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01-11-2018, 06:00 PM   #1
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pixel shift mode k-1

Hello,
I would like to share some observation. I wanted to check the difference between the pixel shift and the single photo mode with a new lens. Pointed the camera at the monitor and made several photos.
I paste one of them and a crop here because I have no idea what it is.



Few observations.
The violet bar appears at different shutter speeds and different apertures, regardless of the SD card and SD slot.
It appears when I move the focus slightly backward or forward, just enough to make the moire disappear.
The bar disappears hovewer when focus is moved significantly and the picture is vague.
The bar disappears when another website is opened
and is coming back when the Google browser is opened. So I open different websites and Google alternately a dozen times and every time when I take a picture of Google browser, the violet bar appears and in the pictures of other sites the bar disappears. It disappears in pictures of desktop, photos, programs also.
Of course it happens by accident. So is it a fault ?

01-11-2018, 06:12 PM   #2
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QuoteOriginally posted by unapye Quote
Hello,
I would like to share some observation. I wanted to check the difference between the pixel shift and the single photo mode with a new lens. Pointed the camera at the monitor and made several photos.
I paste one of them and a crop here because I have no idea what it is.



Few observations.
The violet bar appears at different shutter speeds and different apertures, regardless of the SD card and SD slot.
It appears when I move the focus slightly backward or forward, just enough to make the moire disappear.
The bar disappears hovewer when focus is moved significantly and the picture is vague.
The bar disappears when another website is opened
and is coming back when the Google browser is opened. So I open different websites and Google alternately a dozen times and every time when I take a picture of Google browser, the violet bar appears and in the pictures of other sites the bar disappears. It disappears in pictures of desktop, photos, programs also.
Of course it happens by accident. So is it a fault ?
I wouldn't use a computer monitor as a test subject, because the refresh rate (likely 60 Hz) will mess with what pixel shift is trying to do under the hood. I'd bet it's similar to what happens when shooting fluorescent lights at fast shutter speeds. Do you get the same problem a stationary subject? Shooting at a shutter speed slower than 1/60s or 1/50s could also eliminate the artifacts.

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01-11-2018, 06:37 PM   #3
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QuoteOriginally posted by unapye Quote
Hello,
I would like to share some observation. I wanted to check the difference between the pixel shift and the single photo mode with a new lens. Pointed the camera at the monitor and made several photos.
I paste one of them and a crop here because I have no idea what it is.



Few observations.
The violet bar appears at different shutter speeds and different apertures, regardless of the SD card and SD slot.
It appears when I move the focus slightly backward or forward, just enough to make the moire disappear.
The bar disappears hovewer when focus is moved significantly and the picture is vague.
The bar disappears when another website is opened
and is coming back when the Google browser is opened. So I open different websites and Google alternately a dozen times and every time when I take a picture of Google browser, the violet bar appears and in the pictures of other sites the bar disappears. It disappears in pictures of desktop, photos, programs also.
Of course it happens by accident. So is it a fault ?
You might end up with much more impressive results from shooting pixel shifting as it was meant to be used, as, if you were to go outside and shoot a static subject while on a tripod.
My 2C worth.
01-11-2018, 07:01 PM   #4
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Yes its a fault.

A fault that our screens still refresh at 50hz to 60hz and not 1khz.


As Adam said.
Don't worry about it and go out and take some photos.

01-11-2018, 10:29 PM   #5
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Interesting...I have not used Pixel shift. Pixel shift takes 3 shots. I think you have to finish taking all the 3 shots before screen completes one single refresh.
01-12-2018, 01:23 AM   #6
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QuoteOriginally posted by unapye Quote
The bar disappears when another website is opened
and is coming back when the Google browser is opened. So I open different websites and Google alternately a dozen times and every time when I take a picture of Google browser, the violet bar appears and in the pictures of other sites the bar disappears. It disappears in pictures of desktop, photos, programs also.
That it happens only with the Google webpage is strange.
01-12-2018, 02:35 AM   #7
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Thanks for the reply.

Adam, pinholecam note that the picture has a barrel distortion and the violet bar have not.
And here, plastic monitor frame. It is fresh all the time
I also tried 1/90s.

Ex Finn, this is not the only puzzle with my pixel shift, but first things first.

01-12-2018, 06:31 AM   #8
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QuoteOriginally posted by unapye Quote
Thanks for the reply.

Adam, pinholecam note that the picture has a barrel distortion and the violet bar have not.
And here, plastic monitor frame. It is fresh all the time
I also tried 1/90s.

Ex Finn, this is not the only puzzle with my pixel shift, but first things first.
How did you process the file?


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01-12-2018, 07:24 AM   #9
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That kind of result reminds of write errors. This can be due to sd card, sd card slot (damaged or unclean), or within the camera somewhere between the chip and the writing. It could indicate further problems with the chip later on.
But it could also be refresh rate and all of that, as stated above. If you get this bar when taking photos of things other than computer screens, you should worry and take the camera back (or at least notify the shop so you can use warranty later). If this happens only with various computer monitors, then you just found an interesting thing that happens with Pixel shift and digital screens. It could be the pixels confuse the PS to such an extent that it writes wrong data. This could explain why no distortion. PS is not just directly writing data, it is the camera trying to interpret the data. Especially if you have motion correction disabled.
Also, some websites have a "flickering noise" texture. To the naked eye it seems like colour, but if you look closely you can see its actually flickering and noisy. Remember, a computer screen can be doing things that you cant see from a normal viewing distance and angle.
01-12-2018, 07:26 PM   #10
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You have to take a picture of something other than a computer monitor. A monitor is made for the human eye not a camera image sensor, plus I doubt the image is stable enough for pixel shift.
01-12-2018, 08:11 PM   #11
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QuoteOriginally posted by unapye Quote
Ex Finn, this is not the only puzzle with my pixel shift, but first things first.
You made me try it and I be damned, it does work!
I do not have a K1 so that could make a difference... This is a PS shot taken on a tripod of my 43" LG 4k IPS TV running at 60Hz re-fresh.

What if there is something wrong with your monitor and not the camera?
edit: if the frame is "fresh" (providing that I understand this correctly) then that would definitely point to the panel causing your condition?
Or Google skimping on data for just a few milliseconds that our eyes do not register!
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Last edited by Ex Finn.; 01-12-2018 at 08:58 PM.
01-13-2018, 04:18 AM   #12
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If you need screen grabs of things you are viewing on the internet, there are probably easier ways to do it. Certainly not the best use of pixel shift. Have you tried taking photos of static objects or going outside and taking photos of, say, scenery using a tripod? I might try that and process it using DCU with motion correction and see what kind of results you get.

This was a photo from yesterday using pixel shift...

A Sliver of Moon (DFA 15-30)


Generated from my Apple iPhone using tools.rackonly.com

A little better than taking a photo of your computer monitor.
01-13-2018, 12:01 PM   #13
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Adam, This is out of camera jpg, resized in PC only.

GMounk, Please read again my last post above. I have pointed out that the strip overlaps not only the monitor screen but the housing too.

Ex Finn. I meant that the screen flashes and refreshes but the frame around the display does not. It is made from black plastic. Despite this, the purple strip covers it.

Rondec, Thank you for the idea. Nice photo.
01-13-2018, 02:44 PM   #14
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QuoteOriginally posted by unapye Quote
Despite this, the purple strip covers it.
Rules out the monitor then.
01-13-2018, 02:58 PM   #15
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I tried to reproduce this with my screens, but wasn't able to see it.

And you really see it only on the Google web page?
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