Problem with 1.30? Window Blind Effect Using Live View Electronic Shutter

dcpropilot · 09-29-2016, 10:01 AM - **1 Like**

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.

dcpropilot · 09-29-2016, 10:07 AM

Originally posted by dcshooter

Are you using it under fluorescent light? That's specifically not recommended in the accompanying docs

LED lights...

Gimbal · 09-29-2016, 10:10 AM

Some LED lights pulses as well.

dcpropilot · 09-29-2016, 10:11 AM

But that particular pattern in the photo? Also, it doesn't happen when using the Optical Viewfinder.

beholder3 · 09-29-2016, 10:12 AM

Originally posted by dcpropilot

LED lights...

Try in sunlight. Unless you get it there it's an "light bulb" issue.

vonBaloney · 09-29-2016, 10:15 AM

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?)

Gimbal · 09-29-2016, 10:21 AM

Originally posted by vonBaloney

(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.

Unregistered User · 09-29-2016, 10:26 AM

The effect is due to flickering light source. Lowering shutter speed will fix the problem.

MJKoski · 09-29-2016, 10:32 AM

This was the ill-effect of EFCS like was discussed before in that 1.3 thread.

vonBaloney · 09-29-2016, 12:17 PM

Originally posted by Gimbal

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.

stevebrot · 09-29-2016, 01:38 PM

Originally posted by Gimbal

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.

Originally posted by dcpropilot

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

beholder3 · 09-29-2016, 01:38 PM - **1 Like**

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:

Quote:

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

Gimbal · 09-29-2016, 02:39 PM

Originally posted by stevebrot

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.

phoebus · 09-30-2016, 03:08 AM

Originally posted by Gimbal

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.

Gimbal · 09-30-2016, 03:33 AM

Originally posted by phoebus

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.

On chip, never heard of that. Do you have any examples?

09-29-2016, 10:01 AM - 1 Like	#1
dcpropilot Veteran Member Join Date: Mar 2010 Location: Vermont Photos: Gallery \| Albums Posts: 941	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.

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09-29-2016, 10:07 AM	#2
dcpropilot Veteran Member Join Date: Mar 2010 Location: Vermont Photos: Gallery \| Albums Posts: 941 Original Poster	Originally posted by dcshooter Are you using it under fluorescent light? That's specifically not recommended in the accompanying docs LED lights...

09-29-2016, 10:10 AM	#3
Gimbal Pentaxian Join Date: Apr 2007 Location: Sweden Posts: 2,106	Some LED lights pulses as well.

09-29-2016, 10:11 AM	#4
dcpropilot Veteran Member Join Date: Mar 2010 Location: Vermont Photos: Gallery \| Albums Posts: 941 Original Poster	But that particular pattern in the photo? Also, it doesn't happen when using the Optical Viewfinder.

09-29-2016, 10:12 AM	#5
beholder3 Pentaxian Join Date: Dec 2011 Posts: 3,112	Originally posted by dcpropilot LED lights... Try in sunlight. Unless you get it there it's an "light bulb" issue.

09-29-2016, 10:15 AM	#6
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	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	#7
Gimbal Pentaxian Join Date: Apr 2007 Location: Sweden Posts: 2,106	Originally posted by vonBaloney (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	#8
Unregistered User Guest	The effect is due to flickering light source. Lowering shutter speed will fix the problem.

09-29-2016, 10:32 AM	#9
MJKoski Veteran Member Join Date: Aug 2016 Posts: 1,784	This was the ill-effect of EFCS like was discussed before in that 1.3 thread.

09-29-2016, 12:17 PM	#10
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by Gimbal 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	#11
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by Gimbal 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. Originally posted by dcpropilot 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	#12
beholder3 Pentaxian Join Date: Dec 2011 Posts: 3,112	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: Quote: 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	#13
Gimbal Pentaxian Join Date: Apr 2007 Location: Sweden Posts: 2,106	Originally posted by stevebrot 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	#14
phoebus Pentaxian Join Date: Jun 2013 Location: Buckinghamshire (UK) / Morbihan (FR) Photos: Gallery Posts: 470	Originally posted by Gimbal 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.

09-30-2016, 03:33 AM	#15
Gimbal Pentaxian Join Date: Apr 2007 Location: Sweden Posts: 2,106	Originally posted by phoebus 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. On chip, never heard of that. Do you have any examples?