[OneCosmos (Chris)]

Now, even before reading this I know you are all immediately answering the question in the negative - and, in truth so am I, but.... read on.

My observatory is in Nundah, an inner city suburb for sure and as light polluted as any other in Brisbane. Actually, the milky way is easily visible and the naked eye views aren't anywhere near as bad as from my home town in England which has a population of only about 30,000!

The observatory is really taking shape now and I am having enormous success making imaging as effortless as possible - which means automation. My view is that anything that is a chore will act as a deterrent against bothering. I am happy to report it is now about as effortless as it can ever be.

I still do, of course have to deal with the light polluted skies. I tried imaging without a CLS filter and results were rubbish. I acquired a CLS and the transformation was astounding.

I won't elaborate too much here in words, I'll let the pictures do the talking. Take a look at the screen grab from PixInsight attached. Each of these images are simply RAW FIT files. They are single 10 minute subs. The one on the left is M42 taken without a CLS filter and under it NGC253, also without a filter. Hopeless.

Next comes Eta Carina with the CLS filter on a decent night, later in the evening with no moon. The next one, for comparison is Eta Carina earlier in the evening (more civil light pollution) and a really bright moon high up in the West. Finally, I have included M20 taken from Astrofest - a pretty dark sky by most people's standards.

I have tried to make sure that all of these subs can be compared the same so the left sliders are moved to the extreme left edge and the middle slider is moved to the right to the same degree - you can see this in the screen transfer function also shown in the screen capture.

I am finding it really hard to accept the empirical evidence that Nundah with as CLS is better than a dark site without, so someone, please enlighten me as to what I'm missing.

The rationale is that if the vast majority of the light pollution is Sodium or Mercury then it really doesn't exist as far as the camera is concerned, leaving little else.

I have also included a processed version of the Eta Carina, which is comprised of just 12 x 10 min subs, flats, darks and bias frames subtracted. All processed exclusively in PI. Poor processing aside (I need to get better at that), the result looks as good to me as anything I might get from Astroest!

Comments welcome.

Chris