HDTenEightyP/NetNews huggingface dataset:
From: jle@edsr.eds.com (Johnnie L. Eskue)
Newsgroups: rec.photo
Subject: Re: Canon EOS A2 or A2E?
Date: 26 Jan 93 19:36:33 GMT
Reply-To: jle@helena.UUCP (Johnnie L. Eskue)
Distribution: usa
Organization: EDS Research, Dallas, Tx 75230

In article <74311@cup.portal.com> HERMES1@cup.portal.com (Douglas Brian Opfer) writes:
>I'm considering purchasing one of the Canon A2's and am interested in any
>opinions regarding the eye controlled focus on the A2E.  Is this really a
>worthwhile feature or something that would rarely be used?  Also, is this
>the ONLY difference between these two cameras?  Any comments or opinions
>would be helpful, especially from those who have already made this choice.
>
>Thanks in advance,
>Doug Opfer
>(HERMES1@cup.portal.com)



.
	I am also considering the purchase of an A2E. I would be 
interested in any info about current prices for the camera. 
I have only seen one advertised on POPULAR PHOTOGRAPHY that 
lists the price, all the others say 'CALL'. This is to be a 
replacement for my 6 ... or is it 8 ... year-old AE1-P. 

	I would be interested in experiences anyone has with the 
mail order sources. I understand some outfits will pull the 
accessories that come packed with the camera and charge extra 
for them. Ok, if I know in advance, but how much could I expect 
this to add to the advertised price of the body?

	Any recommended places to do mail order business with? This 
would be both for the body and a couple of USM lenses (28 - 105 (?)
 and a 100-300).

	Lastly, anyone know of any A2E 'kits', such as the 10S kit 
that comes with one USM telephoto zoom and bar-code scanner?

---------------------------------------------------------------
Johnnie 'I can type 60 misteaks a minute (goin for 90!)' Eskue
uunet!edsr!bigdaddy!jle
Organization: Ha! Have you SEEN my desk???
---------------------------------------------------------------
Newsgroups: rec.photo
From: wtyler@adobe.com (William Tyler)
Subject: Re: Photographic Lens Flare Theory
Followup-To: rec.photo
Summary: Flare is complicated!
Organization: Adobe Systems Inc., Mountain View, CA
Date: Thu, 28 Jan 1993 00:22:34 GMT

In article <1k6vu4INNp5n@life.ai.mit.edu> bstevens@hal.gnu.ai.mit.edu (Bob Stevens) writes:
>I'm trying to find out more about how the effect of a lens flare 
>occurs.  In particular I'm curious as to what controls/causes the size 
>of the various disks and circles of light, their color and color 
>changes, the number of these and such.  I'm trying to create a computer 
>program to replicate this effect accurately and I'd like it based on a 
>real world model rather than my own "best guess".
> 
>Has anyone ever run across a paper or article on this?
> 


Flare is extremely complex. I'll just run down a list of some of the
things that can cause it.

1. Light that comes from outside the subject area but is imperfectly
absorbed by the lens hood and other baffling within the lens. 

2. Light that reflects from the air/glass surfaces (or glass/glass
surfaces) within the lens, perhaps multiple times. This may originate
either within the subject area or outside it. (Reducing this is the
purpose of lens coatings.)

3. Light reflecting off the film, back into the lens, and back again
to the film or to imperfectly black surfaces within the lens.

4. Light reflecting from imperfectly blackened portions of the camera
body interior.

5. Permutations and combinations of the above.

I've used the term 'reflect' to indicate both specular (mirror-like)
and diffuse (paper-like) reflections.

To accurately predict flare, you'd have to have an extremely good
model of the reflection/transmission/absorbtion characteristics of
every surface in the lens. This includes the baffling surfaces as well
as the lens elements themselves.

Incidentally, those pretty pictures that lens manufacturers use in
their ads, with lots of light disks showing off the surfaces in the
lens, are really admissions of failure. An ideal lens would be
completely invisible when looking into it from any angle in it's
designed field of view. (Actually it would look black, assuming the
camera were a perfectly absorbing black inside and the film didn't
reflect.) 


- Bill



-- 
Bill Tyler      wtyler@adobe.com
Newsgroups: rec.photo
From: acs@csri.toronto.edu (Alvin Chia-Hua Shih)
Subject: Re: Prices in Japan
Date: 24 Jan 93 16:34:17 GMT

In <1993Jan20.005959.1@cc.curtin.edu.au> zrepachol@cc.curtin.edu.au writes:

>In article <1993Jan18.222241.26024@sj.nec.com>, hisashi@lpd.sj.nec.com (Hisashi Naganuma) writes:
>...
>> Canon EOS-1 HS	Call				Call
>              ^^   For real? Do you have any more details??

It turns out that this is nothing more than an EOS 1 bundled with the
Power Drive Booster E1.  I guess we can all relax now!

>~Paul

ACS
-- 
 ___ ___ ___ ______________________________________________________________
|   |   | __|      Democracy is not a way of getting better solutions.     |
| - | --|__ |           It's just a way to spread the blame.               |
|_|_|___|___|______________________________________________________________|
Alvin_C._Shih____________________acs@csri.utoronto.ca______________________|
Newsgroups: rec.photo
From: phg+@CS.CMU.EDU (Paul Gleichauf)
Subject: New Nikon AFD lenses to anticipate.
Keywords: 
	Nikon is apparently breaking with tradition and talking about
Organization: Carnegie Mellon University
Date: Thu, 21 Jan 1993 17:03:57 GMT

some new products before they are made available to retailers or even
NPS members.  In particular there is confirmed word about three products
for 1993, but without further details.  All are the recent D-type 
refinement readable only by the N90.  There is no official word about a
new high end body capable of using the D lenses to their fullest. 

	400mm f2.8 telephoto
	105mm f2.0 "portrait" lens with defocus control
	20-50mm wide angle zoom (I may have the lower range wrong.)

Again no information about introduction dates, costs, weights, etc.
I will be following this fairly closely and will post further information
when it becomes available, unless someone else posts first.

						Paul

Newsgroups: rec.photo
From: afd@bellcore.com (Alex F. Dietz)
Subject: Re: Clark Photo Developing
Reply-To: afd@bellcore.com
Organization: Bellcore
Date: Tue, 26 Jan 93 21:30:41 GMT


In general, I've been pretty happy.  Turn-around time
is about 10 days, and they are inexpensive.

Clark has these little stickers w/ your address and Clark's
on 'em that go on the film can.  It's a great idea.  A while
back the mailer envelope apparently got mangled & a roll fell
out.  It eventually made its way to Clark anyway.  I got the
prints.

Be sure to pay the extra 25 cents for "rush" handling.
I forgot last time and it took 4 weeks.  Whoosh.
From: auyeung@toadflax.cs.ucdavis.edu (Tak [UlTech] AuYeung)
Newsgroups: rec.photo
Subject: for sale: Canon EF70-210f/4 for >>$150<<+shipping
Date: 26 Jan 93 16:34:35 GMT
Distribution: usa
Organization: Department of Computer Science, University of California, Davis

Since my 35-70 is broken and Canon won't fix it for free, I'd like to
sell my 2-month old (bought for a trip in Christmas) EF70-210f/4.  It
is not USM, but is a straight 4, nonetheless.  I'll include the
invoice from Beach Camera, which they claim is the warrantee (and is
verified at a local Canon service center).

The price is pretty firm as a new 35-70 is about $100 (from B&H), and
the Tamron 28-200 (which I plan to buy) is about $270.  If I cannot
sell the 70-210 for $150, I'd just buy a new 35-70.

Please direct all offers to this account.  Thanks!

--Tak
Newsgroups: rec.photo
From: accwai@math.uwaterloo.ca (Andy Wai)
Subject: Re: Which 210mm 5.6 copal ? 
Organization: Math Faculty Computing Facility, University of Waterloo
Distribution: na
Date: Tue, 26 Jan 1993 15:08:26 GMT

In article <1993Jan26.113727.9273@spectrum.xerox.com> mcfarland.henr801c@xerox.com writes:
>
>Prices from B&H (Feb 1993) Sutterbug
>
>			   price    AoV  IC
>
>Sinar       Sinaron-s      $797     72   310
>Schneider   APO-Symmar     $792     72   305
>Rodenstock  Sironar-N      $625     72   301
>Nikkor      Symmetrical    $510     72   301
>
>(AoV = angle of view; IC = image circle)
>
>All of these lenses are 210mm f5.6 copal, ranging in
>price from $500 to $800 (all unmounted prices). The cost
>difference is presumed to be a quality difference,

Probably not.  As far as I know, they're all Plasmat type lenses and they
all perform more or less the same.  The Schneider says Apo, but the rest
aren't really that far off.  The Nikkor, in particular, is known for it's
sharpness and contrast.  I have one in 180mm which I used quite a bit.  It
works quite well.

>although
>the two top priced lenses do have a larger image circle.

If angular coverage are the same, how can image circle be different?

>The question is, how much of a quality difference
>is there between the Rodenstock and Schneider that
>is worth $160. Similarily, is the Sinar
>better or worse than the Schneider ? 

As far as I know, Sinaron-s is actually relabeled Sironar-N.  The Sinaron
may be in DB mount though.  So check before you buy.  Anyway, they're all
good enough that they aren't the limiting factor in general.  So don't worry
about this kind of thing too much.  (Just my $.02 of course)

Andy Wai
Newsgroups: rec.photo
From: kassover@rumsey.crd.ge.com (David Kassover)
Subject: Re: cat(mirror) lens questions
Organization: nope
Date: Sun, 24 Jan 1993 02:48:24 GMT

In article <1jqi9jINN89v@usenet.INS.CWRU.Edu> bu890@cleveland.Freenet.Edu (Brian Segal) writes:
>
>You have to remember that when you get into 500mm and longer lenses
>the magnification of the atmospheric conditions is a significant
>factor in image quality...don;t shoot on hazy days if you want clear
>sharp pictures..also turbulence caused by local temperature
>fluctuations becommes a major factor.

Hard to find a not hazy day around here, lately.

How much atmosphere is acceptable?  5 miles? 1000 yards? 50 feet?
What's the close focus of the lenses in question?  One that I
have came with an extension, about 2.5 inches long;  it's
supposed to allow close focussing to 8 feet.  I'm not sure how
far out I can still focus with it installed...

Will filtration or polarization help?


-- 
David Kassover             "Proper technique helps protect you against
uupsi!khazad!kassover	          sharp weapons and dull judges."
kassover@aule-tek.com                   F. Collins
kassover@ra.crd.ge.com
From: huw@castle.ed.ac.uk (H G J Evans)
Newsgroups: rec.photo
Subject: Re: Big Switch: From 35mm to medium format
Date: 25 Jan 93 13:06:19 GMT
Organization: Edinburgh University

In article <1jm9hoINNq6j@cronkite.Central.Sun.COM> dbernard@clesun.Central.Sun.COM writes:
>Has anyone, after years of using 35mm SLRs, been able to
>succesfully shuck off their old investment, and turn entirely
>to medium format, and lived happily ever after?  The ease of
>use, ease of carry, low price of hardware and software (film,
>processing) make 35mm awfully attractive.  But has anyone turned
>their back on all that, and been happy with a shift to medium
>format, which shrugs off some of those attractive features of
>35mm in exchange for superior image quality?  I'd be interested
>in hearing your experiences.
>
>	Dave


  Well I certainly have. I bought into medium format in 1989, and my 35mm
gear hardly ever sees the light of day now. However, I think you have
got to bear in mind that the respective strengths of 35mm and medium
are not uniformly important, across the whole field of photography. If I
was interested in sports photography, for example, I would stick with
35mm because of the speed of use, availability of long lenses, etc.
However, these advantages are relatively insignificant to me, as I am
mainly interested in landscape, portraiture, and still life.
  Various people have mentioned missing things like zoom lenses,
sophisticated metering systems, and so on. I would have to say that I
miss things like that the way I would miss a hole in the head. My
photography seriously improved when I started with MF. I had only a
single, fixed focal length lens to work with, and had to learn to make
the best of it. Using a hand held meter again for the first time in
about fifteen years showed me just how my standards had slipped as I
had grown to rely on a TTL meter. All this, together with the need to
use a tripod forced me to slow down and to *work* at each shot. I was
beginning to *think* about my photography again, and indeed, beginning
to really enjoy it again. 


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%Huw Evans          huw@castle.ed.ac.uk     %
%                   huw@maths.ed.ac.uk      %
%                   Tel.  +44 (0)31-650-5067%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
From: mcfarlan@aurigaxerox.com (Doug McFarland)
Newsgroups: rec.photo
Subject: Re: Yet another purple tmax question
Date: 27 Jan 93 13:23:42 GMT
Reply-To: mcfarland.henr801c@xerox.com
Organization: Xerox Corporation


In article <1993Jan26.215823.12979@cs.sfu.ca>, bremner@cs.sfu.ca (David Bremner) writes:
|> 
|> I have just started developing TMAX-400 (actually I have just started
|> developing at all). 
|> 
|> I am using Kodak indicator stop, having cleverly noted that I should 
|> throw it out when it goes purple.  Unfortunately, it goes purple after
|> a single roll of TMAX.  Is this really exhausted, or is it just the
|> dye in the TMAX?
|> 
|> David
|> 
|> 
|> 
|> -- 
|> David Bremner / bremner@cs.sfu.ca / ubc-cs!fornax!bremner / (604)291-5938(days)


That seems a bit odd to me. I use D76 developer on TMY and do not have this problem,
even using an 8oz tank on 24 exposures. I should think a fresh quart of indicator stop
mixed to the recommended proportions should last for more than 10 rolls of Tmax.
Unless you are not draining enough developer back out of the tank (I assume daylight
tank processing) before you add the stop solution, you shouldn't have a problem. 

	doug


-- 
                       
               McFarland.henr801c@Xerox.com
Newsgroups: rec.photo
From: ajackson@ernie.Princeton.EDU (Andrew William Jackson)
Subject: Re: How Autofocus works?
Originator: news@nimaster
Organization: Princeton University
Date: Wed, 20 Jan 1993 01:30:11 GMT

In article <1993Jan19.172819.9064@sol.UVic.CA> mstoer@sol.UVic.CA (Marcell Stoer) writes:
>I would like to exactly how the autofocus works in the new SLRs.  I have
>noticed that the EOS cameras have two photodiodes below the mirror and
>I would like to know how they are used to focus the camera.  I want
>more than a handwaving explanation though.  I thought you could offset
>the two photodiodes and measure the ratio of their detected light intensities
>and compare this to some calibration table, but that would be very awkward.
>It probably wouldn't give much of a dynamic focussing range since you need
>to offset the diodes about 2-5cm for things to work well.  Clearly that's
>not possible in a 4-5cm camera body.
>
>Does anyone know exactly how this works?  If there are some publications
>on this I wouldn't mind the references.
>thanks,
>-ms
>-- 
>Marcell Stoer                                Internet : mstoer@sol.uvic.ca


I always thought the camera tried to maximize high spatial frequencies
in the 2d fourier transform of the image.  For vertical patterns this 
should only require 2 diodes.
From: zrepachol@cc.curtin.edu.au
Newsgroups: rec.photo
Subject: Re: B&W Film question
Date: 24 Jan 93 15:18:56 GMT
Organization: Curtin University of Technology

In article <1993Jan23.040021.7843@walter.bellcore.com>, ekim@nyquist.bellcore.com (Michael Mills 21340) writes:
> 
> I need to buy some film for a photo class I will be taking.  Can someone
> tell me the difference between the following films:
> tri-X ( 400 )
First released in 1955, though its been reformulated several times. Good
highlites, ok grain.

> Plus-X ( 125 )

Older than TX, beloved of portrait shooters. Good grain.

> T-Max (400 & 100 )
TMX 100, Better grain than old FX ( 32ISO ). Nice in D-76 or Rodinal, but a bit
'mushy' in TMAX developer.

TMY 100, grain about PX, *VERY* different animal to TX. Can go to a highlite
density of 3.5+ if over developed, hence near un-printable.

The TMAX films are very fussy in processing compared to the older emulsions.

The coment on TX BTW do NOT apply to tri-X pro!!


> 
> Also on the list of equipment it says to get. Kodak Polyfiber 8 x 10
> double weight glossy paper.
> 
> I have seen Polyfiber (A)FB-F Glossy Double weight
> and (B)Polyfiber FB-F Double weight.  I assume that B is
> not glossy and that I should get A. Does this make sense.
> 

In the big yellow paper world, F -> glossy. Seems like different labeling of
same paper.

Why do they want to inflict you with FB, rather than RC paper?

~Paul
Newsgroups: rec.photo
From: zrepachol@cc.curtin.edu.au
Subject: Re: Advice Needed on Photographing Fire
Organization: Curtin University of Technology
Date: Sat, 23 Jan 1993 19:25:33 GMT

In article <1993Jan22.110804.2875@spider.co.uk>, mikec@spider.co.uk (Mike Coren) writes:
> 
> Can anybody offer any pearls of wisdom in regards to photographing fire?

Sorry, forgot one other detail. Contact the organizers and try to find out
how the intend to set the fire. You can then do a 'test' in you back yard
to get exposure etc trialed and see what you like. And try to make sure you
are not down-wind!!

~Paul

Newsgroups: rec.photo
From: ka1gt@cbnewsm.cb.att.com (robert.m.atkins)
Subject: Canon 300/4L and Tamron 1.4x test data
Organization: AT&T
Date: Fri, 22 Jan 1993 19:07:17 GMT

I thought there might be interest on some recent test data on the Canon 
EF300/4L and the TAmron 1.4x converter. Using Fujichrome 100 slide film,
bogen 3051 tripod with 3047 head, Canon EOS 10s body, mirror lock up.

At the center of the frame at f4 and f5.6 (no discernable difference)
I could resolve 88 lp/mm. I have a hard time believing this myself, but
it is there. I would not have thought you could see 88 lp/mm on
Fujichrome 100. However I can JUST detect modulation in the 1/5 group
of the USAF target (3.17 lp/mm) and in a 3.2 lp/mm group on a second
target, so I'm pretty confidant. Target magnification was about 1:28
(almost full frame of the 24"x36" Edmund Scientific chart). Even if
I'm being over optimistic, the next pattern down (2.8 lp/mm) was
clearly resolved, which would indicate resolution better than 78 lp/mm.
Ther was no sign of lateral color even at the very edge of the frame.
I didn't measure edge resolution yet.

With the Tamron 1.4x, center resolution dropped to ca. 72 lp/mm. Still
a very good number. However at the edge of the frame there was clearly
some lateral color and lower resolution (numbers not measured yet).
These results were from both f4 and f5.6 tests which were hard to tell
apart (at least at first glance). I assume that the Canon 1.4x would
do even better (especially at the edges), though there is quite a
price difference ($90 vs. $300) between the Tamron and Canon units.

If I do more measurements I'll let you know.

Technical note: If you believe Fuji data (RD100, 125 lp/mm for high
contrast target) and assume a diffraction limited lens (resolution
= 1600/f#) then you would conclude that you should be able to see
95 lp/mm at f4 and 87 lp/mm at f5.6 from a perfect system.
In the real world it is hard to beleive you could even come close
to this, so even I doubt my 88 lp/mm figure and 80 lp/mm still sounds
too high. I will re-evaluate my results and post any problems I find

===============================================================
Bob Atkins  AT&T Bell Labs  email (direct)  att!clockwise!rma
===============================================================
From: mcfarlan@aurigaxerox.com (Doug)
Newsgroups: rec.photo
Subject: B&W paper developer
Date: 23 Jan 93 11:24:19 GMT
Reply-To: mcfarland.henr801c@xerox.com
Organization: Xerox Corporation


Has (is) anyone using Fred's formula (Zone VI) paper developer or
Zonal paper developer ? Also, in the zone VI catalog they sell
Benzotriazole, a restrainer, could someone comment on the
effectiveness of this product ? (I hope this isn't going to be
an emotional issue :)

		thanks - doug

-- 
                       
     ||            ||        McFarland.henr801c@Xerox.com
     ||\/\/\/\/\/\/||
     ||            ||/|
     ||            || |
     ||            ||\|
     ||/\/\/\/\/\/\||
     ||            ||
 o==[  ]==========[  ]==o
     ||  |-----|   ||
     ||   \---/    ||
Organization: Penn State University
Date: Mon, 25 Jan 1993 00:34:02 EST
From: <RHG@psuvm.psu.edu>
Newsgroups: rec.photo
Subject: Lightning Photo Hints

Thanks to all of you who provided me with hints for lightning
photography.  The article on lightning-photographer Warren Faidley
is in the February issue of Popular Science, with the do-it-yourself
material appearing in a box.
======================================================================
Robert Gannon              |  Bitnet:    RHG@PSUVM
35 Burrowes Bldg.          |  Internet:  RHG@PSUVM.PSU.EDU
Penn State                 |  Phone:     814 355-4800 or 355-0943
University Park, PA 16802  |  Fax:       814 863-7285
Newsgroups: rec.photo
From: keithh@bnr.ca (Keith Hanlan)
Subject: Re: Is there a new Minolta Camera?
Organization: Bell-Northern Research Ltd., Ottawa
Date: Wed, 27 Jan 1993 15:01:21 GMT

In article <1993Jan26.115215.22931@spider.co.uk> mikec@spider.co.uk (Mike Coren) writes:
>I don't know about a new high end, but I've heard that in Japan you can buy
>Minolta Dynaxes with a special "panoramic" option that lets you take panoramic
>pictures.

The panaramic adaptor can be put into any Maxxum/Dynax i or ix series
camera. It is a $30 attachment. It is a replacement mirror plus the
tool for safely replacing it. The xi series cameras recognize the
attachment and display the panoramic dimensions in the viewfinder.

Keith Hanlan  KeithH@bnr.ca  Bell-Northern Research, Ottawa, Canada 613-765-4645
Newsgroups: rec.photo
From: yz3k@galen.med.virginia.edu
Subject: Re: EF 75-300 (was Re: Elan Telephoto Zoom Lenses)
Organization: University of Virginia
Distribution: na
Date: Sat, 23 Jan 1993 18:16:20 GMT

In article <1993Jan21.180920.29010@cbnewsm.cb.att.com> ka1gt@cbnewsm.cb.att.com  
(robert.m.atkins) writes:
stuff deleted
> 
> First SQFs at 8x enlargement (8x10)
> 
Try the data at greater than 8x enlargement. You'll see the Canon lens  
performing worse and worse. 
yz
Newsgroups: rec.photo
From: dp@world.std.com (Jeff DelPapa)
Subject: Re: How dangerous are developer chemicals?
Organization: The World Public Access UNIX, Brookline, MA
Date: Wed, 27 Jan 1993 07:31:25 GMT

In article <1993Jan26.220603.7452@midway.uchicago.edu> ar12@midway.uchicago.edu writes:
>High there- just a brief, non technical point of interest...
>	Many photographers, including the late Ansel Adams, don't use
>tongs or gloves in developing prints- not doing so enables one to
>determine required stop bath time- ie: when the print loses that slimy,
>alkaline feel and becomes "squeeky" its done- easy way to
>compensate for stop bath neutralization with use- I know, no big deal...

It depends greatly on which bath you are sticking fingers into - Stop
is half strength vinegar, and if you are using one of the more benign
developers, I might pass on that, but if you are using one of the pyro
formula's use tongs, gloves and a ventilator... Even one of the
"benign" ones like metol, has been known to result in real contact
dermatitis problems to people that have had long term exposure...
(some of the population can't cope with it from the start, others are
fine for a number of years, then over a short period of time they
develop a serious alergic problem, and can't stand to be in the same
county as the stuff... human bodies are strange - some things have
real threshold problems - you have no problems for years and years,
then you cross the dividing line, and latch hard in the other
state...)

<dp>