Old-timers here may remember Chris Jordan wrestling with the same question, way back when. No, he didn't have rigorous comparison tests to back up his final decision either, but FWIW:
http://www.largeformatphotography.in...-which-is-best
http://www.largeformatphotography.in...le-performance
That's exactly the point I was insinuating, Mark ... with 8X10 one is almost always going to
use a small stop, and at f/45 it isn't going to make a lot of difference whether a lens was
made in 1960 or 2010. There are of course other logistical considerations in lens choice,
but most modern lenses designed for this format are probably going to perform well, as well
as quite a few even older lenses.
Yeah that's a good point. I try to stay on the good side of F/45, but have had to go there occasionally. Usually only when trying to get my Nikkor-SW 120 or my Apo-Symmar 210 to cover 8x10, but i am not satisfied with the results.
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http://adamsatushek.com
I'm reminded that when I bought my first 10x8 camera the seller, a Professor of Photography in in the US, told me the lens was useless, had sweparation anmd he'd never used it, he did tell me who was the original owner, turned out he's studied then lectured at the Clarence White School of Photography.
The bottom line was that the Dagor with separation was actually factoty coated and very sharp, the separation was years of poor cleaning piling dirt up around the edges
In real term the quality of results is down to mainly the lenses and your expectations, it's also about understanding potential limitations particulkarly when using early uncoated lenses and using what you feel is most appropriate for what you're shooting.
Ian
Good advice here especially on camera stability. But don't underestimate the effect of film flatness in a standard holder. When I used 8X10 in industrial setups I would use a standard holder but for critical work on highly detailed flat copy I used a specially designed vacuum holder whose film plane was surface ground. That was for extreme work, but one can consider what flatness might be required by just examining the Depth of Focus relationship, D = 2 CN (for no magnification factor) where D is Depth of Focus, C is a COC chosen to be compatible with the desired degree of enlargement and N is the chosen f/no.
For example if C is .020 mm, (20 um) and N is f/32 then the depth of focus will be 1.25 mm (50 mils). Hey almost 1/16 of an inch which is not too bad but you would need that over an 8X10 surface assuming you have determined the center point of focus. In practice this is not so easy. If you want to push the focus limit the sticky, removable tape is not a bad idea and easier than some kind of vacuum apparatus in the field.
When you combine some focus difficulty with a few other variables you can quickly run out of capturing the plane of focus.
Nate Potter, Austin TX
The channel for film in a double dark is specified as 0.3mm, and sheet film is around 0.25mm, so we're talking about 50 microns of play. I don't want to derail this thread, but film flatness is a made-up problem.
One fellow had holders which he modified to have the vacuum provided by him sucking on a tube during the exposure.Originally Posted by Nathan Potter
I've found that glue sticks with the removable glue (water soluble kind) can hold a sheet of film in place. It's only sticky for one sheet, releases easily, and I haven't done any long term tests.
"It's the way to educate your eyes. Stare. Pry, listen, eavesdrop. Die knowing something. You are not here long." - Walker Evans
You don't get it, Ben. The problem is not with the channels the film slides into - it's with
what lies (or doesn't lie) in between. The bigger the film, the greater the problem, esp if
the camera is pointed down or some temp/humidity differential causes it to expand outwards. Why do you think evey copy camera ever made (at least that I've ever seen)
comes equipped with a vac fram for the film? Even film in a conventional holder below an
enlarger will not expose as accurately as when held flat by vaccum. In the field vac holders
are a hassle, but adhesive ones are not if they are intelligently designed. For a number of
years Sinar sold one as a standard option - a bit pricey for what you got, but it certainly
worked!
It's the bubbling in the middle of the holder that looses sharpness, the edges are usually OK. 8x10 is a large floppy piece of film and taping it for even normal, everyday use isn't a bad idea. When you shoot down, copystand style, you pretty much have to tape it or even Aunt Hilda will notice it's not as sharp.
As for the original question, I think an F2, Gitzo giant, and a modern multicoated lens stopped down to the middle apertures is going to be as good as you can get. You might do as well buying three older 1980s Caltars/Symmars/Sironars for $3-400 each and testing them, as I suspect sample variation in lenses probably will help you find the sharpest lens at a reasonable price. Or just pony up for the latest Schneider or Rodenstock (or maybe Fuji) for $1000-plus and know it will be as sharp as the sharpest 1980s lens. You'd be paying that extra for the convenience and confidence.
... Or you'll be paying a premium for a lighter lens in a smaller shutter,
since these are more in demand nowadays than big clunky fast studio
plasmats. But other than sheer portability, smaller lenses with smaller
shutters can produce sharper images - not so much due to the optical
formulae involved - but because smaller shutters vibrate less, and lighter
lenses are easier for the camera to support, esp at long extensions. Just
something to think about in terms of optimization if you need to lighten the
gear up at some point in time.
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