Petri 2.8 Color Corrected filter size: Does anyone know the filter size of the Petri Orrikor 45mm f/2.8 lens? I measured the filter ring with a metric ruler (not a caliper) and it...

StanMac Loc: Tennessee

Does anyone know the filter size of the Petri Orrikor 45mm f/2.8 lens? I measured the filter ring with a metric ruler (not a caliper) and it appeared to be about 41mm but I cannot be certain.

Thanks for any information you can provide.

Stan

DavidPine Loc: Fredericksburg, TX

I started with a Petri 2.8 in 1963 in Vietnam.

rook2c4 Loc: Philadelphia, PA USA

According to the chart on this page, it appears the filter size is 40.5mm.
http://www.photoethnography.com/ClassicCameras/index-frameset.html?PetriColor35.html~mainFrame

For filter sizes, 40.5mm is far more common than 41mm. In fact, I don't think I've ever encountered a rangefinder camera whose lens took 41mm-sized filters. Certainly none of my cameras do!

RWR Loc: La Mesa, CA

StanMac wrote:

Does anyone know the filter size of the Petri Orrikor 45mm f/2.8 lens? I measured the filter ring with a metric ruler (not a caliper) and it appeared to be about 41mm but I cannot be certain. Thanks for any information you can provide. Stan

The lens that rook2c4 referenced is the 40 f/2.8, while yours is the 45 f/2.8. If you have accurately measured the thread ID as 41mm, I believe the correct filter size is 41.5mm, a fairly common size at the time.
Edit: If your measurement seems to be a bit less than 41mm, the actual thread could very well be 41mm, which is apparently not so uncommon. I have a Topcon extension tube set with 41mm threads and use a 41-52mm Heliopan #615 step-up ring with a 52mm reverse ring for some macro work with my Exaktas.

StanMac Loc: Tennessee

Thanks for your help. A quick search online revealed that 41.5mm filters are scarce as can be. The solution appears to be a readily available 41.5 to 43mm step-up ring - 43mm filters seem to be more available. Thanks again!

Stan

RWR Loc: La Mesa, CA

StanMac wrote:

Thanks for your help. A quick search online revealed that 41.5mm filters are scarce as can be. The solution appears to be a readily available 41.5 to 43mm step-up ring - 43mm filters seem to be more available. Thanks again!Stan

If you also want a screw-in lens cap and hood, they may not be available in 43mm. In that case you might want to get a 41.5-49 or 52mm step-up ring. Those caps, filters and hoods are readily available from many sources.

jerryc41 Loc: Catskill Mts of NY

rook2c4 wrote:

According to the chart on this page, it appears the filter size is 40.5mm.
http://www.photoethnography.com/ClassicCameras/index-frameset.html?PetriColor35.html~mainFrame

For filter sizes, 40.5mm is far more common than 41mm. In fact, I don't think I've ever encountered a rangefinder camera whose lens took 41mm-sized filters. Certainly none of my cameras do!

Half a mm? I'd like to know the design decision behind that. : )

Lots of choices -

https://smile.amazon.com/s/ref=nb_sb_noss_2?url=search-alias%3Daps&field-keywords=40.5mm+filter