I own the Kowa 16H, which I have recently received and tested with both a Red Epic, a BMCC and a set of Nikon Ai-S lenses. I found that the amount of barrel reflection on heavy flares caused a very strong yellow vignette. I thought it was my particular Kowa, but then I see the same on several Kowa B&H shots. I have now seen this on all sorts of light from sun light to LED to sodium vapor to fluorescent, from medium taking lenses to tele end. I also hear it is common on other anamorphics.
Is this a known issue, is there anything that can be done about it? Does it happen more to some lenses than others or is it inherent to the design of the anamorphic adapter? It does not seem to happen on an Optex lens I've borrowed.
I've spoken to two lens technicians who say it is either the design or the lack of blacking on the edges of the front element (?)
I would want to use my Kowa but find the usefulness limited with these vignettes occurring anytime it flares.
One thing that comes to mind is to try and add a vignette of my own in post to hide the yellow vignette, but may look to obvious. Will need to do some testing with it.
I will shoot some examples with my lens today as I don't want to offend anyone else by posting their samples.
Would like to get some feedback from people if they have seen this happen and if they have any solutions?
One other forum member mentioned he got this with his anamorphic, and he could reduce (but not eliminate) the vignette with a mattebox.