gorann

Thanks a lot Mark!

Thanks Dave, much appreciated indeed!

Thanks Andrew! Yes, I have personally been very positively surprised about this relatively inexpensive scope compared to the alternative "astrographs" that often cost a fortune. I think Celestron has really done a good job which has unfortunately suffered from the bad reputation of the Hyperstar concept, which is apparently a very cumbersome add on. I think there are very few similariteis between RASAs and Hyperstars. I have not had to do any collimation even if I bought it second hand.

Thanks a lot Peter for the kind comment!

Here is the third in a triplet of odd looking nebulosity in Cepheus caught with the RASA 8. It is LDN1251 caught last night, and I have recently posted VdB 152 and LDN 1235. The ASI2600MC war as previously run at gain 100 and collected 67 x 5 min before dawn, so 5.6 hours.

Thanks Richard! Yes it is a photogenic nebula. I caught a third one last night: LDN1251. Posting it now. It seems like I am going to get one more clear night🙂 before clouds move in for at least a week🥴

This is quite emarrasing but I just realized that the dark nebulosity to the right in my VdB152 image is part of the Sark Nebula LDN1235 that I just imaged and posted, so tonight I am obviously pointing the RASA towards the last one of this triplet: LDB 1251 seen to the right in this excellent wide field by Scott Rosen:

That is an excellent WF Peter! Love the colours.

Thanks a lot Peter! You are too kind, but I don't mind😉

Thanks Adam! I did the Cave nebula in HaRGB a year ago - a really nice object that has everything.

Thanks Adrian! Yes, it is clearly my favourite camera so far.

Here is VdB152 and surrounding dust structures in Cepheus, caught with the RASA 8 last night. The nebulosity in this area is quite faint, and this is what 5.5 hours at f/2 could collect using the ASI2600 OSC at gain 100. The bird-head like structure to the right is VdB 152 (also known as Cederblad 201), a blue reflection nebula that glows atop of a dark Bok globule called Barnard 175. It is located about 1,400 light years-away from Earth. 82 x 4 min stacked in PI and processed in PS. There is quite a lot of Ha happening in the image so maybe I aim at it again next time the moon is up. There is some annoyingly nice dark nebulosity with some blue reflections protruding from the left edge of the image. Maybe I should crop it away not to distract from the main object? I am tempted to aim at it another night to see it in its full extent.

For my EdgeHD11 I use the mask I cut out from a black plastic sheet to cover my 14" Meade (one hours's work with a box cutter saved me about 50 Euro), and I make a small effort to kind of center it, and it works great. Size does not seem to matter much in this case😉 and I am not sure centering is important either.

Could work, I only managed once, but alternatvely you get a 300 mm lens and do it all over again in three times the time, and then get a 600 mm..... 😉

Thanks Tomato! Sorry if the RASA made the shark fall apart - I also worried about that. But talking about falling apart:

I also the the fish and the rabbit after you told me! I hope your assumption about the Norwegian mountain chain holds true also in our new climate!

@vlaiv please explain to us what offset on CMOS means. I think it has to do with pushing the histogram to the right, but you can probably explain it elegantly.

And then what? - just kidding!😉

That is a truely great looking rendation of our neigbour Dave! I am sure that you all are right in that a well done mosaic with longer FL telescopes would beat a RASA or Epsilon image (and even super expensive Riccardi-Honders), but as noted by tomato, only if pixel peeping. We are all victims of the possibilty of zooming in on images and see how deep they are going. It is like standing in an art gallery with a magnifying glass. Personally I am right now for making images that stand their ground on the distance they should normally be viewed at (which is 30 - 40 cm from a 20 - 30" computer screen). If I want to get really close to a distant galaxy I will use my 2m to 3.5 m FL SCTs, and if I want to capture a big area of nebulosity I use the RASA or even the Samyang 135. Inbetween that it will be my 5 - 6" refractors. I do admire those of us with the patience of doing 10 - 20 (or more) frames mosaics, and those zoomable images are extremey useful for the rest of us to find tagets, but they can only be fully appreciated on a computer where you can zoom in. And for that we have also invaluable tools like Aladin Sky Atlas that is actually giving us a free mosaic of it all.

Hi pass filtering and Noels LCE are both excellent and I sometimes use a little of both. For high pass filtering, I usually use a setting around 90 and then blend the filtered image with blend mode Soft Light to the background (or background copy). I then do a Merge Down. Then to avoid getting bloated stars I use Select -> Color Range and aim the picker for a star. Then expand the selection 1-4 pixels and Invert the whole selection before copying it. That way I get only the structures copied and not bright stars (so a star free selection). Paste that copy as a layer on a duplicate of the image and use the paint bruch to apply where desired.

Excellent result Dave! I would be tempted to increase the contrast in the details a bit (e.g. HiPass filtering), looks like the core at least have more structures to show. But that is me and soft is nice too and your image is certainly very pleasing to the eye.

Lovely shot indeed! I really should put my Samyang 135 more to work. One problem with it, and as Kinch suggested, is that with such a wide field you will finally one day run out of object as it covers such a waste area and almost all good targets are in the Milky way. Of course, at that point of time you could always move to the southern hemisphere😉

Yes, looks great! What camera and scope (Samyang 135?)

Thanks! I did put in LDN1235 in the tags line just below the title.

Thanks Dave! I am sure weather will soon decide to slow me down. First imaging chance this week is Thursday. I actually tried running two rigs on Saturday night but the ASI071 I had on the EdgeHD 11 on the Mesu decided to form ice crystals on the chip, so I was left with the RASA. Looked terrible - I have never seen frost that bad and it was on the chip, not the heated window. I will have to open up the camera and dry the tablets. I read somewhere that the ASI071 is less likely to get frost on the chip if it is cooled down in 5°C steps over an hour. That will slow me down a bit.