Creating a flat frame issues.

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denababy
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Creating a flat frame issues.

Post by denababy »

Hi everyone we have had a few days of clearish skies so I took the opportunity to image the Sun but when I loaded my flat frame onto the surface layer it was a real mess in that the image looked reversed and where it should have been black sky it looked very contrasty and the surface was various shades of misty grey to black. I polar aligned very carefully and the image on the screen never moved one iota. I have looked and looked at my settings in Sharpcap but can see nothing. I took a video of the proms after achieving focus on the surface, I then moved the gain to max so that I could see any proms, Gamma is not on Sharpcap, took a 500 frame vid, moved the gain back so that the surface was ok and took another 500frame vid, I then defocused and without touching anything I took a 300 frame flat. Without the flat loaded the surface image was fine, it was only when I loaded the flat did things go wrong. My camera is a wzoadi120mm the scope is a Lunt 50 the software is Sharpcap, Autostakkert and Photoshop cs 2. If I knew how to load a pic I would. Has anyone else had problems like this?


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Re: Creating a flat frame issues.

Post by PDB »

Where are you loading the flat? If you do that in CS2 that is wrong, should be loaded in Autostakkert before you do the stacking.

To upload a picture use the attachments tab -> add files, select the file on you computer, and use place inline:
Screenshot.png
Screenshot.png (11.73 KiB) Viewed 1265 times
Screenshot2 .png
Screenshot2 .png (14.65 KiB) Viewed 1265 times
P.


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Montana
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Re: Creating a flat frame issues.

Post by Montana »

First you need to load your flat 'video' in Autostakkert and from the drop down menu at the top 'create master flat' and save it. Then load your solar 'video' in Autostakkert then before proceeding with step 2, go to the drop down menu and 'load master flat' then proceed with step 2 and 3. If you have black on your flat you will struggle as it tends to give white in the final image. I tend to move to an area of solar surface which is as uniform as possible (no black space) take the flat and use that. It is more important that you don't change the imaging train, not the area you image. I take one and use it for all that were taken that day on the same magnification regardless of whether an image has black space on it or not.

Also as an aside, if you want to change the exposure, change the exposure, don't use gain to change the exposure. Using gain is just increasing noise not exposure. Although you can use the gain to get a slower exposure time but use it mildly and only when you have to.

Alexandra


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MalVeauX
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Re: Creating a flat frame issues.

Post by MalVeauX »

Here's a tutorial on how I apply flats calibration in AS!2:

https://youtu.be/G-41RMTCdTE?t=12m24s

Very best,


denababy
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Re: Creating a flat frame issues.

Post by denababy »

hi there I am now using my laptop instead of the Ipad to see if I can load a pic.


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