Adreneline

Hi Peter. I'm not sure I am qualified to comment but maybe this will help: As it happens I have just been imaging M13 with my 6" RC + ASI1600/M6-MkII and this is my equivalent (roughly) plot: I am happy my eccentricity is <0.5 across the plot - my FWHM could be better but the contour looks reasonably distributed about the centre. I know my collimation is not perfect but it is close enough for me. I'll let you draw your own conclusions from the plots for your image. HTH Adrian

Thank you Rodd - I am pleased that you like it. Thanks for the tip - I'll give it a go later and see how I get on - your observations on the image and advice on fixes are much appreciated. Adrian

Thank you. I was surprised just how well the M6 performed considering it was only 15mins and there was a 97% Moon lighting up the heavens! I also captured 7x120s dithered but chose not to use them; I don't think it needs anymore but that a personal taste thing.

With the last throws of astro darkness I decided to have a shot at M13. I have already posted the mono version here but on Friday night it looked like the last chance to add colour so I attached the Canon M6 MkII to the RC and managed to get just 15x60s worth of colour at iso800, guided but not dithered. The colour image was processed separately in PixInsight using the new NoiseXterminator process and the relatively new GeneralisedHyperbolicStretch plugin - just two moderate applications of the latter. I then applied CurvesTransformation too pull out a little more colour taking care not to over-saturate - I just wanted a trace of colour and not a Cecil B DeMille representation as is so often seen. The mono and colour were then combined using LRGBCombination. Thanks for looking. As always C&C are welcome. Adrian P.S. The M6 attached to the RC

I use a Baader UV/IR filter on my ASI120MM-mini with SW EvoGuide and in my experience it has improved the performance compared with no filter fitted. I also use an Astronomik L2 UV/IR filter with my ASI290MM-mini with WO 50mm guide scope on the RedCat 51 - again I think it helps. With either of the above on my SW AZEQ-6 I get ~0.5"-0.8" guiding - with good 'seeing' it's been as low as 0.3".

P.S. I just fitted my Canon M6 MkII to the RC and I am hoping it really does stay clear enough for me to grab 60 mins on M13 again and grab some colour. Fingers crossed!

Hi Steve, I've had a StellaLyra RC6" for a couple of years and almost immediately upgraded the focus unit to a BDST and purchased an AstroEssentials reducer. I was reasonably happy with the results but the star shapes were never that good. Just this week I have 'played' at improving the collimation using a star test and, with reducer fitted, got the best concentric rings patern I could - it wasn't perfect but I couldn't get it any better. I then went on a imaged M13 and was pretty happy with the results. On Thursday night I removed the reducer and imaged M13 again with better results- better focus and better star shapes across the image. I'm not saying I have a perfect collimation but for a £375 OTA I am more than happy with the result. My reducer is staying out and I am going to enjoy 1370mm for a while. Adrian P.S. I did share the results - I guess you've seen this:

Very nice Francki - great detail again and very natural colours. Your TSA120+2600MC are doing a great job. Adrian

Excellent image with great definition and excellent colours. Thank you for including the most interesting NASA link. Adrian

This is a second session on M13 with the reducer removed giving a pixel scale of 0.562 arcsec/pixel and implying an effective focal length of 1390mm. This is four sessions : (25 x 60s) + (25 x 120s) + (25 x 180s) + (25 x 60s) finishing just before transit. I am really happy with the collimation now and don't think any further tinkering will improve things - quite the opposite in fact. I used NINA to collect the data, APP to calibrate, register and integrate and PI to process using two careful and restrained applications of GHS - as little processing as I could get away with. There is no dynamic or automatic background extraction (PI) or light pollution removal (APP) - this is literally how it came out of integration. All I need now is some RGB to bring a bit of colour - later in the year I fear as astro-dark has all but gone. Adrian

Very dramatic Lucas. You've really brought out the depth and structure of this region of nebulosity. Great framing too - that's a really eye-catching central region. Adrian

Thank you Steve - for so little integration time they turned out far better than I expected - truth is I expected nothing - certainly nothing worth sharing.

I decided it was time to bite the bullet and try to improve my 6" RC collimation with a star test; it's still not perfect but it's better than it was! Having stressed myself out I pointed the RC+ASI1600 at M101 (for 50 mins) and M13 (for 30 mins) and this was the result. This is my first GC so I am fairly pleased it worked out reasonably well: I've imaged M101 many times in the past but not at 1100mm - for such a dim target this turned out better than I expected. Due to my own failings calibration has proved to be a challenge but that is sortable with more time. The RC might have a reputation for being 'slow' but it's definitely capable of surprises. Thanks for looking. Adrian

That looks very nice to me. You've managed to keep the core really well defined. The full resolution images shows really good stars all the way to corners with lots of colour. Nice even background too. GC's are the hardest thing to image in my opinion and this one looks excellent to my eyes. Thanks for sharing. Adrian

The extra time has certainly paid off Tristan. The level of detail you've achieved with sympathetic processing is just amazing. A beutiful image. Adrian

Thank you Göran. I think Cepheus is such a rich area to image and so well placed most of the year from this location. My skies are not quite as dark as where you are - I'm more Bortle 4-3 - especially after midlnight when all the street lights round here go off! There are many amazing images from the ASI2600MC revealing a lot of colour and detail. Might have to start saving my pennies! Adrian

I’m amazed the Squid is so clear with just 10 hours of subs; @geeklee and I combined 1600 minutes (over 26 hours) of OIII data last year and it was a real struggle to tease it out of the Bat ( https://www.astrobin.com/ceh9fs/ ). Your combination of Samyang 135, ASI2600MC and IDAS NBZ filter are doing an amazing job when combined with your dark skies. Thanks for sharing. Adrian.

Not sure I've seen an HSS before of this nebula - it reveals a quite different structure to the normal HOO or H(HO)O. Very interesting - thanks for posting.

A wise choice in my experience. The DeNoise can be very helpful, especially when used with a mask, but it can still be a challenge; I rarely go beyond 5-10%.

I really like the framing, field of view and the colour you've achieved with the false SII Tony. Something a little strange seems to be happening at 1:1 in the nebulosity: Could this be to do with Topaz? I use Topaz DeNoise AI and find it quite a challenge to not introduce artefacts especially with sharpening. I also find the DeNoise, although very effective, needs to be used with extreme care. Adrian

I used to get something very similar to this with my Samyang135+ASI1600 mounted on a CEM25-EC - I know this is a different scale in terms of size of scope/mount but the effect was just the same. It turned out that when the flip occured the OTA was moving a very, very small amount because the mounting arrangement I was using at the time was not as tight/firm as I thought it was. I improved the mount of the lens and camera and the problem went away. I was essentially only using a 'central' mount on the Vixen bar which was holding the lens with camera attached. I revised it so I was mounting both the lens and the camera separately on the bar and it stopped the small amount of twist that was happening when the mount flipped. Hope this isn't a red herring!

Haha! Fair enough! To be fair my mosaic was not actually planned - it kind of evolved over a period of time - hence the fact it is not a nice rectangle so favoured by the astro-imaging community. It's all a bit random - like me really CS Adrian

Nice one Göran. Does it count that it's on my Cepheus mega-mosaic? - from May 2020. https://www.astrobin.com/full/uxip1w/0/ I have a plan this year to revisit this region (and the mosaic) and hopefully start to get some OIII and maybe even some SII - who knows?! Adrian

Yes, I use the 11mm ZWO ring but no ZWO EoS adapter. I replaced the EoS lens fitting with an Astrojolo 42mm threaded connection as it is much more rigid and less prone to 'droop'. I have spent what seems like a very long time getting the spacing as close as possible to ideal and I can achieve focus with the foot of the 'L' on the lens when I use my Astronomik Ha, SII and L2 filters. If I use my Baader OIII the focus point moves to about 3mm before the 'L' due to the Baader filters being thicker (2mm as opposed to 1mm for the Astronomik). The spacing is very sensitive - the additon (or removal) of a 0.1mm spacer will have a profound effect on the focus position. HTH Adrian P.S. I use a TS Optics manual filter drawer for 2" filters.

My experience exactly; it wasn't just the fit - the operation was far from easy - frustrating in fact. In the end I decided to buy a second EAF as I too did not want to disrupt my RedCat setup. I did try an old SW DC focuser I had going spare but as I wanted to use the ASIair that was not really a workable solution. Sorry I cannot offer any alternative suggestions. 😐