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Author Topic: Sony A7r questions  (Read 30912 times)

BernardLanguillier

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Re: Sony A7r questions
« Reply #40 on: December 16, 2013, 06:19:38 PM »

Too bad, I use the 180mm f2.8 APO a lot on the D800 for distant pano stitches since those Leica R APO lenses are optimized for that very application. It looks like Sony didn't quite fully validate all the usage patterns here.



Cheers,
Bernard

philbond87

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Re: Sony A7r questions
« Reply #41 on: December 17, 2013, 10:02:23 AM »

I returned my A7R because of two problems that are each show stoppers for me.

1. The file compression applied to the raw files is lossy. Artifacts are clearly visible at 100 percent view as sort of an egg shell stipple on surfaces that should be smooth. While this would be unlikely to show in a print up to native size (and actually might help smooth transitions while maintaining a sense of surface), heavily working a file in Lr and Ps will make it worse and visible in prints. Tonal banding is also likely in more extreme cases since these are essentially 8 bit files.

Did you experience those issues yourself?
I've been using an a7R for over a week now, both hand held and on a tripod, and haven't had an issue with the shutter causing vibration.
I don't mean to suggest that it's not a problem others have seen but I certainly have not yet seen it.
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peterottaway

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Re: Sony A7r questions
« Reply #42 on: December 17, 2013, 07:07:26 PM »

There is also the basic human psychology at play here as well as the maybe buyers remorse.If its not your brand be it cameras, cars or whatever - what is an annoyance to be worked around on your favorite becomes an unacceptable problem on a competitors equipment.

I use tripods for up to half my photography and accept that to get the best possible results from a 36 MP sensor your technique is required to to top notch in all respects.I only received my A7r on Monday ( it was 44.7 C) and due to all the real demands of life I haven't yet been able to do more than a few basic shots.

Also I don't think there is a camera,lens,tripod combination that doesn't have a shake problem somewhere in its speed range. With some it appears to be more of a problem at 1/8 to 1/15 whilst others are worse at 1/30 to 1/60 of a second.
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David Campbell

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Re: Sony A7r questions
« Reply #43 on: December 20, 2013, 06:46:52 PM »

I have yet to put my A7R with metabones Canon EF III adapter through its paces yet.
Here are some things I have noticed about both the camera and the adapter

Metabones Canon EF III Adapter
1. My adapter bore diameter was so tight, that I had to take the lens mount off the adapter and sand the chrome plating off the brass to increase the bore diameter. Once I had done this, I was able to fit Canon lenses with out forcing them on and having fear that I would break the lens mount trying to get the adapter off the lens. This tight fit was not due to the springs as it mentioned on the Metabones website.

2. The button on the adapter, that I had assumed to be DOF preview is actually the reverse! If a camera has stopped the lens down, pressing the button apparently makes it wide open.  Not so useful for my photography.

Sony A7R
1. As previously mentioned, no first curtain shutter. I am yet to test to see if this will be a true issue for the focal lengths and shutters speeds I typically shoot at.
If there was the ability in Manual mode, to disable the full time live view, then this would reduce the close/open shutter vibration if the sensor /hardware design can not allow for a firmware update for electronic first curtain shutter.

2. No real time RGB histogram, only a luminosity histogram that appears to be just a copy of the green channel.
During image playback, you can get a split LRGB histogram and it appears that L=G channel.
I have not yet tested if the zebras are based on the first channel to clip or this luminosity channel.  I fear the luminosity channel.

3. No DOF preview button.
Without this feature, using my TSE24 is difficult to set the plane of focus to maximise DOF.
I tried a walk around which involved the following:
- Take a long shutter speed shot at the desired aperture
- Mid shot decouple the lens and adapter pins by rotating the lens on the mount.
  Be careful not to rotate too much and have your lens fall off. (red dot is near the EF-S white dot)
  This will leave the lens stopped down
- Use  the TSE rotation axis to rotate the tilt plane to the desired tilt axis (one detent stop)
- Set your plane of focus and if happy, securely mount the lens and rotate back to the proper position.

As I said I have not tested the kit out properly yet, just in my lounge room last night after modifying the adapter.
Over the Christmas break I will get and use it for landscape work and report back anything else I notice

Regards
David

philbond87

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Re: Sony A7r questions
« Reply #44 on: December 20, 2013, 11:42:13 PM »

David,

  • The fit of my Metabones III adapter was also tight, but evidently not quite as tight as yours that is to say, I didn't fear damage to the lens or lens mount. It felt to me as though it was just on the cusp of being "nice and tight" vs. "a little too tight."
  • You are correct in that the button on the adapter seems to be useless in practice.
  • You can set one of the function buttons (I set #3) to act as a DOF preview button.

After another day/night of shooting with the camera I must say that I'm still quite pleased with the rig. I'm still not quite at the point that I feel completely comfortable having it replace my 5DII, however I have used it on one (relatively low impact) client job with success.
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David Campbell

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Re: Sony A7r questions
« Reply #45 on: December 21, 2013, 12:15:34 AM »

Thanks for the tip about the setting custom functions. I skimmed through the manual/index looking for depth of field but did not find anything. It must be buried deep in a menu  >:(

Paul2660

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Re: Sony A7r questions
« Reply #46 on: December 21, 2013, 12:47:24 AM »

David,

Did you notice any issues with the shifts on when using the TSE24?  There is another post in the forum where some users are seeing what may be the effect of reflections.    Here a link to the post:

http://www.luminous-landscape.com/forum/index.php?topic=85249.0

Paul Caldwell
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David Campbell

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Re: Sony A7r questions
« Reply #47 on: December 22, 2013, 12:33:02 AM »

Paul,

I had not noticed any reflections and did see marc's post.
When i first received the adapter, I thought it was odd that it did not have felt.
Once I saw marc's post, I went ahead and did it as well. So i wont be able to test to see if reflections are a big problem.

Regards
David

Deep

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Re: Sony A7r questions
« Reply #48 on: December 26, 2013, 05:11:36 AM »

I returned my A7R because of two problems that are each show stoppers for me.

1. The file compression applied to the raw files is lossy. Artifacts are clearly visible at 100 percent view as sort of an egg shell stipple on surfaces that should be smooth. While this would be unlikely to show in a print up to native size (and actually might help smooth transitions while maintaining a sense of surface), heavily working a file in Lr and Ps will make it worse and visible in prints. Tonal banding is also likely in more extreme cases since these are essentially 8 bit files.

2. This second problem is likely less of an issue for those using the camera hand held, but the problem of vibrations impacting image quality when used on a tripod is real. This was reported by Lloyd Chambers, and examples can be seen on his site. It has to do with the single curtain shutter mechanism on the R model. The A7 apparently has both and does not experience the same problem.

The first problem can probably be eliminated by a firmware update that would allow saving uncompressed 14bit raw files. Whether that will be forthcoming remains to be seen. But the second problem obviously can not. As I said, I do not think the vibration problem will be significant for street shooters because of the typical use of shorter lenses and hand holding the camera.

I am really disappointed because I have a lot of legacy lenses that I can't use with my 800e that I would like to use, and the reduction in weight would have been very welcome. I also like Sony's aggressive rethinking of what a pro/prosumer camera can be these days. I had a Sony R1 years ago that I really enjoyed using and made many very good images with. That experience convinced me that I would welcome a professional level mirrorless camera. For me the A7R is soooo close, but not quite there. Maybe there will be an A9R before long? I am hopeful.

The obvious answer is to get the A7.  It overcomes these problems.  Easy!

As for those people worried about tethering.  I find that a little bizarre, seeing that this camera is absolutely designed to be highly mobile.  Nevertheless, Sony do make the A99 which would be more suitable for tethering.
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Don

mattbr

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Re: Sony A7r questions
« Reply #49 on: December 26, 2013, 06:05:17 AM »

The obvious answer is to get the A7.  It overcomes these problems.  Easy!

Neither the A7 nor the RX1 spit out full RAWs (which was point 1), nor does Sony seem to have a history of aggressive firmware updates, which makes me pessimistic about the prospects.

This said, I'd be sincerely curious to see if the compression makes any difference in real-life scenarios.

And, yeah, the non-R does probably solve some of the vibration issues - electronic first shutter + lower resolution will do that for you, but the underlying problem (which I'm guessing is somewhere in the hardware design) isn't solved. Hopefully, it's something that can be helped with a few cents' worth of absorbent foam somewhere on the assembly line...
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allegretto

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Re: Sony A7r questions
« Reply #50 on: December 26, 2013, 08:21:51 AM »

Has anyone documented the problem when using lenses that do NOT require some form of "adapter"?
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Deep

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Re: Sony A7r questions
« Reply #51 on: December 26, 2013, 02:39:30 PM »

Neither the A7 nor the RX1 spit out full RAWs (which was point 1), nor does Sony seem to have a history of aggressive firmware updates, which makes me pessimistic about the prospects.

This said, I'd be sincerely curious to see if the compression makes any difference in real-life scenarios.

And, yeah, the non-R does probably solve some of the vibration issues - electronic first shutter + lower resolution will do that for you, but the underlying problem (which I'm guessing is somewhere in the hardware design) isn't solved. Hopefully, it's something that can be helped with a few cents' worth of absorbent foam somewhere on the assembly line...
With all due respect, any compression with the A7 is totally negligible and invisible in the few RAW files I have here (test photos designed to provoke the sensor).  Ditto shutter vibration (which feels vastly different between the two models).  If these issues are such a major concern to you, it seems that you really need a much heavier camera/tripod combination, maybe even a bigger format camera.  I understand the search for perfection, so I'm not being critical, just realistic.
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Don

mattbr

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Re: Sony A7r questions
« Reply #52 on: December 29, 2013, 04:18:05 AM »

With all due respect, any compression with the A7 is totally negligible and invisible in the few RAW files I have here (test photos designed to provoke the sensor).  Ditto shutter vibration (which feels vastly different between the two models).  If these issues are such a major concern to you, it seems that you really need a much heavier camera/tripod combination, maybe even a bigger format camera.  I understand the search for perfection, so I'm not being critical, just realistic.

FWIW, my comment about damping was based on the non-R. Extremely cursory examination makes me feel like the much talked-about volume level (a.k.a "OMG it isn't as silent as the leaf shutter on the RX1 or an M4" phenomenon) might have been somewhat alleviated with better damping and / or lower tolerances in the outer body assembly. I don't know if this is related to the sharpness problem some R owners are reporting, however, I'm pretty damn certain it wouldn't hurt.

Glad to hear the compression is a free lunch... I hadn't been able to find anything that gave an answer, one way or the other, which obviously made me curious. Because the camera also seems very prone to underexposure, at least with the lenses I've played with, I naturally can't help but wonder if compression and metering behaviour are linked - i.e, intentionally underexposing to compensate for something that would appear when exposing to the right.

Anecdotally, I've shot something like 10k files through my RX1, which seems to have the same sensor, often in very difficult light, and I'm extremely happy with the IQ it's spitting out... but hey, can't have too much of a good thing...
« Last Edit: December 29, 2013, 05:29:59 AM by mattbr »
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eronald

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Re: Sony A7r questions
« Reply #53 on: December 29, 2013, 01:25:13 PM »

Bernard

Exceptionally good picture, what tech details?

Edmund

Too bad, I use the 180mm f2.8 APO a lot on the D800 for distant pano stitches since those Leica R APO lenses are optimized for that very application. It looks like Sony didn't quite fully validate all the usage patterns here.



Cheers,
Bernard

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ErikKaffehr

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Re: Sony A7r questions
« Reply #54 on: December 29, 2013, 07:33:25 PM »

Hi,

I would suggest aliasing artifacts? I have not seen the "stipple effect", but a lot of Aliasing on A7r test images.

Diglloyd referred to an article describing the Sony file compression. They use some block size, save min and maximum value and use seven bits to code the difference for each pixel. It could cause quantization error in very steep gradients, I guess, but would be fairly good. They have something similar to gamma curve. Sampling tight at low data numbers and more sparsely for high data numbers where photon statistics dominate anyway.

Best regards
Erik

Hi Mark,

Thanks for your feedback. I'm a bit surprised by the 'egg shell stipple' effect you mention. I'd have expected an overly smooth effect, especially in the highlights, not structure. Tonal banding would indeed be the anticipated result when pushing the tonemapping a bit further than 'usual'.

It would be appreciated if you could post a crop that shows the effect.

Cheers,
Bart
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