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Electronic shutter on K1

pschlute
Posted 02/01/2017 - 19:27 Link
Still getting to know all the features on the K1, I was experimenting with a 2x teleconverter and DA*300mm lens. The lens was firmly anchored on a Gitzo basalt tripod with centre ball head, and using a remote (SR off) I took some shots of a building about 100 feet away. I used live view to focus at 100% magnification.

I was getting what I assume to be shutter induced shake. Trying the mirror lock-up made no difference. I then tried the electronic shutter feature in live view and it nailed it. This was repeatable time and time again.

Have a look at the two photos (100% crops) to see the difference. is this what is to be expected as the difference between shutter and electronic shutter.... or is my tripod not up to scratch ?

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McGregNi
Posted 02/01/2017 - 19:39 - Helpful Comment Link
There's something going wrong with that first one ..... No reason not to expect the result of the 2nd with a normal mirror up technique, surely? I've never seen that sort of blurriness resulting from any sort of shake effect, not on a tripod at least. I wonder what else could be happening with the first approach, something else causing movement?

Electronic shutter is a very new concept here, in a DSLR context ..... Could you, or anyone, explain what it is and how to operate it on the K1 .... That would certainly aid understanding and help here I think.

What exposure mode were you using? Are you certain that the exposure settings were identical between the two? Especially the exposure time ....
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Pentax K7 with BG-4 Grip / Samyang 14mm f2.8 ED AS IF UMC / DA18-55mm f3.5-5.6 AL WR / SMC A28mm f2.8 / D FA 28-105mm / SMC F35-70 f3.5-4.5 / SMC A50mm f1.7 / Tamron AF70-300mm f4-5.6 Di LD macro / SMC M75-150mm f4.0 / Tamron Adaptall (CT-135) 135mm f2.8 / Asahi Takumar-A 2X tele-converter / Pentax AF-540FGZ (I & II) Flashes / Cactus RF60/X Flashes & V6/V6II Transceiver
Edited by McGregNi: 02/01/2017 - 19:41
pschlute
Posted 02/01/2017 - 20:02 Link
Hi

Both were 1/30 s using manual exposure. Tripod is rated for 5.4kg and head is rated for 4kg. SR was off, and I was using a remote to trigger.

Electronic shutter works (i think )in LV by electrically resetting the (already exposed) sensor so the image starts to be recorded. The trailing mechanical shutter then "closes" the exposure.

I will try and do some more extensive tests tomoorow at varying shutter speeds.
Mag07
Posted 02/01/2017 - 20:24 - Helpful Comment Link
The tripod may or may not be fine but I somehow doubt a ballhead rated for 4kg can keep K1+300mm plus teleconverter without slipping, ever so slightly - which may just be enough. Easy to test though; set your gear on the table and see if it behaves the same way at the same shutter speed? Just a thought.
'Photography...it remembers little things, long after you have forgotten....' (Aaron Siskind)
pschlute
Posted 02/01/2017 - 21:00 Link
Good idea. Will give that a try tomorrow. I had to come in from the garden not because I was losing light but because I was losing sensation in my fingers. It suddenly got very cold again
RobL
Posted 02/01/2017 - 22:16 Link
Did you get the autofocus indicator in the viewfinder? The other day with a temperature around zero the focus squares in the K-1 came on but no red flash, and pictures were not sharp. I thought I was too close so moved back, tried three different lenses but got the same result. Back home everything worked fine so as the battery indicator was getting low I wondered if that was the factor given the low temperature.
Edited by RobL: 02/01/2017 - 22:18
johnriley
Posted 02/01/2017 - 23:06 Link
The red flash does not indicate correct focus, just the point being focused on. The green hexagon at the bottom of the frame should be steady, not flashing, which indicates focus has been achieved.
Best regards, John
pschlute
Posted 02/01/2017 - 23:13 Link
I was manually focussing using live view 100% zoom. The difference between the shots was using mechanical or electronic shutter
RobL
Posted 03/01/2017 - 08:19 Link
johnriley wrote:
The red flash does not indicate correct focus, just the point being focused on. The green hexagon at the bottom of the frame should be steady, not flashing, which indicates focus has been achieved.

I should have said the red flash from the focus frame which coincides with the green hexagon and bleep. As I no longer have the eyes of a twenty year-old I use the focus assist in manual mode as well.
McGregNi
Posted 03/01/2017 - 08:43 Link
Its important to remove any other variables from the equation ..... ie focusing, exposure settings, the support etc. This seems to have all been confirmed by Peter, and he is saying that the only technical differences between the shots is the use of the electronic shutter feature. The question is therefore, why would there be more movement during a normal exposure cycle than there is during the electronic shutter cycle ?

Am I right to understand that the physical shutter is open for some period prior to an exposure being taken with the electronic shutter feature?

The only other thing to ask is what was the length of time between raising the mirror and releasing the shutter when using a normal 'mirror up' technique? I usually pause for at least 3 secs or so .....
My Guides to the Pentax Digital Camera Flash Lighting System : Download here from the PentaxForums Homepage Article .... link
Pentax K7 with BG-4 Grip / Samyang 14mm f2.8 ED AS IF UMC / DA18-55mm f3.5-5.6 AL WR / SMC A28mm f2.8 / D FA 28-105mm / SMC F35-70 f3.5-4.5 / SMC A50mm f1.7 / Tamron AF70-300mm f4-5.6 Di LD macro / SMC M75-150mm f4.0 / Tamron Adaptall (CT-135) 135mm f2.8 / Asahi Takumar-A 2X tele-converter / Pentax AF-540FGZ (I & II) Flashes / Cactus RF60/X Flashes & V6/V6II Transceiver
pschlute
Posted 03/01/2017 - 09:19 Link
McGregNi wrote:


Am I right to understand that the physical shutter is open for some period prior to an exposure being taken with the electronic shutter feature?

The only other thing to ask is what was the length of time between raising the mirror and releasing the shutter when using a normal 'mirror up' technique? I usually pause for at least 3 secs or so .....

Nigel

The electronic shutter can only be used in live view, so yes the mirror and shutter is open while I focus. As I understand it only the trailing shutter operates to end the exposure.... any vibration from this is too late to affect the image.

When using mirror lock up I was waiting anything from 2 to 5 seconds before triggering the shutter with the same results.

I am thinking it is my tripod/head. Although rated at 5kg and 4 kg respectively, I think they are not up the job when using almost 2.5 kg of kit. More experimentation to follow, but a bit of testing in the kitchen last night did seem to show that the shutter speeds in the 1/30 to 1/90 range produced the worst results, with graduated improvement as speeds got slower or faster than these
Edited by pschlute: 03/01/2017 - 09:22
Algernon
Posted 03/01/2017 - 11:18 Link
It's very difficult (almost impossible) to hold 300mm + TC steady even on a tripod.

I normally use SR ON with big lenses even with a tripod. You have to use the release on the camera by hand. SR switches off with IR enabled.

This is one area where in lens SR is better because it can be used easily on a tripod.

Try this test with a 50mm lens to see how it works out.
--
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
McGregNi
Posted 03/01/2017 - 12:02 Link
OK, sure, but none of this seems to be explaining why the shake does not occur during an electronic shutter exposure. The camera is on the same tripod with the same lens and TC for both the electronic and normal exposures .....
My Guides to the Pentax Digital Camera Flash Lighting System : Download here from the PentaxForums Homepage Article .... link
Pentax K7 with BG-4 Grip / Samyang 14mm f2.8 ED AS IF UMC / DA18-55mm f3.5-5.6 AL WR / SMC A28mm f2.8 / D FA 28-105mm / SMC F35-70 f3.5-4.5 / SMC A50mm f1.7 / Tamron AF70-300mm f4-5.6 Di LD macro / SMC M75-150mm f4.0 / Tamron Adaptall (CT-135) 135mm f2.8 / Asahi Takumar-A 2X tele-converter / Pentax AF-540FGZ (I & II) Flashes / Cactus RF60/X Flashes & V6/V6II Transceiver
Algernon
Posted 03/01/2017 - 12:18 Link
Peter answered this in the first post...

" I was getting what I assume to be shutter induced shake. Trying the mirror lock-up made no difference. I then tried the electronic shutter feature in live view and it nailed it. This was repeatable time and time again."

No further explanation necessary.

--
Half Man... Half Pentax ... Half Cucumber

Pentax K-1 + K-5 and some other stuff

Algi
McGregNi
Posted 03/01/2017 - 14:42 Link
I thought his first post was a question, not an explanation ... Are we now jumping straight to the conclusion that there is shutter induced shake when not using electronic shutter? I hadn't thought we were quite there yet.
My Guides to the Pentax Digital Camera Flash Lighting System : Download here from the PentaxForums Homepage Article .... link
Pentax K7 with BG-4 Grip / Samyang 14mm f2.8 ED AS IF UMC / DA18-55mm f3.5-5.6 AL WR / SMC A28mm f2.8 / D FA 28-105mm / SMC F35-70 f3.5-4.5 / SMC A50mm f1.7 / Tamron AF70-300mm f4-5.6 Di LD macro / SMC M75-150mm f4.0 / Tamron Adaptall (CT-135) 135mm f2.8 / Asahi Takumar-A 2X tele-converter / Pentax AF-540FGZ (I & II) Flashes / Cactus RF60/X Flashes & V6/V6II Transceiver
Edited by McGregNi: 03/01/2017 - 14:45

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