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Unable to disable Long Term Noise Reduction in Bulb mode?

Started Sep 18, 2012 | Discussions
nx200USER1 Senior Member • Posts: 1,097
Re: Unable to disable Long Term Noise Reduction in Bulb mode?

I may not be relevant to your 2-3 minute requisite, however I remember that someone said that with digital cameras, noise becomes apparent when the shutter it kept open for long periods of time. The several hours that traditional cameras' shutters would be kept open for. Others said that the solonoid would burn out keeping the shutter open for that long. I can certainly attest to the first note about noise. Im not sure of the term used for it other than noise, but the sensors' 'weak' spots become apparent in my nx200 when I try to capture the stars in bulb mode for 240sec. I couldnt understand what it was, they weren't stars but they looked like it

It turns out that the sensor 'heats up' and these hot spots manifest themselves on a pitch black background as a pixel or several adjacent pixels on the sensor become very bright. There was maybe 3 specs on the photo that I could clearly see. It was apparent on several photos during that session and I think they were all in the same location in each photo.

rudeboymcc Forum Member • Posts: 69
Re: Unable to disable Long Term Noise Reduction in Bulb mode?

The fact that this option exists in the menu means it can be disabled. Can you disable it in normal shutter speeds? (i..e not bulb)

If not, there must be a feature that is enabled which needs Long Term NR (in a similar way that you can't select ISO100 when smart range is enabled).

viking79
viking79 Forum Pro • Posts: 14,157
Re: Unable to disable Long Term Noise Reduction in Bulb mode?

rudeboymcc wrote:

The fact that this option exists in the menu means it can be disabled. Can you disable it in normal shutter speeds? (i..e not bulb)

If not, there must be a feature that is enabled which needs Long Term NR (in a similar way that you can't select ISO100 when smart range is enabled).

The dark frame subtraction (DFS, long shutter speed noise reduction) option is grayed out in bulb mode.  My issue is the DFS is totally broken, because the image is useless on long shutter speeds, say 2 minutes and the image comes out black (the noise reduction isn't working properly).

I see Daniel posted a link to a firmware update today that fixes a bug with bulb mode, so I am going to try that out tonight and see if that fixes this issue.  I would rather not be forced into DFS with bulb, but that is okay as long as I can get a useful image from it.

Eric

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viking79
viking79 Forum Pro • Posts: 14,157
Re: Unable to disable Long Term Noise Reduction in Bulb mode?

viking79 wrote:

rudeboymcc wrote:

The fact that this option exists in the menu means it can be disabled. Can you disable it in normal shutter speeds? (i..e not bulb)

If not, there must be a feature that is enabled which needs Long Term NR (in a similar way that you can't select ISO100 when smart range is enabled).

The dark frame subtraction (DFS, long shutter speed noise reduction) option is grayed out in bulb mode. My issue is the DFS is totally broken, because the image is useless on long shutter speeds, say 2 minutes and the image comes out black (the noise reduction isn't working properly).

I see Daniel posted a link to a firmware update today that fixes a bug with bulb mode, so I am going to try that out tonight and see if that fixes this issue. I would rather not be forced into DFS with bulb, but that is okay as long as I can get a useful image from it.

Oh, weird, the older firmware works fine with DFS and my 12-24mm.  I wonder if it is related to the manual focus lens I was using (for some reason exposures longer than 30 seconds would be almost black, even when a 30 second exposure at the same settings would be brighter).  I might have to look at exif data in my pictures and see if I can replicate the situation with the new firmware.

Eric

-- hide signature --

I never saw an ugly thing in my life: for let the form of an object
be what it may - light, shade, and perspective will always make it
beautiful. - John Constable (quote)
See my Blog at: http://www.erphotoreview.com/ (bi-weekly)
Flickr Photostream: http://www.flickr.com/photos/28177041@N03/ (updated daily)

 viking79's gear list:viking79's gear list
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ABloom New Member • Posts: 2
Re: Unable to disable Long Term Noise Reduction in Bulb mode?
1

Star trail work around Try this.

-set camera to the exposure time (20s)

-set Jjc tm to bulb 1s, interval 22s and repeat infinity(or however many you pics you want)

-stack Photos in say sequator.

Play with the interval time might need a second or two more depending on memory speed etc.

Pic below needs fine tuning but an example. Nx 1000 bortle 8.

james _ Regular Member • Posts: 200
Re: Unable to disable Long Term Noise Reduction in Bulb mode?

i guess someone somewhere might appreciate your response to an 8 year old thread lol

ABloom New Member • Posts: 2
Re: Unable to disable Long Term Noise Reduction in Bulb mode?

👍

Sunscreen
Sunscreen Junior Member • Posts: 30
Re: Unable to disable Long Term Noise Reduction in Bulb mode?

It is appreciated

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