M101 from SGL5

[SteveL]

This was the original target for the TS OAG equipped 190 MakNewt, but its been a chore to get this processed. Playing with the other data (M13, NGC7023) has helped me learn a little more about the sky conditions over the two nights, plus I hadnt got Maxim to guide and dither correctly (used PHD instead), it that has caused some issues when stacking.

Anyway, here it is.... I can now see why its a hard target to get good data for, the faint arms really are very faint, and any moisture or muck in the sky will fade them out. I`ll get some more data on this when I can, but I am happy with this as a real first light with the TS OAG (even it is the last of the lot to get processed). Its a bit noisy, the faint bits have had a bit too much noise reduction, there is some gradient showing in the corenrs for some reason, but I dont think this current set of data going to get any better looking than this....

Mount: EQ6 via EQMOD

OTA: Skywatcher 190 MakNewt @ f/5.3

Guiding: TS OAG + Starlight Xpress Lodestar

Imaging: Starlight Xpress M25C + MaximDL, 9×900s (usable), Hutech IDAS LPR (101 bias, 101 flats)

Orchestrated: CDD Commander

Stacked: DeepSkyStacker

(Click on image for larger version)

Full Size Crop

[Coco]

Whoah!... very nice indeed..

the un cropped version is a cracker!

Guy

[MartinB]

Beautiful sharp detail in there Steve. The dim outer areas look a little pushed on the crop but fine on the full size image

[albedo0.39]

Love the uncropped image.. very relaxing !

[Brunty12345]

wow, thats a nice image 0.0

[ollypenrice]

Okay, there is noise but on the right, or slightly lower right of your image there are traces of those faint outer arms that are very rarely seen in images of M101. They really are faint so good capture. (In one of Harry Page's posts he implied that he was on the hunt for those arms in one of his ultra marathon runs so we will see what he comes up with!)

Olly

[Euan]

Good image Steve, shame about the gradients though

Have you got the IDAS further away from the CCD because of the OAG?

I had similar issue with putting it in front of any focal reducers I was using, although they were more radial-type gradients. When I started using a filter wheel and got it closer they went away.

[SteveL]

Filter to CCD distance hasnt changed in any way, the OAG is before the filter drawer, and the OAG replaces the M48 to T2 adapter I had inline anyway. The whole thing still focuses at pretty much the same draw tube distance as it did before.

Am wondering if the gradients are fighting because of a meridian flip in the middle. I`ll see if I can restack only those form the same side and see if that helps.