Componon 150/5.6 for taking lens -- convertible?

[Donald Qualls]

I've just purchased a Schneider Componon 150 f/5.6, in nice working Synchro Compur with accurate aperture scale, for what I think was a good price; this will be used on my recently acquired Aletta 4x5. I'm aware this was originally made as an enlarging lens, but I've also seen references to the Componon and Componon-S as taking lenses; the Componon-S is said to be similar to a Symmar (including, in this length, converting with rear group only to a 265 f/12), and there are many enlarging and process lenses that do work well at infinity focus, especially if stopped down.

My question is, how would I go about testing the front and/or rear groups separately using only film, enlarger, and 2400 ppi scanner? Or is use of the lens in "converted" mode a matter of whether it's "good enough" for my needs? Are there significant optical differences between the Componon and Componon-S that might affect my ability to use the rear group (or the front group, for that matter) in "convertible" form, things like field curvature, coma, etc.?

[Joseph O'Neil]

I have two 180mm lenses, one is a componon converted to taking use, just like yours, the other is an older Sironar. Almost impossible for me to tell the difference on shots taked between the two. unless you see something obviously wrong with the lens, I would go ahead and shoot, see how it works out for you.

good luck
joe

[neil poulsen]

I used a 150 Componon S in a Copal shutter, and it worked great for some photographs taken at just a few feet. I checked with Schneider on this, and they confirmed that the Copal 0 should work fine. I had to work through an f-stop conversion, since my shutter was normally used for a 90mm f5.6.