Discussion in 'Sony Alpha E-Mount Cameras' started by hknymz, Jan 15, 2014.
Photos taken by SMC Pentax K 200 mm f/4 , some darkness have on corners . Is it adapter issue ?
It might be adapter or the lens. It is hard to tell. Most of the lenses esp on full frame vignette. Usually you need to stop down to reduce it.
How does the lens perform on a Pentax body?
I was searching for reviews, but all Pentax dslrs are apsc sized, no ff... Sb using on film might help...
I dont use this lens on any pentax body.
Sent from my GT-N7000 using TalkEmount mobile app
Do you have this issue with any other Pentax lenses? Is it a fairly cheap adapter? I don't know much about camera engineering, but as a guess, I don't think adapters would cause vignetting. Crappy adapters might cause focus issues due to faulty flange distance.
An adapter would cause vignetting if the "throat" wasn't wide enough. Since the NEX cameras are all APS-C, it is quite possible an adapter was not designed with full-frame in mind.
I have heard that the Hawk's helicoid adapter for M-mount needs to be version 3 to work correctly on full frame. I believe it - I have an older version and I know the barrel of the helicoid was smaller than the opening of an LTM or M-mount, but was more than large enough to let lenses cover the APS-C NEX sensor.
Vignetting can also come from a filter. If you had a filter on the lens, try taking some shots with the filter removed and see if that changes anything.
I'm using a Kippon adapter for Nikon to NEX, and I haven't run into any vignetting issue that the native lens itself doesn't already have.
Maybe it's the adapter, should 200mm on FF have any issue with vignetting?
BTW I like the look with the vignetting on the bird shot
Does the vignetting lessen when you stop down? If it does, I'm assuming it's the lens, if not, it's probably the adapter.
i will try tomorrow all suggestion
Separate names with a comma.