Leica User Forum - View Single Post - Vignetting on CV 15/4.5 with Milich filter holder

wmspa · 09/04/07, 10:03 PM

I tried again, having in mind Geoff's comment, both with a Leica filter and a Heliopan filter. With the Heliopan filter, the adapter cannot be fully pushed onto the lens shade, because this filter is a bit larger than the Leica filter. The vignetting was about the same as when I used the adapter without any IR filter - although logically it should be stronger. With the Leica filter, the position of the adapter was identical to that when the adapter is used without filter - and the vignetting was almost gone. There was just some tiny vignetting left in the corners, which an improved CornerFix profile should be able to deal with.

So the essence seems to be that the Milich adapter works fine as long as a Leica IR filter (or another IR filter of the same size) is used, but may cause vignetting if used "stand alone" (strange!) or with Heliopan filters. Maybe also some slight variations in the CV 15's focal length may cause a difference.

If someone has an explanation why there is less (or no vignetting) when an IR filter is used ... should be interesting news. Unlike Geoff thought, it's not the wobbling when no IR filter is mounted, because the vignetting was apparent in all four corners, not just in one or two corners as one would expect when the holder is not sitting straight on the lens.

Thanks for your help!

Wolfgang

09/04/07, 10:03 PM	#11 (permalink)
wmspa Neuer Benutzer Join Date: 09/19/06 Posts: 22	AW: Vignetting on CV 15/4.5 with Milich filter holder I tried again, having in mind Geoff's comment, both with a Leica filter and a Heliopan filter. With the Heliopan filter, the adapter cannot be fully pushed onto the lens shade, because this filter is a bit larger than the Leica filter. The vignetting was about the same as when I used the adapter without any IR filter - although logically it should be stronger. With the Leica filter, the position of the adapter was identical to that when the adapter is used without filter - and the vignetting was almost gone. There was just some tiny vignetting left in the corners, which an improved CornerFix profile should be able to deal with. So the essence seems to be that the Milich adapter works fine as long as a Leica IR filter (or another IR filter of the same size) is used, but may cause vignetting if used "stand alone" (strange!) or with Heliopan filters. Maybe also some slight variations in the CV 15's focal length may cause a difference. If someone has an explanation why there is less (or no vignetting) when an IR filter is used ... should be interesting news. Unlike Geoff thought, it's not the wobbling when no IR filter is mounted, because the vignetting was apparent in all four corners, not just in one or two corners as one would expect when the holder is not sitting straight on the lens. Thanks for your help! Wolfgang