My test of shutter shock on K-3 III

[MarBa]

I printed a B&W text on a laser printer (1200 dpi, smallest is font 5, Times New Roman), placed the paper on a wall. Then set up my K-3 III with DFA 100 macro right opposite on a sturdy tripod. I manually focused using magnified view in LV as well as I could. I used a cable release to trigger the shutter from LV with a 2s timer (does mirror lock-up). I kept the overall exposure the same for each of the two exposure time / ISO / aperture series (one with f/5.6 one f/8). I turned the SR and horizon correction OFF as well as every possible in-camera image processing (NR, lens correction, clarity etc.). I always waited few seconds after changing the time/ISO to make sure the camera does not shake. Then I imported the DNGs into LR, used default profile, no sharpening. I only changed white balance for all images to the same value and lifted one of the two series by 1EV to have the same looking images. Times were from 1/640 to 1/10 (by one stop), should be in EXIF of the images posted below.

In addition, I did a more detailed series, going by 1/3 of a stop at f/8, and I compared turning the horizon correction on and off. That had no influence on sharpness (but I did see slight variation in rotation in the image series). Times were from 1/5 to 1/160. I also tried 0.4s at f/11.

I looked at all my images in detail in LR at 400% (also at exported JPGs) but I can't find any signs of shutter shock .. Either I don't really reach the ultimate sharpness .. or my camera does not have this problem .. or there are some settings that I had different than when DPreview did their test?

Any comments? Suggestions?

 

[iso rivolta]

The images look indeed very similar between them. I wonder if dpreview left ON something related to sensor movement. It also depends on the tripod and the type of release. Cable release or remote might be better than self-timer (pressing the camera button can induce slight defocus or vibration).

 

[KPM2]

Hello MarBa

Thank you for your test !

Maybe look what happens with the sharpness at this crops, when you switch the AA filter to on ?

best regards. KPM2

 

[MarBa]

Hello MarBa

Thank you for your test !

Maybe look what happens with the sharpness at this crops, when you switch the AA filter to on ?

best regards. KPM2

I don't have it set up anymore but I don't see how AA filter would explain what Dpreview saw. I would expect that they had AA off.

 

[MG Monochrome conversion]

Bravo!

 

[PeterPentax]

You took these images in LV.....was the Electronic shutter enabled ?

 

[iso rivolta]

You took these images in LV.....was the Electronic shutter enabled ?

There is no electronic shutter inside K-3 III with current firmware and I'm sure MarBa did not use pixel shift.

 

[PeterPentax]

You took these images in LV.....was the Electronic shutter enabled ?

There is no electronic shutter inside K-3 III with current firmware and I'm sure MarBa did not use pixel shift.

Thanks for the clarification. That actually surprises me that Pentax did not include ES

 

[ozdean]

No Shutter Shock or Mirror Slap there.

 

[James O'Neill]

Hello MarBa

Thank you for your test !

Maybe look what happens with the sharpness at this crops, when you switch the AA filter to on ?

best regards. KPM2

I don't have it set up anymore but I don't see how AA filter would explain what Dpreview saw. I would expect that they had AA off.

I may have created some confusion on another thread. ExifTool reports that AA is set to 1 for DP review's ISO 100 images. However it reports "1" for images where I know AA is off on my K1 so either 1 is no AA or the program is looking at the wrong field.

 

[madbrain]

Hello MarBa

Thank you for your test !

Maybe look what happens with the sharpness at this crops, when you switch the AA filter to on ?

best regards. KPM2

I don't have it set up anymore but I don't see how AA filter would explain what Dpreview saw. I would expect that they had AA off.

I may have created some confusion on another thread. ExifTool reports that AA is set to 1 for DP review's ISO 100 images. However it reports "1" for images where I know AA is off on my K1 so either 1 is no AA or the program is looking at the wrong field.

I would suggest checking with Pentax Digital Camera Utility 5.9.2 .

On my K-1 II, DCU shows the AA filter simulator in the "Shake Reduction" field.

With SR on but no AA filter, it says "On". With SR and AA filter simulator type 1, it says "On / Type 1".

With SR off and AA filter set to type 1, it says "Off / Type 1".

For the DP Review ISO 100 RAW file (IMGP4036.DNG), it shows "Off" under Shake Reduction, so no AA filter was used.

 

[Don Kiyoti]

"Either I don't really reach the ultimate sharpness .. or my camera does not have this problem"

I'm not sure I follow you here. Are you saying these photos could be sharper? Please clarify.

 

[Lakecat]

Yeah, DPR screwed it up again.

 

[MarBa]

You took these images in LV.....was the Electronic shutter enabled ?

There is no electronic shutter inside K-3 III with current firmware and I'm sure MarBa did not use pixel shift.

No pixel shift and AA was off just to be clear.

 

[MarBa]

You took these images in LV.....was the Electronic shutter enabled ?

 

[iso rivolta]

You took these images in LV.....was the Electronic shutter enabled ?

There is no electronic shutter in K-3 III. When you take an image from LV, it's like a normal exposure. Shutter closes first and mirror goes down to end LV .. then the mirror goes up for 2s because of the timer and then you get an exposure by moving shutter. ... Well at least that is what I think is happening. It's definitely quite an elaborate procedure.

The mirror shouldn't cycle in LV shooting. Since K-7 the flagship cameras used the separate mirror, shutter and aperture motors to keep the mirror up in live view. You can check this by looking in the OVF when you press the shutter, no light should be visible if the mirror stays up.

What you're hearing with LV is (1) the shutter closing (second curtain) and the aperture stopping down and then (2) the shutter opening and closing (the two curtains traveling) to take the picture and finally (3) the first curtain of the shutter opening once more (and possibly the aperture too, depending on settings and light level), to allow LV again. The self-timer is inserted between steps (1) and (2).

 

[John Cal]

Thanks for your test results. I have found no shutter shock issues at low shutter speeds with my K3 Mkiii. The image quality and focusing abilities are at a premium level. Its disappointing that DPR didn't try another body and lens combo's before potentially putting off prospective buyers from what will emerge as a high value photographers tool for years to come. Pentax can't get a fair go for all their hard work. Anyway it will come out in the wash. My K3iii is a keeper. Love it.

Keep calm and carry on.

 

[James O'Neill]

Hello MarBa

Thank you for your test !

Maybe look what happens with the sharpness at this crops, when you switch the AA filter to on ?

best regards. KPM2

I don't have it set up anymore but I don't see how AA filter would explain what Dpreview saw. I would expect that they had AA off.

I may have created some confusion on another thread. ExifTool reports that AA is set to 1 for DP review's ISO 100 images. However it reports "1" for images where I know AA is off on my K1 so either 1 is no AA or the program is looking at the wrong field.

I would suggest checking with Pentax Digital Camera Utility 5.9.2 .

On my K-1 II, DCU shows the AA filter simulator in the "Shake Reduction" field.

With SR on but no AA filter, it says "On". With SR and AA filter simulator type 1, it says "On / Type 1".

With SR off and AA filter set to type 1, it says "Off / Type 1".

For the DP Review ISO 100 RAW file (IMGP4036.DNG), it shows "Off" under Shake Reduction, so no AA filter was used.

I'm not 100% sure that last bit is correct, you may not want SR on but still want moiré avoidance

 

[jonby]

Thanks for these tests, MarBa. Could you share with us the details of the tripod/support setup for this test? It would be interesting to have this info at hand when/if DPR come back following their 'further investigations'.

For example, what kind of tripod/head, aluminium, carbon fibre, is it fully extended/minimum extension, was the centre column extended, what kind of surface is it resting on (carpet, concrete etc)?

I'm hoping DPR may share their setup, so we could compare (though they may not).

Because the issue is all about resonant vibration, all these things can play a part. It's even possible that an outwardly more 'stable' setup (super-heavyweight tripod etc) can produce worse effects than a looser, more lightweight setup, or at least the problematic shutter speeds can shift.

Having a quick look at your tests, I can't see any obvious shutter shock, which is encouraging - especially since you included a fairly long focal length, which you would expect to exacerbate things.

 

[PC-dot-Com]

With hundreds of owners using the K3 Mk III prior to DPR, with all of them questioning shutter shock ZERO times, and no one else able to duplicate DPR's "findings" including myself, I call a botched test.

A bit irresponsible to post those findings without first eliminating all possible causes (including user error) first.