gorann

Yes, that explains the confusion. Very odd why it differs between countries since it is not AliExpress that adds the tax, that is done by the courier when it arrives in Sweden.

I got the price from the original post with the link to AliExpress.

The Rising Cam is 1530 USD at AliExpress (your link) and the ASI2600MC is 1799 USD (https://astronomy-imaging-camera.com/product/asi2600mc-pro-color or https://optcorp.com/collections/zwo-sales) so the price difference is not that great in my mind. A major advantage with the ASI camera is the dramatic drop in read noise at gain 100 (where the HCG high gain mode is turned on), so I always use gain 100 on mine. The Rising Cam does not have that feature apparently. It will be interesting to see your experience with the Rising Cam.

The ASI071 was my first CMOS OSC and was a good work horse but when I bought my first ASI2600MC it was clearly a step up. No amp glow, less noise, more sensitive and 16 bit. I sold the 071 this spring to finance another 2600.

Yes, lovely detail indeed Steve. Your mojo has obviously recovered😉

The Bortle 5 may be a problem but a mono will probably only help you if you are going for NB imaging. I have a Bortle 2-3 sky so I hope someone else may advice.

I echo Adam's comment: Why not an ASI2600MC. It is an enormous step up from a DSLR and it would not cost you much more than the ASI1600MM with filters. For RGB I suspect it will beat an ASI1600 with filters (no microlensing, very low noise, no amp glow). And of course you get almost twice as much field of view. You can also use it successfully for NB imaging or dual band imaging (e.g. with a IDAS NBZ filter, like I did in the attached image). I like the 2600MC so much that I now have three of them and I have not used my ASI1600MM for a long time.

Then there is this exciting place to visit in Taiwan: https://www.cloudynights.com/articles/cat/articles/a-visit-to-the-museum-of-astronomical-telescope-r3040

Yes, congratulations to you all! Peter's Cocoon is really amazing so a worthy winner!

Are you sure that more ASI6200MC than ASI2400MC are sold? I suspect that most people that decide to invest that much money in a full frame CMOS will go for mono (= the ASI6200MM) to get more versatility. That is at least what I did, and for OSC CMOS I have gone for the ASI2600 (perfect for RASA 8 for example). The smaller pixel size also gives more versatility since it can be binned. I can for example use my ASI6200MM binned 2x2 (=7.5 µm pixels) or even 3x3 (11 µm pixels) when I hang it on my 14" Meade ACF at 3.5 m focal length, while I use it unbinned on my Esprti 150.

Interesting presentation by Brandon Tackett in that video. As Steve pointed out we have both been surprised how easy it has been to focus the RASA 8 and how well it keeps focus, so maybe there is some QC issues with the focusing mechanism and we have to hope that Olly has baught one without focusing issues. Brandon pointed out that he found the focusing nob very senitive and I have also there the complete opposite experience. I think I have seen that there are micro-focusing nobs that can be fitted to the RASA8 but I never understood why that would be needed. My initial issues have been with sensor distance but I have that pretty much solved now. I now and then get a bit of elongated stars in the corners but that can be fixed in processing and with an APS-C sized camera I cannot complain too much. I had a look at Brandon Tackett's images in Astrobin (https://www.astrobin.com/users/Tackettbr/) and he also seem to have some issues with what could be tilt even if he is using a smaller sensor than me. It could possibly also be that his scope is not as well colimated as he thinks. My second RASA 8 was not perfectly collimated from the box and that gave odd star shapes especially in the corners.

Yes I found it on Amazon or ebay, cannot remeber which one but I remember it was cheap so I bought two which doubles the chance of finding the tool when I need it.

Great! I made two modifications of my Artesky adapter. The most important one was to drill two small shallow holes in it so I can use a tool to unskrew it from the camera since I realized that it could easily get stuck and there is no way to grip it when it is inside the Celestron retention ring. The second modification was to put teflon tape (PTFE tape) on the surface facing the scope. That creates a perfect degree of friction so I can rotate the camera using minor force to help with framing. The tape is only 0.1 mm thick so it will have a minor impact on the sensor distance. About sensor distance: The Artesky adapter comes with a metal distance ring. I use that when I have a filter in the adapter and do not use it when there is no filter. Göran

Not sure what the "Pierro Astro squidge-free adapter plate" is. Does it say "Artesky" on it or has Pierro made his own adapter?

The ASI2600 has virtually the same diameter (90 mm) as the cetral obstruction (93 mm) so running cables along the side of the camera may in itself cause diffraction if they stick out a bit. I have not noticed any diffraction artefacts in the way I have the cables at the back of the camera, so it seems to work fine. Some pessimists have commented on the possibility that the heat from the camera and the fan could cause some turbulence but I have not seen that anyone has shown that this is a real problem that affects the images. In any case I cannot see how it could be avoided since I am quite sure that the corrector plate is too much of a dew magnet to allow the scope to be used without a dew shield.

If it is going to be fully automated then a focus motor is of course necessary, but as mentioned the RASA8 holds focus very well, which is surprising for an f/2 scope, and I never had to refocus during a night. It is very easy to organize the camera cables by taping them to a circular piece of steel wire, and let them out in the slit of an Astrozap dew shield (or similar). A dew heater is not needed - the camera seems to produce enough heat.

Looks great Olly! Nice to see a RASA bathing in sunshine! The first thing you need to remove before you attach a camera is that front glass on the lens assembly.... Never understood why they have it there, maybe just for protection

A Lodestar should be fine or any 1.25" camera. I see that the Lodestar X2 has a CS-thread while the adapter that comes with the scope has a male C-thread, so you need a C to CS adapter. I seem to remeber that I used a Lodestar X2 for my collimation and had to use a C to CS adapter ring. You may have one laying around.

I always have the camera at gain 100 (where the magic drop in read noise occurs). For bright thing like M31 I did a mix of 30s and 120 s exposures. For IFN I have used 5 min exposures and with the dual-band filter I have used 5 to 8 min exposures. I assume you could use shorter expoures but there is a trade off with the amount of data to handle. Stacking can take a an hour or more with these hughe files. Each raw file is 53 Mb, but that becomes 313 Mb after debayer (32 bit as xisf in PI) and 153 Mb as a 16 bit tiff file. So you may find yourself happy that you did not go for a full format CMOS.... Collimation is done on a bright defocused star much like a SCT. There are three pairs (push-pull) of screws on the lens assembly. The main difference compared to a SCT is of course that you need to do it with a camera, and to reach the screws it needs to be a narrow camera, like a Lodestar. The RASA8 comes with two camera adapters, one for M42 and one for a C-mount camera, so for collimation you will use the c-mount adapter and a guide camera of the narrow type. There is some information in the manual (attached). Göran 91073_RASA 8_Telescope_Manual_5Lang_Web Only.pdf

Exciting news Olly! Nice to see that you went for the RASA8 option rather than 11. Should also be easier for the mount to handle. Are you going for an ASI2600MC? I assume you will be thrilled by the results, after you solved any issues with sensor distance and minor tilt. My first RASA8 was perfectly collimated out of the box while my second one needed a bit of collimation, which was easy enough. The very best of luck! Göran

Ps. Olly you will also need to incude the space for a dew shield for a RASA.

Olly, if you aim at buying as used RASA11 make sure you get the new version - the original one had severe issues with the focusing/holding of the primary mirror. I am also not sure what the gain is with a RASA11 with an 24 x 36 sensor compared to a RASA8 with a 24 x 18 sensor. FOV will be about the same. I am setting up a dual RASA8 + ASI2600MC rig to either get immedeate mosaics or RGB + dual band. The cost for my two RASA8 and ASI2600MC was the same as for one RASA 11 and ASI6200MC but I get twice the FOV and more options. The weight is also about the same.

Because I only use OSC (ASI2600MC) with my RASA I use the Artesky adapter so that I can use a 2" IDAS NBX (NBZ) filter for dualband when the moon is out. I did use the Baader system initially and it seemed to work fine, at least with a Baader high-speed Ha filter.

Sorry, I missed the NON🙃

I do not think you should go for an f/2 filter for your Esprit. They are meant for scopes like the RASA 8 and their peak transmission wavelength is shifted to accomodate that very sharp light cone of an f/2 scope. At least ask Baader or FLO about it.