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11-07-2016, 05:45 AM   #1
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Shutter shock, shutter vibration, mirror shock, mirror damping; there has been talk about this. I know physics and there is nothing that beats a good experiment to settle an issue. I took pictures of the sunrise through fog this morning. I was using the K1 and the 15-30mm F2.8 lens. I took shots at both 30mm and 15mm. The camera was supported on the ledge of the window which is on the 17th floor and the ledge is made of granite attached to the cement wall of the building with adhesive and more solid than a tripod. This allowed the camera and lens to both be supported. I took identical shots with both the viewfinder and using live view and the electronic shutter. The resulting pictures when viewed in OpticsPro 11 by DXO showed significant differences in the clarity at 100% that was very easy to see, with the better pictures being the electronic shutter. The only significant variable seems to be the vibration created by the camera mirror. I tried the same thing using a tripod. The differences still existed, but were not as acute or significant as those with the camera resting on the granite. What have the rest of you found?

11-07-2016, 06:59 AM   #2
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A (good) tripod should definitely be more stable than resting on a solid surface, since the mirror will creat torsional and gyroscopic effects that won't be damped by resting loosely as compared to being screwed down.
11-07-2016, 07:33 AM   #3
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QuoteOriginally posted by reverendray Quote
I know physics and there is nothing that beats a good experiment to settle an issue.
I'm always interested in these types of experiments and trials. Thanks for summarizing the results. May I suggest that adding some essential information would be useful:

- What shutter speeds did you try?
- Did you trip the shutter with a remote control or with the on-camera shutter button?
- Was there any significant difference in results at the two aperture settings?
- What effect, if any, did the fog have on the "clarity" of the images?
- Did the mechanical shutter introduce any effects when using 'viewfinder' mode?

- Craig

Last edited by c.a.m; 11-07-2016 at 07:48 AM.
11-07-2016, 02:02 PM   #4
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Shutter speeds were at 1/60 sec
yes I used the remote control to trip the shutter
There was little difference between 30mm and 15mm
I used for "clarity" bricks in the wall of the hospital across the street at 200%
When ramped up later, after posting, above 1/200 there is not effect that I can see.

I did not use a tripod knowing that it would have a damping effect.
Torsion effects of course occur when the mirror swings but these should not "resonate" within the unit; such resonance being one possible issue that could not really be measured with a simple home setup. I am going to guess that higher speeds are quick enough to make the "shake" no longer a factor.

11-07-2016, 06:42 PM   #5
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SR turned off?
11-08-2016, 04:23 AM   #6
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SR Off?

No it was not turned off.
11-08-2016, 05:14 AM   #7
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QuoteOriginally posted by reverendray Quote
No it was not turned off.
Try it again with SR off. It may be trying to correct for things not there
11-09-2016, 02:49 AM   #8
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Very good point.....thanks will try it

11-15-2016, 02:32 PM   #9
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Ok this is what I have found. Excellent performance with the 15-30 on K1 placed on tripod:
Live View with electronic shutter
SR on
No significant differences in: Shutter Speed, manual or auto focus, remote release or shutter release.

Using eye piece view I found that any degradation of picture sharpness from possible mirror slap disappeared:
remote release with mirror up 3sec before picture
1/150 sec exposure time.

At this point I had what I needed to know and did not explore further. By excellent I mean that the center and edge of picture at 100% were acceptable for printing.
11-16-2016, 05:40 AM   #10
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Short Addendum: The suggestion to use the live view electronic shutter was a good one. It works fine in most cases except where a quick picture has to be taken of events like kids, dogs, candid street shots and etc but you can use a higher shutter speed usually in those cases. Generally this seems to be a reasonable user fix.
11-16-2016, 06:03 AM   #11
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QuoteOriginally posted by victormeldrew Quote
the mirror will creat torsional and gyroscopic effects that won't be damped by resting loosely as compared to being screwed down.
...the bottom line here is that everything does better with a good screwing.
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