150mm G-Claron Sharper than 180 Componon-S?

[John Layton]

Amazing...in very carefully examining center and edge detail in a 20x30 print made with a 180mm Companon-S, and the same print as a 30x40 made with a 150mm G-Claron...the Claron wins! How is this possible? And the Claron, to boot, has an amount of dust in between elements which might be cause for some concern. Companon-S Stopped to f/16, Claron to f/22. Heiland LED VC light source. Go figure!

[Drew Wiley]

It makes sense. I've done comparison tests. But bring something like an Apo Rodagon N into the contest, and it's another story.

[Paul Ewins]

Unless you are testing multiple copies of each lens sample variance will come into play. You may have a better than average G-Claron or a worse than average Companon-S or both. There is no guarantee that repeating that test with two other copies of those lenses would have the same result at all.

[Drew Wiley]

Sorry... Paul not Pere.

[Drew Wiley]

Gosh, Pere, you really think Schneider was that sloppy with quality control! The difference he is seeing is inherent. G-Clarons were designed for close-up flat work, though they also excel for general photographictaking. I'm referring to the plasmat versions in shutter. But G Claron we're also marketed in barrel, and differ from enlarging lenses only with respect to a smaller maximum aperture.

[Paul Ewins]

Gosh, Pere, you really think Schneider was that sloppy with quality control! ...

The Schneider QC was 40+ years ago, anything could have happened since. Even when new you will still get some lens that barely make it past QC, most that breeze through and some that are exceptional. If that variability didn't exist then there would be no need for QC.

[neil poulsen]

What was the distance between the camera and subject matter?

[neil poulsen]

What was the distance between the camera and subject matter?

Oh I see; this was for an enlargement. Interesting.

I see that the G-Claron's aperture was f22, although the Componon's aperture wasn't that far off.

Don't know about G-Clarons, but the ideal aperture for Rodenstock process lenses is f22. If the same is true for G-Clarons, that might help explain what you're seeing.

[Luis-F-S]

Oh I see; this was for an enlargement. Interesting.

I see that the G-Claron's aperture was f22, although the Componon's aperture wasn't that far off.

Don't know about G-Clarons, but the ideal aperture for Rodenstock process lenses is f22. If the same is true for G-Clarons, that might help explain what you're seeing.

Neil I'd be curious how the 180 Apo-R fares! I know you and I have one; my 150 G-C which I bought new has developed some coating issues, so I don't think it's usable. L

[John Layton]

Both lenses used to enlarge from 5x7 negative...Companon-S to 20x30, G-Claron to 30x40. Companon-S is perfectly fine...but G-Claron excels despite greater magnification. No big deal...just a bit surprised.