IC405 Canon6Dstock DeepSkyLumicon APMfltnr 1155mmFL 5minISO2500 5-AutosaveAverage with a 152mm A+M Refractor(OfficinaStellare) for five RAWMonochrome Autosave images thru MaximDL Pro V6.16 on Jan.11 , 2019 while the Moon was in the West and IC405 was in the East which might reveal the 'off-center glow' in the image if 'collimation' isn't correct.... but the 'off-center glow' looks like it's centered OK and stars seem to be 'focused' ok throughout the image , which isn't cropped to show possible vignetting in the corners . The images were Average stacked in MaximDL Pro V6.16 and then put into "ImagesPlus" to work on it with 'DDP Stretch' first and then the 'Frequency Filter' to remove the 'sine waves' using the 'Show Spectrum Mask' then press 'Apply' and then using the 'Low-Pass' and 'Cut-Off at .5 ' which shows the 'sine waves' to be smoothed out and then 'uncheck' the 'mask' and press 'Apply' and the image will have a smoothed nebula . In "ImagesPLus" they have tutorials and the 'Frequency Domain Concepts' has a lot of info and the links to more pages on how to use the 'Frequency Filter' . It says with the 'Frequency Filter' you 'open' it and it's default is 'Low-Pass' and then 'check' the 'Use Spectrum Mask' and press 'Apply' and the image is transformed into a 'spectrum' image with a 'glow' in the center and 'tiny ring circles' from the center to the edges that are easily visible and these represent the 'sine waves' in the image that you want to remove or fade away to make a smooth image . You move the 'Cut-Off' slider about halfway to the right or more and you will see the 'rings' fade away . Then you 'uncheck' the 'Show Spectrum Mask' which is the third 'mask' option to the right and then press the 'Apply' button and the image will be smoothed in the 'Low-Pass' low frequencies and the slight coarseness will smooth away . This command you would use after 'stacking' and 'DDP Stretch' to reveal the image . x The small jpgs show an 'off-center' M33 from a month ago , and the other is a corrected 'off-center' IC405 image from Friday nite Jan. 11 , 2019 which shows the result of the 're-collimating' I did to the Telescope with the 'Refractor Collimator' I got from Agena.com for $27.00 .x
