40.5mm Filters

**gordon_l34** · 02-21-2015, 10:49 PM

Hi,

I have just acquired a collection of photography equipment from a deceased estate.
Amongst the filters are three of 40.5 mm diameter filters.
Can anyone tell me what they are for?

PS. I hope this post is in the correct topic.

Regards.

Rimfiredude · 02-22-2015, 01:17 AM

Q lenses are 40.5

stevebrot · 02-22-2015, 09:33 AM

40.5 mm is common for rangefinder camera lenses (Leica, vintage Contax/Kiev, Nikon S). I have several lenses that take that size filter. Be aware that the thread pitch may be different than current standard, depending on the origin and age of the filters.

Steve

Adam · 02-22-2015, 10:01 AM

Originally posted by gordon_l34

Hi,

I have just acquired a collection of photography equipment from a deceased estate.
Amongst the filters are three of 40.5 mm diameter filters.
Can anyone tell me what they are for?

PS. I hope this post is in the correct topic.

Regards.

Those filters are also commonly used on lenses with rear-mounted drop-in filters, such as the FA* 300mm F2.8, other K mount telephotos, and various medium format lenses.

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)

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mikeSF · 02-22-2015, 10:26 AM

i use them for my 25mm

[random image found on the web]

**gordon_l34** · 02-22-2015, 04:37 PM

Hi,
Thanks for that.
Regards.

02-21-2015, 10:49 PM	#1
gordon_l34 Loyal Site Supporter Join Date: Sep 2008 Location: Brisbane, Australia Photos: Gallery \| Albums Posts: 779	40.5mm Filters Hi, I have just acquired a collection of photography equipment from a deceased estate. Amongst the filters are three of 40.5 mm diameter filters. Can anyone tell me what they are for? PS. I hope this post is in the correct topic. Regards.

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02-22-2015, 01:17 AM	#2
Rimfiredude Veteran Member Join Date: Oct 2014 Location: Washington Photos: Gallery Posts: 2,176	Q lenses are 40.5

02-22-2015, 09:33 AM	#3
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	40.5 mm is common for rangefinder camera lenses (Leica, vintage Contax/Kiev, Nikon S). I have several lenses that take that size filter. Be aware that the thread pitch may be different than current standard, depending on the origin and age of the filters. Steve

02-22-2015, 10:01 AM	#4
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,608	Originally posted by gordon_l34 Hi, I have just acquired a collection of photography equipment from a deceased estate. Amongst the filters are three of 40.5 mm diameter filters. Can anyone tell me what they are for? PS. I hope this post is in the correct topic. Regards. Those filters are also commonly used on lenses with rear-mounted drop-in filters, such as the FA* 300mm F2.8, other K mount telephotos, and various medium format lenses. Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

02-22-2015, 10:26 AM	#5
mikeSF Pentaxian Join Date: Jan 2009 Location: East Bay Area, CA Photos: Gallery Posts: 6,622	i use them for my 25mm [random image found on the web]

02-22-2015, 04:37 PM	#6
gordon_l34 Loyal Site Supporter Join Date: Sep 2008 Location: Brisbane, Australia Photos: Gallery \| Albums Posts: 779 Original Poster	Hi, Thanks for that. Regards.