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What camera is best for long focal length


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Hi, I've got a celestron nexstar 6slt with a 0.63x reducer.

I am currently using a canon 650d on it and am getting some good results, I've recently bought a 72ed with a zwo asi183mc attached to it and like the images you get from it so I've been having a look at what canera would suit my 6slt.

What I would like to know is what cameras a suited to long focal lengths like 1000mm while keeping the pixel ratio in the sweet spot? I've been having a play around on the astro tools website and it seems I need to go for something with big pixel size but I would also like good quality images. Am I better staying with a canon like a 6d or is there a cooled dedicated camera that would suit a long focal length? I can spend 1k on a camera but will struggle to spend more than that.

Thanks for your help

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"I need to go for something with big pixel size but I would also like good quality images."

What do you mean by "good quality" ?

If the pixel size is a good match for the focal length, then resolution won't be a problem.

A dedicated cooled OSC might give less noisy images than say a 6D.

And the OSC may be more sensitive.

I use a modded 6D at 1280mm FL

Michael

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I doubt that sweet spot that you refer to would be hardly recognised on a image on a laptop screen...

Seen plenty of amazing images done with big pixel cameras and short focal lengths and the other way around with long focal lengths and small pixels

I personally use a 8 inch SCT with a reducer, using a 4.54 um camera... Your 650d has a pixel size of 4.3 and relatively small proportion of CMOS sensors have bigger pixels than that..

I'd look at fov of the targets you want to shoot than pixel size

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18 hours ago, labtech1122 said:

I've recently bought a 72ed with a zwo asi183mc attached to it

 

You can always bin 2x2 with the 183 which would technically give you 4.8 um and a resolution of 1.05"/pixel.

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You can always bin your images after taking them to effectively increase the pixel size and signal. Luckily the 183 has tiny pixels and high resolution so even a 2x bin will achieve a decent pixel size. I've found though imaging at 1000mm at f6.3 is rather slow even though the detail is present, comparing it to my f5.9 refractor at around a third of focal length seemed to give a better image (more light concentrated on smaller pixel area).

Edited by Elp
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If I were you, I'd look into the ASI 432MM, 482MC, or 294MM/MC. Of these, only the 294 has a cooled version. The 432MM and 294MM come in monochrome versions, and the 482MC and 294MC are osc cameras. Osc cameras can be deBayered in super pixelmode. The 432 has 9 um pixels, the 482 5.8 um, and the 294 has 4.63 um pixels. Actually, the latter has 2.315 um pixels, but, the osc version has them binned already to 4.63 um size, and the MM version is recommended to be binned. If you go for a non cooled camera (cheaper), a model that doesn't have amp glow is always better. Cameras that have amp glow need matching darks, which is more difficult to achieve with non cooled cameras.

If you want a mono camera, you will also need to invest in a filter wheel, and filters. Any cooled mono camera will break your budget, with maybe one exception. ZWO used to have a cooled version of the ASI174MM, but it is now discontinued. QHY still markets their model, I believe, and so may other manufacturers. Cameras such as the 174 or 482 have pixel sizes that put them in your "sweet spot" at 1000 mm fl.

Both the 174 and 294 have amp glow that needs careful calibration, and I'm not sure if the non cooled versions will work for dso imaging, because of that.

Edited by wimvb
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The 294 uncooled works for DSO as I use one, also a 485 (the newer 585 has no amp glow but these series of cameras have smaller pixels close to the 183). I'd be a bit careful of the 294, calibration or acquisition and application of flats is quite difficult, I don't get such issue with any of my other cameras but I continue to use it as its full well, QE and sensor size is good, the larger pixels make a difference too.

Edited by Elp
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At 1000mm I used an Atik 460 CCD.

Leo Triplet reprocessed. ( Olly Penrice ) - AstroBin

M51 TEC140 data only (ollypenrice) - Full resolution | AstroBin

IC342, a new approach (ollypenrice) - Full resolution | AstroBin

These cameras are no longer fashionable and, therefore, command low prices on the used market. Indeed mine's for sale complete with filterwheel and 6 filters within your budget.

Olly

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I use a ASI178 mono camera (uncooled version £315) with a 1050mm FL Esprit 150 for LRGB imaging of small galaxy and PN targets, binned 2x2 so imaging at 0.94 arcsec per pixel. The sensor does suffer from significant ampglow but this calibrates out with a corresponding dark frame. To achieve a more consistent sensor temperature for this operation, it has been retrofitted with a Peltier cooler, total cost around £40, I’ve never used the camera without this mod, so I can’t comment on how much difference it makes to the data capture.

C821FFF3-13DB-42A8-B1EF-E42986C83BDD.jpeg.413f85935500ded49344f26ef807d2dc.jpeg

TBH, if you want a setup that works right out of the box, and you don’t mind using ‘yesterday’s technology’ I would seriously look at @ollypenrice’s suggestion.

 

 

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