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09-29-2016, 10:01 AM - 1 Like   #1
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Problem with 1.30? Window Blind Effect Using Live View Electronic Shutter



I don't understand exactly why this is happening, but there appears to be dark bands on my K-1 when using the LV Electronic Shutter....I observed this after installing 1.30.

09-29-2016, 10:05 AM   #2
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Are you using it under fluorescent light? That's specifically not recommended in the accompanying docs
09-29-2016, 10:07 AM   #3
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QuoteOriginally posted by dcshooter Quote
Are you using it under fluorescent light? That's specifically not recommended in the accompanying docs
LED lights...
09-29-2016, 10:10 AM   #4
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Some LED lights pulses as well.

09-29-2016, 10:11 AM   #5
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But that particular pattern in the photo? Also, it doesn't happen when using the Optical Viewfinder.
09-29-2016, 10:12 AM   #6
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QuoteOriginally posted by dcpropilot Quote
LED lights...
Try in sunlight. Unless you get it there it's an "light bulb" issue.
09-29-2016, 10:15 AM   #7
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Yep, it is the lights -- you will probably only get it at certain shutter speeds so compare apples to apples. (And I don't think you are using an electronic shutter unless doing pixel shift on K-1?)
09-29-2016, 10:21 AM   #8
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QuoteOriginally posted by vonBaloney Quote
(And I don't think you are using an electronic shutter unless doing pixel shift on K-1?)
That was true yesterday, but today we have firmware 1.30 and can use an electronic shutter in live view.

09-29-2016, 10:26 AM   #9
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The effect is due to flickering light source. Lowering shutter speed will fix the problem.
09-29-2016, 10:32 AM   #10
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This was the ill-effect of EFCS like was discussed before in that 1.3 thread.
09-29-2016, 12:17 PM   #11
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QuoteOriginally posted by Gimbal Quote
That was true yesterday, but today we have firmware 1.30 and can use an electronic shutter in live view.
Aha. But still an effect I can get with mechanical shutter under the right lights at the right shutter speed, so does electronic shutter (first curtain only I guess?) make it worse -- rolling shutter problem? I suppose it would.
09-29-2016, 01:38 PM   #12
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QuoteOriginally posted by Gimbal Quote
Some LED lights pulses as well.
All LEDs pulse and the better light sources phase the pulses to minimize flicker. High-end studio LEDs have little or no detectable variation for photographic purposes. Common lamp or room lighting...not quite so good.

QuoteOriginally posted by dcpropilot Quote
But that particular pattern in the photo? Also, it doesn't happen when using the Optical Viewfinder.
The pattern reflects the non-global aspect of how the shutter opens. Based on your example, I would guess that the number of stripes indicate the number of zones that simultaneously go live and the attenuation the amount of time it takes to "open" the shutter.


Steve
09-29-2016, 01:38 PM - 1 Like   #13
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Learn:
image processing - Horizontal banding (flickering) due to electronic rolling shutters - Signal Processing Stack Exchange
and
http://www.ledsmagazine.com/articles/print/volume-12/issue-11/features/flick...ustration.html

Fuji on the subject:
QuoteQuote:
Band-like unevenness may occur in shots taken under fluorescent lights, other flickering or erratic illumination.
Re: Any limitations XT-1 Electronic Shutter: Fujifilm X System / SLR Talk Forum: Digital Photography Review
09-29-2016, 02:39 PM   #14
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QuoteOriginally posted by stevebrot Quote
All LEDs pulse and the better light sources phase the pulses to minimize flicker. High-end studio LEDs have little or no detectable variation for photographic purposes. Common lamp or room lighting...not quite so good.
No they don't, if they are feed DC they don't flicker. Unless you mean that there exist no such thing as a perfect DC because there is always some ripple, even from a battery if you look close enough.
09-30-2016, 03:08 AM   #15
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QuoteOriginally posted by Gimbal Quote
No they don't, if they are feed DC they don't flicker. Unless you mean that there exist no such thing as a perfect DC because there is always some ripple, even from a battery if you look close enough.
Yes they do, if they are high output (ie any used for lighting) - the pulsing is generated 'on-chip' to reduce current consumption and over-heating. The output appears bright to the eye, because the frequency is high enough to not detect the flicker and the eye/brain is fooled by the peak output. They spend more time 'OFF' than 'ON'.

The indicator LEDs of old (and probably now) were DC and didn't flicker.
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