The Pentax645 35mm F3.5 is considered one (if not THE) sharpest and widest manual focus 645 lens for pentax, but unfortunately it is also $500+ used on ebay, (a "slightly" more expensive 25mm lens exist for the new digital 645 @ $5500 new) so instead here is a review of the Pentax 45mm f2.8 which I got used from ebay @ ~$70 :D
Its is a fairly small lens, but still about double the length of the 75mm. It comes in a 400g, and with a 3rd part light weight metal 67mm thread open lens hood from amazon, it becomes a really nice 68mm FOV F.2.8 lens and easily fits in my walk around everyday shoulder bag.
And with the metal lens hood, I don't need to fiddle with front cover, and will just place it in bag as is, feeling confident that nothing will get scratched.
Here is what I am doing to try and get comparable results. I.e consistent setup
- Level and 90degrees shooting for even length to focus plane and the setup.
- Same framing for all lenses. I.e longer focal length will be shot from further away to achieve same framing. (see images below)
- Lighting is done by softbox and flash to eliminate any motion-blur.
- ISO50 for low noise, 1/200sec shutter and exposure adjusted through flash.
- Shot tethered into CaptureOne Pro 9, with only White balance, CA and Crop adjustment - No additional sharpness added. exported to 100% quality Jpeg in sRGB at 2048px wide.
Above shots are f2.8, f4, f5.6, f8, f11, f16
Below is a 100% crop for pixel peeping, please open the image in a new window or download to see in full size.
Here are some boring, but real-life photography samples from a day with dreary weather. (memo to self; redo some shots here because, damn! they are boring)
Being too soft wide open at F2.8, but stopped down to 5.6 it really shines and is quite sharp. For landscape with a tripod I am sure this will produce some nice images, but handheld as a walk around lens I find it too slow even with the IBIS of the Sony A7RM2. But is a nice size, lightweight, smooth focus and at a nice prize. Certainly it is well worth the $70 I paid. :)