K-1 mkII long exposure in camera processing

gerardbaron · 02-26-2019, 02:12 PM

Playing with ND filter with a K-1 mII.
I found that an exposure of 30 secondes in bulb mode takes forever to process in camera before the picture reveals.
I figure out that a 30 seconds exposure takes about more than 15 seconds to process in camera.
A 80 seconds takes at least 1 minutes.
Is it a normal behavior?
Should I change any setup in camera?
Thank you for your help.

Read more at: K-1 MK2 Long Exposure Performance - Page 2 - PentaxForums.com

enoeske · 02-26-2019, 02:14 PM

Originally posted by gerardbaron

Playing with ND filter with a K-1 mII.
I found that an exposure of 30 secondes in bulb mode takes forever to process in camera before the picture reveals.
I figure out that a 30 seconds exposure takes about more than 15 seconds to process in camera.
A 80 seconds takes at least 1 minutes.
Is it a normal behavior?
Should I change any setup in camera?
Thank you for your help.

Read more at: K-1 MK2 Long Exposure Performance - Page 2 - PentaxForums.com

Turn off Dark Frame Subtraction and it will be almost instantaneous (might be called something different, I can't remember)

pschlute · 02-26-2019, 02:22 PM

Originally posted by gerardbaron

Is it a normal behavior?

Yes. Normal behaviour. You can disable it if you want to deal with the noise a long exposure creates yourself.

Adam · 02-26-2019, 02:35 PM

Originally posted by gerardbaron

Playing with ND filter with a K-1 mII.
I found that an exposure of 30 secondes in bulb mode takes forever to process in camera before the picture reveals.
I figure out that a 30 seconds exposure takes about more than 15 seconds to process in camera.
A 80 seconds takes at least 1 minutes.
Is it a normal behavior?
Should I change any setup in camera?
Thank you for your help.

Read more at: K-1 MK2 Long Exposure Performance - Page 2 - PentaxForums.com

The setting to disable is called "slow shutter speed noise reduction". This noise reduction is effective at removing hot pixels that come from sensor hear, but the processing time is roughly equivalent to the duration of the exposure itself.

If image quality is paramount, you can do DFS processing after the fact by snapping a dark frame manually.

Adam
PentaxForums.com Webmaster (Site Usage Guide | Site Help | My Photography)

PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

**UncleVanya** · 02-26-2019, 03:24 PM

As otgers said. Starting at about 30 seconds the camera takes a dark frame of the same duration to remove artifacts created by the length of tge exposure (heat related sensor pixel noise). As Adam said you can manually create your own dark frame to let Lightroom or another tool manually subtract this noise. The key is similar conditions and durations.

gerardbaron · 02-26-2019, 04:21 PM

Originally posted by UncleVanya

As otgers said. Starting at about 30 seconds the camera takes a dark frame of the same duration to remove artifacts created by the length of tge exposure (heat related sensor pixel noise). As Adam said you can manually create your own dark frame to let Lightroom or another tool manually subtract this noise. The key is similar conditions and durations.

How you do that in Lightroom ?

**UncleVanya** · 02-26-2019, 04:52 PM

Originally posted by gerardbaron

How you do that in Lightroom ?

My mistake. I meant Photoshop. And I'm not an expert on the method.

gerardbaron · 02-26-2019, 05:02 PM

Originally posted by Adam

The setting to disable is called "slow shutter speed noise reduction". This noise reduction is effective at removing hot pixels that come from sensor hear, but the processing time is roughly equivalent to the duration of the exposure itself.

If image quality is paramount, you can do DFS processing after the fact by snapping a dark frame manually.

Hello Adam
How do you snap a black frame in photoshop?
Do you create two layers one with the photo and the other one with
the black one and then use mode substrat ?
Gerard

Adam · 02-26-2019, 05:06 PM

Originally posted by gerardbaron

Hello Adam
How do you snap a black frame in photoshop?
Do you create two layers one with the photo and the other one with
the black one and then use mode substrat ?
Gerard

Basically, you subtract all black from the dark frame, which leaves you with the hotspots. Then, subtract the hotspots from the image that was captured. I'm sure there are tutorials online- not sure what the exact filter would be.

**UncleVanya** · 02-26-2019, 05:37 PM

Try posing the question in one of the astrophotography threads or forums if you can't find it here.

DeadJohn · 02-27-2019, 12:26 AM

Originally posted by gerardbaron

Playing with ND filter with a K-1 mII....

You're taking daylight photos with the ND, correct? I think you can just ignore dark frame subtraction for now - you won't notice a tiny bit of noise in scenes that aren't filled with black. Turn off slow shutter speed noise reduction.

Only invest time learning about dark frames if you do astrophotography and night landscapes.

K1N8 · 02-27-2019, 01:50 AM

Is in-camera dark frame subtraction officially documented anywhere?

MJKoski · 02-27-2019, 05:49 AM

K-1 II handles very long exposures just fine without DFS in-camera. 20C ambient temp gives 4-5min easily and 5-15mins in subzero temperature. This is more what MK1 is able to handle although it is fine as well. I think KP and MK2 might use the accelerator to filter out long exposures. KP particularly is interesting case as it beats many FF cameras when doing long exposures without DFS.

**disasterfilm** · 02-28-2019, 09:12 AM

Quick pseudo-related question for y'all - does Long Shutter NR affect the RAW file, or just the JPG?

**UncleVanya** · 02-28-2019, 03:16 PM

Originally posted by disasterfilm

Quick pseudo-related question for y'all - does Long Shutter NR affect the RAW file, or just the JPG?

As far as I understand - both. The subtraction is done before the file is saved. BUT I can't find a citation for this and while I have shot with it on in a number of situations I don't know that I would have noticed it off.

02-26-2019, 02:12 PM	#1
gerardbaron Senior Member Join Date: Apr 2011 Location: Mississauga (Canada) Photos: Albums Posts: 139	K-1 mkII long exposure in camera processing Playing with ND filter with a K-1 mII. I found that an exposure of 30 secondes in bulb mode takes forever to process in camera before the picture reveals. I figure out that a 30 seconds exposure takes about more than 15 seconds to process in camera. A 80 seconds takes at least 1 minutes. Is it a normal behavior? Should I change any setup in camera? Thank you for your help. Read more at: K-1 MK2 Long Exposure Performance - Page 2 - PentaxForums.com

02-26-2019, 05:06 PM	#9
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,594	Originally posted by gerardbaron Hello Adam How do you snap a black frame in photoshop? Do you create two layers one with the photo and the other one with the black one and then use mode substrat ? Gerard Basically, you subtract all black from the dark frame, which leaves you with the hotspots. Then, subtract the hotspots from the image that was captured. I'm sure there are tutorials online- not sure what the exact filter would be. Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

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02-26-2019, 02:14 PM	#2
enoeske Veteran Member Join Date: Jul 2009 Location: Surprise, Az Photos: Gallery Posts: 2,136	Originally posted by gerardbaron Playing with ND filter with a K-1 mII. I found that an exposure of 30 secondes in bulb mode takes forever to process in camera before the picture reveals. I figure out that a 30 seconds exposure takes about more than 15 seconds to process in camera. A 80 seconds takes at least 1 minutes. Is it a normal behavior? Should I change any setup in camera? Thank you for your help. Read more at: K-1 MK2 Long Exposure Performance - Page 2 - PentaxForums.com Turn off Dark Frame Subtraction and it will be almost instantaneous (might be called something different, I can't remember)

02-26-2019, 02:22 PM	#3
pschlute Moderator Loyal Site Supporter Join Date: Mar 2007 Location: Surrey, UK Photos: Gallery Posts: 8,198	Originally posted by gerardbaron Is it a normal behavior? Yes. Normal behaviour. You can disable it if you want to deal with the noise a long exposure creates yourself.

02-26-2019, 02:35 PM	#4
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,594	Originally posted by gerardbaron Playing with ND filter with a K-1 mII. I found that an exposure of 30 secondes in bulb mode takes forever to process in camera before the picture reveals. I figure out that a 30 seconds exposure takes about more than 15 seconds to process in camera. A 80 seconds takes at least 1 minutes. Is it a normal behavior? Should I change any setup in camera? Thank you for your help. Read more at: K-1 MK2 Long Exposure Performance - Page 2 - PentaxForums.com The setting to disable is called "slow shutter speed noise reduction". This noise reduction is effective at removing hot pixels that come from sensor hear, but the processing time is roughly equivalent to the duration of the exposure itself. If image quality is paramount, you can do DFS processing after the fact by snapping a dark frame manually. Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

02-26-2019, 03:24 PM	#5
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,399	As otgers said. Starting at about 30 seconds the camera takes a dark frame of the same duration to remove artifacts created by the length of tge exposure (heat related sensor pixel noise). As Adam said you can manually create your own dark frame to let Lightroom or another tool manually subtract this noise. The key is similar conditions and durations.

02-26-2019, 04:21 PM	#6
gerardbaron Senior Member Join Date: Apr 2011 Location: Mississauga (Canada) Photos: Albums Posts: 139 Original Poster	Originally posted by UncleVanya As otgers said. Starting at about 30 seconds the camera takes a dark frame of the same duration to remove artifacts created by the length of tge exposure (heat related sensor pixel noise). As Adam said you can manually create your own dark frame to let Lightroom or another tool manually subtract this noise. The key is similar conditions and durations. How you do that in Lightroom ?

02-26-2019, 04:52 PM	#7
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,399	Originally posted by gerardbaron How you do that in Lightroom ? My mistake. I meant Photoshop. And I'm not an expert on the method.

02-26-2019, 05:02 PM	#8
gerardbaron Senior Member Join Date: Apr 2011 Location: Mississauga (Canada) Photos: Albums Posts: 139 Original Poster	Originally posted by Adam The setting to disable is called "slow shutter speed noise reduction". This noise reduction is effective at removing hot pixels that come from sensor hear, but the processing time is roughly equivalent to the duration of the exposure itself. If image quality is paramount, you can do DFS processing after the fact by snapping a dark frame manually. Hello Adam How do you snap a black frame in photoshop? Do you create two layers one with the photo and the other one with the black one and then use mode substrat ? Gerard

02-26-2019, 05:37 PM	#10
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,399	Try posing the question in one of the astrophotography threads or forums if you can't find it here.

02-27-2019, 12:26 AM	#11
DeadJohn Pentaxian Join Date: Jan 2011 Location: New York Posts: 4,833	Originally posted by gerardbaron Playing with ND filter with a K-1 mII.... You're taking daylight photos with the ND, correct? I think you can just ignore dark frame subtraction for now - you won't notice a tiny bit of noise in scenes that aren't filled with black. Turn off slow shutter speed noise reduction. Only invest time learning about dark frames if you do astrophotography and night landscapes.

02-27-2019, 01:50 AM	#12
K1N8 Senior Member Join Date: Oct 2018 Posts: 242	Is in-camera dark frame subtraction officially documented anywhere?

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02-27-2019, 05:49 AM	#13
MJKoski Veteran Member Join Date: Aug 2016 Posts: 1,784	K-1 II handles very long exposures just fine without DFS in-camera. 20C ambient temp gives 4-5min easily and 5-15mins in subzero temperature. This is more what MK1 is able to handle although it is fine as well. I think KP and MK2 might use the accelerator to filter out long exposures. KP particularly is interesting case as it beats many FF cameras when doing long exposures without DFS.

02-28-2019, 09:12 AM	#14
disasterfilm Site Supporter Join Date: Aug 2014 Location: Texas Posts: 406	Quick pseudo-related question for y'all - does Long Shutter NR affect the RAW file, or just the JPG?

02-28-2019, 03:16 PM	#15
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,399	Originally posted by disasterfilm Quick pseudo-related question for y'all - does Long Shutter NR affect the RAW file, or just the JPG? As far as I understand - both. The subtraction is done before the file is saved. BUT I can't find a citation for this and while I have shot with it on in a number of situations I don't know that I would have noticed it off.