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08-21-2014, 03:19 PM   #106
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QuoteOriginally posted by Thomas Quote
Coincidentally I just did the same comparison and included the Z. I agree the A7r was surprising good , but I also think there is a focus issue with the 645D image. Notice the artificial leaves to the right of the Samuel Smith bottle: the texture is clearly visible in the D image but not the Z or the A7r, indicating the focus for the D is a bit further back than the others; additionally, the 75mm was used for the D, with somewhat less DOF than the 50 and 55mm used for the A7r and Z.
Since the 645 lens is using a 75mm as well as a much larger sensor, this makes for a substantially thinner focusing plane. That being said, this doesn't affect our ability to compare the in focus regions. And so, I tried to focus on those selected areas in my comparison.

That being said, I'd also add that the 645D with it's larger photosites still holds the advantage in terms of file integrity. Which becomes apparent when either blowing up or push processing the images. Though at 1:1, I'm tempted to say the A7r files show better DR characteristics in all area safe the red channel. Which the 645D is clearly dominating the field.

08-22-2014, 05:17 AM   #107
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QuoteOriginally posted by beowulfAgate Quote
I know this is off topic of the thread but honestly I am not sure what it is if I've got a bad model off the assembly line or what but I've seen shutter vibration in some, not all, but some, of my images that were shot even at 1/320 of a second. It is a very distinct look that I recognize immediately-the "sharpest" part of the image is where the focus was, but deteriorated. The first time I took the A7r out of the box was on a vacation in March. Had NO IDEA about the shutter shake issue whatsoever as I had bought the camera solely based on the stats and it arrived the day I left. Shot images I would have shot with any other camera from 1/80-1/160 of a second. Almost half, if not 75% of my images were lacking any sharpness whatsoever...over 350 images. I had NEVER seen this before so I did the research and bam there was the shutter vibration at the top of a Google search.

The images I have taken, all handheld, from 1/200th of a second and faster, will show in most shots that vibration effect. I cannot get the tack sharp effect people claim to see. If I use a tripod, I can achieve a nice sharp image, but I mean, if I can't get that standing still, holding the camera with both hands, not walking or moving, and using a shutter speed of at least 1/200th, auto ISO, f/stop between 5.6 and 8, well, I just don't think it is worth it. Again, this is just my personal experience.
A7r with 70-200mm F4 handheld @ 200mm F4 & 1/320 sec
08-25-2014, 06:43 AM   #108
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Very nice photo! Again, I think maybe it's just something wrong with my model or something? I took a photo in some fog of a cooler sitting alone on a beach at 1/320 of a sec. early AM. I was shooting with the Leica Tri-Elmar @ 18mm. The focus was on the cooler however the edges of said cooler exhibit a "ghosting" where it seems to be moving from right to left. And this was at 1/320. I'll try to post the photo to flickr soon. Anyways, I am happy to be back to the more manual, simple aspects of the 645 system.
09-11-2014, 07:58 AM   #109
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Just caught up with this thread... and I have a couple questions...

Can anyone discuss the "camera shake" issue on the A7r... is there some kind of "shake issue" that would affect tripod users? For myself, I would use this camera for landscapes, and I don't care much about hand held, I have a K-3 with shake reduction for that. I'm more concerned about sunrises and sunsets etc. where DR is really valuable.

The big issue for me right now, is I bought a 645 film camera, and I never take it anywhere, it's too big. So , now I'm looking at something I can take along and use for landscapes, in my K-3 bag. It pretty much goes without saying, if Pentax releases an FF, it's not going to have the skinny form of an A7r, so I suspect I'd actually prefer the A7r to a Pentax FF for my use. For me, it's all about, my camera bag is already heavy, and the more I add to it, the more I have to leave home.

While I'm happy to concede that I'd be happier with 645z or 645d images, I can't be happier with them if I always leave the camera home.

I've read through
https://www.pentaxforums.com/reviews/sony-a7-with-pentax-full-frame-lenses/introduction.html

And I'm interested to note that an A7 produces not much benefit, but the A7r doesn't seem to be much discussed unless I minded something.

IR tells me I can get much clearer images with an A7r...

100 ISO


3200 ISO


But it doesn't in any way tell me what I'd expect with Pentax glass, which I would still be using.

I've noticed that with cameras designed for a short registration distance, results using long registration glass, do not always produce as good results.


Last edited by normhead; 09-11-2014 at 09:25 AM.
09-23-2014, 09:29 AM   #110
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QuoteOriginally posted by normhead Quote
I've noticed that with cameras designed for a short registration distance, results using long registration glass, do not always produce as good results.
Adapters are usually not designed very well. Reflections are the norm, and on some I'm not even sure if they're light-tight.
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