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Trouble with A7R2 Sony
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PostPosted: Sun May 06, 2018 10:28 pm    Post subject: Trouble with A7R2 Sony Reply with quote

Some new unseen problem came to my A7R2. The pictures upper edge is gradually dark on open aperture, it disappears when diaphragm closed down. If not this, I would say that it is a shutter's problem, but it's not. How can this be explained?

Here are the samples, 200 f3,5 lens, one done with open, another with f5,6 :


#1


#2


PostPosted: Mon May 07, 2018 3:18 am    Post subject: Reply with quote

IMO it's still a shutter problem with shorter exposures. With the diaphragm wide opened the exposure is shorter and the curtains open and close coupled allowing a slit.
With the diaphragm closed the curtains open and close separately. Probably the problem is when the curtains are moving coupled allowing a slit.


PostPosted: Mon May 07, 2018 4:17 am    Post subject: Reply with quote

Vignetting + a slight sag in the adapter?


PostPosted: Mon May 07, 2018 10:06 am    Post subject: Reply with quote

The first photo was taken with 1/6400 shutter speed. My guess is it is a shutter problem. Try using other lenses at that shutter speed. I would expect all lenses will show the same dark band. My A7 does..


PostPosted: Mon May 07, 2018 11:50 am    Post subject: Reply with quote

Thank you. The trouble is the same with all other lenses and stared a couple of month ago. Is it curable?


PostPosted: Mon May 07, 2018 12:40 pm    Post subject: Reply with quote

A quick google search shows some people claiming EFCS to cause the problem. Does turning the electronic front curtain shutter off help in your case?


PostPosted: Mon May 07, 2018 1:49 pm    Post subject: Reply with quote

dickb wrote:
A quick google search shows some people claiming EFCS to cause the problem. Does turning the electronic front curtain shutter off help in your case?


Yes, this is a well known issue in some cases. Try to turn off El. Front curtain... Like 1 small


PostPosted: Mon May 07, 2018 2:28 pm    Post subject: Reply with quote

I did it, it works!

Thank you all!