Well, I have not used the Contax, but I did shoot my Voigtlander SC Skopar 21mm f4 on a Kiev 4a. Since we are allowing Kievs (which are Contax's or derivatives in later models), I thought I would add a few shots. Basically, I wanted to photograph Prado dam. It is very wide, and I can be close or very far (going back drops off and there are obstructions). I tried my Mamiya C330f with the 55mm f4.5 lens close-up, and it just was not wide enough (I did create a
composite shot from 2 negs). As a back-up I brought the Kiev 4a and SC Skopar 21mm, and was able to get the whole dam pretty close with no issues. It is not as high resolution, but still a decent shot. In both cases (120 and 135) I used Ilford Delta 100 developed in ADOX FX-39 II.
Prado Dam whole by
Mark Wyatt, on Flickr