DaveS

I think that for galaxy imaging you will need a better mount than an HEQ5 unless you're going for bigger targets or galaxy groups (Leo Triplet, Markarian's Chain). If you want FL *and* a refractor then the moment arm becomes an issue, especially when you hit the 1 metre range.

AstroArt will do the same, plus has a nifty Remove Line tool.

A little 500gb PCIe SSD. Small but fast, hopefully will speed up stacking. At the mo all my astro files are on a general drive, now I can put them on their own.

Acme thread table From dad's 1943 "Machinery's Handbook".

Well, I just made some calibration frames for the H-alpha data. It did make a difference to the Hydrogen stack, but when I added it to the existing Red stack I could see little effect. I may try doing a DDP on the individual stacks before Trichomy but I've encountered problems with colour balance doing this in the past.

Thanks Steve. Not sure how to do HDR in AstroArt, which is all I use ATM, though I will download GIMP again, now I have a larger boot drive. I can do masks in AA7 though. will look into it. Theoretically (Yeah, right) a big dollop of *good* H-alpha might help define the spiral arms in M65 and 66. Looking at the H-apha data that I captured it looks like my autofocus offset for the Hydrogen filter was off as the stars look bigger than they should with a 3nm filter. If it *was* out of focus that would also explain why the signal was so weak.

Thanks Geof. Getting the background to neutrality has been a real test of my control, as well as colour acuity, even with a calibrated wide-gamut monitor. I think I'll leave this here, accepting the slight blue cast. Maybe getting more data will help, if it's of good enough quality, no point in trying to add dodgy data as I found out the hard way with 6+ hours of duff Hydrogen that just messed up the Red channel and would have been better spent getting RGB or L data instead.

Let's see how this version compares. Used Colour Curves again to get rid of the red background mottling and used Histogram Stretch to adjust both Black and White points. This may be as far as my processing skills can take this data. If I should get a significant amount of new data I will start a new thread toavoid confusing this one. Hmm...Still a touch Blue, and a brighter background than on my monitor, possibly a colour space problem.

OK, I got some calibration frames and ran stacks with properly calibrated data. This is the result Still looking a touch blue on here, was looking neutral during processing, but there was a rather nasty red mottling gradient that was proving obdurate. Tried to put the Black Point between the last two versions. Will go away fro a bit before having another go.

After watching "How to Make" I think it should be compulsory viewing for all Design and Technology students.

Nit-pick away! One big issue I had was from using just one set of Flats for all the channels. I have now captured individual Flats and matching Dark Flats for each, so hopefully will have a cleaner background to work from. There are also a few more clear nights forecast so will hopefully get more LRGB data. To avoid overloading the thread with images I will wait until I have something definite to post.

I'll watch "How to Make", following.

Got BBC4 on, will watch again.

Thanks Bob. Yes, the tail is faint, more so than I expected, though hopefully showing clearer on the second version. More work needed.

I did a medium Black Point version that looks better, but I think I'll wait until I've assembled something with real Flats and Dark Flats before posting another image. Hopefully it may be the definitive version unless I get a shed load more data.

Thanks Geof. Yes, I did brighten the background a tad more than perhaps I should have, but I wanted to see just how much of the Tail was actually there, more than I thought. Will bite the bullet and take a comprehensive set of Flats and Dark Flats.

This is with the Black Point lowered, curves applied in Histogram Stretch and another Denoise. Do need proper flats, as there's a nasty great dust bunny showing. I'm also seeing a bit of a green tinge in the background.

Thanks. The Tidal Tail is fainter than I thought it was going to be, perhaps at a truly dark site it might show more. If I raise the black point there is more of the tail showing, but also a heck of a lot of noise, plus uneven background colour mottling. Maybe actually using the right flats for each stack, instead of being lazy and just using a set of Red flats will help. ATM it's too light / warm but later I may have a go at getting the real ones.

And it's *still* not right. 130mm f/7 TS Photoline triplet apo / ASI 1600 in Max DR / Baader LRGB filters on ASA DDM 60 3 Hours Blue and Green in 600 sec subs, 1 Hour Red in 300 sec subs (A mistake in exposure settings) plus 2 Hours Red in 600 sec subs, 5 Hours Luminance in 600 sec subs. Sigma Add stacking in AstroArt 7, Gradient Removal and align All. Luminance given DDP, Histogram Stretch and Denoise. RGB combination then DDP, Histogram Stretch and Denoise. Finally LRGB synthesis, crop, colour Curve (To reduce a green tinge), Saturation Boost and final Denoise. The Tidal Tail off the Hamburger is proving elusive. Although I can see it in the stacks (Especially the Luminance) during processing, in the final stack it's almost invisible. Need more data, but realistically at least the same again, but I doubt if I'll get it.

That's the other end of the spindle that has the pinion on it. Sorry but you're stuck with it unless you want to take a hacksaw to it (DON'T!).

Oh, I did recalculate the offsets from the Luminance filter, which I set as the one for Sequence to use for plate solving and autofocus, and the results look to be fine. I may get autofocus results for the other filters, but not sure how much better they would be, if at all.

OK, I take your point. I already have offsets from the Red filter, so I could recalculate them for the L.

On Now!

On in 12 mins

Thanks both. ASA Sequence (NOT SGpro) insists on using just one of the filters for both plate solving and autofocus, then applies an offset (Which I have to determine) for the focus position of the other filters. A slight complication is that currently in my ZWO wheel I have Baader LRGB filters, which are 2 mm thick, and an Astrodon H-alpha which is 3 mm so there's a focus shift due to the wavelength plus a shift due to the increased optical thickness. I think I will have to run some autofocus routines tomorrow night before any propper imaging.