Author Topic: DBE Tool  (Read 2664 times)

Offline MikeF

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DBE Tool
« on: 2015 May 20 04:57:42 »
I have used the DBE tool on several occasions to flatten the field and remove gradients.  It does a great job at that , however it seems that the resultant image appears to have more noise than the initial image.  Any suggestions on how fix. 

Thanks,  Mike

Offline NGC7789

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Re: DBE Tool
« Reply #1 on: 2015 May 20 05:04:20 »
I think you will find that DBE does not add noise. What happens is that the STF stretch after DBE can be more aggressive than before. This can reveal more noise in the background but that noise was always there. My normal workflow is to attack noise after DBE usually with TGV.

Offline Cleon_Wells

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Re: DBE Tool
« Reply #2 on: 2015 May 20 05:11:28 »
Mike, when I use DBE I always check the Normalize box in the  Target Image Correction tab, this seems to help my low quality/noisy images.
Cleon
Cleon - GSO 10"RC/Canon T1i-Hap Mod, 100mmF6/2Ucam/MG, EQG/EQmod

Offline Nocturnal

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Re: DBE Tool
« Reply #3 on: 2015 May 20 07:02:15 »

Hi,

the artificial image that DBE creates is noise free. It is a calculated surface based on analysis of the sample points. Assuming you are using subtraction this operation does not add noise. As mentioned when image values change like that a stretch may appear to make it more noisy but that is just perception. If you are doing division to do artificial flattening noise is also multiplied and will appear stronger even though the actual SNR was not affected because signal and noise were multiplied the same way.

Show us some sample images if you feel our explanations don't cover your situation.

  Sander
Best,

    Sander
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