[stevebrot]

If this is the case, you'd hope Pentax would have addressed this in the firmware, and disabled the SR system at those shutter speeds?

I will have to find the thread, but I don't believe the behavior was completely characterized or is universal. I will report back if I find it.


Steve

I did a fairly thorough look-back and found a lot of stuff for the K-1 in the last year, but only this report for the K-3...

K-3 shutter shake at and around 1/100s - PentaxForums.com

Edit: I just noted on the thread linked above that I commented regarding users who were certain of a relationship of SR to blur within a shutter speed range. Apparently my memory was better 9 months ago regarding such than it is now.

In the end, user harisf1 decided that it was a quirk with his hand-held technique. I did find a glancing reference using Google from a few years ago where someone was asking if the K-3II had the same shutter shock characteristics as the K-3, but the user did not elaborate as to what that might be.



Steve

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Last edited by stevebrot; 08-08-2017 at 06:15 PM.

[richandfleur]

Yeah I've never experienced the issue, but then I haven't been actively looking for it / testing either.


As above though, if there was an issue at a certain shutter speed, then I'd expect it to be addressed in firmware, rather than left to the user to remember to turn it off/on on the fly.
Having to do it manually would be a real paid, especially in the auto modes like AV, where the camera could decide at any time to pick that shutter speed, based on metering calcs at the time.

[awscreo]

With the K-1, right?


Steve

Yup, I posted few months ago with samples

[stevebrot]

My dfa 28-105 has shutter shock from 1/30 to 1/200, pretty broad range. I meant to call them, see if it's maybe fixable somehow under warranty, so far I haven't seen anyone on pf with such issues with this combo.

The shutter can cause visible vibrations between about 1/90s and 1/180s, and this looks like it might be an example of that. There was a long thread on this topic earlier this year.

I've ran into mirror shock myself with my 28-105, since then I only use LV mode with ES option on to eliminate any possibility of this effect. Kind of a pain when I'm hand holding some of my lenses, but I guess nothing is perfect.

If this is the case, you'd hope Pentax would have addressed this in the firmware, and disabled the SR system at those shutter speeds?

They did, they added the electronic shutter option. SR is not to blame, it's the shutter. But yes, SR gets disabled when ES is on in the K-1.

There was another lengthy thread on the topic, which ultimately resulted in identification of the problem (note that this was before they added the ES solution):

Help needed figuring out D FA 28-105 - PentaxForums.com

I am a bit confused. All of these comments are about the K-1. This thread is about apparent artifact on the K-3. Was there a branch in the road that I missed?

Just my two cents, I believe that SR is a red herring here. The blur on the bird looks to be subject motion. In regards to the general softness...At first I thought something optical, but at present, I don't think it is possible to rule out camera motion or missed focus. I also wonder about moisture condensation on the front element and/or atmospheric refraction.

If there are problems with SR with the lenses in question at those shutter speeds, it should be easy enough for the OP to test for under conditions more controlled than over water and snow at 0-2 C. I have done plenty of hand-held work with my K-3 in the range of 28-105mm at moderate shutter speeds using SR and have not seen anything unusual. I don't have any glass over 200mm and can't test on the long side.


Steve

[Adam]

I am a bit confused. All of these comments are about the K-1. This thread is about apparent artifact on the K-3. Was there a branch in the road that I missed?

Just my two cents, I believe that SR is a red herring here. The blur on the bird looks to be subject motion. In regards to the general softness...At first I thought something optical, but at present, I don't think it is possible to rule out camera motion or missed focus. I also wonder about moisture condensation on the front element and/or atmospheric refraction.

If there are problems with SR with the lenses in question at those shutter speeds, it should be easy enough for the OP to test for under conditions more controlled than over water and snow at 0-2 C. I have done plenty of hand-held work with my K-3 in the range of 28-105mm at moderate shutter speeds using SR and have not seen anything unusual. I don't have any glass over 200mm and can't test on the long side.


Steve

I think mention of the lens led to the assumption that the K-1 was the camera in question. Disregard my comments for the K-3, and you're right it could be the SR in that case.

[awscreo]

Yup, I guess I didn't notice it was about k-3)