Camera advice ZWO 178MM v 585MC

[Davesellars]

Current setup:

EQ5 with RA motor - Using a DSLR with the Canon 70D I've been able to get 1-minute exposures unguided with no real visible trailing using my 80ED and that's not even properly balanced on Dec as the weight of the of the DSLR makes it virtually impossible to balance without putting on a longer dovetail or counterweighting.

I am also planning on starting using the Starfield 102ED on the same mount OTA (tube only) weight difference between the two is approx 1.3kg.  Since the DSLR is around 1.1kg vs a ZWO camera (150g or less), the real difference between the two isn't going to be massive or extra load for the mount and also much easier to balance on the Dec axis (don't have any difficulty with this anyway with the Starfield).

Priorities in imaging:

1. EAA - Although I'm primarily a visual person - there's certain things (well, quite a lot actually) that are out of range in a Bortle 5 sky.  Being able to capture some Ha signal in nebulae and greater detail is great to show my family (with 3 young kids) who are all interested in astronomy, and I've included them in numerous sessions this summer.  For me4., being able to capture better detail on the faint galaxies would also me great and also being able to observe comets and smaller bodies is a bonus.

2. Lunar, Solar (white light) and Planetary...   in that order.  I understand that planetary imaging is probably going to need a longer focal length scope and larger aperture than the 4" but I think it will be sufficient to get some reasonable captures.  Lunar imaging primarily for the doing taking part in some citizen science.

3. Astrophotography - I've come to the realisation that with using my DSLR that I just generally don't have the time for this...  it's just too much of a time sink at the moment and spending hours on the same object is not my thing.  Maybe occasionally though I might setup and have it imaging while I have to do other things during the evening, and I can process later so not discounting AP altogether

Mono / OSC ?  I'm on the fence about this.  I think colour is a nice to have option but probably not at the expense of sensitivity and being able capture much more signal in the same exposure time of the mono camera.  I think the 585 is rather newer though so not sure if the difference between the two is still a lot? or now considerably less...

Cooling not necessary as I'm not doing long exposure AP although I may build a DIY cooler though and have seen an interesting post on using "mobile phone" coolers...

Options:

1.  ZWO ASI 178MM Mono - While the FOV is smaller than the 585 I can almost make up for it with the purchase of the 0.8x reducer for the Starfield.  Without the reducer seems well matched for planetary and lunar especially with the addition of a 1.5 or 2x barlow.   The reducer looks like it would probably work fine with the 80ED as well (i'd get the a M63 to 2" nose adapter so I'm not having to faff about switching between visual and camera usage....)   I don't really need colour but may do some OIII + Ha in the future (with the purchase of a Ha filter).

2. ZWO ASI 585MC Colour - Larger sensor but also quite a bit more expensive.  Hardly any real information about this apart from the numbers look good...  Using a reducer though takes me way over budget so would be working at f/7 instead of f/5.6

So that's my research having looked into various cameras etc and options.  There's possibly a lot I've missed out!   If you've got any suggestions or can recommend either one or the other (or indeed any other option) - particularly interested in the mono vs colour argument especially in relation to EAA use.

 

 

[Elp]

I think if you're looking to do DSO the higher resolution of the 585mc will be better but it's only marginally larger, the larger benefit is the quantum efficiency and zero amp glow of the newer camera.

Mono is more sensitive yes, but I query if you don't have the patience for AP long exp, will you have it for filter changes and image acquisition (are you considering filters?). Filters will usually end up costing more than the camera. You can always use the mono camera as it is in greyscale though a UV/IR filter will cut down on bloated images (just like a luminance filter).

EAVA works exactly like AP taking multiple images but stacking them in real time rather than manually having to do them later so to get a decent image you'll still be exposing for some time. The shortest I ever did was around 10 minutes on the Hercules Globular Cluster (it is a bright target anyway) and around 20 minutes on M101 which started to show the galaxy but in subdued colour saturation.

I think in this respect a colour camera may suit you better. If you want to save some money do what I did and buy a used 485mc which is essentially the same camera as the 585mc but without the amp glow elimination. The 485mc does need a UV/IR cut filter as it only has an AR coated window in front of the sensor, you can image without but the colours will be slightly biased toward red which gives it the advertising spec of an increased IR sensitivity camera.

Edited October 5, 2022 by Elp

[Davesellars]

Many thanks.  I'm not looking directly to use filters although I already have OIII and UHC visual Astronomik filters which I could use on certain targets perhaps and perhaps add a Ha 12nM filter in future...  I'm definitely not looking to do full RGB etc AP - I just don't have the time nor real interest for this; however, I'm really not bothered about colour images for EAA / lunar imaging.  I think most important is getting more data to the sensor quickly.

Edited October 5, 2022 by Davesellars

[Elp]

A mono cam + ha filter will definitely give you the wow factor, even in a single 60-120s image depending on the target.

[Adam J]

3 hours ago, Davesellars said:

Current setup:

EQ5 with RA motor - Using a DSLR with the Canon 70D I've been able to get 1-minute exposures unguided with no real visible trailing using my 80ED and that's not even properly balanced on Dec as the weight of the of the DSLR makes it virtually impossible to balance without putting on a longer dovetail or counterweighting.

I am also planning on starting using the Starfield 102ED on the same mount OTA (tube only) weight difference between the two is approx 1.3kg.  Since the DSLR is around 1.1kg vs a ZWO camera (150g or less), the real difference between the two isn't going to be massive or extra load for the mount and also much easier to balance on the Dec axis (don't have any difficulty with this anyway with the Starfield).

Priorities in imaging:

1. EAA - Although I'm primarily a visual person - there's certain things (well, quite a lot actually) that are out of range in a Bortle 5 sky.  Being able to capture some Ha signal in nebulae and greater detail is great to show my family (with 3 young kids) who are all interested in astronomy, and I've included them in numerous sessions this summer.  For me4., being able to capture better detail on the faint galaxies would also me great and also being able to observe comets and smaller bodies is a bonus.

2. Lunar, Solar (white light) and Planetary...   in that order.  I understand that planetary imaging is probably going to need a longer focal length scope and larger aperture than the 4" but I think it will be sufficient to get some reasonable captures.  Lunar imaging primarily for the doing taking part in some citizen science.

3. Astrophotography - I've come to the realisation that with using my DSLR that I just generally don't have the time for this...  it's just too much of a time sink at the moment and spending hours on the same object is not my thing.  Maybe occasionally though I might setup and have it imaging while I have to do other things during the evening, and I can process later so not discounting AP altogether

Mono / OSC ?  I'm on the fence about this.  I think colour is a nice to have option but probably not at the expense of sensitivity and being able capture much more signal in the same exposure time of the mono camera.  I think the 585 is rather newer though so not sure if the difference between the two is still a lot? or now considerably less...

Cooling not necessary as I'm not doing long exposure AP although I may build a DIY cooler though and have seen an interesting post on using "mobile phone" coolers...

Options:

1.  ZWO ASI 178MM Mono - While the FOV is smaller than the 585 I can almost make up for it with the purchase of the 0.8x reducer for the Starfield.  Without the reducer seems well matched for planetary and lunar especially with the addition of a 1.5 or 2x barlow.   The reducer looks like it would probably work fine with the 80ED as well (i'd get the a M63 to 2" nose adapter so I'm not having to faff about switching between visual and camera usage....)   I don't really need colour but may do some OIII + Ha in the future (with the purchase of a Ha filter).

2. ZWO ASI 585MC Colour - Larger sensor but also quite a bit more expensive.  Hardly any real information about this apart from the numbers look good...  Using a reducer though takes me way over budget so would be working at f/7 instead of f/5.6

So that's my research having looked into various cameras etc and options.  There's possibly a lot I've missed out!   If you've got any suggestions or can recommend either one or the other (or indeed any other option) - particularly interested in the mono vs colour argument especially in relation to EAA use.

 

 

585 it's more about the no amp glow and bigger sensor. If Sony ever release a mono 585 that would be king though. 

[Davesellars]

Many thanks.  I'm wondering if I even need to get the reducer right away and just run with what I have with the 178MM.  I have 3 refractor options and perhaps the 120ST will even work very well with a mono camera and a Ha filter since it's f/5 and has the extra aperture.

[Davesellars]

Ok, so gone for the ASI 178MM.  Sample size seems to be very well matched for the 714mm focal length and also with a barlow in very good seeing for planetary/lunar.  Unfortunately, a much larger mono sensor is a very big price step up - this will certainly do though and is a good enough size for the majority of objects..

Edited October 6, 2022 by Davesellars