HDTenEightyP/NetNews huggingface dataset:
From: gsnow@clark.edu (Gary Snow)
Newsgroups: rec.photo
Subject: Re: How to make a good ghost illusion?
Keywords: Ghost, multiple exposure
Date: 15 Oct 92 20:31:30 GMT
Article-I.D.: clark.1992Oct15.203130.1379
Organization: Clark College, Vancouver, Wa.  USA

In article <20479@fritz.filenet.com> daver@fritz.filenet.com (Dave Richards) writes:
>
>The degree of ghost effect is controlled by the relative intensity of
>the "ghost" illumination to the background.  Obviously, you are shooting
>the background through the glass, and the reflection of the "ghost" from
>the surface of the glass.  As a result, the ghost image will be a mirror 
>image, which may have to be taken into account.  The light absorber be-
>hind the ghost subject on the right is to make sure the ghost is the only
>image reflected from that direction.  You don't want unwanted ghost objects
>showing up.  The light absorber on the left is probably optional.  Without
>it, there is a possibility of background highlights reflecting off the
>back side of the glass, then off the left wall (if it's light colored)
>and then back onto the wall as well as the ghost subject.  This could
>create a mottled appearance.

Pardon my question, but what do you focus on, the background behind the
glass plate, or the reflected image from the glass plate.

Gary

-- 
-----
Gary Snow
uunet!clark!gsnow  or  gsnow@clark.edu
From: ka1gt@cbnewsm.cb.att.com (robert.m.atkins)
Newsgroups: rec.photo
Subject: Reciprocity failure (was Re: moonlit landscapes / stars (4x5)
Date: 16 Oct 92 17:04:16 GMT
Article-I.D.: cbnewsm.1992Oct16.170416.3773
Distribution: na
Organization: AT&T

In article <1992Oct16.093359.1@vms.ocom.okstate.edu>, chorley@vms.ocom.okstate.edu writes:
> 	With reciprocity failure on colour films: do the three colours show 
> equal amounts of failure, is it unpredictable/inconsistent or what?
> 
For long exposures (more than 1 second) color films show a color shift which
depends on the length of the exposure and the film type. Each film has a
consistant color shift, but all different types of film are different.
For example, Fujichrome Velvia needs +2/3 stop +10M correction @ 16secs.
             Fujichrome 400    needs +1/2 stop +2.5Y correction @ 16secs.
             Kodachrome 64     needs +1 stop  +10R correction @ 1 second.

Most manufacturers publish reciprocity correction factors for their films,
but only up to about 10 seconds for most films (longer for tungsten light
films). Note that you can reduce the reciprocity failure (as least as far
as exposure time goes) by soaking a film in warm, dry hydrogen (better yet
forming gas) for several hours. This is "hypersensetisation" and is
commonly used in astrophotography (where exposure may stretch to hours).

===============================================================
Bob Atkins  AT&T Bell Labs  email (direct)  att!clockwise!rma
===============================================================
Newsgroups: rec.photo
From: zrepachol@cc.curtin.edu.au (Paul Repacholi)
Subject: Re: invisible flash?
Organization: Curtin University of Technology
Date: Sat, 10 Oct 1992 19:58:26 GMT

In article <7030008@hpunila.MSR.HP.COM>, rkatos@hpunila.MSR.HP.COM (Ray Katos) writes:
>>----------
> Buy a roll of kodak infra-red.  It says to use a wratten 87 filter over the
> flash..inhibits all visible light. Further, it tells of the probabilistic
> nature of infra-red: light meters for photography are not calibrated for
> infra-red.  Go run some experiments and let us know!

yeah, but make sure the bride isn't is a light white nylon bridal gown, or the
groom may want to do some experiments on you... Or pay for the photos. PS, you
mentioned fine grain... not with IR.
Have fun

~Paul
From: dleong@casbah.acns.nwu.edu (Leong Dennis)
Newsgroups: rec.photo
Subject: Tokina 2x Teleconverter for sale
Keywords: night, moon, stars, 4x5, view camera
Date: 15 Oct 92 01:25:47 GMT
Article-I.D.: news.1992Oct15.012547.6989
Organization: Northwestern University, Evanston Illinois.


I have an almost-brand new Tokina  manual 2x teleconverter (7 elements) for sale.  Bought it
one month ago for $64.95 and will let go for $50.  Got it for my New England
trip and used it only once.  Will have no more use for it in future.  

Those interested can e-mail me and make arrangements for delivery.

Thank you.
Dennis
From: kbarger@cellar.org (Kyle Barger)
Newsgroups: rec.photo
Subject: Stereoscopic pictures
Date: 16 Oct 92 02:29:33 GMT
Organization: The Cellar BBS and public access system

I've always been interested in 3-d photography, and so when I saw a book of
stereographs in a bookstore, I had to buy it.  (The book was "The
Stereoscopic Nude, 1850-1930" by Serge Nazarieff.  You'll have to take my
word that I bought it because it was in stereo.  :-)

My question is, can anybody recommend any other collections of stereograms? 
I'd also be interested in histories, of the subject, but mainly I want more
pictures.  


--------------------------------------------------------------------------
Kyle Barger                     "Beauty, alas, is not relevant to Usenet."
kbarger@cellar.org      --Brendan Kehoe, _Zen and the Art of the Internet_
--------------------------------------------------------------------------
Newsgroups: rec.photo
From: rjansen@nyx.cs.du.edu (Robert Jansen)
Subject: Coming to America (San Francisco)
Organization: Nyx, Public Access Unix @ U. of Denver Math/CS dept.
Distribution: usa
Date: Wed, 14 Oct 92 19:01:19 GMT



Hi all.
I'm visiting the Interop (exhibition 'bout computer networks) Fall '92
exhibition in San Francisco.
I would greatly appreciate Iif anybody could give me a pointer were to
buy a new camera in San Francisco. (i.e. Low prices prefered !)
I'm very interested in the Nikon F90 with an AF nikkor 35-70 D lens.
(In europe it's called the F90, but after reading al the articles in this
group, I guess it's exactly the same as the  N90 in the states)
(If so, It would give me a price difference of 'bout $420 !!)
Even the Sharp electronic organizer which you can hook up to the F(N)90 has
a different name.
Please email me at  rjansen@vnet3.vub.ac.be, because at this adress I can
receive my mail at home.
I'm leaving the 22nd  this month, but you can still reply till the 30th.
(I can read my mail at the exhibition, because they have internet access)
Thanks in advance.
Robert Jansen (Network management of the University of Brussels)
  rjansen@vnet3.vub.ac.be

Greetings From Belgium (Europe) land of gourmet beer, chocolates and
Brussels sprouts. :)

Robert
----------
 hushsig included :)
h
From: russell@Apple.COM (Russell Williams)
Newsgroups: rec.photo
Subject: Re: minolta xi lenses
Date: 14 Oct 92 01:25:39 GMT
Organization: Apple Computer Inc., Cupertino, CA

In article <73316@apple.Apple.COM> chuq@Apple.COM (Chuq Von Rospach) writes:
>yw1@Ra.MsState.Edu (Yin Wang) writes:
>
>>	I bought a minolta 9xi from a mail order shop. When I also placed ordersfor two minolta xi series lenses (xi 28-80 f3.5 & xi 80-200 f4.5), the salesman
>>told me the minolta xi lenses have problem in manuel focusing and the lenses
>>are slow and the quality of lense optics are not good. So he suggest me to buy
>>a set of Tokino lenses (AF 28-70 f2.8 & 70-210 f4.0). He said these two lenses
>>are high quality and fast. The only thing I am loose he said is the power zoom
>>and widerview features provided by xi camaras.
>

The other difference is that because the zoom control is motorized, it's
a rate control instead of a position control. That is, with a normal zoom,
the position of the zoom ring directly controls the lens focal length.
With an xi (or other power zoom lens), the position of the zoom ring
controls how fast the focal length changes. It doesn't matter to some
people; I hate it. I have a 7xi and a 9xi and would never consider an
xi lens.

>helped your picture quality. Adding 25% to the cost of the lenses for what
>is effectively one stop faster glasses is a questionable deal (you could

25% for 1 stop is cheap -- the next stop will cost you a LOT more
(check out the prices for 70-210 or 80-300 f/2.8s). How the quality
of these specific lenses compare, I don't know. In general,
the big independent lens makers are quite competitive on price for
optical quality in a given speed and lens size / weight. As for 
whether the extra stop is worth the money
to you, only you can decide. It costs you weight and size as well.
The lenses you bought are in the general range of price / speed / quality
tradeoffs I choose; that doesn't mean they're necessarily the right 
choices for you. 
-- 
Russell Williams
Not speaking for Apple Computer
Organization: Arizona State University
Date: Monday, 12 Oct 1992 18:43:36 MST
From: <IACRPM@ASUACAD.BITNET>
Newsgroups: rec.photo
Subject: Re: How does solarization work?
Distribution: rec
 <92282.125308ACPS7035@RyeVm.Ryerson.Ca>

A semantical quibble, but solarization is the reversal of tones due to
gross overexposure--e.g., the sun appearing as a small, black disk.
Solarization is fairly uncommon with modern materials.

The reversal of tones during processing is the Sabbatier effect.  Stieglitz
put this to good use in a portrait of O'Keeffe; it's so subtle that you're
not aware at first that the tones are reversed, as the flesh tones are
normal.  But you'll notice the think black line outlining the area between
her body and the areas that have been reversed--the Mackie line.  It
underscores the contours of her body.

The best thing about your using a flash as the light source as it's
considerably more controlled that flipping the overhead light on and
off real fast...
From: savoia@sw.stratus.com (Rick Savoia)
Newsgroups: rec.photo
Subject: The Faster Slide films
Date: 15 Oct 92 18:56:29 GMT
Distribution: usa
Organization: Stratus Computer, Inc.



A friend is looking for a fast slide film.  He enjoys
shooting with Kodak Gold 1600 now, but he would rather
use slide film.  The best he's found in slide is
Ektachrome 400x.  Does anyone know of any faster slide
films.  I tend to the slower films so I haven't been
paying attention to the faster ones!  

He enjoys shooting with longer lenses in situations
where setting up a tripod isn't always easy.  If 
anyone has any suggestions, please reply to 
David_Benton@vos.stratus.com.  He does not read this
newsgroup, so please use email.

Thanks,

Rick

-- 
==========================================================
Rick Savoia                     | "I'm just very selective
savoia@watts.sqa.stratus.com    | about the reality 
Rick_Savoia@vos.stratus.com     | I accept" - Calvin
==========================================================
Newsgroups: rec.photo
From: eugene@briar.lle.rochester.edu (Eugene Kowaluk)
Subject: Freezing Film
Organization: UofR Laboratory for Laser Energetics
Date: Thu, 8 Oct 92 13:31:17 GMT


Rick Ellis writes:
> On <Oct 06 12:31> Jim Hood writes:
> 
>  JH> I was always taught that the freezing process caused some of the 
>  JH> chemicles in the emultion to expand as it crystalizes (as water 
>  JH> does), and that this pushes the silver around and such.  The more 
>  JH> your freeze your film the grainer picture.
> 
> Sounds like somebody's speculation.  Anybody have some real test results?


As I posted not too long ago, my experience has been with more sensitive
(& more expensive) emulsions such as HSIR or spectroscopic films.  If either of
these films sits in an air-conditioned darkroom for more than one year,
they will degrade to a point where they are useless.

My frozen and refrozen HSIR 8x10 sheets have only degraded 0.1 +/- 0.04 in
the past five years.  Of course, I encapsulate them in a vapor barrier
even if they were in the original container.

As to emulsion expansion due to crystalization, I don't have exact data
but just observations of more than several hundred sheets of film that I've
digitized using the 50X magnification on my microdensitomer.  The grain being
so course compared to the T-grain films, is easily viewed and can not be
distinguished from newly purchased 4x5 sheets and 35mm (with thinner base).
I can only guess that any emulsion degradation is due to the lack of proper
encapsulation.

It's a tradeoff between having enough film on hand for use and refreezing
them, and discarding film for fear of refreezing it.  The latter is obviously
more expensive, especially with Kodak discontinuing several of our more
exotic films and increasing the prices of minimum orders.

If you have fears of hurting your films through refreezing, then just buy
enough for a shoot.  Otherwise, just stay with the "non-pro" films which
have a long shelf life.


eugene kowaluk
Newsgroups: rec.photo
From: elau@berlioz.nsc.com (Eugene Lau)
Subject: mail order experience
Organization: National Semiconductor Corporation
Distribution: na
Date: Mon, 12 Oct 1992 21:52:56 GMT

I ordered several items about a week ago.  a tamrac bag, a tripod, and a tripod
quick release adaptor, from camera world of oregon - no problem, got here in 
3 days (california).  I ordered some cheap and small items from Porter's, they
arrived within one week, no problems.  I wanted to return some of Porter's 
items (didn't want them anymore), and their customer service rep was friendly.
then I ordered a light box, a flash diffuser, and film from B&H, no problems 
again.  the film was fujichrome 100 (RD 135), and $6.30 got me USA film 
including processing. 

all three vendors were good.  now, on to the problem.  I called adorama before
calling CWO and B&H.  They didn't carry the first three items on my list, and
before I can go on to tell them the fourth item, the guy hung up on me.  I 
believe his name was Mitch, and I also believe I'll never call adorama again.

in summary: no problem vote for Camera World, Porter's, and B&H.  minor hassle
            vote for Adorama.

will the survey keeper please tally this vote, thank you.

eugene
From: johno@sdd.hp.com (John Ongtooguk)
Newsgroups: rec.photo
Subject: Re: empty film canisters
Date: 15 Oct 1992 18:34:59 GMT
Organization: Hewlett-Packard, San Diego Division
Distribution: world
NNTP-Posting-Host: hpsdlg10.sdd.hp.com

In article <1992Oct15.161617.26483@informix.com>, bobd@jupiter.informix.com (Bob Dodge) writes:
|> 
|>These are also handy for carrying peanut butter, which seems to attract 
|> birds and animals, in the field. 

  I've also used them for:

  1. Telescope collimation tools; cut off the bottom half of the can
     and carefully punch a small hole thru the gate in the center of
     the can. They fit 1.25in focusers well.

  2. Dummy D cell battery packs; if I was too lazy to take apart an
     item to put in a jack for use with an AC transformer I would put
     the connector in the dummy assembly and drill a small hole in 
     battery cover for access to the jack. 

  3. Mixing small cocktails of paint, solvents, lubricants and such.

  4. Projector screen alignment tool; I wrap about 20 feet of string
     around a can and keep it with the projector. To use it unwind
     the string, loop the string and can around the projector lens 
     and see if the distance to the corners of the screen is the same.
       
  5. Adjustable weights; with a string thru the center of the lid and
     some buckshot or whatever you can easily vary the weight.

  6. Small part containers. 

  John Ongtooguk (johno@sdd.hp.com)
From: monson@hobo.ECE.ORST.EDU (Ty Monson)
Newsgroups: rec.photo
Subject: Re: moonlit landscapes / stars (4x5)
Keywords: night, moon, stars, 4x5, view camera
Date: 15 Oct 92 21:47:28 GMT
Distribution: na
Organization: ECE Dept.,OSU,Corvallis

In article <1992Oct15.200310.6275@cbnewsm.cb.att.com> ka1gt@cbnewsm.cb.att.com (robert.m.atkins) writes:
>In article <1992Oct15.011901.9934@beaver.cs.washington.edu>, franz@cs.washington.edu (Franz G. Amador) writes:
>> Does anyone know a good way to pick an exposure for a moonlit
>> landscape?  Seems like there ought to be a rule equivalent to "sunny
>> f/16" for the full moon; the half moon ought to be one stop darker;
>> etc.  I doubt my light meter will work; it reads only to EV 1 (ISO
>> 100).
>> 
>
>I can tell you that the brightness (luminance) of the sun is
>1.4E5 Candle/sq.cm, and that of the moon is 5.5E-1 Candle/sq.cm.
>The illuminance is the quantity you want (I think) and since the sun
>and moon are similar in size illuminance would scale with brightness,
>giving a ratio of 250000. If this is right, it would mean that you would
>have to open up 18 stops from your sun reading to get correct exposure
>for the (full) moon. Reciprocity failure is going to come in here, so maybe
>20 stops might be better? That would mean that a 1/50 sec at f16 in
>bright sunlight (Velvia) would become about 10 minutes at f2.8 under bright
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>moonlight. These are theoretical numbers - I have no experience in
>moonlight photography!
>
  
  This is really quite a reasonable starting point.
  As supplemental information:
  I have used 20 minutes at f/4 with Kodachrome 64
  Another photographer told me he likes 15 minutes at f/8 with
  Ektachrome 200.
>Bob Atkins  AT&T Bell Labs  email (direct)  att!clockwise!rma

-Ty Monson
From: 739chan1@gw.wmich.edu
Newsgroups: rec.photo
Subject: Yashica -> Nikon lens converter
Date: 9 Oct 92 01:10:12 EST
Organization: Western Michigan University

I am currently using a Yashica FX-3 2000. I also have various screw-mount    
lenses. I managed to purchase a converter so that I could fit the screw-mount 
lenses on the Yashica's bayonet mount. What I would like to know is, are there
converters for Yashica -> Nikon? Canon? Anything other lens? I am planning to 
buy new lenses and would like to have a good range to choose from.      

__________________________________________________________________________
Chan Lee Meng          \  "You're the wrong man at the wrong place
739chan1@gw.wmich.edu    \   at the wrong time!"
X92chan3@gw.wmich.edu      \   "Story of my life."
Western Michigan University. \   - Die Hard II
From: ka1gt@cbnewsm.cb.att.com (robert.m.atkins)
Newsgroups: rec.photo
Subject: Star colors (was Re: moonlit landscapes / stars (4x5)
Date: 16 Oct 92 18:06:35 GMT
Distribution: na
Organization: AT&T

In article <1992Oct16.160954.12569@mercury.cair.du.edu>, troby@diana.cair.du.edu (Thorn Roby) writes:
> sky - the results were fairly normal color in the landscape, with white
> star trails of varying thickness. I haven't tried printing this yet myself
> to see whether I can coax some more color out of them. My guess is if you
> want good color in the stars you probably want fast film and a dark sky -

Stars are very bright and almost all star photographs have totally
overexposed star images. Thus they appear white. For an interesting
experiment photograph Orion (star trails), and every 10 or 15 minutes
defocus the lens a little more. As the lens is defocussed, the star
images get bigger (and thus dimmer). At some point, where you are not
overexposing the star images, "true" colors will appear. Where this 
happens depends on how bright the star is. It is very difficult (impossible)
to get color images of both bright and faint stars at the same time.

===============================================================
Bob Atkins  AT&T Bell Labs  email (direct)  att!clockwise!rma
===============================================================
Newsgroups: rec.photo
From: doug@jhawk.b30.ingr.com (Doug Bradley)
Subject: Re: Cropping slides
Reply-To: doug@jhawk.b30.ingr.com.
Organization: Intergraph Corp. Huntsville, AL
Date: Thu, 8 Oct 1992 16:48:49 GMT

In article <1992Oct7.195453.610@andersen.co.uk>, sdpage@andersen.co.uk (Stephen Page) writes:
|> Can anyone suggest a good way to crop slides for projection?
|> 
|> I've seen masks in shops, but these look rather limited. The local photo
|> shop suggests using masking tape, which sounds rather unpleasant!

Leitz used to have some metal foil tape for this very purpose. I've used it with
good effect. It was silver (aluminum) about 1 cm wide. It was made especially for
the purpose of masking transparencies (adhesive didn't melt under
normal projection).

As for using masking tape, you might want to think about finding another photo shop!

Hope this helps,

Doug "I Like Leica" Bradley
Newsgroups: rec.photo
From: zrepachol@cc.curtin.edu.au (Paul Repacholi)
Subject: Re: F4s /8008s etc (Nikon)
Organization: Curtin University of Technology
Date: Thu, 8 Oct 1992 20:07:50 GMT

In article <ld3qtgINN9bc@appserv.Eng.Sun.COM>, fiddler@concertina.Eng.Sun.COM (steve hix) writes:
> In article <1992Oct5.195230.7354@cerritos.edu> jacobs@cerritos.edu writes:
>>(Lakhinder Walia) writes:
>>> This is regarding the eye-piece shutter provided for F4, and a small
>>> plastic masking cup for 8008s.
>>> I dont understand why should they be there at all, because my premise is:
>>> the metering has to be some where in the camera body - but not in the prism
>>> housing : for how would otherwise the matrix balance and flash fill exposure
>>> work..? 
>  
...
> Unless you have a leaky mirror (the which is up and locked during the
> exposure period), then why have the eyepiece shutter?  (Which is to say,
> it don't buy you anything if that's the case.)
> 

Making the mirror light tight when its up isn't high on the designer's list of
things to do. I'll bet he/she wouldn't want to bet on it.

> A more likely reason to have an eyepiece shutter would be for those cameras
> whose metering cells read off a half-silvered portion of the focusing screen,
> and who might be misled by getting extra light coming in through the eyepiece
> if you use the camera with your eye away from the viewfinder, like when you
> shoot something from a tripod.  (This would only be a problem in autoexposure
> mode, since you usually have to look through the finder to adjust manual
> exposure.)
> 
Several cameras leave the finder cells 'in circuit' durring the exposure, and
relie on 0 or very low light level in the prism. Stray light will bias exposure.
The Pellix/F-1HSMD/RT/EOS-1HS are the limit example of the mirror problem...

~Paul
From: monson@hobo.ECE.ORST.EDU (Ty Monson)
Newsgroups: rec.photo
Subject: Re: Question about FE-2
Keywords: Nikon, FE-2
Date: 15 Oct 92 21:26:01 GMT
Organization: ECE Dept.,OSU,Corvallis

In article <1992Oct15.143947.28399@murdoch.acc.Virginia.EDU> vhs6r@kelvin.seas.Virginia.EDU (Victor Hsiao-yu Shao) writes:
>I recently purchased an FE-2 camera, but the owner I got it from couldn't
>find the manual.  Anyway, my question is... is the shutter speed as
>determined by the light meter variable?  For example, if the indicator 
>on the light meter is between 250 and 500, would the camera take a picture
>at either one of the 2 speeds or would it actually take the pic at 400 or

      In auto-exposure, the electronically timed shutter provides
      a continuum of speeds. If the needle indicates a speed between
      250 and 500, you will get a speed between those numbers.
      (not so in manual mode, though.)
     
>something?  And does the meter measure to a zone VI or zone V?  I was reading
>the Practical Zone System by Chris Johnson and he said that some built-in
>meters place the subject on zone VI instead of V, and I was wondering if the
>FE-2 is one of them.  Is it possible to request the manual from Nikon?  Would
>it be worth the trouble?  And if so, how?  Your input is much appreciated...
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

 I think the FAQ has Nikon's phone number. Call them and ask about a
 manual. Not much trouble, not much cost.
Newsgroups: rec.photo