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The Sony A7 thread [Merged]


dmclalla

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I've done an analysis of the corner chroma errors and corner luminance errors with these lenses mounted on an a7R:

 

  • Leica Super-Elmar 18mm f/3.8 ASPH
  • Leica Elmar 24mm f/3.8 ASPH
  • Leica Elmarit 24mm f/2.8 ASPH
  • Leica Elmarit 28 mm f/2.8 ASPH
  • Zeiss Biogon 35mm f/2
  • Leica Summilux ASPH 50mm f/1.4
  • Coastal Optical 60mm f/4 APO

Sony a7R testing, part 12 | The Last Word

 

Here's what the chroma errors look like vs f-stop:

 

 

chroma%20corner%20error.PNG

 

I suggest using this chart to figure out which lenses to try.on the a7R. Why not just use CornerFix? The correcting image depends on lens and f-stop, (and, with third-party (Leica) lenses, the metadata won't help you) and I find the amount of in-field record keeping necessary to use it onerous. I prefer to find lenses that don't need fixing.

 

Comments, suggestions for further testing are welcome.

 

Jim

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Do you mean this link?

Electronic Front Curtain Shutters

 

Thank you, Jan. Not exactly but also in this article a similar quote can be found:

"When you shoot at high shutter speeds with a large diameter lens attached, the ghosting of a blurred area may occur, depending on the subject or shooting conditions. In such cases, set this item to [Off]."

 

Seems to be a bad translation (should be large aperture instead of large diameter). Also the rest is not really clear, but someone said, this recommendation can also be found in some of the docs fpr the A7/A7R.

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Thanks Rick for your experience to date!

Aeturnum, excellent take:)

 

I have now had the A7r for just over 2 weeks, and I could only describe it as a love/hate relationship.

 

I have a number of lenses that work amazingly well, the 50 Cron Rigid DR, 50 Nocti f/1.0, 24 Lux Asph and the 75 Lux, and of course the FE 35/2.8 which is great to have. I have just tested the 50 Lux Asph, and although the results with the A7r would be fine on their own, and M240 is clearly better. The 35 Lux Asph it yet to be tested, but I already have the FE 35/.28, so I am in no rush.

 

I am a 50mm FL shooter, and mainly portraits, so in essence the camera should work great. The IQ from the above lenses are amazing, almost MF in quality. In fact better than from the M240.

 

Some of the ergonomics are the issue that are frustrating, and I do hope some will be addressed by firmware updates.

 

(1) The MF at the moment requires a two step function to accurately focus. This is important for portraits, as you wish to nail a near eye. With the M240, it is purely a movement of the focusing ring. I realize unless you opt for special adapter, such as Phigment this maybe resolved. Unfortunately they are not available.

 

(2) The sensitivity of the magnified focus mode is easily reset, just by movement of the camera, without pressing the shutter. I do have try the method suggested above and see if this does improve.

 

(3) The playback for reviewing is cumbersome. This is a three step process, so as to view files making the important parts of the image are in focus. Play, C2 and then the scroll button, which is very slow to reduce the magnification

.

(4) Another major issue is the EVF, in bright ambient light. I have tried setting the EVF to manual maximum brightness, and turned off the camera settings, and still I cannot view the scene when I have the lens set at f/2.8 or more. I have tried this with another A7r, and it has the same issue. For landscapes and seascapes, the exposure tends to the left, as to preserve the highlights in the clouds, and becomes almost impossible to see in the EVF. The LV display can be set for bright sunlight, this seems fine. In low lighting, inside or shade the EVF is great. I find the Oly VF2 on the M240 to work well in bright ambient light, even though it has a slightly lower resolution. The other problem, I am finding is the delay, and finding quite often for portraits, I have captured people with eyes closed, or the expression that I have just missed!

 

I want to love this A7r, and the IQ is amazing, but for now I will only use it with a few select lenses that I know that work. The forums, are now filled with testing that sometimes leaves more questions than answers.

 

Coming from a M240, and having a range of M lenses, the M240 is my choice for now. Though coming from a M9, the choice is not simple. There many functions on the A7/A7r, that the M9 does not have which makes the A7/A7r very attractive. If you have a large number of M lenses, the M240 may end up the cheaper option, as you can fully utilize all your lenses to their max.

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Thanks Rick for your experience to date!

Aeturnum, excellent take:)

 

(4) Another major issue is the EVF, in bright ambient light. I have tried setting the EVF to manual maximum brightness, and turned off the camera settings, and still I cannot view the scene when I have the lens set at f/2.8 or more. I have tried this with another A7r, and it has the same issue. For landscapes and seascapes, the exposure tends to the left, as to preserve the highlights in the clouds, and becomes almost impossible to see in the EVF. The LV display can be set for bright sunlight, this seems fine. In low lighting, inside or shade the EVF is great. I find the Oly VF2 on the M240 to work well in bright ambient light, even though it has a slightly lower resolution. The other problem, I am finding is the delay, and finding quite often for portraits, I have captured people with eyes closed, or the expression that I have just missed!

 

Have you tried temporarily turning the exposure compensation wheel to underexpose by a stop or two, then focus, and set the wheel back to the correct exposure? I encountered the problem with using Zebra and pointing at lights with f/1.2.

 

Provided you really only use the RAW files, you could set contrast to -3 and see whether that helps.

 

Obviously the camera needs some work by Sony.

But apparently we need to let them know first! :D

 

Good luck!

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Have you tried temporarily turning the exposure compensation wheel to underexpose by a stop or two, then focus, and set the wheel back to the correct exposure? I encountered the problem with using Zebra and pointing at lights with f/1.2.

 

Provided you really only use the RAW files, you could set contrast to -3 and see whether that helps.

 

Obviously the camera needs some work by Sony.

But apparently we need to let them know first! :D

 

Good luck!

 

Thank you:) I use RAW and Jpegs, I know several others that shoot beach scenes have had the same problem. I have not tried the compensation wheel, as I sometimes shoot a sequence of shots trying to captures the waves at the right moment, would negate this option. I will the try the contrast setting at -3, and manual brightness of +2. It would seem there is a limitation to the maximum brightness, not being set correctly by the external light sensor.

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Especially when in Live View mode, as the 5D2 has EFCS ;)

 

Hehe, sure! Actually I meant normal hand held to the face optical viewfinder stlyie. I believe it's something to do with "ergonomics", a dark mystical craft where objects are designed to fit to the human form. This is different to the craft of fitting an object around two spools of film with a flat plate in between..... ;):)

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Hehe, sure! Actually I meant normal hand held to the face optical viewfinder stlyie. I believe it's something to do with "ergonomics", a dark mystical craft where objects are designed to fit to the human form. This is different to the craft of fitting an object around two spools of film with a flat plate in between..... ;):)

 

 

Interesting.

I try to shoot on a tripod or with something like 1/(3*FL) my D800E, A7R, and NEX-7.

That is for lenses with typical rangefinder focal lengths.

Image stabilization works well on my Nikkor 80-400 II lens.

Nikon calls that feature Vibration Reduction or VR.

This avoids my shaking hands ruining a picture.

 

For shooting hummingbirds I try to have an exposure time in the 1/1000 to 1/2000 s range.

Similar parameters I used with my OM-D EM-5 and 5-axis IBIS.

 

But with the EM-5 and WATE I managed to get a pretty sharp handheld night shot at ⅓ s.

The OM-D EM-1's In-Body-Image-Stabilization IBIS is even better, truly amazing.

With it I can shoot my Leica rangefinder lenses approaching 1s handheld for static subjects.

I find that incredible.

 

Birds In Flight BIF I shoot handheld with 600 mm 135 film equivalent FL. No problem.

What's so amazing about IBIS is as soon as I half press the shutter the shaking in the viewfinder stops.

That's a great feature for manual focusing of rangefinder lenses in particular.

 

Luckily Olympus and Sony are already collaborating to integrate IBIS into the Sony cameras.

Having IBIS in a FF A7R like camera would be fantastic even if it has to be somewhat bigger.

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Camera shake and shutter speeds.....

 

 

Experience with my D800E was, that I had to choose 1 / (focal length x 3) as shutter time when hand held to get a sufficient percentage of pixelsharp photos - even with locked up mirror. So the expectation to get pixel sharp images on A7R at the classic rule of thumb (1/focal length) is not realistic anymore with such a sensor - independent of EFCS.

 

If there is a negative influence by the FCS, I think, it also depends on many other factors like the shutter time itself (resonance frequency of the overall system of lens and body etc.). As far as I remember, there was a particular issue e.g. with one of the early Oly PENs with particular lenses and particular shutter times (e.g. around 1/125s or so) that was solved later by a firmware update avoiding these problematic times.

 

To be clear: I do not want to whitewash, if there is an issue but from my experience this has to be investigated in more detail and can not be generalized. We saw that already in the discussion about WA RF lenses, where this article proved wrong the generalizations like "skip the A7/A7R if you want to shoot M-lenses below 35mm".

 

........I have to say I find the problem inexplicable ........ on an M with my 50/2.8 I can take consistently in-focus images at 1/30 ...... and often much less......

 

With the A7r and the same lens I need 1/90 or faster to get ANY handheld images that are 100% sharp.

 

The 'extra pixels' explanation is patently suspect as the difference is 24 versus 36 mp .... which only equates to a lateral/vertical increase of x1.2..... which cannot account for such a large discrepancy......

 

Possibly the explanation is actually the smallness and lightness of the camera ....... it is far more difficult to shake /vibrate (and be influenced by the shutter) a camera if you are relatively heavy like the M. The frequency of vibration will also probably be less. Below a certain weight (and inherent inertia) and size, holding steady may actually get progressively more of a problem. Too heavy and fatigue and wobbling start to be an issue.

 

Camera ergonomics seems to be neglected issue in favour of electronic gizmos and fixes. :rolleyes:

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I thought I would post some photos as a followup. Here is a set shot in relatively low light, mostly with the Nocti 50mm, though with some from the Voigtlander Nokton 35mm and some with a Jupiter-9 85mm (USSR LTM len). If the non-leica lenses are not appropriate, please feel free to remove the post.

 

Krista's Birthday Party

 

The set isn't any sort of formal test of the camera, but might give everyone here an idea of what it's capable of doing. There are plenty of poor photos in the set, and photos which have sub-optimal settings (I tried iso 256000 and regretted it, but I posted one photo at that sensitivity). I often missed critical focus to the detriment of the photo, but the results were often pretty good anyway.

 

As you can see, I had a number of problems with color at high-ISO. While not unpleasant, the color profile is definitely going to take some time to adjust to. It's possible that the light is more to blame than the camera. Hard to say with only one camera. The noise performance is stellar - this photo is at iso 128,000! It's shockingly good if carefully exposed.

 

Here are two more informal portraits shot on the A7 w/ the 50mm Nocti: one and two.

I don't remember the f-stop, maybe f/2? I don't really like the 'look' of the camera at base ISO, but that's what film is for. :)

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on an M with my 50/2.8 I can take consistently in-focus images at 1/30 ...... and often much less......

 

Sure, you mean "in-focus"? Anyhow - consistently sharp at 1/30s with a 50mm lens is simply no realistic expectation neither with a 24 MP nor a 36 MP sensor.

 

The noise performance is stellar - this photo is at iso 128,000! It's shockingly good if carefully exposed.

 

Nice pics, but EXIF says 12,800.

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