DaveS

OK, checked with a hand mirror and there is no centre spot on the secondary, as expected.

Although I think my ODK 12 is in reasonable collimation I would like to be able to check without having to use a precious clear night in order to do so. OOUK recommend a Catseye collimator, but looking on the @FLO website they only run up to f/6, whereas the ODK runs f/6.8. I can see many other options ranging from "pricey" to "how much?!" but am unsure as to their suitability, partly as I'm not sure about the visibility of the secondary through the corrector, and whether it has a centre spot. The very expensive Hotech job with multiple lasers looks to be a non-starter (Fortunately for my bank balance) as the first step is to remove the secondary. Does anyone have any suggestions? I can't afford to buy several instruments, one after another, in the hope that one of them will work.

You can bin mono CMOS, it's just done in software so not quite the advantage of hardware binning CCD.

Um, yes. Just re-read the blurb in RT, they do credit Harriot.

There have been complaints about the background music in Radio Times. But what's worse is that it looks like next week's episode has been bumped off the schedule bu bloody FOOTBALl . Argh, it's enough to make one spit . Just shows the beeb's bloody priorities.

This Sunday on BBC 4 at 8.30 pm Note: note the usual 10 o/c. Telescopes Through Time, from Galileo to Hubble and the James Webb telescopes.

I've been having another play with the data. From the individual coregistered channels I applied an Erosion filter to reduce the star sizes, followed by a more careful DDP with attention to the star cores and a Richardson Lucy deconvolution using a Gaussian Kernel. After RGB synthesis I applied the Luminance I had worked on earlier to produce a LRGB image. A mild saturation boost was followed by a single colour attenuation to remove a touch of excess green followed by a mild Unsharp Mask. I dunno. I still think I'm going round and round the bullseye without quite hitting it. I have so many versions of this it's making my head spin. It's proving very easy to blow out the star cores or blow out the galaxy core or end up with "Cartoon Colours" in NGC 7331. Going to take a break and come back in a day or two, but if anyone has further suggestions I would be grateful.

Oh my, that *is* deep! Especially around Pickering's (Should really be Fleming's) Triangle, which always looks more like a tree to me.

Oh yes, I do like that!

Thanks Martin. Still looking at this with a view to bringing up the star colour without trashing everything else. Also experimenting with some of the tool settings in AA8 in an effort to be more subtle in the processing.

If you think waiting 10 sec for a download is a pain, try waiting the 30 secs it takes for my G3 16200 to download

Yes, I did my "O" Levels at the change from cgs to MKS, SI.

The centimetre isn't an SI unit. Millimetres and Kilometres are SI as they are multiples of 10^3.

I managed to capture some more data on this, so now 30 subs each R, G, B (In G2v calibration) totalling 18 hr 45 min and 72 subs Luminance totalling 12 hr. not sure at the moment how much ended up in the final stacks as I had AstroArt reject subs with elongated stars, fuzzy stars (High FWHM) or high sky background. The Luminance stack was cropped to remove alignment edges followed by Gradient Removal and DDP with a "soft" High Pass" setting and Richardson Lucy Deconvolution. The RGB stacks were brought into the Trichromy process and aligned before being cropped and the RGB channels separated for gradient reduction. Again a "soft" High Pass DDP was applied followed by Richardson Lucy deconvolution. Close attention was applied to the histograms during this. The individual RGB stacks were now brought back into Trichromy before being Coregistered with the Luminance. Several rounds of Histogram Stretch followed to bring the range back to 16 bit before Colour Curves were applied to bring out the Core / Arms difference. There was an Unsharp Mask in there somewhere and a final Histogram Stretch just to bring up the background a touch. Phew! And I'm still not happy. There are some dark halos that are proving troublesome while still enhancing the detail. C&C welcome, together with any suggestions as to how to proceed from here.

I've been out in dressing gown and slippers to shut up after imaging, around 3-4 in the morning a few weeks ago and seeing the sky very dark and clear with clusters in Auriga bright naked eye visible, and I *think* (Checking with Stellarium) I might have glimpsed M33 naked eye, but wouldn't swear to it. Didn't stay out long but was a very happy bunny.

Regarding coinage, skip to the end where he gives reasons why 240 pence to the pound isn't so crazy after all.

Yes, super-pixel mode rings a bell, though I don't have PI. As for the cameras, yes the QHY 410* is 14 bit which may be a problem, but so is the £1000 extra just for a bare QHY 600C. But all this is somewhat academic since it will be well into next year before I can even think of a new camera. *Not to be confused with the QHY 411 which is a whole 'nother ball game and into second mortgage territory.

The QHY 410 makes sense *to me* financially, as the QHY 600 is £1000 more without adding filters or wheel. And I'm not sure about binning colour cameras, I have an idea that it has to be done 3x3?

The thought of *two* ODK 12s on the DDM 85 *is* the stuff of nightmares, one is quite enough (Or more than enough) though I think the DDM 85 would *just about* carry them.

The Sony IMX 410 has 5.96 micron pixels, so a very similar plate scale. The sensor is used in the Nikon Z6 camera.

16 megapixels. On my ODK that gives a still ridiculous 0.61"/px These crazy high megapixel sensors like the IMX 455 only work if you bin the pixels, which can only be done in software.

I just wish someone would make a BSI CMOS sensor equivalent to the 16200. APS "H" format and 6 micron pixels. Could easily have a FWC greater than 100,000 like the Sony IMX 410.

This is a comparison of FoV on M106 (My current obsession)

The QHY 410C looks to be a good match for my Moravian G3 16200. Use the G3 for Lum and NB, and the QHY for RGB. Haha, upper case 3 is £, so nearly typed G£ 16200 😆. Appropriate really.

This is a possible Super Luminance built from 40 subs Lum, 31 subs Blue, 14 subs Green, and 25 subs Red, only using the clean subs without the light leak. The individual stacks were added before cropping off the alignment edges and given a gradient removal. DDP and Richardson-Lucy deconvolution followed. May have brought the background up a bit too far, some gradients still visible.