This thread discusses the Content article:
Cosina-Voigtlander 35/1.7 Ultron Review
Thanks for the review, Brian. Excellent as always and very useful as it's from a user's pov. I love my Ulton and use it frequently for street shots. When I first got it I noticed the same vignetting that you mentioned on one roll of Ektachrome. However, since then it has not reappeared. I can only guess that it shows up at a particultar f-stop, distance combination. Unfortunately, after using the lens extensively on a shoot a few weeks ago, the barrel is now loose. So I'll soon be making use of your other excellent article on Ultron repair.