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02-05-2014, 08:30 AM   #1
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Focal length reducer for 645 lenses

Do you think anyone would be interested? Something similar to metabone adapater for nex.

02-05-2014, 09:56 AM   #2
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It should be possible at least but I'm not sure there's a huge marker for it. It would only be interesting for a relatively small Pentax user group and the lenses available aren't the cheap nor do they really bring much new to the table.
02-05-2014, 10:02 AM   #3
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Theoretical, it will be interesting, especially for a future FF camera. But practical, the 645 lenses are quiet expensive, and big. And it seems to me that for many forum members the most important criterion is the size of the lens. Personally, I don't understand that, but I am a relatively big guy, with big hands, and accustomed with heavy things.
02-05-2014, 11:25 AM   #4
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It would definitely be interesting, especially for people who already own lenses/cameras of both formats. But as stated, the main problem is that MF lenses are a niche, pretty big and not very cheap to begin with. A focal length reducer makes more sense when going from FF to a smaller sensor, because the FF lenses are very common and come in all shapes and sizes
I also wouldn't expect this to be done by Pentax, just look at how long it took them to make that 1.4x TC! But it would be an interesting tool, no doubt. Especially for someone using a Kmount camera, while investing in Medium Format lenses, and then finally upgrading to a MF body later

02-05-2014, 11:47 AM   #5
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The problem is that 645 lenses are not really that special regarding focal length... You only buy them for 35mm or APSC cameras when you need more focal length, otherwise what's the point?
02-05-2014, 12:13 PM - 1 Like   #6
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Here's a crazy idea

It might make more sense for someone to develop a focal length reducer to go from K-mount to Q-mount, given that K-mount lenses are so cheap and plentiful. On the other hand, K-mount bodies are still in production and relatively cheap compared to other bodies in the industry/market, and the Q sensor/body doesn't bring anything new to the table, so I can't see why anyone would actually buy such a beast. Those who buy the Pentax K-to-Q adapter are doing it for the 5x crop factor.

Perhaps for video. Smaller sensors generally support faster frame rates and less rolling shutter. And a focal length reduction of 5x would collect so much more light than the Q 01 prime.
02-05-2014, 12:38 PM   #7
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QuoteOriginally posted by Tanzer Quote
It might make more sense for someone to develop a focal length reducer to go from K-mount to Q-mount, given that K-mount lenses are so cheap and plentiful. On the other hand, K-mount bodies are still in production and relatively cheap compared to other bodies in the industry/market, and the Q sensor/body doesn't bring anything new to the table, so I can't see why anyone would actually buy such a beast. Those who buy the Pentax K-to-Q adapter are doing it for the 5x crop factor.

Perhaps for video. Smaller sensors generally support faster frame rates and less rolling shutter. And a focal length reduction of 5x would collect so much more light than the Q 01 prime.
Is not a crazy, but a good idea.
02-05-2014, 02:39 PM   #8
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K to Q makes much more sense.

02-05-2014, 03:58 PM   #9
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QuoteOriginally posted by Tanzer Quote
It might make more sense for someone to develop a focal length reducer to go from K-mount to Q-mount, given that K-mount lenses are so cheap and plentiful. On the other hand, K-mount bodies are still in production and relatively cheap compared to other bodies in the industry/market, and the Q sensor/body doesn't bring anything new to the table, so I can't see why anyone would actually buy such a beast. Those who buy the Pentax K-to-Q adapter are doing it for the 5x crop factor.

Perhaps for video. Smaller sensors generally support faster frame rates and less rolling shutter. And a focal length reduction of 5x would collect so much more light than the Q 01 prime.
The pixel density of the Q added with the degradation of the converter would probably no result in too nice results.
My guess....

Normal viewing would probably be ok though
02-06-2014, 12:44 PM   #10
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So... a 50mm f2 would become a 9mm f/0.3 or something?
02-06-2014, 05:00 PM   #11
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I think that calculation is about right!
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