HDTenEightyP/NetNews huggingface dataset:
From: rspeirs@javelin.sim.es.com (Ron Speirs)
Subject: Re: Lamp intensity vs. lifetime 
Organization: Evans & Sutherland Corp.
Date: Fri, 20 Nov 1992 18:49:10 GMT

In article <MAS.92Nov18103752@mipl8.jpl.nasa.gov> mas@mipl8.jpl.nasa.gov (Marc Sarrel) writes:
>
>I think that if you _really_ want to go overboard, run your lights off
>DC (the real stuff, not half-wave rectified) and vary the voltage.  I
>seem to remember that the lights in Thomas Edison's house in Michigan
>(originally in New Jersey, but after TE died, Henry Ford moved it) are
>still burning, at least in part, because they're run off DC.
>
From what I have read, I don't think DC would result in greater lamp life.
To quote from Sylvania Miniature Lighting Products Handbook, page 11:

"Evaporation and Notching.  During its normal operating life as an incandescent
 element, the tungsten filament steadily boils off tungsten atoms at a rate
 strongly dependent upon the temperature.  Ideally, the evaporation would
 uniformly reduce the filament cross sectional area, increasing its resistance,
 and reducing the power per unit area of surface; the filament would simply
 fade away as it aged, and all filaments would have the same life expectancy.
 Unfortunately, uniform evaporation does not occur in practical cases.  Non-
 uniformity of filament material, of cross-sectional area, traces of lower-
 melting-point materials, mechanical effects of cold working, and similar
 influences produce anomalies that cause preferential evaporation.  Notches
 are formed at tiny hot spots in the filament, until eventually a very slight
 shock causes the filament to snap at the weakest notch.  Since the size of
 the notches seems to be independent of the size of the filament, thinner
 filaments show a reduced life compared to larger, higher current rated
 filaments.  For equal power, AC appears to cause much less notching than
 DC, and gives a life from two to ten times that obtainable with DC.
 Notching is most significant in the 1700 K to 2300 K filament temperature
 range.  In general, it is advantageous to employ higher-current, lower-
 voltage filaments, and to operate from AC, for greatest life and reliability."

Let's not forget that Edison favored DC power transmission, and the genius
behind AC transmission (and the ability to transform voltage up or down)
was Nikola Tesla.  If Edison had had his way, we would have needed a small
generating station in every neighborhood.

Ron Speirs, Evans & Sutherland Computer Corp., Salt Lake City, Utah

Newsgroups: rec.photo
From: steveh@pilot.dmg.ml.com (Steve Hannoford)
Subject: Re: candids
Organization: Merrill Lynch Debt Markets Group
Date: Wed, 18 Nov 1992 21:04:58 GMT

I have taken lots of candids with reasonable success.  
I really don't like posed shots, and if I am shooting
friends at a back yard BBQ it can be difficult.

Start by walking around with the camera everywhere.
 At some point, make a point of fussing with the camera,
 as if you had trouble with the lens.  Try focusing on
 something pointed away from everyone.  Grumble about 
 the camera, and act as though you've given up on taking
 shots.  I find that many people will stop paying attention,
 and can easily be shot candidly at this point.

Also try focusing on a subject that is equidistant from you
 as your real subject.  At the last second, turn to your
 true subject and shoot.

Also try posing 1 or more people for a fake shot, while 
 shooting someone 'in the background' - a zoom lens is
 good for this.

Oh, yes - one of my favorites -->  take a wide-to-tele
 zoom ( 35-200 is what i have ) and put it on wide and
 let people look through it - show them that the lens
 is a wide angle lens and covers the whole yard.
 Take all of your shots on telephoto.  Even if people
  see you shooting a picture - they don't realize that
  you are zoomed in on them.

-- 

+-------------------------+--------------------------------------+
| steveh@pilot.dmg.ml.com | My employer has no opinions and has  |
| Steveh Hannaford        |  nothing to do with anything I say.  |
Newsgroups: rec.photo
From: feldman@hal9k.cxo.dec.com (james feldman)
Subject: Re: Reliable Strobe System (Speedotron,DynaLite, etc) ?
Reply-To: feldman@hal9k.cxo.dec.com (james feldman)
Organization: Digital Equipment Corporation
Date: Mon, 16 Nov 1992 18:02:48 GMT

In article <1992Nov13.143546.8691@cis.ohio-state.edu>, ray@anaconda.cis.ohio-state.edu (william c ray) writes:

|>Speaking of reliable strobe systems, I'm looking for a 
|>suggestion or two on something that would be bomb-proof,
|>high output, battery powered, (and cheap?)...
|>
How about the norman or lumedyne systems.  They're not cheap, but they WILL
pump some light according to their specs.  Of course, you'll be toting a pack
about 1/2 the size of a small car battery...

--
Jim Feldman                         || This space for lease, contact your
Digital Equipment Corp              || Digital Sales Rep.
CSC/Colorado Springs                || 

My opinions are my own and in no way reflect Digital's POV (unless they're
charging somebody for me to give them).
Newsgroups: rec.photo
From: jchen@wind.bellcore.com (Jason Chen)
Subject: 80-200/f2.8 for $$$, why?
Reply-To: jchen@wind.UUCP (Jason Chen)
Organization: Bellcore, Morristown, NJ
Date: Thu, 19 Nov 92 03:59:57 GMT

There seems to be a lot of interest in fast but expensive zoom lenses such
as the 80-200/f2.8. I am sure there must be special applications where
the additional stop worth the money, but I can't understand why there is
so much interest in paying the large premium for the extra stop.

For example, the Canon EF 80-200/f2.8 L costs $925 (B&H as a reference), 
while the 50-200/f3.5-4.5 L costs $499. These two lenses equal optically.
The differences are the maximum aperture and the minimum focal length.
I would take the 50-200L any day to save that $425 and to gain
the 50-80 range at the sacrifice of one stop.

But then, I am no pro. There must be reasons for the popularity of the
80-200/f2.8 lens. What are they?

Jason Chen
From: yavor@acpub.duke.edu (Yavor B. Parashkevov)
Newsgroups: rec.photo
Subject: Re: Rebel vs. Rebel II (2)
Date: 19 Nov 92 20:42:46 GMT
Organization: Duke University; Durham, N.C.

In article <sue-d-191192111754@mac179.mech.nwu.edu> sue-d@nwu.edu (SUE DAKIMOWICZ) writes:
>I am going to purchase a Canon Rebel ( I am also an amatuer photographer) 
>When I was calling around for the best price,  the salesperson told me
>about the new Rebel II and gave me a price for a kit (body, lens, and
>flash).  I asked what the difference was between the 2 and the original
>model and they could not give me any real info on it,  what they said was
>"well its a better camera".  
>
>So what I want to know is what advantage do I have if I get the Rebel II
>over the Rebel?
>
>Thanks in advance!
>
>Sue  
>
>sue-d@nwu.edu
>Northwestern University
>Mechanical Engineering Department
>Evanston, IL  60208

I can't remember off the top of my head what the differences are, but
I think it has 1/2000 shutter speed (Rebel has 1/1000) but I may be
wrong on this. What I am sure about, however, is that Rebel II has a
*built-in flash*. So, if someone is trying to sell you over the phone
a kit that includes a flash, they may very well be trying to reap you
off by treating the built-in flash as the flash included in the kit.
Beware of nasty dealers! I think Popular Photography recently had
something on exactly this sort of sales practice.
Hope this helps.

Yavor Parashkevov

e-mail: yavor@acpub.duke.edu
snail:  2422 W Club Blvd
        Durham, NC 27705-0325
        USA
Newsgroups: rec.photo
From: bbarton@Ingres.COM (Brian Barton)
Subject: Jay Maisel: Light, Color & Gesture
News-Software: VAX/VMS VNEWS 1.4-b1  
Keywords: no posers allowed
Organization: ASK Computer Systems, Ingres Product Division
Distribution: na
Date: 17 Nov 92 17:28:58 GMT


Just thought I'd post a little blurb after seeing Jay Maisel's lecture at 
U.C. Berkeley's Dwinelle Hall on Monday November 16, 1992 on "Light, Color &
Gesture" on behalf of U.C. Berkeley's Journalism School.

Review:

Very nice presentation.  He spoke for about 45 minutes and then proceeded to 
show about 100 slides of some of his work.

Although I don't find his work to be particularly inspiring, he was very nice
and pleasant and seemed genuninely interested in his and other people's work. 
He answered questions from the audience after he was done, and overall, I 
really liked it.

A friend of mine told me that he was pretty "arrogant" and stuff, but I didn't
find him particularly so.  He did do his quota of "name dropping:"  

"When I was shooting for 'A Day In The Life of Tokyo'..."
"When I was shooting for the 'Sports Illustrated Swimsuit Issue'..."

but hey...the guy's a heavyweight so he should be able to brag. :)

My totally incomplete information tells me that he is off to Southern California
for his next lecture.  I don't know when or where so don't e-mail me. :(  The 
lecture was sponsored by Kodak's Professional Photography Division and is part
of a lecture series on behalf of a now-dead photographer (whose name now 
escapes me.)

If he comes to your town, check it out!  It's free, too.  Cool free posters of
one of Jay's images from Jerusalem were also available for the taking.  (and
for his John Hancock if you so desired...)

Cheers!


Brian
bbarton@ingres.com
From: eugene@briar.lle.rochester.edu (Eugene Kowaluk)
Newsgroups: rec.photo
Subject: Reliable Strobe System - Speedotron
Date: 16 Nov 92 21:47:56 GMT
Organization: UofR Laboratory for Laser Energetics


 
 
Scott Thull writes:
 
> >Speedotron Black Line: Reliable, flexible, short recycle times, powerful.
 
Thanks for a nice summary Scott.
 
I've used a Black Line 4803 for several years with no problem.  I usually
run three heads off of it.  However, it is a very difficult unit to control
the heads separately.
 
 
>      +- reliability (if you have three heads and the power pack breaks 
>                      you have none! but.. since lamp heads are lighter
>                      and seperate from most of the electronics, they usually 
>                      survive shocks that a monolight might not.)
 
I've had a light fall 15 feet, breaking the light box, denting the
housing, but not damaging the lamp.  However, the lamp heads on
the Black Line are not that light, especially with custom reflectors.
 
 
>       + most lamp heads can have fans for continous use
 
Making it difficult to cool when the light box is fully enclosed.
 
 
eugene kowaluk
 
Newsgroups: rec.photo
From: lsr@taligent.com (Larry Rosenstein)
Subject: Re: photomanipulation
Followup-To: rec.photo
Organization: Taligent, Inc.
Date: Thu, 19 Nov 1992 02:09:56 GMT

In article <BxJ492.1tw@sti.com>, coyote@sti.com (Ron Lussier) wrote:
> 
> One good example is the cover of 'A Day in the Life of California'.  As I
> understand it, the background was 'cleaned up' inthe cover picture of the
> surf-boy.

In fact, I seem to recall that the surfboard was damaged in the original,
and they "repaired" for the cover.  Also, for the cover of "A Day in the
Life of America" I think they took a horizontal photo and rearranged the
elements to better fit the vertical cover.

In addition to the Pop Photo article on this, one of the desktop publishing
magazines (probably Publish) had an article about photo manipulation.

Larry Rosenstein
Taligent, Inc.

lsr@taligent.com
From: auyeung@toadflax.cs.ucdavis.edu (Tak [UlTech] AuYeung)
Newsgroups: rec.photo
Subject: EOS Lenses: EF75-300,EF75-300USM or Tamron 28-200?
Date: 17 Nov 92 01:50:33 GMT
Distribution: usa
Organization: Department of Computer Science, University of California, Davis

Hi!  I'm a beginner with an EOS 630 and the EF35-70 f/4 lens.  I'm
planning to buy a tele-photo zoom, and the following are my options:

Canon EF 75-300 (non USM)
Canon EF 75-300 (USM)
Tamron AF 28-200

I know the USM is quieter (for human hearing range) and faster, but the
extra $50 seems hefty if picture quality is the same as the non-USM
version.  Besides, the 630 is not exactly a quiet body anyway.  Has
anyone compared the picture qualities of the two lenses?  I guess they
are of about the same physical sizes as well, so please correct me if I
am wrong.

The Tamron offers a wide useful range on the same 15oz. lens.  But I
am worrying about the picture quality and speed.  The $265 price tag
seems a bit heavy, but I can always sell the then-useless EF35-70.  If
you have any experience (good or bad) about the Tamron, please let me
know!

I'm also interested in the EZ430.  I know the off-camera cord does not
work with the 630 and a guy in G.B. has a fix for it.  Has anyone used
the fixed cord?

If you have any information to share, please kindly reply to this
account as I am sure such topics have been discussed a lot on the net.
Thanks!

--Tak
Xref: sparky rec.photo:20278 misc.forsale:31682 or.forsale:2025
From: al@qiclab.scn.rain.com (Alan Peterman)
Newsgroups: rec.photo,misc.forsale,or.forsale
Subject: Camera Gear For Sale
Date: 21 Nov 92 17:25:30 GMT
Article-I.D.: qiclab.1992Nov21.172530.21725
Distribution: usa
Organization: SCN Research/Qic Laboratories of Tigard, Oregon.


                  35mm Camera Gear For Sale
 
I've got to get rid of the excess gear in my camera drawer!
 
Olympus OM-1 MD chrome.  The original manual body, with motor drive port
and including flash shoe.  Has mirror lock, self timer, and in very nice
condition.  $120.  (with below lens $150 for the set!)
 
Olympus Zuiko 28mm F 3.5 lens.  Good wide angle.  $45.
 
Olympus XA with A-11 flash.  A semi-classic compact rangefinder with
sharp 35/2.8 lens.  Aperature preferred autoexposure with shutter
speed readout.  Very nice condition, in presentation case.  $125.
 
Pentax auto 110.  Maybe the smallest SLR ever made.  Includes 24mm F2.8
lens. Too bad I was dumb and sold the zoom!!  $65.
 
Pentax ME Super Black Body with 50/1.4 Pentax A lens and case.  NICE
camera with shutter speeds from 4sec to 1/2000th.  Aperture preferred
auto mode, manual mode, exposure compensator, self timer and UV filter.
$165 for the whole thing!
 
Canon FTb(n) with FD 50/1.8 SC lens.  Manual body with mirror lock,
depth-of-field, self timer and shutter readout in viewfinder.  Includes
case, 55mm UV filter and rubber lens hood.  $135.
 
Vivitar 283 flash.  Tilt with removable sensor.  Includes filter set
for varying color and wide angle flash, and remote cord for sensor.
$45 for the whole setup.
 
I am looking for a decent flash meter - and am open to other offers,
but I do think my prices are fair.  Prices do not include shipping,
but I do give a satisfaction guarentee and will take back anything
not up to YOUR standards for a refund, but this gear is all pretty
good to excellant.

 
-- 
Alan L. Peterman                                 (503)-684-1984 hm & work
                       al@qiclab.scn.rain.com
It's odd how as I get older, the days are longer, but the years are shorter!
Newsgroups: rec.photo
From: robert@sys.sweden.dg.com (Robert Claeson)
Subject: Re: The color developer in the E-6 process
Date: Tue, 17 Nov 1992 12:46:34 GMT
Organization: Data General AB, Akalla, Sweden

In article <1992Nov9.192006.8736@odin.corp.sgi.com>, donl@glass.esd.sgi.com (donl mathis) writes:

> In article <1992Nov9.083257.12221@sys.sweden.dg.com>,
> robert@sys.sweden.dg.com (Robert Claeson) writes:

[deleted]
> |> Note that I'm currently using a 3 step kit intended for professional use,
> |> not a 6 step kit.
> 
> Three steps?  That must mean that the reversal bath is stuck in with
> the color developer in step 2.

Yes. They're combined into one 6 minute step.

[deleted]
> The next step, which is likely bleach/fix, will bleach the developed
> silver back into silver salts, and once that's done, the bleach will
> just slosh around in there.  The fixer will collect all of those silver
> salts, and once that's done, it will just slosh around in there.

That's also correct, the bleach and the fix are combined into one 6 minute
step.

> Wash thoroughly, but once the film is washed, the water will just slosh
> around in there without doing much.

I use to wash the film for a substantially longer time than the 6 minutes
the instructions says -- around 20 or 30 minutes, after which I end the
processing with the stabiliser before hanging the films up to dry. Six
minutes sounds just too short for me who is accustomed to rinse my b&w
films at least 30 minutes and often as much as 60 minutes.

Anyway, than's for the info. Now I know.

-- 
------------------------------ END OF MESSAGE ------------------------------
Robert Claeson                Internet: robert@sys.sweden.dg.com
Data General AB                         robert@sys.dg.se
Box 28                             CEO: robert@sys.sweden.dg.com:dg-smtp
S-164 93 KISTA                     Tel: +46 (0)8-92 55 00
Sweden                             Fax: +46 (0)8-751 36 22
Newsgroups: rec.photo
From: sch@unx.sas.com (Steve Holzworth)
Subject: Re: Disclaimer on Photos
Date: Thu, 19 Nov 1992 17:32:22 GMT
Distribution: usa
Organization: SAS Institute Inc.

haddaway@umbc5.umbc.edu (Mr. Todd Haddaway; ADMIN-COMP) writes:

>I am starting to send concert photos to record companies and magazines.
>What sort of disclaimer message should I stamp on the back to say
>"You can't use this photo unless I give you some sort of permission".
>I want the people to see the photos but not be able to use them unless
>we work out some sort of payment.

>Thanks,

>Todd

Well, first, don't just send photos willy-nilly to magazines and studios.
It won't do you any good. Write and ask them for their submission guidelines
(an address is usually in the front of the magazine, near the circulation
info). The submission guidelines usually quote what their standard usage
terms are (rights, fees, etc.). They also usually disclaim any liability for
lost or damaged photos/slides, if they are unsolicited. This is a pretty
low-percentage method of getting published (or even noticed), but might
be worth the effort.

For the second part of your question: generally

Copyright 1992 Joe Blow - All Rights Reserved
Foo Studios (if you are one)
123 Main St.
Anywhere, Anystate, 12345


should suffice. By international law, you have an implied copyright the 
moment you create the work. The above merely helps assert your case. Before
you could prosecute an infringement, you would also have to register the
copyrighted work with the guv'mint. This isn't necessary (and is expensive)
until you actually have to go after someone.

In any case, you want your address on there in case they decide they DO want
to get in touch with you.


--
Steve Holzworth
sch@unx.sas.com
x6872
SAS Institute - Open Systems R & D
Cary, N.C.
Organization: Hunt Institute for Botanical Documentatn, Carnegie Mellon, Pittsburgh, PA
Newsgroups: rec.photo
Date: Mon, 23 Nov 1992 10:35:37 -0500 
From: "Frank A. Reynolds" <fr0c+@andrew.cmu.edu>
Subject: "Lightmaster" Enlarger Meters 


I have come across a 1975 "PhotoGraphic" review of "Lightmaster"
enlarger meters.  Has anyone used any of the "Lightmaster" meters
before?  Do you where I can get some information on them or who sells
them if they are still being manufactured?
From: TSOS@uni-duesseldorf.de (Detlef Lannert)
Newsgroups: rec.photo
Subject: Re: Question for photo techies
Date: Tue, 17 Nov 1992 11:15:13 GMT
Organization: Universitaetsrechenzentrum, Heinrich-Heine-Universitaet, Duesseldorf
NNTP-Posting-Host: lannert.rz.uni-duesseldorf.de

In article <1992Nov13.233001.17136@digi.lonestar.org> gpalo@digi.lonestar.org (Gerry Palo) writes:

>Here is a question/proposal for photo techies, perhaps Kodak 
>types or others interested in camera, film, and enlarger/printer 
>manufacturing technology.
>
>Would automatic printers be better able to adjust for correct 
>color balance if, in addition to scanning the  negative and 
>taking manual input from the human operator, they knew the 
>actual settings and conditions under which the picture was taken?
>
>Suppose we could have a 35mm or other film with a magnetic strip 
>on which an auto-exposure camera could record the exposure 
>information  [...]

Sorry to disappoint you - but that has been invented before ;-) ...

Actually there had been rumours that Kodak or someone else would
come up with a 24x36 film that carries such a mag strip to record
certain relevant data. It was expected to be presented at photokina
in September, but it wasn't. Either the rumours were wrong or they
cancelled the thing.

The mag strip should also record a size information so that a cheap
"zoom" feature could be built into the cheapest p&s cameras: The user
"zooms" by moving a mask in the viewfinder, the position is recorded
on the film, and an appropriately selective enlargement is made by
the automatic printer. Arrrrrggggh! (Quality would be "no problem";
the films are sharp enough anyway, compared with the average picture
quality people wouldn't notice they are being cheated ...)

It was also speculated that Kodak would supply a film for 24x36 (with
mag strip) with no perforation on either side so that compact p&s's
could be made a bit smaller yet.

(All these rumours come from some [German] photo magazine; they circulated 
them perhaps 4 or 5 months ago.)

Let's hope Kodak are so busy with (developping, producing and defending)
Photo CD that they forget about this crap ...
--
Detlef Lannert      DC3EK      E-Mail: tsos@rz.uni-duesseldorf.de
"Gedanken sind nicht stets parat,
man schreibt auch, wenn man keine hat."             Wilhelm Busch
From: jack@dcs.glasgow.ac.uk (Jack Campin)
Newsgroups: rec.photo
Subject: Re: Darkroom Ventilation
Date: 23 Nov 92 14:47:46 GMT
Reply-To: jack@dcs.glasgow.ac.uk (Jack Campin)
Organization: COMANDOS Project, Glesga Yoonie

bjs@RUTS.ccc.amdahl.com (Barry Sherman) writes:
> But I'm not aware that the odors of acetic acid, fixers and standard paper
> developers are dangerous.  Anyone know for a fact?

In some people, the sulphur dioxide given off by most developers can induce
a severe generalized allergy syndrome after prolonged exposure; this happens
to X-ray technicians and people working in one-hour labs (the latter often
have bad ventilation).  This leaves you getting acute asthma attacks not
only on re-exposure to SO2, but also many other common volatile chemicals.
I don't know of any cases resulting from ordinary amateur darkroom usage.

The vapour given off by selenium toner is extremely toxic.  You probably
knew that.  Incidentally, does anyone know the exact point of the "for
professional use only" on the label of the Kodak one?  I assume it's a
piece of corporate ass-covering, but quite how it would work legally I
can't imagine - no shop has ever asked me if I was a professional when
buying it.

-- 
--  Jack Campin    room G092, Computing Science Department, Glasgow University,
17 Lilybank Gardens, Glasgow G12 8RZ, Scotland   TEL: 041 339 8855 x6854 (work)
INTERNET: jack@dcs.glasgow.ac.uk or via nsfnet-relay.ac.uk    FAX: 041 330 4913
BANG!net: via mcsun and uknet     BITNET: via UKACRL    UUCP: jack@glasgow.uucp
Newsgroups: rec.photo