Help with noisy data

[JohnC64]

Hi everyone,

Had a very good night on Friday, Got the guiding working (at last)with a QHY5 and a 400mm camera lens and took images of M81&m82, M27 & M42. The only downside was I left the camera on ISO 3200 and consequently all my images are as noisy as hell. Is there anyway I can rescue the images in post processing. I have had a tweek in DSS but find that if I move the sliders to get rid of the noise, I also reduce the signal.

Does any one have any hints & tips on noise removal

below are a couple of stacked and processed images

Cheers John

Images taken with MN190, and an Olympus EPL1 about 20 x 60sec subs

[Cloudwatcher]

Hi everyone,

Does any one have any hints & tips on nose removal

Cheers John

I would strongly advise against nose removal.......... could be a messy business........

As for the images,they do not look very noisy to me. Try a little subtle blurring and perhaps increase the saturation?

All in all though they are good,well framed shots....

[JohnC64]

Many thanks once again for rescuing my Pictures:icon_salut:

Damn someone spotted my type before i corrected it

Cheers John

[malc-c]

Don't know much about your camera, but my Olympus E500 was awful for astronomy work, with so many hot pixels even on short exposures, but your images do look good to me, so I guess it must be model specific.

[JohnC64]

Hi Malcolm,

The EPL1 is a Micro4/3rds camera with the sensor right behind the lens. It uses a NMOS chip instead of a CMOS chip which does make it stightly more noisey but I find that i can get rid of most of the noise if I keep the ISO to 800 and don't take subs over a minute. Not Ideal but it is my best camera at the moment. Still saving for a cooled ccd of some sort to take the next step in imaging quality

Cheers John

[dph1nm]

Note that ISO isn't (very) important when taking astro shots. ISO3200 is basically ISO800x4, so if you divide the numbers in your ISO3200 image by 4 you should get roughly the same noise as if you had exposed at ISO800 in the first place (I am assuming you are using RAW images).

NigelM