color negative . great rated iso 200 - 2000 ! can be pushed over 3000 ! cinestill 800tungsten ( 2nd . generation ) is a unique film for still photographers . this 800 speed tungsten balanced color negative film is prepared from the same gold standard motion picture technology used by top cinematographers around the world . this film is designed for difficult low light tungsten situations and may be used in many different lighting situations to achieve a variety of looks .
we are in the midst of an analog renaissance ! we have seen unprecedented growth and interest in film , from young photographers and those returning to their first love . cinestill ' s primary purpose is to fuel this renaissance by increasing current production of analog photography materials and providing new analog tools for photographers . actively fueling the analog film renaissance , through increased interest in photographic materials and securing the continued production and availability of essential motion picture and still photography materials and services .
a : it is important to note that cinestill is not simply
repackaged
motion picture film . we utilize the same advanced emulsion technology found in motion picture film to create a still photography film which is modified for c - 41 processing . this material is converted to a different format and suitable for c - 41 chemistry . compared to the original motion picture stock , 800t responds with a slightly increased gamma yielding an 800 iso tungsten balanced negative , which is optimized for digital and optical still photography processes .
q : what is different about cinestill 50daylight film ? a : 50daylight is a iso 50 / 18° speed daylight balanced ( 5500k ) motion picture emulsion , prepped and rolled for clean safe c - 41 standard development as an iso 50 film . boasted to be the world’s sharpest and finest grain color film ! it is ideal for shooting in bright light at wide apertures and for producing high resolution , low grain images . the exposure latitude of this film is beyond anything digital and even most other films can hope to achieve .
note : this emulsion was designed to be processed in ecn - 2 chemicals and may still be processed in it ' s native chemistry , resulting in a pulled negative with lower gamma . test results show consistent in standard c - 41 machine processing when compared with ecn - 2 motion picture lab processing performed by professional labs . long term archival stability has not been tested past 5 years . expectations for archival longevity should be somewhere between kodachrome and most c - 41 films but there are no guarantees . we will replace any roll that shows any defect . we do not accept any liability beyond replacement of original film purchased . products & services are provided “as is” with no liability , to the extent as permitted by law ; e . g . under no circumstances will cinestill film or it ' s creators be liable for loss and damages , neither direct nor indirect , consequential loss or damages , business interruption . without limiting the foregoing , the creators of cinestill film´s liability arising with respect to an order will not exceed the total fees paid or payable related to a specific order .
note : this film was designed to be processed in ecn - 2 chemicals and may still be processed in it ' s native chemistry , resulting in a 500 iso pulled negative with lower gamma . test results show consistent in standard c - 41 machine processing when compared with ecn - 2 motion picture lab processing performed by professional labs . long term archival stability has not been tested past 4 years . expectations for archival longevity should be somewhere between kodachrome and most c - 41 films but there are no guarantees . we will replace any roll that shows any defect . we do not accept any liability beyond replacement of original film purchased . products & services are provided “as is” with no liability , to the extent as permitted by law ; e . g . under no circumstances will cinestill film or it ' s creators be liable for loss and damages , neither direct nor indirect , consequential loss or damages , business interruption . without limiting the foregoing , the creators of cinestill film´s liability arising with respect to an order will not exceed the total fees paid or payable related to a specific order .
note : this film was designed to be processed in ecn - 2 chemicals and may still be processed in it ' s native chemistry , resulting in a 500 iso pulled negative with lower gamma . test results show consistent in standard c - 41 machine processing when compared with ecn - 2 motion picture lab processing performed by professional labs . long term archival stability has not been tested past 4 years . expectations for archival longevity should be somewhere between kodachrome and most c - 41 films but there are no guarantees . we will replace any roll that shows manufacturing defect . we do not accept any liability beyond replacement of original film purchased . products & services are provided “as is” with no liability , to the extent as permitted by law ; e . g . under no circumstances will cinestill film or it ' s creators be liable for loss and damages , neither direct nor indirect , consequential loss or damages , business interruption . without limiting the foregoing , the creators of cinestill film´s liability arising with respect to an order will not exceed the total fees paid or payable related to a specific order .
q : how do i rate cinestill 50daylight ? good results can be achieved rating this film anywhere from ei 12 to ei 100 without push processing . this means you can set your camera meter anywhere from iso 12 - 100 and change it mid - roll without special processing and get beautiful results ! no matter how you meter , you will see almost no grain but color , contrast , shadow detail and highlight rendering will be affected by the chosen iso you meter at . if you expose at a lower iso you will get warmer images with greater halation in the highlights .
when shooting in these situations , the resulting effect is referred to as halation . points of light surrounded by darker tones will produce a
red glow
or
halo
around strong highlights . the effect is significantly reduced with medium format film due to the larger negative and shallower depth of field . longer lenses also reduce this effect . while it is worth stating that all film can halate , cinestill is particularly sensitive to this effect , so it is worth remembering when choosing this stock . that being said , some people have used this unique quality to achieve some awesome results !
for years i ' ve wanted a high speed , tungsten balanced stock to use for stills just like i ' ve always had with movie film . now that cinestill 800t is here , i feel like i can confidently abandon my digital cameras . i ' ve even shot this under waning sunlight without correction . it ' s easy to balance in scanning ( so long as you have your own scanner at least ) , although i ' d recommend rating it at 500 iso under sunlight , even without a filter . i like the halation effect but that ' s really a matter of taste .
of tungsten balanced ei 500 color negative motion picture film stock behind cinestill 800tungsten emulsion . it is at the forefront of r & d for film technology , because the movie & tv industry is film ' s # 1 client . the emulsions are optimized for a hybrid workflow , ideal for scanning , with literally futuristic features ( from still photography perspective ) . kodak
borrowed
technology from their motion picture department for the new portra films and ektar . this is nothing new though , as any advances in film technology have gone to the highest bidder ( we ' ve gotten the trickle down in stills ) for some time now .
800 in tungsten light when processed in standard c - 41 chemistry . though the original stock ( kodak 500t 5219 ) is recommended to be rated at ei 500 in tungsten light , many cinematographers and filmmakers regularly rate this film at 1000 speed with no push , due to this film ' s amazing shadow latitude , but the ideal iso / ei to rate this film at will always be somewhere between 400 and 800 without push processing . cinestill 800t is designed c - 41 processing though , which causes a slight push in development , resulting in a more dense negative so we have found 800 to be right in the middle of the ideal exposure index range .
companies which
repackaged
old unused motion picture stock , forced the photographer to send the film back for makeshift motion picture lab processing , and generated a motion picture format negative that was compatible with motion picture printing . there are some advantages found in modern motion picture formats and processing e . g . , anti - halation , antistatic , lubricant backing . however , the curves , lower gamma and base can prove problematic for tradition still imaging standards . cinestill film is motion picture film , which is modified and packaged for standard still photography lab processing . it harnesses the same outstanding performance and aesthetics found in many blockbuster films produced today , plus it is optimized for still photography workflows .
original beta testing for 800t began in late 2012 , but the concept and original development tests began years before , when we first started shooting the amazing kodak vision 3 stock for our own photography . we accomplished this back then by shooting a long - roll , 250 exposure , bulk film back and through developing a special relationship with a local motion picture lab . we did this because of the costly minimum lengths required by motion picture labs , and because the more splicing that occurred , the more the film became damaged and contaminated . we found moderate success with this technique , but the real journey to cinestill began when scores of people began contacting us about how they too could use this wonderful film . “
light leaks , which may not show up on other films , may show up in cinestill due to it ' s extra sensitivity to low light and what is called
light piping
which is where light can travel through the acetate causing light leaks inside or outside of camera . be sure your camera ' s light seals are in good condition and if you have a film check window on the back door of your camera it would be a safe idea to tape it off . the key to avoiding light leaks outside of camera is to first ,
load in subdued light
as directed on the packaging and second , to keep the rolls in their light tight packaging or other light tight container , before and after shooting , whenever possible .
q : why is the speed rating of motion picture camera films given in exposure indices rather than asa or din values ? a : there is no ansi standard to determine the speed of these films . the speed of motion picture camera films and the suggested filtrations are determined on the basis of practical picture tests . suitable safety factors have been included to allow for differences in cameras , variation in lighting , etc . the exposure index values should not be regarded as numbers which express the absolute speed or sensitivity of the film , neither should they be regarded as fixed values which can not be changed if the results of repeated tests indicate the need for such changes . q : when should i push cinestill 800tungsten ? a : we recommend push processing for anything over iso 800 . treat this film as an iso 800 speed film when processing in c - 41 and push process whenever needed up to iso 3200 .
repackaged
motion picture film can not be processed in standard c - 41 film processors due to the remjet backing present on motion picture films , which would contaminate the chemistry and damage both the machine and film inside .
a : an anti - halation layer on the film ' s base that acts as to protect from base scratches , static , and halation of highlights in exposure . it was notably used on kodachrome ( k - 14 process ) originally in still photography .
a : halation is the reflection of bright points of light off of the film base and pressure plate causing a
glow
in the strong highlights on some images . this is most evident when light sources are in focus in the photograph . halation is a common characteristic of classic black and white photography and in some aerial photographic emulsions .
a : 800tungsten is designed for difficult low light tungsten situations . it may be used in many different lighting situations to achieve a variety of looks but due to it ' s cool color balance and halation some situations will have a more stylistic look that may or may not be desirable .
double - x is a classic black and white film stock left relatively unchanged since it ' s release in 1959 for still and motion picture use . some of the movies using the classic eastman double - x film stock ( 5222 ) include : schindler ' s list ( 1993 ) , memento ( 2000 ) , kafka ( 1991 ) , casino royale ( 2006 ) , i ' m not there ( 2007 ) , and many many more .
recommended development in kodak d - 96 developer , but is compatible will all black and white film developers . an extensive list of developing times for this film may be found at
static discharge can show up as blue or red marks on the film caused by advancing or rewinding the film at too great a speed , especially in cool dry environments .
a : this film has latitude ! the iso that one chooses to rate this film is dependent on what the permissible light available is .
if you overexpose it ( 100 or 200 ) it will still retain highlight detail and fine grain . if you underexpose ( up to 2000 ) you will still retain most shadow detail .
so long as the shadow detail is preserved , the negative may be scanned to retain the good color and dynamics .
less prevalent / smoother the more exposure a color negative film receives ( due to overlapping of t - grain technology and the tonal blending of the dye cloud ) .
yes ! be sure to use a cto ( tungsten ) gel on your flash if you are shooting 800t and adjust exposure accordingly .
a : always meter negative film in a way that you are sure the shadow point of your images preserve some detail . highlights can be overexposed by a dozen stops and still be scanned to retain detail . with a handheld incident meter , point your meter away from the main light source and make a minimum exposure reading . with in camera or spot meter take your minimum exposure reading from the darkest tone in your scene . anything exposed under that should be expected to remain void of detail .
“compelled by our love for analogue photography , and never ones to back down from a challenge , we came to the conclusion that we had to find a way to make it usable in standard 135 canisters with standard developing . ”
in order to make this technology accessible for any film photographer ' s workflow , and avoid the need for costly long - roll processing with motion picture labs , we knew we had to make the film compatible with any still photography lab in the world . our task was to take this amazing film stock designed for ecn - 2 motion picture processing , and invent a treatment to refashion it to be safe for standard c - 41 still photography processing . this meant we had to find a way to eliminate the rem - jet layer of motion picture film without contaminating the sensitive emulsion . ok , so here is where we had to get creative . . . early research and development proved that a simple alkali bath , and water jet wash to remove the rem - jet prior to exposure highly contaminated and partially developed the film , while washing out some of the precious antenna dyes . and that the remjet layer would exhaust and contaminate the developer if not removed prior to developing , resulting in a horrible mess and worthless negatives . after years of r & d , tens of thousands of feet of wasted film and thousands of hours of experimentation – efficient and clean “premoval” of the rem - jet layer was achieved ! and the results . . . beyond that of any other films available to still photographers today ! ”
processing these amazing film stocks in standard c - 41 machines was not accessible until the hurdles of rem - jet and continuous long roll processing were overcome . our proprietary
premoval
process makes these motion picture ( ecn - 2 ) emulsions safe for processing in standard photo lab machines and in c - 41 chemistry , with fantastic color and a slightly boosted gamma level , compatible with still photography paper and post production . ”
800tungsten high speed color film , 35mm 135 / 36exp . ( iso 800 )
bwxx ( double - x ) black & white film , 35mm 135 / 36exp . ( iso 250 ) . . .
tmax p3200 tmz 35mm is back ! 35mm 135 / 36exp . ( iso 3200 ) . . .
cs41
color simplified
quart kit for color processing at home . . .
our proprietary
premoval
process makes motion picture film safe to process in standard c - 41 photo lab chemicals or at home . this emulsion is optimized for a hybrid workflow ideal for scanning , and when processed in c - 41 chemistry it can be optically printed on ra - 4 paper . treat this film as a high speed 800 iso film when processing in c - 41 and push process whenever needed up to 3200 iso .
50daylight fine grain color film , 35mm 135 / 36exp . ( iso 50 )
our new and improved proprietary
premoval
process makes motion picture film safe to process in standard c - 41 photo lab chemicals or at home . this emulsion is optimized for a hybrid workflow , ideal for scanning , and when processed in c - 41 chemistry it can be optically printed on ra - 4 paper . treat this film as a 50 iso film when processing in c - 41 and push process whenever needed .
our new and improved proprietary
premoval
process makes motion picture film safe to process in standard c - 41 photo lab chemicals or at home . this emulsion is optimized for a hybrid workflow , ideal for scanning , and when processed in c - 41 chemistry it can be optically printed on ra - 4 paper . treat this film as a high speed 800 iso film when processing in c - 41 and push process whenever needed up to 3200 iso .
finally , a modern monobath solution for modern film photography ! this easy to use solution is not only ideal for beginners interested in developing their film at home for the first time , but will also improve the results of veteran darkroom enthusiasts as well . try it yourself to become a monobath believer ! df96 ships worldwide from urltoken and will also be available through our dealers . visit to our dealers page to find a shop near you or speak with your local shop and ask them to stock it . long live film !
content including intense points of light ( ie . christmas lights or bright windows )
kodak professional t - max p3200 black & white negative film ⁄ 3200tmz is a multi - speed continuous - tone panchromatic black - and - white negative film that combines high to ultra - high film speeds with finer grain than that of other fast black - and - white films . it is especially useful for very fast action ; for dimly lighted scenes where you can’t use flash ; for subjects that require good depth of field combined with fast shutter speeds ; and for handholding telephoto lenses for fast action or in dim light . it is an excellent choice for nighttime photography .
to preorder this reanimated film stock simply add it to your cart from our product page .
“it’s no secret that we’ve been looking for opportunities to expand our portfolio” said dennis olbrich , president – kodak alaris paper , photo chemicals and film . “darkroom photography is making a comeback , and b & w film sales are clearly on a positive trajectory . given these very encouraging market trends , we believe p3200 tmz will be a great addition to our lineup” .
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- / / w3c / / dtd xhtml 1 . 0 strict / / en
urltoken
this item ' s price has dropped . take advantage while the savings lasts !
b & h ; only collects sales tax on orders shipped to addresses in the states of new york and new jersey .
you may be responsible for state and local sales / use taxes when filing your tax returns . please check your local sales tax laws .
high - speed iso 800 / 30° tungsten - balanced movie stock has been packaged and prepared for use in still cameras .
unique
premoval
stage eliminates the rem - jet anti - halation layer to make it suitable for c - 41 processing . processing can also be done with ecn - 2 chemistry without worrying about the rem - jet layer .
a fantastic film for shooting under tungsten and mixed artificial lighting . i ' ve shot through a bunch of this stuff lately and getting my local lab to develop it , scanning it myself has been easy , and i ' m very happy with the results . not only is this film extremely helpful for those shooting under tungsten lighting , but it opens up a whole new world of creativity for those looking to shoot indoors or under the city lights at night . this will have a permanent place in my film fridge , over all a wonderful film to work with , scan and / or print . it also looks great under natural light when metered around iso 400 or 500 . i have been mostly shooting it at box speed , of iso 800 or even 1000 without a push , and the results have been very pleasing for me .
i ' ve used this film for indoor and outdoor shooting , day and night . it performs better than fujifilm 1600 for night time urban photography ( i shot the sf wharf using it ) . i ' ve also shot indoor performances without flash , and used it with an 85a filter for bright daylight photography . the film does react a bit to bright street lights , giving them a distinctive reddish flow and halo , and it is very light sensitive , so load it in the dark . i ' ve shot a dozen rolls , and had great success . it also scans very well .
this film is tungsten balanced so for artificial lights it looks different then what you ' ll get from lets say kodak portra 400 . the film creates this halation from strong light source , and i think this could be a like or dislike situation because at time its eye distracting i think . also this film is not cheap so i ' ll stay away from using it for random street photography . i think this could be a really nice night portrait film though .
there are a few idiots who have said that this is basically portra film . this is incorrect , as portra is a daylight - balanced film , and this is tungsten - balanced . this is kodak 35mm movie film that has been cut and packed into 135 cartridges , but because it is not pre - exposed with frame indices and bar codes , it will not work with automated processing and the frames will not be indexed . keep in mind that tungsten means it was designed to work in conjunction with incandescent cinema lighting , not mercury , sodium , fluorescent , or other incandescent white balances , so don ' t expect consistent results if you aren ' t familiar with the type of lighting you ' re using . electronic flash will look too blue , and you probably won ' t need flash anyway , but it works well with clear or amber - coated flashbulbs . i ' ve gotten exceptional results at night without flash , shooting at 6400 iso . be aware that because the remjet layer is gone , you will see halos around bright spots , so use them to your advantage . when in doubt , it is better to underexpose than to overexpose this film . the purpose of this film is not to make your photographs look like movie stills , but to create unique effects and give you more flexibility when shooting in low - light situations . i would say this is the best high - speed tungsten film currently in production .
i shot this on a pentax me se with the pentax - m 50mm f / 1 . 4 . i metered for iso 1250 and pushed it 2 stops when processed . the results were awesome ! scans really well , too .
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a doob martingale ( also known as a levy martingale ) is a mathematical construction of a stochastic process which approximates a given random variable and has the martingale property with respect to the given filtration .

it may be thought of as the evolving sequence of best approximations to the random variable based on information accumulated up to a certain time .

when analyzing sums , random walks , or other additive functions of independent random variables , one can often apply the central limit theorem , law of large numbers , chernoff 's inequality , chebyshev 's inequality or similar tools .

when analyzing similar objects where the differences are not independent , the main tools are martingales and azuma 's inequality .

doob martingale

within the
usual
terminology every doob martingale is a martingale but not vice versa . the doob martingales are exactly the uniformly integrable martingales .
doob’s martingale inequalities are a consequence of the following inequalities applied to the submartingale .
@ tony clayton : would please give us of your definition of a doob martingale . best regards
every sequence that was termed as a doob ' s martingale , i was able to deduce that it was also a martingale . so here are few of my questions :
theorem ( doob’s maximal inequalities ) let be a filtration on probability space and let be a continuous martingale with respect to the filtration .
i have to apply azouma inequality to a doob martingale . to do this i have to prove that my doob martingale has bounded increments . wikipedia explains a tecnique which could be very useful to me in order to bound increments ( see doob martingale - wikipedia , the free encyclopedia
mcdiarmid ' s inequality
paragraph ) , but i can ' t understand a passage : why if the function f has bounded increments , then the martingale b has bounded increments ? could someone help me to write down a proof ?
filed under : filtrations and processes , stochastic calculus notes — george lowther @ 12 : 00 pm tags : martingale , martingale inequalities , math . pr , stochastic calculus , submartingale
it is correct that doob ' s inequality doesn ' t apply for $ p = 1 $ . in particular a non - negative martingale is bounded in $ l ^ 1 $ but it is not necessarily uniformly integrable ( and hence doob ' s inequality can not be true for $ p = 1 $ ) . the most common technique used in proving a . s . convergence ( and therefore also $ l ^ 1 $ convergence ) of a martingale is doob ' s upcrossing inequality .
example of adapted process that is a martingale w . r . t to one filtration but not another
then , doob’s inequalities bound the distribution of the maximum of a martingale by the - norm of its terminal value , and bound the - norm of its maximum by the - norm of its terminal value for all .
doob decomposition of $ | s _ n | $ where $ s _ n $ is simple random walk .
martingale inequalities are an important subject in the study of stochastic processes . the subject of this post is doob’s inequalities which bound the distribution of the maximum value of a martingale in terms of its terminal distribution , and is a consequence of the optional sampling theorem . we work with respect to a filtered probability space . the absolute maximum process of a martingale is denoted by . for any real number , the - norm of a random variable is
now , if , we consider for , the stopping time . by using the above result to the martingale , we obtain
with the usual convention that . it is seen that is an almost surely bounded stopping time . therefore , from the doob’s stopping theorem
sorry , i thought of the inequality of moments which only holds for $ p > 1 $ . just disregard my comment . also you could type up these definitions of doob ' s inequality and doob ' s decomposition theorem in your question . it makes it much easier to read : )
maybe it is not clear enough . i know that to prove the $ l ^ p $ , $ p > 1 $ , convergence of a martingale , we can use doob ' s inequality in $ l ^ p $ form . however , it seems in the proof of convergence in $ l ^ 1 $ , that doob ' s inequality is not used ( as far as i understand , it is not enough - we need uniformly integrability ) .
lecture 18 : examples of martingales . doob ' s martingale . method of bounded differences ( mcdiarmid ' s inequality ) . applications to chernoff bounds , and balls - bins . vertex exposure and edge exposure martingales . concentration of chromatic number of g ( n , p ) ( shamir - spencer theorem ) .
there are several formly analogous inequalities in probability theory , for example , komolgorov ' s inequality , doob ' s inequality , and an analogous doob ' s inequality in ergodic theory . they all estimate the probability or expectation of a random variable , $ | x _ n | > m $ where $ m $ is a constant . why are they useful ?
here for an integrable r . v . $ x $ and a filtration $ ( \ mathcal { f } _ t ) _ { t \ in t } $ the corresponding doob martingale $ d _ t $ is defined via $ d _ t : = e ( x | \ mathcal { f } _ t ) , t \ in t $ .
i ' m working on my first ever proof that a stochastic process is a martingale , and i ' m a bit confused . is there a
standard machine
for these proofs ?
a doob martingale is a generic construction that is always a martingale . specifically , consider any set of random variables $ $ \ vec { x } = x _ 1 , x _ 2 , . . . , x _ n $ $ taking values in a set $ a $ for which we are interested in the function $ f : a ^ n \ to \ bbb { r } $ and define : $ $ b _ i = e _ { x _ { i + 1 } , x _ { i + 2 } , . . . , x _ { n } } [ f ( \ vec { x } ) | x _ { 1 } , x _ { 2 } , . . . x _ { i } ] $ $ it is possible to show that $ b _ i $ is always a martingale regardless of the properties of $ x _ i $ . the sequence $ \ { b _ i \ } $ is the doob martigale for $ f $ .
for the second question , in durrett ' s book , it says that doobs decomposition is usefull in reducing questions about submartingales to questions about martingales . as far as i understand , if there is a question about submartingale , we can consider to use decomposition to transfer it to a problem on martingale .
about 3 , well for countable extensions you need at least an infinite dimensional function $ f $ of course ( or a fonctional for the uncountable case ) , this is also motivated by my answer to point 1 . at the moment i can ' t see a sufficient condition to give a real meaning to doob ' s martingale in that context , but i feel that uniform integrability condition over the $ x _ i $ would probably be usefull to get limits more easily , but this by no way mandatory i think . if i can figure out an extension formally satisfactory i ' ll edit the answer accordingly .
to be more specific , i am trying to show that if $ y $ is a random variable with $ e ( y ) < \ infty $ , the process $ x _ n = e ( y | i _ n ) $ is a martingale ( where $ i _ n $ is an arbitrary filtration ) .
doob ' s inequality : let $ x $ be a submartingale taking on non - negative real values , that is , for all times $ s $ and $ t $ with $ s < t $ , $ e [ x _ t \ mid \ mathcal f _ s ] \ geq x _ s $ . then , for any constant $ c > 0 $ and $ t > 0 $ we have
what i mean doob ' s inequality in l1 is following : let x be a submartingale taking non - negative real values , that is , for all times s and t with s < t , $ \ mathbf { e } \ big [ x _ { t } \ big | \ mathcal { f } _ { s } \ big ] \ geq x _ { s } . $ then , for any constant c > 0 , $ \ mathbf { p } \ left [ \ sup _ { 0 \ leq t \ leq t } x _ { t } \ geq c \ right ] \ leq \ frac { \ mathbf { e } \ big [ x _ { t } \ big ] } { c } $ .
@ tim : the notation $ e _ { ( x _ { i + 1 , . . . , x _ n ) } } $ is really misleading or confusing in my opinion ( for example consider such notation in the context of a brownian motion it is really disturbing isn ' t it ) . the proof of the fact that $ b _ i $ is martingale with respect to $ \ mathcal { f } _ i = \ sigma ( x _ 1 , . . . , x _ i ) $ is clear from the proof of lemma 2 ( which just the very well known tower property of iterated conditional expectations ) in the document of anupam gupta given as reference on wiki ' s page . i shall try to answer your question later on .
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$ e ( x _ n | i _ m ) = x _ m $ for $ m < n $ .
i can do condition 2 easily enough , by substituting $ x _ n = e ( y | i _ n ) $ and using the tower property .
$ $ e ( x _ n | i _ m ) = e ( e ( y | i _ n ) | i _ m ) \ stackrel { ? } { = } e ( y | i _ m ) = x _ m . $ $
$ e ( e ( y | i _ n ) | i _ m ) = e ( y | i _ m ) $ holds because of the law of iterated expectations , for which $ e ( e ( y | i _ n ) ) = e ( y ) $ is just a special case .
it might also help to specify what exactly is $ i _ n $ in your question .
here ' s a somewhat expanded answer , since this is a fairly straightforward question if you ' ve covered the relevant definitions .
let $ m < n $ , then we have that $ \ mathbb { e } ( x _ n | i _ m ) = \ mathbb { e } ( \ mathbb { e } ( y | i _ n ) | i _ m ) $ . but from the definition of a filtration , we know that $ i _ m \ subseteq i _ n $ , so the law of iterated expectations applies , and it follows that $ \ mathbb { e } ( \ mathbb { e } ( y | i _ n ) | i _ m ) = \ mathbb { e } ( y | i _ m ) = x _ m $ , which proves 3 .
you already know that $ \ mathbb { e } ( x _ n ) = \ mathbb { e } ( \ mathbb { e } ( y | i _ n ) ) = \ mathbb { e } ( y ) < \ infty $ ; as i remarked , this is a special case of the law of iterated expectations .
it remains to show that the stochastic process $ ( x _ n ) _ n $ is adapted to the filtration $ ( i _ n ) _ n $ . that means we want to show that for each $ n $ , $ x _ n = \ mathbb { e } ( y | i _ n ) $ is an $ i _ n $ - measurable random variable . depending on what your definition of the conditional expectation is , the fact that $ \ mathbb { e } ( y | i _ n ) $ is measurable with respect to $ i _ n $ was either part of the definition itself , or should have been one of the first properties you proved once you defined it .
thank you . see , that ' s where i was getting stuck . i ' m using a mish - mash of texts , and i don ' t have a single clear definition of conditional expectations ( so it gets confusing when responsibilities
shift
)
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$ $ \ lim _ { k \ to \ infty } \ sup _ { t \ in t } e ( | x _ t | \ , 1 _ { | x _ t | > k } ) = 0 . $ $
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let and . if then , from jensen’s inequality the process is a submartingale . let and
hi , professor baudoin . i think in the first line of the proof of the part 2 , it should be p > 1 .
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the second statement above does not generalize to and , in fact , there exist martingales such that the maximum has infinite expectation at all positive times .
proof : by completing the filtration if necessary , without loss of generality we assume that it is complete . consider the first time at which the process reaches the positive value ,
which , by the debut theorem , is a stopping time . then whenever and , in particular , . optional sampling gives
bounding the right hand side above by gives the first inequality . multiply by and integrate up to some limit to get ,
finally , cancel from both sides and take the limit to get the second inequality in the statement of the theorem . ⬜
just a small comment : i think one needs to first consider a finite time grid to be able to assume that { x _ t ^ * > = k } = { \ tau < = t } ( second line in proof of theorem 2 ) and the use mct to get the result for countable time and continuous time in the cadlag case , like you mentioned in the planetmath proof .
hi . you can do it that way , but it is not necessary to start by restricting to the finite case . i already proved the debut theorem and optional sampling for continuous - time cadlag processes . as we assume the process is cadlag , these can be applied directly to the continuous time case .
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i am working on a research problem in uncertainty propagation that involves sums of possibly dependent random variables with bounded sets of support . i am attempting to use the method of bounded differences as an amateur . in general , most presentations of this method promise to handle arbitrary dependences between random variables but all worked out examples involve independent random variables .
$ $ x _ 0 = \ left \ { \ begin { array } { cc } 1 & \ mbox { with probability } \ \ frac { 1 } { 2 } \ \ - 1 & \ mbox { with probability } \ \ frac { 1 } { 2 } \ \ \ end { array } \ right . \ , , $ $
and $ x _ { i + 1 } = x _ i $ for $ i \ geq 0 $ . in other words , $ x _ i $ s for $ i \ geq 1 $ are
very highly correlated
with $ x _ 0 $ . : - )
we are looking at $ \ sum _ { i = 0 } ^ n x _ i $ and with probability $ \ frac { 1 } { 2 } $ each it can be either $ \ pm ( n + 1 ) $ .
$ $ y _ i = \ mathbb { e } \ left ( \ sum _ { j = 0 } ^ n x _ j \ | \ x _ 0 , \ ldots , x _ { i - 1 } \ right ) \ , . $ $
we can show that $ $ | y _ { i + 1 } - y _ i | \ leq 1 \ , . $ $
clearly i am wrong ! this is the same as the chernoff hoeffding bound for the iid case ! i am wondering where i went wrong . very grateful for your help !
[ 1 ] dubhashi and panconesi , concentration of measure for the analysis of randomized algorithms .
resolution : it seems to be resolved thanks to the comments below from @ alpoge . the mistake here is $ y _ 0 = \ mathbb { e } ( \ sum x _ i ) = 0 $ . but $ y _ 1 = y _ 2 = \ cdots = y _ n = ( n + 1 ) x _ 0 $ and therefore , when applying azuma ' s theorem , the denominator will be something like
now the bounds obtained are much weaker and consistent with having $ y _ n $ being $ n + 1 $ with probability $ \ frac { 1 } { 2 } $ and $ - ( n + 1 ) $ with probability $ \ frac { 1 } { 2 } $ .
the lesson is then when the method of bounded difference is applied to sums of dependent random variables , care should be taken to calculate $ \ mathbb { e } ( x _ j | x _ 0 , \ ldots , x _ { j - 1 } ) $ carefully when $ x _ { j } $ could be dependent on $ x _ 0 , \ ldots , x _ { j - 1 } $ . it is tempting to equate this to $ \ mathbb { e } ( x _ j ) $ .
azuma gives you a bound on the probability that y _ n - y _ 0 is large , no ? ( here it ' s 0 . )
not quite , $ y _ 0 = 0 $ and $ y _ n = ( n + 1 ) x _ 0 $ right ? but between your previous comment that you just modified , and edgar ' s comment below , i think i can see a mistake . $ y _ 1 $ is already $ ( n + 1 ) x _ 0 $ . so the difference $ | y _ { i } - y _ { i - 1 } | = 0 $ for $ i \ geq 2 $ but $ | y _ { 1 } - y _ { 0 } | = 2 ( n + 1 ) $ . the result will be different . is that the mistake ?
sorry , i keep indexing wrong ! yeah it ' s as i said in the comment i deleted - - - the bound on the increments doesn ' t hold for y _ 1 - y _ 0 . the general bound is prob . ( y _ k - y _ 0 \ geq t ) \ leq \ exp ( - t ^ 2 / ( 2 \ sum _ { i = 1 } ^ k | | y _ i - y _ { i - 1 } | | _ \ infty ^ 2 ) ) . applying this you get a denominator that is order n ^ 2 , rather than order n .
( i ' m certainly no expert so the bound above is probably not optimal - - - e . g . the constant in the exponential is probably suboptimal . )
if you would like , please add a solution . otherwise , i have added a resolution to my post . thanks once again ! the nice thing is that this gives the same answer as another paper i am reading by jansen that uses the chromatic number of the dependence graph . so i am much happier !
what if we work it out ? all of $ x _ j $ are equal to $ x _ 0 $ , in particular measurable with respect to $ x _ 0 $ . so $ $ \ sum _ { i = 0 } ^ n x _ i = ( n + 1 ) x _ 0 , \ \ y _ i = ( n + 1 ) x _ 0 \ qquad \ text { for all } i \ \ y _ { i + 1 } - y _ i = 0 $ $ certainly bounded differences . . .
thanks ! i am actually translating a much more complicated situation into a
toy problem
that i have posted . in general , there are no other hypotheses . i still do not see where i went wrong .
except that $ y _ 0 $ is not $ ( n + 1 ) x _ 0 $ , it is the constant 0 . now apply azuma ' s theorem using all the differences including the very large difference $ | y _ 1 - y _ 0 | $ . ( this is much the same as alpoge ' s comment above . )
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can the set of random variables $ \ { x _ 1 , x _ 2 , . . . , x _ n \ } $ be generalized from finite to infinite ( countably or uncountably ) ?
about 1 , yes $ f $ is clearly part of the definition of $ b _ i $ .
about 2 , a requirement could be for $ f ( x _ 1 , . . . , x _ n ) $ to be an integrable random variable with respect to the joint law of $ ( x _ 1 , . . . , x _ n ) $ , alternatively you can suppose that $ f $ is either positive ( or negative ) or bounded , what is important is that the conditional expectation involved make sense at every steps .
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$ $ \ mathbf { p } \ left [ \ sup _ { 0 \ leq t \ leq t } x _ { t } \ geq c \ right ] \ leq \ frac { \ mathbf { e } \ big [ x _ { t } \ big ] } { c } . $ $
$ $ \ | x _ { t } \ | _ { p } \ leq \ | s _ { t } \ | _ { p } \ leq \ frac { p } { p - 1 } \ | x _ { t } \ | _ { p } . $ $
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lecture 1 : upper bound and lower bound for ramsey numbers . probabilistic and deterministic approximation for max - cut .
lecture 2 : bollobas ' s theorem . sum - free sets . property - b ( lower bound ) . dominating sets in graphs with large min - degree .
lecture 3 : property b ( upper bound ) . coloring non - linear hypergraphs . dominating sets in graphs of high min - degree ( probabilistic and algorithmic version ) .
lecture 4 : tournaments with property s _ k . maximum number of hamiltonian paths in a tournament ( lower bound ) . local - vs - global satisfiability . balancing vectors .
lecture 5 : sperner ' s theorem . turan and ramsey using the deletion method .
lecture 6 : gilbert - vershamov bound ( greedy and probabilistic constructions ) . approximate sum of binomial coefficients . turan ' s theorem . high girth and high chromatic number .
lecture 7 : maximum number of hamiltonian paths in a tournament ( upper bound ) . erdos - ko - rado theorem .
lecture 8 : hardy - ramanujan theorem . distinct sums . g ( n , p ) threshold for isolated vertices .
lecture 9 : g ( n , p ) threshold for connectivity and for appearance of k _ 4 .
lecture 10 : solution of home assignments . 2 - point concentration of clique - number of g ( n , p ) .
lecture 11 : arithmetic progressions in quasi - random integer sets . chernoff bound ( special case ) .
lecture 13 : bennett / bernstein inequality . consistent arcs in tournaments . lower bound for relaxed ramsey problem . improved lower bound for property b .
lecture 14 : applications of the the lovasz local lemma . property b . cycles in directed graphs . non - repetative strings .
lecture 15 : proof of local lemma . improved bound for r ( 3 , k ) . independent transversals .
lecture 16 : four functions ( ahlswede - daykin ) theorem . kleitman ' s lemma . fkg inequality . correlated events in random graphs .
lecture 17 : marica - schonheim theorem . chebyshev ' s association inequality . azuma ' s inequality .
lecture 19 : the chromatic number of g ( n , 1 / 2 ) ( bollobas ' s theorem ) . an isoperimetric inequality on the hamming cube .
lecture 20 : 4 - point concentration for the chromatic number of sparse random graphs . local - vs - global coloring ( erdos ' s theorem ) . tsp in the unit square ( deterministic upper bound ) .
lecture 21 : near gaussian tail for stochastic tsp via method of bounded average differences . choice number of g ( n , 1 / 2 )
lecture 22 : janson ' s inequalities . triangles in sparse random graphs . chromatic number of g ( n , 1 / 2 ) via janson .
lecture 23 : diameter of random graphs via janson ' s inequality . method of non - uniform bounded differences using talagrand ' s inequality . gaussian tail for stochastic tsp . improved bound for balls - bins .
lecture 24 : concentration around median vs expectation . concentration of certifiable functions using talagrand ' s inequality . concentration of longets increasing subsequence .