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You'd think, and there are images which clearly show what you suggest - see post #36 in this thread. However, when I look at point sources with a nonresonant mounting system I see a circle of blur. Not sure if it is actually Gaussian, just trying to get across the falloff around a center.Why would shutter vibration lead to Gaussian blur? I would expect the blur to be parallel to the shutter motion, not nicely anisotropic Gaussian.
--Matt
Oddly enough I have Gitzo series 1 tripods and series 3 tripods. Arca Z1 head, and light weight Acra heads. The heavier tripod setup did not result in lesser blur manifestations - or if less very difficult to see with results from a 90mm lens. Longer lenses may produce different results.Just to clarify, the Gaussian blur (shutter vibration) that the A7r exhibits is quite subtle. There is a gross blur as well, that happens if you use a rigid, light and resonant support system but that is not really the camera's fault. Just don't mount that way.
Victor, could you post an image of your tripod?Test camera vibration files are off to Sony. Camera in vertical position, 90mm Leica, 10s delay. Big difference between the worst and best files. At least they are looking into this.
Victor
You'd think, and there are images which clearly show what you suggest - see post #36 in this thread. However, when I look at point sources with a nonresonant mounting system I see a circle of blur. Not sure if it is actually Gaussian, just trying to get across the falloff around a center.
I think the entire CCD package is resonating in relation to the shell. The plane of resonance appears to decouple - at least partly - from its source. Or I could be wrong. I have no testing equipment here. It's great that Sony is now looking into to it (see above posts).
:toocool:Mr. Lovisolo, You and I need a subscription. That is the problem. :ROTFL:
Sergio, my mistake lay in not posting images earlier. Here are two crops. They are a peeper's delight at about 4:1 so the issue becomes fairly obvious. One is at 1/60 and the other at 0.5. I will leave it to you to judge which is which. I have some others using flash in which the difference is clearer.Victor, could you post an image of your tripod?
With this setup
_DSC3260 by sergio lovisolo, on Flickr
I can't get motion blur at any shutter speed, no trace even with finest details
of test target.(elmarit m 90)
Casual subject at 1/25
_DSC0435 by sergio lovisolo, on Flickr
test target at 1/30 and 100% crop
_DSC0436 by sergio lovisolo, on Flickr
Thanks.
Thanks for posting these, cunim! It seems to me that this level of blur may very well negate the advantage of 36MP over 24MP.However, it is not necessary to get technical to decide whether this level of blur matters to you.
Sergio, my mistake lay in not posting images earlier. Here are two crops. They are a peeper's delight at about 4:1 so the issue becomes fairly obvious. One is at 1/60 and the other at 0.5. I will leave it to you to judge which is which. I have some others using flash in which the difference is clearer.
The point is this camera can deliver wonderful resolution but only under the right conditions. We are deluding ourselves if we think we can get around that.
Conditions: Foba Asaba studio stand with Sinar head, AS clamp on stand and AS plate tight on camera. A7r, iso 200, Apo Summicron M 90 asph. No sharpening applied.
As you can see, you need to look carefully. I would be very interested to see your resolution chart snapped at 1/60 vs 0.5, with a 100% crop.
The best way to lay all this to rest is to derive point-spread functions. I am sure someone here could do that if they wanted to. However, it is not necessary to get technical to decide whether this level of blur matters to you.
Hi RonThanks for posting these, cunim! It seems to me that this level of blur may very well negate the advantage of 36MP over 24MP.
Edit: the same can probably be said about lens quality (i.e. the blurred image may as well have been taken with a far less expensive lens)
One of the tripods I have is a Sachtler DA-75 (aluminum) with a Manfrotto fluid head. There is a heavier fluid head as well but that weighs more than this combo. There are carbon fiber versions of the DL-75 which are a lot lighter.Holy cow, Sergio - how much does all of that stuff weigh?:shocked: The next step would be to weld that little puppy to an I-Beam. My series 3 and Arca Z1 setup is not enough to calm down the vibration from this little camera. If I have to get beyond that then something surely is amiss.
Victor
Woops, forgot to specify that. Shots at f3.5 or f4, can't remember. Set a Profoto D4 and soft box to get the 1/60 to work at iso 200. Then just turned down the light for the longer exposures.How do you manage the +/- 3 stops between the two pictures ?
Jono, I agree and I don't. Let's say for now, I'm opting to disagree. I *want* the A7R to deliver as much as my lenses (or its sensor) are capable of, and I'm willing to walk the extra mile to get there. This was the primary reason why I chose this model over the A7. But it may turn out that this goal is not achievable very often in reality. Further use will deliver the answer to this question. For now, I remain positive. I think I can work around the faster than 1/3f or slower than 2s rule when it matters...Hi Ron
This is the way I'm thinking as well. Together with the reduced shutter lag there seems to be quite a lot going for the A7.