Problem for Canon Unknown Noise

[kenlan]

I used a Canon EOS M to take 27 pics (2 mins per each with Ha Filter) and stack by ImageIntegration.  The pic have pattern inclined line noise.  Could you please help me to fix it? Any method to remove it?

Many Thanks

[pfile]

probably these exposures are too short - with unmodified DSLRs hardly any Ha light makes it thru the IR filter on the sensor.

you can use cosmetic correction to clean up the sub exposures - you are looking at hot pixels displaced by the registration process. but probably your signal is barely above the noise floor.

rob

[kenlan]

I used a modified camera EOS M, nothing happened before but last night I took another set of pics that appear, so I dunno why!

[pfile]

well if you are using darks, perhaps the temperatures do not match.

at any rate this 'diagonal rain' noise is very common in systems where there is either differential flexure between the guider and imager, or polar alignment is bad. anyway you can try CosmeticCorrection to remove the hot pixels.

rob

[kenlan]

Thanks Rob, I will try !

[kenlan]

I just tried cosmetic correction, canon banding reduction; the result is the same! Useless!  I just trash these data!

[pfile]

CBR can only fix banding that is parallel to one of the axes of the sensor (i can't remember which one now)...

when using cosmeticcorrection did you use the realtime preview to adjust the hot pixel slider?

anyway i do think longer subexposures are needed...

rob

[kenlan]

Yes, i did but did not fix it! Anyway, thx for your help; I only take it again.