Can you use Pentax K-mount lenses on a Pentax 645 with an adapter?
Asked 4/20/2013
1 views
2 answers
0
Is there an adapter that lets Pentax K-mount lenses work on a Pentax 645 camera, and if so what type of adapter is needed?
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
13y ago
2 Answers
5
No. Even, if someone would build an adapter it could not possibly fully work.
One normally adapts a lens for a larger format to a camera with a smaller format. Going the other way, as you suggest, would place a lens with a small imaging circle compared to your sensor or film and result in clipped edges. other words you would only the center which kind of negates the purpose of a larger format.
The other number to pay attention to is the flange distance. You can bridge a gap for a lens that requires a longer one but mounting it too far makes such lenses not able to focus past a few centimeters or less than a meter. This would happen if you placed a K-mount lens in front of a 645 mount camera.
Originally by user1620. Source · Licensed CC BY-SA 4.0
user1620
13y ago
0
Generated from our catalog & community — verify before relying on it.
Generally, no. A practical adapter for using Pentax K-mount lenses on a Pentax 645 is not feasible for normal use.
There are two main reasons:
-
Image circle: K-mount lenses are designed for smaller film/sensor formats than Pentax 645. On a 645 camera, they typically would not cover the larger frame, causing heavy vignetting or clipped edges.
-
Flange distance: Adapting lenses usually works best when the lens is designed for a system with a longer flange distance than the camera body. In this case, mounting a K-mount lens on a 645 body would place it too far from the film plane, so it would lose normal focusing ability and may only focus at very close distances.
So while someone could theoretically build a mechanical adapter, it would not fully work in a useful way. In short: there isn’t a practical adapter solution for this setup.
Recommended products
UniqueBot
AI13y ago
Your Answer
Related Questions
Can Olympus OM lenses be used on a Pentax K-r DSLR?
Can Pentax K1000 lenses be used on a Panasonic Lumix FZ18?
Can a Pentax K-mount Sigma 28-300mm lens be adapted to a Nikon D3200?
Can Pentax K-mount lenses be used on a Canon EOS 90D with an adapter?
Can you mount M42 lenses on a Canon EF-S body, and what functionality do you lose?