gorann

Clearly you got yourself a dream scope Richard! The very best of luck with it and the sky - you seem to be in more luck with the latter than the rest of us. And perfectly collimated out of the box, sounds just like a RASA😉

Ordered the tape from grandado.com but now found it is a Chinese site posing as European so I wonder if and when it will arrive.....

Nice to hear! No I am not talking about the PFTE tape I use as a handy man when I fix the plumbing. There is one with adhesive on one side, like ordinary tape.

Looks very professional! I also worry that an extra 1 mm will affect star shapes. So I searched a bit on the net and there are thinner teflon sheets than 1 mm and there is also thin (0.13 mm) adhesive teflon tape that I am tempted to try.

Good idea Francis! Rotating the camera is a bit cumbersome.

At the end of that news text there is a link to the scientific paper if anyone feels to did deeper into it. I was also struck by the apparent shrinking. Seems to go against physics so it is probably an illusion created by the fading of light.

Just saw this news flash of a dissapearing planetary nebula. Those on the southern hemisphere with big enough scopes better hurry to get their images of it. Amazing that some things in space can change relatively quickly. https://earthsky.org/space/disappearing-stingray-neula-20-years-hubble-images?utm_source=EarthSky+News&utm_campaign=afaf9a5902-EMAIL_CAMPAIGN_2018_02_02_COPY_01&utm_medium=email&utm_term=0_c643945d79-afaf9a5902-394279161

The Artesky holder also wobbles a bit but it does not have the cushions. I realize it will have to have a small enough diamater to get passed the threads of the threaded attachment ring from Celestron, and then a the bottom of that Celestron ring the diameter is bigger and allows the wobbling. My plan now is to put a ring made of garden wire (the one covered by a thin plastic and sold by garden stores for tying up plants) at the bottom of the Celestron ring behind the threads. That should center the adapter and hold it centrally. It works in my inner theatre at least.

I find this thread interesting and also confusing. Apparently Bill's "problem" is that there is a rather small but steady drift between each image, not enough to make the stars elongated, so it is not really a problem. Still it is interesting and I see the same thing from time to time but rarely worry about it. I assume the argument for differential flexure is that gravitation and the movement of the mount slowly pulls the guidescope in one and the same direction during the session (since all movement between subs is in the same direction). Could not also poor polar alignment be the cause, or will that cause field rotation rather than a steady movement? What about a poorly leveled mount? In any case, Olly has a good point about guide scope rings. I never had any and always bolt my guidescope as steady as possible to the main scope (or use OAG when possible, which is on everything except my RASA). Why do they sell those rings?

Thanks! I have the similar Baader UFC slider for my ASI1600MM with the the RASA8, but no filter slider would work for the ASI2600 since the sensor distance is 17.5 mm, and not the generous 6.5 mm we have with the 1600 or 533.

Will your custom adapter be similar to the Artesky adapter or do you have your very own much smarter design?

Yes, it is probably too far from the sensor when you put it in the optical window. I have very little vignetting when I use the Artesky adapter which brings the filter probably 7-8 mm closer to the sensor.

Thanks Adam! Yes, I guess you have been looking at these spectral transmission graphs from Hutech IDAS:

Near the Hamburger galaxy (NGC3628) there are these quasars that are suggested to be between 4 and 10 Giga light years away: http://www.waid-observatory.com/ngc3628-2016-03-31-quasars.html Back in 2017 I could just barely make them out with a 5" refractor and DSLR: https://www.astrobin.com/288366/ I should be able to do that better now, and many of you will probably already have them in your Hamburger images. Here is the image from the Waid Observatory:

Especially in these fuzzy times! Very nice image by the way!

Big it is, or quite close! Thanks a lot Miguel!

Thanks Martin, much appreciated!

Thanks Olly! And here is the full frame one with more data:

Thanks Martin, much appreciated!

Yes, what a useless tilt adapter than cannot be adjusted while imaging - happy I did not need to adjust it since f/7 is so forgiving. I save my troubles to my imaging at f/2 with the RASA8.......

Yes, the ASI6200MM comes with a tilt adapter that is moved from the camera to the front of the image train after you add the EFW and OAG. But I have not needed to adjust it.

Thanks Ken, I was about to ask about the f-ratio😉

Yes, that is the one. I got worried when you wrote "EFW2" which is something different I think.

Are you sure it is the same? The one I have screws on to the camera with a set of small screws after removing the tilt plate on the camera. See here: https://astronomy-imaging-camera.com/tutorials/5-connection-methods-to-get-55mm-back-focus-length.html

I use the dedicated one from ZWO for ASI6200MM for 7 x 2" filters. Supports 7x 2" mounted or 50.4mm (+/- 0.5mm) unmounted filters. The lum in my image was taken through a mounted 2" Baader UV/VIS. FLO will tell you if you can use the EFW2 that you have. https://www.firstlightoptics.com/zwo-accessories/zwo-7x-2-inch-electronic-filter-wheel-efw.html