looking at your image i do not agree..
You are comparing an image from an experienced user, experienced in editing, using a cooled camera and a RASA, to dslr shots with zoomlenses, edited by newbies like myself.
That's NOT what I'm doing.
I'm looking at how much of the spectrum an LPro cuts out. It's substantial. That will lower snr about as much as cutting out some of the light pollution will raise it.
See this thread about galaxies, it applies to other broadband targets like M45.
"if I want to go deep with a luminance image of a faint field of galaxies - the reduction of light pollution - which does happen - is not enough to compensate for the loss of galaxy signal - which also happens."
"I never liked LP filter because it messes up color balancing (i.e. too many stars were too bluish) so I rely on processing to remove or reduce gradients with PixInsight and works well."
"I dropped LP filters a few years ago, after finding they often hurt SNR in as many cases as they may have helped."
"All my light pollution filters have made their way over to my guide scopes. I stopped using them on my main imagers, but they can help with picking out stars in heavy LP areas."
Most of the effect of light pollution is reduced by gradient reduction in processing. These filters make sense on emission nebulae (which don't emit much in the gaps). ONLY. Even then they distort star color, but for emission nebulae, the gain in contrast is worth it.
The image was just to drive the point home. <smile>
Bottom line. Pretty much all serious imagers use gradient reduction. Some will additionally use a broadband LP filter, some won't. Of those who do, pretty much all of them use them on emission nebulae, only.
Edited by bobzeq25, 08 March 2021 - 02:56 PM.