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A very nice deep version of NGC6744. I have imaged this one a few times and its quite faint. It also seems a bit harder to get good autoguiding that far south as well. Plus its quite low even at its high point so seeing can be considerably worse down there.
A couple of points. There is a tinge of excess green in the image throwing off the colour balance a little. HLVG free plug in for Photoshop cleans it up as does SCNR in Pixinsight. I think green is a common issue even at dark sites as that is the common colour of airglow in our neck of the planet. Doing a lot of nightcapes has revealed to me just how much nightglow is commonly around. I see it quite a lot at my dark site and sometimes its really strong. I often wondered why I would get excess green at my dark site despite virtually no light pollution. Doing nightscapes showed me why.
The other is the black point. The background on my monitor seems very close to clipped. Its not but there is no room for the usual charcoal background sky.
Its a processing choice but there is also a bit of room left to lift the galaxy in this image. It holds up well to processing which shows how strong your signal is from all those hours and 20 inches of exposure. But that's your processing choices and to my mind neither right nor wrong but there is more left on the processing table should you wish to accentuate it more.
Do you think there is a gain from 30 minute subs? Some of the stars seem overexposed yet they are not super bright stars. But then you have gotten very deep. Would 10-15 minute exposures have worked better though? What's your take on that?
RBI on a focus star? Is that an Apogee issue? Are the focus stars too bright/saturated? I don't see RBI on my 16803 unless its something super bright like the lights on a passing low jet. Perhaps that is something adjustable like the gain?? (a driver improvement perhaps). As you say a large enough dither would do it but will that unsettle your autoguiding?
Anyway just my thoughts on an already excellent image.
I wonder if our Milky Way has an arm that swings up to the LMC like that?
Greg.
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