Is it pointless to load a Schneider Componon S. 210mm backwards on a 8 x 10 camera?

[David Roy]

Is it pointless to load a Schneider Componon S. 210mm backwards on a 8 x 10 came ra? I recall this was done in a magazine, but I cannot remember which. It was a few years ago.

How does it compare with a 'normal' lens.

I ask because using a normal lens as an enlarging lens is a bad idea because of field curvature. But what about this the inverse?

[Paul Schilliger]

Would the image circle be enough when lens is set at infinity?

[Pete Andrews]

At half size and above it'll cover, and give you better definition than a standard lens.My own experience is, that it isn't necessary to reverse enlarging lenses for macro use at around 1:1.

[neil poulsen]

I would like to add a little to this question. Does image quality really depend on which direction the rays are travelling? Keep in mind that a Componon-S is, more or less, a symmetrical lens. Or does it have to do with the fact that the front element of this lens is larger than the rear element? If the latter, doesn't it make sense to have the larger element facing the larger surface, whether it be the negative or the object being photographed?

I used a Componon-S to photograph a painting that was roughly 2'x3' and got great results. I did not reverse the lens.

[David A. Goldfarb]

You would only reverse the lens for macro use beyond 1:1.

Normally, the rear element is close to the film and the front element is far from the subject. Beyond 1:1, the situation is reversed (i.e., the subject is nearer than the film), so you can take better advantage of the corrections designed into the lens by reversing it (so long as it isn't a macro lens).

[Bruce Wehman]

David,

Most enlarger lenses are optically formulated for the 1:5, 1:20 range of enalrgement. Reversing one on an 8x10 would give you optimum results if you were filling the frame with a stamp or a coin. With that much bellows draw, the coverage should be adequate and the resolution would be superior to a normal lens (one formulated for infinity). For 3 dimentional subjects, yes, it is quite piontless (unless you are trying for something arty) because depth of field in that situation would be about zero.

[David A. Goldfarb]

That's fair. I tend to do macro work, occasionally with reversed enlarging lenses for large magnifications, in medium format or 35mm.

[David Roy]

Thanks Paul, Pete, Neil, Bruce and David. I'm just being as thrifty as I can and want one lens to do it all :)

I want to get into large format but I do also need an enlarger. So, apparently I can get along with a single enlarger lens.

Also, I primarily want make negative copies of medium format and 35mm for safe keeping and special effects.

Would you recommend instead I get a 'normal' large format lens and use it as an enlarging lens? Field curvature won't bother me to much at this point, unless its severe. I have several enlargments I did from 35mm at a school lab and the corners are not in any way sharp and I do like the prints.

[Jeff Buckels]

Think about the older apochromatic copy lenses (Goerz Apo-Artars, Wollensak Apo-Raptars, Zeiss Apo-Tessars ...). Yes, all are "optimized for 1:1". This means that there is fabulous correction at 1:1 only and that the lenses are merely outstanding otherwise. Much in the category would be single-coated or not coated. Single-coated is great (much more important breakthrough than multi-coating). These kinds of lenses can be had on ebay for very reasonable prices. Go to "large format" and search "lens".... BTW, if this 210mm FL is real germane, think of the venerable Schneider Symmar 210 convertible (remove the rear element and it's 370mm). Classic plasmat design, typically (always??) single-coated in Synchro-Compur. Not hard to find on ebay.... jeff buckels (albuquerque nm)

[Jim Galli]

FWIW....I have a modern 135mm componon that came to me via Ebay for about $2.50. Not needing another enlarger lens, I mounted it in a Copal 0 facing forward, and use it as my primary taking lens in that size. I always stop down to at least f16 1/2 because of the correction being not optimum, but I was stunned at the results. It is incrdibly sharp for buildings etc. I might not choose it for the loooong distance pano's, but for things reasonably near it's fabulous.