Which image would be better?

[Mal22]

Hello, 

I have a question that I’m sure plenty of people on here will be able to answer, and explain, with ease… hopefully… 

If I were to take 10 hours of images of M51 with a WO Zenithstar 73 and a ZWO ASI294MC pro, and if I also took 10 hours with the Z73 but with a ZWO ASI585 MC Pro, would the tighter FOV on the 585 result in more “detail” in the galaxy than cropping the 294 image to the same FOV when processing? Assuming conditions were exactly the same for both.

The 294 is obviously the superior camera, but would the tighter FOV on the 585 make it a better option for smaller targets, like galaxies? I already own the 294, by the way, so the point of the question is really whether I’d gain much (for galaxy photography) by adding the 585 to my armoury. 
 

I should clarify in advance that I don’t have enough room currently to store a new longer focal length scope, which I appreciate would be the better solution…

Below is the difference in FOV, and the key specs for each camera. What should I be focusing on to figure out the answer to my questions above?
Thanks for the help! 

ASI294MC Pro Stats 

ASI585 MC Pro stats 

 

Edited June 5 by Mal22

[Elp]

Little to no difference. Smaller camera sensor size does not provide zoom.

The smaller pixels of the 585 will be better for planetary and from my experience the 294 doesn't like fast frame capture so the 585 will also be better in this regard. The 16:9 aspect ratio of the 585 can irk, as you'll soon find you have to mosaic a lot of targets if you don't have access to wider/shorter FL camera lenses.

Also depends on whether your 294MC creates the random red/green swirl pattern effect or not, if it does, any other OSC camera would be better.

Edited June 5 by Elp

[Mal22]

Very helpful thanks! “Smaller camera sensor size does not provide zoom” was what I particularly needed to hear. Very clear. It’ll have to be more focal length. 

I’ve captured a fair few targets with the 294 and I’ve never noticed a red/green swirl pattern, so I’m guessing mine doesn’t, or I just haven’t realised it does! 

[Elp]

To see the pattern you'd have to stretch the image, it's seen even with a mild stretch if you know what to look for. Via an exaggerated histogram preview stretch and after background extraction to remove LP gradients it becomes very clear to see.

With cameras you also have to look at pixel sampling rate, at longer FL you'll be better with a large pixel camera as smaller pixels take longer to saturate if your signal is spread out more across the sensor. There is binning, but personally I haven't really seen the significant effectiveness of it from my projects.

Edited June 5 by Elp

[Fegato]

Hadn't noticed there was an ASI585MC Pro. The ASI585MC is probably mostly used for moon and planetary work, but the cooling turns it into a deep sky camera. It's newer technology than the ASI294MC Pro - so lower read noise, no amp glow (easier to calibrate etc.) in particular. But the ASI294MC Pro has the bigger sensor - and it's a good camera, I still use one with my 8 Edge HD.

As Elp mentions - pixel size is an important factor.  Resolution, or potential resolution, is measured by arc seconds per pixel - this is (pixel size / telescope focal length) x 206.265. 

So with your ZS 73 you get:

ASI294MC Pro - 2.22 arc secs per pixel

ASI585MC Pro - 1.39 arc secs per pixel

So the 585 "can" give you better resolution. But this then depends on how good the seeing is. In the UK you might find that a lot of the time you can't get 1.39" seeing, so the advantage might be somewhat limited.

I don't think either camera is "better" for this set up - often the case in this game! One gives you more resolution, might work better for small targets in particular, and can double as a planetary camera. One still has a good resolution and will provide a larger FOV for larger nebulae, mosaics etc.

[Tony Acorn]

Thanks Fegato - I've just splashed out on the 585MC but the basic version as I'm rather new to this and don't have the time / budget / clear skies to invest in a big AP set-up. I'm pairing this camera with a StellaMyra 80mm ED f/6.25 on a Star Adbventurer 2i wifi Pro and a Manfrotto 055 tripod as a trevlling package but, as the camera and refractor only arrived on Tuesday, I can't say how good it will be. Others may well comment that such a bundle is only as good as the idiot driving it.
Two events I particularly want it to capture are Comet 2023/A3 (Tsuchinshan-ATLAS), for which I'm heading off to The Lizaard in Cornwall in late September and on The Isle Of Wight in October, and 21st August's Lunar Occultation of Saturn.

[Elp]

You'll get excellent results with it. I used the 485MC for long exposure DSO perfectly fine.

[TiffsAndAstro]

8 hours ago, Tony Acorn said:

Thanks Fegato - I've just splashed out on the 585MC but the basic version as I'm rather new to this and don't have the time / budget / clear skies to invest in a big AP set-up. I'm pairing this camera with a StellaMyra 80mm ED f/6.25 on a Star Adbventurer 2i wifi Pro and a Manfrotto 055 tripod as a trevlling package but, as the camera and refractor only arrived on Tuesday, I can't say how good it will be. Others may well comment that such a bundle is only as good as the idiot driving it.
Two events I particularly want it to capture are Comet 2023/A3 (Tsuchinshan-ATLAS), for which I'm heading off to The Lizaard in Cornwall in late September and on The Isle Of Wight in October, and 21st August's Lunar Occultation of Saturn.

I have vaguely similar gear and thinking upgrading my dslr to a imx585 based camera and would love to see your results.

[Elp]

Well, this is my 485 mess around shoot, cam is uncooled:

[Tony Acorn]

1 hour ago, TiffsAndAstro said:

I have vaguely similar gear and thinking upgrading my dslr to a imx585 based camera and would love to see your results.

I can't give you any direct info yet - my package was full of clouds in addition to the expensive stuff. Sadly, I found I was short of a few accessories so ordered them today and they should be here tomorrow - hopefully few if any clouds will be included and then I can get out on Saturday night - it's looking reasonable atm.

[TiffsAndAstro]

14 hours ago, Elp said:

Well, this is my 485 mess around shoot, cam is uncooled:

looks really good to me, especially for a mess around. sadly m31 still not high enough yet for me. 

was looking on svbony's site and noticed 3 days remaining 30 per cent off on

https://www.svbony.com/sv705c-color-planetary-camera-imx585/#F9198J

its not cooled but it seems a really good deal. cuiv the lazy geek did a comparison on noise between same sensor tec cooled and uncooled and he saw a massive difference. via youtube i couldn't see any difference....

if i could quickly sell one of my livers it looks a bargain for £220. probably plus delivery and brexit tax and other things.

 

Edited June 7 by TiffsAndAstro

[Tony Acorn]

5 minutes ago, TiffsAndAstro said:

looks really good to me, especially for a mess around. sadly m31 still not high enough yet for me. 

was looking on svbony's site and noticed 3 days remaining 30 per cent off on

https://www.svbony.com/sv705c-color-planetary-camera-imx585/#F9198J

its not cooled but it seems a really good deal. cuiv the lazy geek did a comparison on noise between same sensor tec cooled and uncooled and he saw a massive difference. via youtube i couldn't see any difference....

if i could quickly sell one of my livers it looks a bargain for £220. probably plus delivery and brexit tax and other things.

 

That looks extremely similar to the ZWO ASi585MC that I've just bought - and a good bit cheaper of course. However, as I use the ASiAir-mini and ASiStudio, I think I'm tied to ZWO stuff - or I have to sell this lot and buy yet more "stuff" which would probably result in my demise. 🤣

[TiffsAndAstro]

4 minutes ago, Tony Acorn said:

That looks extremely similar to the ZWO ASi585MC that I've just bought - and a good bit cheaper of course. However, as I use the ASiAir-mini and ASiStudio, I think I'm tied to ZWO stuff - or I have to sell this lot and buy yet more "stuff" which would probably result in my demise. 🤣

same sensor but not cooled or tec cooled. im sure the ZWO ASi585MC is far better, lower noise due to cooling and probably better software/drivers too. but that costs money

also the zwo lock in which is bad, but, asiair looks extremely user friendly. i have a zwo guide cam and if i didn't like Nina so much i would jump at an asiair and zwo imaging camera.

im new to this hobby so bare that in mind when reading my comments

Edited June 7 by TiffsAndAstro

[Elp]

It might end up costing around 260-270 after VAT+Duties+Handling charge. It's 288 on Amazon ATM.

[Tony Acorn]

17 minutes ago, TiffsAndAstro said:

same sensor but not cooled or tec cooled. im sure the ZWO ASi585MC is far better, lower noise due to cooling and probably better software/drivers too. but that costs money

also the zwo lock in which is bad, but, asiair looks extremely user friendly. i have a zwo guide cam and if i didn't like Nina so much i would jump at an asiair and zwo imaging camera.

im new to this hobby so bare that in mind when reading my comments

I'm new too - just rather long in the tooth (as you may have guessed). For the past few years I've been trying to get better using my traditional cameras and lenses before a bout of The Big C cramped my experiments somewhat but I'm supposed to be clear (although with a few side effects) now so determined to make the most of it for as long as possible.
I went the ZWO route almost on an impulse as I was studying various YouTube content to try to improve and saw several users of that kit together with the Star Adventurer mount I bought. I ought to know by now - more haste, less speed!

[Elp]

Sorry to hear about your circumstances.

A thing I'd like to mention having used all sorts of cameras for astro (other than CCD) is, although the jump to a cooled astro camera does give some gains (sensitivity, lower noise), the first thing I said to myself when I first used a mono cooled from a modded dslr was, "the image is still noisy". Do not expect them to revolutionise your images. They'll improve them of course but from my experience, imaging with a narrowband filter, or better still imaging from a darker bortle zone, far outweighs any benefit changing from a camera body to cooled camera provides. Total imaging time is also significant because the collection of photons hitting pixels is a probability game, fainter signal will activate pixels less, so you HAVE to image for longer, theres no way around this (binning helps but you still have to collect photons over time). It's also similar when you want to reduce noise, the total signal has to outweigh the noise either across the image or within the background sky.

Edited June 7 by Elp

[TiffsAndAstro]

52 minutes ago, Tony Acorn said:

I'm new too - just rather long in the tooth (as you may have guessed). For the past few years I've been trying to get better using my traditional cameras and lenses before a bout of The Big C cramped my experiments somewhat but I'm supposed to be clear (although with a few side effects) now so determined to make the most of it for as long as possible.
I went the ZWO route almost on an impulse as I was studying various YouTube content to try to improve and saw several users of that kit together with the Star Adventurer mount I bought. I ought to know by now - more haste, less speed!

i hope you're doing ok after your treatment. im old too but have been lucky so far. i was very tempted to by the zwo/asiair route but lack of funds made me have to use an old macbook running windows i still wanted to keep my options open so i got a zwo guide camera just in case. im still using a stock dslr, and that is my next upgrade, one day

i have the swsa gti too and while im sure its not the greatest mount in the world, it seems more than capable at least for us noobs. i really dislike the altitude adjustment bolt, it always seems to have a dead spot where it turns freely just as im getting polar alignment bang on. works well with nina though so far.

[Tony Acorn]

7 hours ago, TiffsAndAstro said:

i hope you're doing ok after your treatment. im old too but have been lucky so far. i was very tempted to by the zwo/asiair route but lack of funds made me have to use an old macbook running windows i still wanted to keep my options open so i got a zwo guide camera just in case. im still using a stock dslr, and that is my next upgrade, one day

i have the swsa gti too and while im sure its not the greatest mount in the world, it seems more than capable at least for us noobs. i really dislike the altitude adjustment bolt, it always seems to have a dead spot where it turns freely just as im getting polar alignment bang on. works well with nina though so far.

Regarding your SWSA, I use a pair of slip-jointed water-pump pliers to grip the Altitude knob on my SWSA 2i to extend the adjuster so that a small movement is easier to achieve - if that helps. I wish I had bought your mount rather than going down the cheaper route of the 2i wifi Pro bundle.

All my IT kit revolves around iOS - I've iPads, iPhone and Macs as I didn't buy any new Windows style kit since retiring a decade ago. Although I have a Sony laptop, it can only run Windows 10 and I prefer the security of the iOS system. That limits me to a certain degree as I don't want to put a WIndows partition on any of my Apple kit. I've had a mirrorless Nikon camera for a couple of years now and a Nikon DSLR cropped frame camera before that. I have used the Z6 with a 14mm f/2.8 Samyang and a 70-200mm f2.8 Sigma but the images I got with those - although satisfactory - only made me want to do better.

I finished the temporary build of my portable rig an hour or so back although there is one potentially weak point that needs a better fix - a visit to on-line junk stores should solve that 🤣. I had hoped to get it out tonight but clouds are coming on the wind - WSW - so that invariably means seeing will be poor or impossible here. 

[Elp]

You can make altitude adjustment easier if the scope is loaded onto the mount by shifting the centre of gravity more to the centre of the mount by using a longer dovetail, this highly depends on where/how good your declination balance needs to be.

Edited June 7 by Elp

[TiffsAndAstro]

19 minutes ago, Tony Acorn said:

Regarding your SWSA, I use a pair of slip-jointed water-pump pliers to grip the Altitude knob on my SWSA 2i to extend the adjuster so that a small movement is easier to achieve - if that helps. I wish I had bought your mount rather than going down the cheaper route of the 2i wifi Pro bundle.

All my IT kit revolves around iOS - I've iPads, iPhone and Macs as I didn't buy any new Windows style kit since retiring a decade ago. Although I have a Sony laptop, it can only run Windows 10 and I prefer the security of the iOS system. That limits me to a certain degree as I don't want to put a WIndows partition on any of my Apple kit. I've had a mirrorless Nikon camera for a couple of years now and a Nikon DSLR cropped frame camera before that. I have used the Z6 with a 14mm f/2.8 Samyang and a 70-200mm f2.8 Sigma but the images I got with those - although satisfactory - only made me want to do better.

I finished the temporary build of my portable rig an hour or so back although there is one potentially weak point that needs a better fix - a visit to on-line junk stores should solve that 🤣. I had hoped to get it out tonight but clouds are coming on the wind - WSW - so that invariably means seeing will be poor or impossible here. 

Nah pliers won't help but Ty for the suggestion. The altitude bolt does the job, I can get under 10 arc seconds polar alignment in under 10 minutes, it's just a bit loose feeling, like massive backlash at a certain point. But  my polar alignment doesn't seem to suffer for it.