Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
This archived listing popped up in the For Sale section today: http://web.archive.org/web/201611061...-240-270-305mm The seller claims that the lenses he offers have enormous coverage.
His listing referred to this old discussion http://www.largeformatphotography.in...overage/page10 (this link goes to p. 10 of the discussion, not to its start). It is safely put away on archive.org. See the Burleigh Brooks propaganda that the seller kindly put up in post #97 of the discussion.
The propaganda disagrees strongly with the coverage claims in the for sale listing. It also says that two of the three lenses the seller offers are plasmat types. The third lens on offer is an f/6.8er and there seems to be no solid information on the type. I calculated that the seller claims the lenses cover ~95 degrees. I could be mistaken, but I don't believe there are any 95 degrees plasmat types.
Also read the discussion from the beginning. Its very interesting. Starts out with extravagant coverage claims and great enthusiasm, peters out in confusion and disappointment over coverage claims not met.
Re: Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
Re: Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
i photographed a 8x10 ground glass using my cellphone and while you can't see it well in the photograph
the 150f6.3 illuminates ( i would hate to say "covers" ) it without a problem.
i use this lens on 5x7 without any coverage problems and ive wanted to put it on a larger camera and measure
the image circle because while i have heard it has a large image circle, ( and expereinced no issues )
ive also been told it doesn't have a large image circle at all. the lens was on a 8x10 sinar board when i i bought it
and the person who sold it to me said the guy who had it before me used to use it all the time on his 8x10
( product close ups? macro work? who knows ) i've talked to people who know more then me often about this lens
because i've heard conflicting info, and was told by jim at mepex that there were supposedly some of these lenses
that had "large coverage" but he had never come across any, ..
while the attached photo is of the ground glass and is kind of dark ( sorry its from a big box i use to expose retina prints )
originally i used a huge sheet of waxed paper and even though i got a massive image on it, ( the box is 11x14+ ) there was
a huge glare spot so i went ahead and put a 8x10 glass+ its frame on box and a book inside the "camera".
i could easily move the ground glass frame around without loss of image .. but unfortunately the image is dark
so you really can't see what i saw ...
all i can say is its bigger than 5x7, how much bigger i don't want to say.
Re: Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
My questions regarding the thread were, whether or not the negatives would stand up to enlargement and queried some of the participants about this. I think that the claims related to contact printing only.
Re: Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
This message has been deleted by BrianShaw
Re: Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
Quote:
Originally Posted by
neil poulsen
My questions regarding the thread were, whether or not the negatives would stand up to enlargement and queried some of the participants about this. I think that the claims related to contact printing only.
Neil, what was posted was mostly fuzzy and vague. Many hands were waved.
Re: Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
My experience:
I have had three 240mm lenses in this class. A Graphic Kowa locked in its barrel, and two Computars in Copal 3s shutters.
All easily cover 7x17" with movements. My current Computar maxes out the rise on my camera (approx3").
All have been sharp in the corners.
The GK was sharper than my first Computar, so I kept the GK.
I just got the second Computar and put it in a like-new Copal 3s. It is sharper than the GK, so the GK will be going.
Oh, and they all easily cover wide open, although I would never shoot them as such.
Re: Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
Potential buyers should look first for direct experience from the seller, not "should" or "could" claims. Secondly they should investigate claims made by people who've actually photographed with said lenses (see above). Finally, they should investigate any changes made over the years on said lenses and what exactly the serial numbers are to get a sense of production timeline.
The lenses in question are expensive. I would love to know if the 240mm could come close to covering 8x20, and if it could I would buy it. I have a 240mm GK like Lachlan above which doesn't quite cover but would cover 7x17 - so if the Computar has a bit more coverage then it could stretch to 8x20...but that is a supposition. If it was cheap enough I would buy it to try it out.
My 305mm G-Claron lens, older Dagor design, covers 8x20 but off-hand one might be "dubious" of that claim. Since I've used it...I can state more firmly. I will have to re-read the ad and see what claims were made and which were actual tested.
Re: Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
12-Sep-2014, 11:34 #101
http://www.largeformatphotography.in...overage/page11
Quote:
Originally Posted by
Dan Fromm
Thanks for posting this John. I've added a link to this page to my list of useful lens-related links...
Some people... Forget more quickly than others.
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Re: Computars, Apo-Kyvytars, puffery and confusion - how quickly we forget
Quote:
Originally Posted by
Corran
Potential buyers should look first for direct experience from the seller, not "should" or "could" claims. Secondly they should investigate claims made by people who've actually photographed with said lenses (see above). Finally, they should investigate any changes made over the years on said lenses and what exactly the serial numbers are to get a sense of production timeline.
The lenses in question are expensive. I would love to know if the 240mm could come close to covering 8x20, and if it could I would buy it. I have a 240mm GK like Lachlan above which doesn't quite cover but would cover 7x17 - so if the Computar has a bit more coverage than it could stretch to 8x20...but that is a supposition. If it was cheap enough I would buy it to try it out.
My 305mm G-Claron lens, older Dagor design, covers 8x20 but off-hand one might be "dubious" of that claim. Since I've used it...I can state more firmly. I will have to re-read the ad and see what claims were made and which were actual tested.
Bryan, Mine is untested. Is your 305 G-Claron like this one? I think this version does not fit a Copal 1 shutter, but I have not tried it. I have no idea about coverage.
Attachment 157093