Alexandre Salvador:
Gabriel R. Santos (grsotnas):
Alexandre, you did not mention a specific budget.
But my recommendation is on an IMX571 camera. Same sensor size as your 800D, but dedicated astro, cooling and better performance (read noise and quantum efficiency, especially, besides allowing full Ha sensitivity). ZWO ASI2600MC is the most popular choice, retails for about 1800-2000USD. You can also get basically the same camera, exact same sensor, on a Touptek (or its rebrandings) for 1200-1500.
If you budget does not allow for the IMX571, you will have to give up some FOV. The next choice would be on a 294-based sensor (or the square 533).
You will also need a way to connect it to your telescope. The camera comes with a 2" adapter, that can attatch directly to the focuser. However, for using a coma corrector, you will need some way to connect it to that. Are you using a coma corrector? If you are having a great time with mounting your Canon EOS and wish to keep compatibility, you can get a EOS-ZWO filter drawer (or simple EOS adapter), that can attatch basically like a Canon DSLR on your existing setup.
Hope it helps, good luck with the acquisition!
Best regards, Gabriel
Thanks Gabriel.
Quick google search returns lots of mentions to the ZWO ASI2600MC Pro. Is that the one you meant , or is there a Pro and a non-Pro?
I'm not using a coma corrector.
My camera connects through a Canon T2 adapter ring, attached to another adapter for 1.25". That goes into where the celestron diagonal used to go. Would the asi2600mc accomodate that without further (€€) accessories?
Sorry, I thought the 127 was a newtonian, that's why I mentioned a coma corrector, but just checked and it is a SCT.
You can use ithe camera directly into the focuser as you are doing (nonetheless a field flattener would be recommended for best edge performance - although I'm not sure there is such a flattener for a smaller SCT as yours).
Yes, the camera I mentioned is the ASI2600MC Pro. I do not think there is a non-Pro version. There is also one that has an integrated guide camera (ASI2600MC Duo) and a monochrome version (ASI2600MM Pro). I'd recommend either MC Pro or MC Duo against the mono. The Duo can be convenient, as you do not need to fiddle with an additional guidescope (probably something for you down the road, with an EQ mount).
I think the 2600 ZWO cameras do not come with a 1.25" adapter (nor a 2"). So you would need an additional adapter, from the camera to your visual back (1.25"). These are relatively simple and cheap parts, but you will have to search for which is the right one.
I have experience with the Touptek ATR3CMOS26000KPA. It features the same sensor of the ASI2600-cameras, but is cheaper. It is rebranded by several manufacturers (Risingcam, Omegon, Lacerta...). My camera came with a 2" and 1.25" adapter, so, for your case, you would not need any additional parts.
I mentioned the EOS adapters in case you were using the camera with a dedicated flattener/reducer/coma corrector, since these typically have 55mm backfocus from a M48 thread. The cameras typically ship with the right adapters for this connection. For you, all that should not be necessary now.
Considering you are using a small scope, with a small 1.25" adapter, you will have quite a lot of vignetting with these APSC cameras. So, if on a budget I'd consider trading off some of the FoV for the cheaper cameras. The ZWO ASI533MC can be had for less than half the price of these other cameras, already comes with a 1.25" adapter (no additional parts), and will image well the center of your scope image circle (with less vignetting and better stars).
Overall I think the IMX571 cameras represent a better long-term investment (once you upgrade your scope). But with your current scope, I think their edges will suffer significantly (but can be used for learning and for capturing some objects). The 533 (or 294) cameras can be cheaper, better utilize your current telescope capabilities, so they are also good cost-effective alternatives (you can search for the great images taken with all these cameras). All options will be more capable than your unmodified 800D in capturing nebulae and overall achieving better Signal to Noise ratio.
