gorann

Oh yes Rodd, you really found som dusty dust there for us to dive into. Excellent processing!

Lovely first image and congratulation to what I know is a fantastic scope! I am surprised that you had to deal with tilt.

Thanks Adam, much appreciated!

Thanks for the suggestions Olly. Did another red adjustment and saturated the blue stars - it did help. I must have stared too long at this data to see clear!

Yes, you are all right. It is over saturated and I was not that pleased myself but there is just such a dominance of the red signal (even if it is only a quater of the pixels on the chip). However, I think I now came up with an easy way to fix it using Selective Color in PS and turning up the blue signal in the red. It also brought out details a bit better. So what about this?

Not sure what SQM you have. Mine is hand held and only have one button. I could give your data a go although I dont think there was anything wrong at all with your processing. Your Epsilon of course win in corrected image circle - 44 mm.

It was excellent Adam, so why not. But how knows what seeing conditions contribute. Did you measure your SQM. I think mine was 21.1 that night (still a bit bright up here).

Yes Adam, I read that too so I expected some edge problems with the 28 mm diagonal of the ASI2600 (even if 32 mm is more than APS-C). However, I found that vignetting is really minimal and no problem, but star shapes are a bit elongated at the edges but I fixed most of that in processing. Since it was not equal in all corners I think it could be related to minor tilt since the tolerances for tilt are extremely small at f/2. Right now I do not feel it is worth the work of trying to deal with it even if the ASI2600 has tilt adjustment. A DSLR is of course not possible at all to use since backfocus is only 29 mm. EDIT: To answer you question, in the second image posted I did not crop and only a minimal crop in the first.

You have some exciting projects to deal with when the sky clears! Good luck again and I am eagerly waiting to see the results.

Honoured to have inspired your purchase! After all it is virtually the fastest wide field scope you can get and I am now doubting that it is behind the Tak Epsilons in image quality, but it is defenitvely well behind in price. And, in my short experience and from what I have read about it, collimation is never an issue with the RASA (spot on from factory) while it is a big issue with the Epsilons. And you do not have to deal with star spikes if you organize your camera cables in a circle. Drawback is that you cannot use a filter wheel but need a filter slider (Baader makes a dedicated one) if you go mono. I would not consider putting it as a third scope on your dual Esprit rig on the Mesu. Sounds extremely complicated and you would rarely want to image the same objects. If you have an NEQ6 class mount lying around, put it on that with a tripod until you build an obsy for it (like I did). If you do not have an extra mount, you may want to invest in one. Maybe even an HEQ5 could swing it. The very best of luck and CS! PS. The Atik Horizon (=ASI1600MC) should be ideal for RASA8's proven image circle, I am pushing it with my ASI2600MC.

This is the first nebulosity that I have aimed at with my new RASA8 and ASI2600MC. Kind of hard to process due to the rich star field. I should get Starnet++ but my OS on the Mac is too old for it. I also shot it before I organized the camera cables in a circle so stars are a bit odd and spiky, but not too bad. I may collect som Ha for it next time it clears. The propeller nebula (also known as Simeis 57) is up in the left corner and kind of obvious. I like the dark nebulosity and globules apparently laying above the Ha structures. I think the dark area down to the right is a big chunk of dark nebulosity and not background sky. 125 x 90 seconds at gain 100 (offset 30). NEQ6 mount. Stacked in PI and mainly processed in PS.

A very good start! A bit noisy still so keep on adding data if weather permits.

I hope my first light made you even more excited Paul. This combo seems like a good match. Good luck with the weather, here it is a bit off right now. Look farward to see your first light!

Thanks, spin it up!

Thanks Sunshine!

Great Lum data Adam! I have with interest compared it to my recent RASA8 image and these two low-f scopes appear to get about equally deep in a similar amount of time. You appear to have no problem with tilt as I seem to have, but then I am pressing it using an APS-C chip. Good luck with grabbing the colour data!

Thanks! Yes, that is what happened to me.... Have a look at what Damien can do with his RASA: https://www.astrobin.com/users/Damien.Cannane/

To see how much dust I can get out of the data I have, I merged the 90 minutes of gain 100 data (used in the previous version) with the 70 minutes of gain 0 I collected the same night, so totally 160 min. I then also did not crop it. Now I think I have caught the full extension of the galaxy dust except a tiny bit at the very left edge. If I frame it carefully and have another go at M31 with the RASA I could get it all in, but then there are so many other interesting objects to aim at..... Still quite happy with how deep I could go with less than 3 hours of data and I found a bit more details in the core.

Thanks! Your scope has about the same focal length as a RASA8 (ca 400 mm) so you would like a camera with small pixels to get a good resolution (arcsecs per pixel). With your scope the ASI2600 would give you 1.85 arcsec/pixel and I do not know if there is an APS-C sized camera with smaller pixels than this one. ASI071 has larger pixels so it would be worse (more undersampling). You can check it with Astronomy Tools on the net. The advantage with the RASA over your scope is that it is faster (collects more photons per unit of time because of the larger aperture) but many would say that f/5.9 is fast enough:

Yes, the ASI2600MC is amazing - virtually no noise (at least I have not felt any need for NR so far) and no amp glow whatsoever (no darks needed). My previous generation CMOS OSC (ASI071) is great but darks were needed and this one is one step up. The one problem is stacking time: each 26 Mpixel file is 50 Mb and with the RASA I get about one such file per minute.....

Thanks a lot Olly! Yes, I think the RASA is quite different from the Hyperstar, and yes I remember your wide and deep M31 image but not many scope/camera combinations include all of M31. Was your image a mosaik? Maybe when it gets darker here I should do a 10 hour run in a night and see how deep I can get with the RASA. Should correspond to 120 hours at f/7 if I rapidly calculated it correctly.

Thanks a lot Richard! I wonder how the RASA compares to Epsilons - it is certainly much cheaper on a price to aperture comparison.

Ha ha! The RASA is imaging near 2 arcsecs/pix so you may beat it at nights with good seeing if you pixel peep. Why not do as I and get a RASA and give it its own obsy. My double Esprits are still in Obsy 1 on the Mesu waiting eagerly for the nights to get longer😃

Thanks! I will check the smudge.

Thanks! Yes, nothing is what it used to be. Olly just posted a OSC image on Astrobin.....