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what happened to my image

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#1 wheelers4life

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Posted 15 December 2019 - 04:54 AM

This is what I took tonight. I took 14x 300s subs gain at 120 stopped did a meridian flip. took 30x 300s subs gain 120. 4x4 bining for all, 20 dark frames, 100 bias frames, 20 flat frames, and 20 dark flats. stacked in deep sky stacker, used pi for background neutralization, color calibration, and snr. This is what I have left. it seems like I only got the core and not nebulae. Any ideas what happened this has never happened,

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#2 sharkmelley

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Posted 15 December 2019 - 05:08 AM

The image has been clipped by subtracting a value that was too high.

 

Maybe the level in your bias and/or darks is too high.  Check their pixel values.  Were they taken with the same gain and offset as the lights? 

 

Alternatively it could be a processing problem - for instance subtracting bias twice.

 

Mark


Edited by sharkmelley, 15 December 2019 - 05:09 AM.

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#3 james7ca

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Posted 15 December 2019 - 05:26 AM

I agree with Mark and it looks like a processing problem. How did you do the histogram stretch?



#4 GoldSpider

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Posted 15 December 2019 - 10:55 AM

I'd guess this was from something like the black point set in DSS.  Try turning that off and stacking it again and see what happens.



#5 wheelers4life

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Posted 15 December 2019 - 01:31 PM

for some reason I cannot use my bias frames. I have been working on it all morning. I am able to use all lights, darks, flat, and dark flat and get a good result. As soon as i instert my master biase it give the above result. Not sure what happened to the biase frames. This is what I have so far. I think it is pretty cool but am not getting the hang of the processing. I have looked at so many videos and purchased the inside pix insight book.

This image is 40 x 300s subs at 120 gain, 20 darks, 20 flats, 20 dark flats all stacked with deep sky stacker. Processed in pi, and polished in photo shop.

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#6 Stelios

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Posted 15 December 2019 - 01:37 PM

for some reason I cannot use my bias frames. I have been working on it all morning. I am able to use all lights, darks, flat, and dark flat and get a good result. As soon as i instert my master biase it give the above result. Not sure what happened to the biase frames. This is what I have so far. I think it is pretty cool but am not getting the hang of the processing. I have looked at so many videos and purchased the inside pix insight book.

This image is 40 x 300s subs at 120 gain, 20 darks, 20 flats, 20 dark flats all stacked with deep sky stacker. Processed in pi, and polished in photo shop.

Try stacking in PI since you have it. Follow the Inside Pixinsight book and don't use BPP (to better control the process). 


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#7 durak

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Posted 15 December 2019 - 01:39 PM

for some reason I cannot use my bias frames. I have been working on it all morning. I am able to use all lights, darks, flat, and dark flat and get a good result. As soon as i instert my master biase it give the above result. Not sure what happened to the biase frames. This is what I have so far. I think it is pretty cool but am not getting the hang of the processing. I have looked at so many videos and purchased the inside pix insight book.

This image is 40 x 300s subs at 120 gain, 20 darks, 20 flats, 20 dark flats all stacked with deep sky stacker. Processed in pi, and polished in photo shop.

I am not an expert but I believe that your dark flats take the place of bias frames. If you use both dark flats and bias frames, I believe you are basically "double dipping". It should be one or the other. On my 1600mm Pro, very quick fast (<.20 sec) images are wonky so I shoot dark flats instead of  bias.

 

Somebody please correct me if I'm wrong.


Edited by durak, 15 December 2019 - 01:40 PM.

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#8 elmiko

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Posted 15 December 2019 - 02:28 PM

I don't think you need to bin. Try not binning.



#9 wheelers4life

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Posted 15 December 2019 - 02:54 PM

I will give stacking in pi a shot I have never tried that before pi is way confusing to me. I tried bining to see what the difference was I was hoping to get a better fov. But that was not the case I really did not see a differnece. I am trying to get a image like that of a hyperstar, but I understand that would require like 18 hours worth of data. I was thinking using bining and creating super pixles might pull more detail than without bining. 



#10 sharkmelley

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Posted 15 December 2019 - 04:23 PM

I was thinking using bining and creating super pixles might pull more detail than without bining. 

Yes, binning is a way to trade resolution for increased signal-to-noise, allowing fainter structures to be revealed.

 

Mark



#11 OldManSky

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Posted 15 December 2019 - 04:41 PM

I will give stacking in pi a shot I have never tried that before pi is way confusing to me. I tried bining to see what the difference was I was hoping to get a better fov. But that was not the case I really did not see a differnece. I am trying to get a image like that of a hyperstar, but I understand that would require like 18 hours worth of data. I was thinking using bining and creating super pixles might pull more detail than without bining. 

Binning or not won't change your FOV.  The chip size is what determines your FOV -- binning simply reduces the number of effective pixels IN that same FOV.  You lose resolution, and keep the exact same FOV.  



#12 Stelios

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Posted 15 December 2019 - 06:25 PM

I will give stacking in pi a shot I have never tried that before pi is way confusing to me. I tried bining to see what the difference was I was hoping to get a better fov. But that was not the case I really did not see a differnece. I am trying to get a image like that of a hyperstar, but I understand that would require like 18 hours worth of data. I was thinking using bining and creating super pixles might pull more detail than without bining. 

I have never used more than 7 hours worth of data shooting at F/7 (most is closer to 4 hours) and the images are not that bad. F/2 is not the solution to all ills.

 

For stacking in PI, the Warren Keller book goes into painstaking detail. Just follow those instructions. However, as already pointed out, you can use bias frames *OR* dark flats, but not both. Please read this thread where I asked about dark flats. The answers worked, in particular this one.



#13 ChrisWhite

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Posted 15 December 2019 - 08:12 PM

Make sure the bias are shot in the same BIT setting as the other frames.  Sometimes the ZWO driver reverts to 8 bit.  Perhaps this is your problem? 



#14 nimitz69

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Posted 15 December 2019 - 08:17 PM

the 294 does not like bias (extremely short subs), you need to use dark flats instead


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#15 wheelers4life

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Posted 16 December 2019 - 07:11 PM

I used the book by warren keller and went threw the frames with blink, then I created master dark, bias, and flats.  Calibrated lights, and aligned, debrayer, and stacked them according to the book. Other than that this is the same time frame and data as the above picture. Do you think it is any better. I tried to process it in ps a little but not to much help except the saturation and gamma.

Thanks

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#16 wheelers4life

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Posted 17 December 2019 - 02:23 PM

I did an image analysis on my master files for some reason my master flat is bright white. I thing it should be grey. And the master flat has a fairly large black starburst on the right side. Any ideas everything looks good and collimated.


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