Moon pollution

[Mamsoth]

Just a quick question. I am a long time observer but new to imaging, I was out getting some captures of m42 the other night with an atik 2-hs, there was a 90% full moon only 30 degrees to the north of m42 and I was still quite happy with the images I got (considering what I was expecting). When there is no moon in the sky at all ,can I expect a dramatic improvement to the image? I mean, I know there will be an improvement but I was wondering if anyone could quantify it with some actual images.

If anyone has any specific examples they could show of a particular object imaged with and without moon pollution that would be most helpful.

Thanks guys and clear skies

[AndyUK]

Hmmm... I can show you an image (horesehead / flame nebulae) WITH moonglow, but can't show you one without (yet), although I've been told (and expect!) that my rig will do much better than this without the moon about... Please see this thread:

I was expecting to take 600s subs, but after checking the histogram, had to drop down to 180s in order that the RGB Channels weren't clipped... and because of the low maximum exposure the "moonglowed" sky was allowing me to take, I didn't have enough signal to capture the subject without the image having to be WAY overstretched (please also excuse the lack of flats - This was also my 1st time out with my modded DSLR, which seems to have introduced a lot "cr*p"!)

I'm not sure if this helps / answers your query, but as I don't have any narrowband filters, I shan't be trying to do anything on DSO's with a burning moon again...

[mark7331]

Here are a couple of single exposures, both of 300 seconds at -5c, of M27 with the same setup. I think you can see the difference in the raw data. The left frame is with a full moon and the right is with no moon. I hope this helps.

Mark

[Demonperformer]

I think you can see the difference in the raw data.

Just slightly! Thanks, Mark, that is a really interesting comparison

[AndyUK]

Yes - That's a VERY self explanatory comparison! Thanks from me too!

[Mamsoth]

Thanks for the replies, wow that is quite a dramatic difference on m27. The next clear night we get I'm going to really see what this atik 2-hs can do. After m42 I'm honing in on ngc 2392, by the looks of it, once that full moon has subsided, i could well expect a real improvement in image quality.

Thanks again and clear skies

[Catanonia]

Nice comparison Mark