Hi, I have been watching a video (solar processing using Autostakkert and imppg, by Highpoint Scientific) in it there is the creation of a calibration flat, which is basically an out of focus shot of the Sun surface, the chap uses a software named SER Player and Photoshop.The chap creates a master calibration in SER then imports them into Photoshop, he then flattens that file. It’s difficult to explain but there is no where I can find to explain or show how to open those files in AP and then how to flatten them. I understand this post seems a bit gibberish but it may be best if the Highpoint video is watched then maybe someone can come back with advice. Thanks.