Pentax 67 45mm f4 (late) and vignetting

Hi all: I'm considering acquiring the 45mm f4 lens (late model) for my Pentax 67II kit. I don't have any 82mm filters but I do have a couple of 95mm B+W filters (81A and polarizer) for the two zooms in the lineup. What is the likelihood of any vignetting if I were to use them on the 45mm with a slim-profile step-up ring? Anybody have any experience with that? Thanks in advance!

dscottjorgenson said:

Hi all: I'm considering acquiring the 45mm f4 lens (late model) for my Pentax 67II kit. I don't have any 82mm filters but I do have a couple of 95mm B+W filters (81A and polarizer) for the two zooms in the lineup. What is the likelihood of any vignetting if I were to use them on the 45mm with a slim-profile step-up ring? Anybody have any experience with that? Thanks in advance!

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I have a 45mm f4 and have used it with 82mm filters with no vignetting. I would not anticipate any from a larger filter especially if you are using a low-profile step-up ring.

No vignetting with this lens using its native 82mm slim profile filters, but a check of vignetting needs to be made in your case by fitting the step-up ring with the TTL or focusing prism removed. You then have a view of the entire focusing area — a much better assessment than relying on the cropped 92% view which can in some cases obscure vignetting. Keep filters to the low-profile style on the SMC Pentax 67 45mm f4; some B+W filters e.g. the thick-ringed, older style F-POLs, can cause vignetting on wide angles. I use NiSi True Colour very low profile filters.