M101 help with processing

[Callum1985]

Hi All, 

Newbie here! I have an image of M101 that i have got to a point where i cannot improve this anymore and wanted to know if anybody can help me or if i would just need more exposure time. going by the histogram on the back of the camera at 2mins this was in the centre so i thought extending the exposure time will over exposure and washout, however when stacking the images where a nice dark colour and didnt seem washed at all ! .. should i be paying less attention to the histogram on the back of the camera and could i have increased time to maybe 5mins or more ? (I do have a CLS filter on its way so hoping that this will help with light pollution etc..)im under Bortle 5 skies if that helps at all )  roll on postman!!!!! 

It was taken with:

2 min exposure x 73, darks x20, flats x50, bias x50 iso 800

camera was a unmodified canon 10d, through a skywatcher 200p, guided with skywatcher synguider through a celestron 80mm guidescope mounted on HEQ5 Pro 

I have been using PHotoshop CS5 to process and stacked with DSS however my PS experience is limited any advice help or pointers would be great 

attached is my attempt along with the tiff unprocessed . 

 

many thanks for all help 

 

callum 

Autosave.tif

[wornish]

Good start.

Thanks for sharing your data.

 

Here is a very quick process in PI and PS.

 

 

[Callum1985]

Wow.. That is incredible..  Please could you let me know how you have managed that without the sky going red or noisy? Any help to get that kind of result would be amazing.. Thank you, that has opened my eyes that I have some way to go with learning ps

[MarkAR]

Good effort, looks like there was a lot of sensor noise in your image.

[wornish]

8 hours ago, Callum1985 said:

Wow.. That is incredible..  Please could you let me know how you have managed that without the sky going red or noisy? Any help to get that kind of result would be amazing.. Thank you, that has opened my eyes that I have some way to go with learning ps

There was a lot of noise in the image but it can be minimised.  I did use PI for most of the processing steps. The easiest way to remove the overall red background was to use the Automatic Background removal tool in PI it works very well. PI does have a more sophisticated background removal tool but that takes a lot more time to set up.  I also used PI to stretch the image using its Histogram Transformation process and its Curves Transformation process.  In PS you can reduce the noise using the Noise Reduction Filter, and also using a Brightness and Contrast adjustment layer.