Quality 8x10 gear...how much does it matter?

[John NYC]

The way I look at it, I'm spending around $20 per color negative, so I might as well do the best I can. I have been pleased with my Caltar, but am just curious whether I would get better results with a different lens.

From my own limited field comparisons of the lenses I have owned, my conclusions are that the differences among most modern lenses are very small, but I would say that corner sharpness has varied the most among them. I believe the best lens I have owned so far with sharpness across the entire frame is my older Fujinon W 250mm f/5.6 (the single coated one with the inside lettering). Maybe I just have a great sample of that one and I had less good samples of other lenses? As another generalization, I would say my Copal 3 lenses have been slightly slightly less sharp than those in smaller shutters, but they also have seemed more "smooth" in some way that was most pleasing. Ultimately, I got rid of the larger lenses to favor weight in my backpack.

[Chris Strobel]

Astronomers use glass plates because they are flat and can be accurately positioned.

Big instrument like the Anglo Australian and Hale scopes yes, images from smaller instruments, the likes of whose photos graced the covers of periodicals like Sky & Telescope for years no.I worked quite a while for Astrotrak Engineering back in the day making mounts for everyone from advanced armatures up to instruments used for site testing the Cerro Tololo Inter American Observatory in Chili.Of course CCD's killed film in astrophotography long before they hit our dslr's.

[Ben Syverson]

If you focus with dollar store spectacles and use a wobbly tripod, you are correct - film flatness will never be an issue.

Glad that doesn't describe me, then.

[Drew Wiley]

I've got some Sinar literature around explaining why the weakest link in focus with modern
camera and lenses is the uneven film plane caused by the conventional holder itself. This
is not a guess for anyone who has actually experimented with the difference. 8X10 film
has a tendency to bow in a conventional holder. I've had to discard shots made with ordinary holders because they weren't sharp enough for big enlargment (or reserve them
strictly for small prints). People have different standards, but given the original question
regarding optimization, this is a significant and real factor, a FACT. Sorry if certain people
keep scooping BS to serve up, but they apparently have a very loose concept of sharpness.

[adam satushek]

[QUOTE=michael slade;858063]Ha! I also have a Canham 8x10, a bunch of G-Clarons and some longer process lenses. I am totally tongue-in-cheek in my last comment.

Michael I see now that you were being sarcastic....for some reason when I was looking at this thread last night your image didn't show up.....makes much more sense now....

[adam satushek]

Thanks everyone, I'm sure my lenses are sufficient. Ill probably still pine over the Sironar-S's (240, 300, and 360mm), as well as the Schneider 600/800 Apo-Tele-Xenar.......but luckily i cannot afford any of these now. My money would be better spent on a few more film holders, some double sided tape, and a bunch of Portra 160.

Drew, out of curiosity how have you modified your film holders for optimal flatness? Would you recommend the double sided tape or glue stick approach too?

[Drew Wiley]

You start with a conventional plastic Lisco or Fidelity holder and carefully cut away flush
the fins of each side holding the film in (obviously not the part that holds the darkslide).
A straightedge, steady hand, and sharp utility knife are all that is needed. The film should
press directly in rather than slide in. Then you need the repositionable version of 3M ATG
tape which is permanent adhesive on one side (facing the septum) and reusable Post-It
adhesive on the side facing toward the film. You apply parallel strips lengthwise. I wouldn't
use an ATG gun. There should be no bubble, ripples, or bit of leftover adhesive. It's fairly
straightforward and the tape should work for maybe a thousand film changes if not stored
in a hot area. Be careful not to get dust on the adhesive during film changes. Might be a
good idea to practice first on a funky old holder. I believe the correct tape is 3M no.928,
but you might want to double check that.

[adam satushek]

Thanks for your response Drew! It seems fairly straight forward but, the adhesive loosening in hot weather does make me nervous. With the film channels gone the film would be loose if the adhesive released. This seems like a great solution to shooting straight down especially in a studio environment, but may not be ideal for the kind of situations I tend to shoot in. I will try the simpler double sided tape method first and rely on this more extreme method if i feel the film needs to be even flatter, or if I ever have to shoot straight down.

Thanks!

[Drew Wiley]

Adam - do not use conventional double-sided tape. You'll regret it. The specific ATG tape
I referred to (repositionable) does not lift or blister from its permanent side. Improper storage might instead limit the useful life of the repositionable side. I have used this system for maybe twenty years without changing the tape - all kinds of weather, in the
desert, up in the high country and snow, etc. I'm an outdoor photographer. It's a very thin tape with an excellent track record. The same product Sinar used when they asked $600 per holder (though they had rectangular sections custom cut rather than parallel strips). It will make a real difference even shooting level.

[Chris Strobel]

You start with a conventional plastic Lisco or Fidelity holder and carefully cut away flush
the fins of each side holding the film in (obviously not the part that holds the darkslide).
A straightedge, steady hand, and sharp utility knife are all that is needed. The film should
press directly in rather than slide in. Then you need the repositionable version of 3M ATG
tape which is permanent adhesive on one side (facing the septum) and reusable Post-It
adhesive on the side facing toward the film. You apply parallel strips lengthwise. I wouldn't
use an ATG gun. There should be no bubble, ripples, or bit of leftover adhesive. It's fairly
straightforward and the tape should work for maybe a thousand film changes if not stored
in a hot area. Be careful not to get dust on the adhesive during film changes. Might be a
good idea to practice first on a funky old holder. I believe the correct tape is 3M no.928,
but you might want to double check that.

Drew is this the stuff? http://www.findtape.com/shop/product...00&height=1074 Would you happen to have a picture of your holder so we can see exactly how you laid out your strips? I have an old beater Lisco holder I'm going to try your method with.Thanks for sharing it.

Chris