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Combining images in DSS

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#1 AKHalea

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Posted 24 November 2017 - 10:30 AM

Another noob question for the experts - I use DSS for stacking. I have tiff files of same objects taken at different image scales. Can one combine them in DSS to improve SNR? For example, I have an unprocessed tiff file taken at 600mm focal length with the SW80ED scope w/o the focal reducer and another unprocessed tiff file with the same scope but with the 0.8x focal reducer (focal length 480mm). Is it possible to combine these two? If yes, what is the method to do that? Thanks in advance ..... Anil


Edited by AKHalea, 24 November 2017 - 10:34 AM.


#2 happylimpet

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Posted 24 November 2017 - 10:57 AM

Nope, DSS cant combine different scales. I understand other software can - I recall Registar being mentioned....there are probably others.



#3 zxx

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Posted 24 November 2017 - 11:14 AM

I watched Trevor do this in one of his youtube vids    Astrobackyard   not sure what program he used 



#4 xiando

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Posted 24 November 2017 - 01:57 PM

Another noob question for the experts - I use DSS for stacking. I have tiff files of same objects taken at different image scales. Can one combine them in DSS to improve SNR? For example, I have an unprocessed tiff file taken at 600mm focal length with the SW80ED scope w/o the focal reducer and another unprocessed tiff file with the same scope but with the 0.8x focal reducer (focal length 480mm). Is it possible to combine these two? If yes, what is the method to do that? Thanks in advance ..... Anil

No.

 

However... If one can accurately determine the image scale difference, one could theoretically batch enlarge the smaller set (0.8x), then batch crop to fit the dimensions of the larger (1x) set, then stack. I don't know that it'd improve the SNR though.

 

Seems to me it'd be easier to stack separately and then merge using layers after a rescale operation on the 0.8x set in PS or similar.


Edited by xiando, 24 November 2017 - 01:57 PM.


#5 PhilHoyle

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Posted 25 November 2017 - 10:46 AM

Images Plus can do this.  However, each image must be calibrated separately.  You can only use one set of calibration images at a time and they must be the same size and type as your light images.

 

Phil




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