ASI183MC Pro or ASI533MC Pro

[Likwid]

Hello Everyone,

Last year, I got an AT72EDII as a secondary scope for more widefield images than my ED80. I have always had this idea that I wanted to have a second more portable rig to work on a large mosaic of the Milky Way while my main rig is on "autopilot", or when I am able to get to darker skies. Now that the Star Adventurer GTi is coming out, I am able to do just that! I am currently imaging with an ASI294MM Pro on my main rig and I just want to have an OSC camera on the AT7EDII simply for the ease of use. I don't want to have to keep changing filters and tweaking focus on multiple rigs throughout the night, and mosaics will be MUCH easier when I don't have to worry about processing all that narrowband data. I am well aware of the amp glow on the 183MC, but I am used to dealing with it on my 294MM so it doesn't bother me. I also know the image quality is not going to be the same with OSC vs. mono so I am not concerned with that. I know there is a lot of discussion on pixel scaling and I have been reading through threads for the last 2 days. I have the 183MC on Backorder but now I am second guessing my choice. I know that the 183MC is better in lower focal lengths than the 533MC, and I would also like to hook it up to my EF 70-200 to experiment with or maybe even put it on the ED80 if I want to get something without having to use R G and B filters, like an eclipse or a comet for example. I really am only between the 183MC and the 533MC based on budget. I like the 183MC because of the price, 20 megapixels, the aspect ratio, and I have seen a lot of good images taken with it. I don't like the 533MC because of the aspect ratio, and it is only 9MP so there is less to work with for cropping etc especially on a square sensor, and it is $100 more. Sorry for the long-winded thread, but I just want to make sure I am making the right choice. Thank you all in advance! 

[Synchronicity]

I've just bought the 183MC for my Esprite 80 for many of the reasons you selected it. Following this to see what others say.

Michael

[Space Oddities]

It's always a difficult choice, with tradeoffs on both side! Have you considered the ASI294MC Pro as well?

I don't own these models, but for what it's worth, here's my 2 cents. I have the bigger brother, the ASI2600MC, and it's basically the same sensor technology and specs as the 533, just in a bigger size. This sensor is truly excellent and produces very clean FITS files.

If I were in your position, I think I would go for the 533. The main advantages I see:

• Newer and better sensor technology
• Bigger pixels
• Higher full well capacity
• 14 bits vs 12 bits
• The resolution is lower than the 183MC, but it's a bit misleading: the 183MC has 3672 pixels in height, the 533MC has 3000. Not a huge difference. The real difference comes from the fact that the sensor on the 533 is square, so most of the lost megapixels are the sides
• A square sensor is indeed uncommon, but I wouldn't see this as a deal breaker. After all, most DSO fit well in a square. If they don't (M31?), you can always do a mosaic: 2 panels with 20% overlap will give you a 14 megapixels image in a very wide ~2:1 format
• If you want to do mosaics, having more resolution could be a disadvantage, due to the larger file size and the additional processing power. It might be overkill as well to have that many pixels... but I agree, it is very cool to zoom in and see lots of details!

The 183 is indeed cheaper, easier to find 2nd hand, has more resolution and could be better for planetary or lunar.

My advice: put both sensor and your scopes in Stellarium, and see what kind of FOV you would get on the main DSO out there. I think that's the best way to see if the format is a deal breaker or not. 

As for the resolution... Well, here's a 6 megapixels image I've taken with my RedCat and ASI178MM. I think that's enough to take a decent picture!

 

[newbie alert]

The 183 has a bigger sensor and smaller pixels so that's where the MP come from... I'd look at bit depth differences to compare 

[Adam J]

4 hours ago, Likwid said:

Hello Everyone,

Last year, I got an AT72EDII as a secondary scope for more widefield images than my ED80. I have always had this idea that I wanted to have a second more portable rig to work on a large mosaic of the Milky Way while my main rig is on "autopilot", or when I am able to get to darker skies. Now that the Star Adventurer GTi is coming out, I am able to do just that! I am currently imaging with an ASI294MM Pro on my main rig and I just want to have an OSC camera on the AT7EDII simply for the ease of use. I don't want to have to keep changing filters and tweaking focus on multiple rigs throughout the night, and mosaics will be MUCH easier when I don't have to worry about processing all that narrowband data. I am well aware of the amp glow on the 183MC, but I am used to dealing with it on my 294MM so it doesn't bother me. I also know the image quality is not going to be the same with OSC vs. mono so I am not concerned with that. I know there is a lot of discussion on pixel scaling and I have been reading through threads for the last 2 days. I have the 183MC on Backorder but now I am second guessing my choice. I know that the 183MC is better in lower focal lengths than the 533MC, and I would also like to hook it up to my EF 70-200 to experiment with or maybe even put it on the ED80 if I want to get something without having to use R G and B filters, like an eclipse or a comet for example. I really am only between the 183MC and the 533MC based on budget. I like the 183MC because of the price, 20 megapixels, the aspect ratio, and I have seen a lot of good images taken with it. I don't like the 533MC because of the aspect ratio, and it is only 9MP so there is less to work with for cropping etc especially on a square sensor, and it is $100 more. Sorry for the long-winded thread, but I just want to make sure I am making the right choice. Thank you all in advance! 

I find if very unlikely that you will get use from the smaller pixels of the 183. The 72mm aperture simply will not support imaging at the resulting pixel scale due to Daws limit, but also due to the likely spot sizes a fast ish ED doublet is able to produce in general. The 533 is a better more sensitive choice as a result. 

Edited August 4, 2022 by Adam J

[SoftwareDeveloper]

I own a ASI183MC Pro, and have had mild regrets. The Bayer filter is not great, all images start out with a blue cast to them, even with the lens cap on. I have wished I had bought the MM version, the resolution however is very nice and I can could have gotten color from RGB filter sets just as I do with my other monochrome cameras. The 183MC is one of my two color cameras and I find I prefer monochrome cameras, for me as a software developer that is not an issue. Your choice should be based on your needs and capabilities.

Color cameras are less sensitive than monochrome, so I have wondered how much better the 183MM would have been at the same images. Too small of a budget to find out!

Sigh.

LIkwid, you will find either camera enjoyable and the slight advantages that one might have over the other in a particular situation is so minor its not worth the fear it causes. I suggest the MM version of either camera, but that is for my style of photography. Pick one and get started! You can have a great time with either one! You will get good experience either way.

:)

[900SL]

I went through the same process and went for the 533 on amp glow, bit depth and well depth

Seriously, calibrating frames is a piece of cake with the 533. Don't underestimate the benefits of the new sensors

And mosaics are the way if you want panorama. I'd vote 533

[Likwid]

Thank you all for the replies! I have actually been messing with dso-browser.com to get an idea of the aspect ratios and differences in apparent focal length between the sensors. I still can't get used to the 1:1 aspect ratio, but they are very close in terms of field of view. Actually, the bigger sensor on the 183MC is almost a good advantage because of the slightly wider field of view. Another big thing to consider for me, is that I generally crop my images to 16x9 to use them as wallpaper. With the 533, I would lose a lot of data and I would have to make sure I framed everything perfectly to allow for that crop, or essentially every image would have to be a mosaic. Seriously, this decision would be so much easier if the 533 didn't have a square sensor. I think I am leaning more towards cancelling the order on the 183 and get the 533 instead. I think the benefits outweigh the drawbacks. Thank you everyone, very much for the replies!

[900SL]

One other thing I forgot to mention about the 533. The square sensor is less prone to edge of field issues arising from tilt, backspacing etc. than a wider rectangular sensor. You are sampling from the center of the circle rather than across the FOV

The smaller sensor also crops the FOV giving a longer reach with your scope

Edited August 4, 2022 by 900SL

[scotty38]

2 hours ago, 900SL said:

One other thing I forgot to mention about the 533. The square sensor is less prone to edge of field issues arising from tilt, backspacing etc. than a wider rectangular sensor. You are sampling from the center of the circle rather than across the FOV

The smaller sensor also crops the FOV giving a longer reach with your scope

So a 533 gives more reach than a 2600 does it? They use the same pixels by the way..... I know you didn't mention a 2600 but this whole reach thing is confusing, to me anyway

Edited August 4, 2022 by scotty38

[900SL]

4 hours ago, scotty38 said:

So a 533 gives more reach than a 2600 does it? They use the same pixels by the way..... I know you didn't mention a 2600 but this whole reach thing is confusing, to me anyway

Technically no, its the same pixel scale. The smaller sensor gives a narrower FOV. You can get exactly the same by cropping the 2600 image to 3000 x 3000 pixel to match the 533 sensor   

[Avocette]

I use the ASI533MC, which I bought in spring 2020, on my ED80 with FR/FF at 510mm. They work very well together with an FoV of 1.25° x 1.25°. When I subsequently bought a 61ED refractor, with its FR/FF at 275mm, for more widefield shots on my second mount, I used my astromodified EOS550D with it for a year. But the wonderful performance of the ASI533MC made me justify to myself buying an ASI2600MC. I began by using it with the 61ED, and the resulting FoV around 5° x 3.25° like with the DSLR, is such a good match, that I have never swapped it over to the ED80.