Camera for a Skywatcher dob

[Daf1983]

I have a Skywatcher 200p dobsonian and want some advice regarding the most suitable camera I can buy for it. I have really enjoyed using my smartphone with my dob but I now feel I need something a bit more sophisticated as I move forward. I’m aware that I’m limited to lunar and planetary astrophotography with this kind of mount, but I plan on investing in a equatorial platform in the future when funds allow (if that makes any difference).

I have basically zero experience in photography or astrophotography, so I don’t know much about cameras in general. I have a budget of about £200ish, and so far I’ve narrowed down my options to the following:

1.       Zwo Asi 120MC-S

2.       Zwo Asi 224MC

3.       Canon 550d

4.       Canon 600d

As far as I can see, the main advantage of the DSLR route is that is doesn’t require a laptop to operate, and that you can obviously use it for everyday photography (which I’m not particularly concerned about).

I hope someone can help me with the following questions:

1.       What are advantages/disadvantages of a dslr verses a cheap dedicated astronomy camera?

2.       Would I see a big diiference in quality between the 120MC-S and the 224MC, considering I don't have a tracking mount?

3.       Is there any big difference between the 550d and 600d, apart from the articulated screen?

4.       Are there any better options I have not considered?

Thanks

 

Dafydd

[dannybgoode]

It will be very very difficult to use any camera on a dob mount even just for lunar and planetary work.  A phone shot is just a single quick sub-second exposure whereas when you start using dedicated cameras of any type you will be taking multiple exposures and often for planetary work, video clips of some seconds in length meaning the target is going to pass across the frame and you will forever be having to nudge the mount, wait for the vibrations to settle and take another short clip.  Using a dSLR without laptop control can be fiddly and touching the camera at all will cause a lot of vibrations that will make taking photos without some kind of remote control very difficult.

For me, I would get either of the ZWO's for a couple of reasons (and note I am not hugely familiar with their product range however the spec of the 224 looks to be enough of an improvement to go for that if you can afford it).  1/ They are more suited to planetary and lunar photography than the Canon options and 2/ when you get your EQ mount and you want a camera more suited to do more deep space work you can use the ZWO as a guide camera when you take that step.

That said my advice would be to save the money now and put it toward a good EQ mount and hold off on the camera and enjoy using the phone a bit longer.  If you have a point and shoot camera you could also look at an adapter such as this - https://www.amazon.co.uk/Baader-Microstage-II-Digiscoping-Adapter/dp/B002SYHDIS/ref=sr_1_21?crid=5HUH7AS9HPMJ&dchild=1&keywords=telescope+camera+adapter&qid=1597315133&sprefix=telescope+camera%2Caps%2C143&sr=8-21 - and do some a-focal photography with a slightly better camera than your phone perhaps.

 

[Tommohawk]

Sounds like you've got your head around the key considerations so youre half way there. 

14 hours ago, Daf1983 said:

1.       What are advantages/disadvantages of a dslr verses a cheap dedicated astronomy camera?

Bigger sensor, so much easier to locate your target especially at higher mag eg if using barlow/powermate. This can be quite critical especially if you dont have tracking/goto. As you say also good for non-astro use, but sounds like that's not a priority. Canon 550D is a great camera and has video crop mode for planetary use which works well, but if you want it for astro go for a dedicated astro cam.

If you go for eg a an ASI 120 or 224 you could use that as a guide camera when you get your EQ mount. That said, guide cams are usually mono but a colour cam will work OK if you use it with a guidescope rather than an off-axis guider. Plus of course you can continue to use it as your planetary camera. 

Bear in mind that without coma corrector you will get loss of resolution if your target is off centre, so with the DSLR your bigger sensor is helpful to locate the target but you wouldnt want to image right to the extremes - only the centre (ish)

14 hours ago, Daf1983 said:

2.       Would I see a big diiference in quality between the 120MC-S and the 224MC, considering I don't have a tracking mount?

I have owned a few ASI cameras but not these so cant say. But the 224 does get rave reviews. Not sure how relevent the fact that your mount is non tracking is though - the sensor size is the same. Maybe the 224 has better QE and higher frame rate so you could get more frames before target moves out of shot.

15 hours ago, Daf1983 said:

3.       Is there any big difference between the 550d and 600d, apart from the articulated screen?

You might want to read this. It explains video crop mode and 1:1 video compression issues. The 550D has video crop mode but the 600D doesnt - I never had a 600D so cant speak for any limitations in this regards. But the articulating screen is defintely an advantage!

15 hours ago, Daf1983 said:

4.       Are there any better options I have not considered?

Any number of alternative cameras. I'm experimenting with the 385 which is bigger but more expensive. Main alternative would be to consider mono - of course then you need a filterwheel + filters and processing is more time consuming, although you tend to get a better result. You could then use the mono cam as the guide cam for DSOs and the filterwheel  for you DSO imaging. but maybe thats thinking too far ahead. 

Also consider second hand. I dont think cameras suffer wear as such so possible some bargains out there. 

Good luck and have fun!

[Daf1983]

Thanks for your replies and advice. A lot to think about.

With regards to sensor size on the zwo cameras. I am assuming its a lot smaller than a dslr? Would that mean the field of view would be a lot smaller, and therefore the target would move out of the fov quicker?

 

[Tommohawk]

3 minutes ago, Daf1983 said:

Thanks for your replies and advice. A lot to think about.

With regards to sensor size on the zwo cameras. I am assuming its a lot smaller than a dslr? Would that mean the field of view would be a lot smaller, and therefore the target would move out of the fov quicker?

 

Yup! 550D sensor is 22mm wide approx where 120 is 4.5mm wide. 

[Daf1983]

11 minutes ago, Tommohawk said:

Yup! 550D sensor is 22mm wide approx where 120 is 4.5mm wide. 

Do you think that would be an issue with a manual dob? Does anyone have experience using zwo cameras with a manual dob?

[Nicola Hannah Butterfield]

As @dannybgoodesaid it is probably best to save for the mount first, as any astro photography is tricky at the best of times.

However, that said images can be done with non-driven mounts, when I started earlier this year, I had a Skywatcher 200P on a static HEQ5 mount along with a canon 6D, using a high ISO (sensor sensitivity) of 6,400, I managed to obtain this image of The Orion Nebula.

It is a stack of 80 1/4's exposures, stacked in Registax,  this seemed to take for ever as has been mentioned previously I had to constantly adjust the scope and wait to settle, but not it was an eq mount so a little easier to follow the object as I only really had the one axis to worry about.

I also managed this image of Venus using eye-piece projection, detail are equivalent focal length of the scope was some 18m (yes 18m) @ f/90, shutter speed 1/60th and the ISO 12,800, note this was a single exposure opposed to a video sequence which can then me stacked.

I would imagine, that similar can be achieved with either the 550D or 600D as there was no computer control, the only other thing I had for the Orion shot was an interval timer, so I would frame the scope so as the nebula moved through the f.o.v. I would take several short exposure whilst it was close to the centre of view, then re frame and repeat.

Hope this helps in your decision.

[Daf1983]

1 hour ago, Nicola Hannah Butterfield said:

As @dannybgoodesaid it is probably best to save for the mount first, as any astro photography is tricky at the best of times.

However, that said images can be done with non-driven mounts, when I started earlier this year, I had a Skywatcher 200P on a static HEQ5 mount along with a canon 6D, using a high ISO (sensor sensitivity) of 6,400, I managed to obtain this image of The Orion Nebula.

It is a stack of 80 1/4's exposures, stacked in Registax,  this seemed to take for ever as has been mentioned previously I had to constantly adjust the scope and wait to settle, but not it was an eq mount so a little easier to follow the object as I only really had the one axis to worry about.

I also managed this image of Venus using eye-piece projection, detail are equivalent focal length of the scope was some 18m (yes 18m) @ f/90, shutter speed 1/60th and the ISO 12,800, note this was a single exposure opposed to a video sequence which can then me stacked.

I would imagine, that similar can be achieved with either the 550D or 600D as there was no computer control, the only other thing I had for the Orion shot was an interval timer, so I would frame the scope so as the nebula moved through the f.o.v. I would take several short exposure whilst it was close to the centre of view, then re frame and repeat.

Hope this helps in your decision.

Hello. I've actually brought a second hand canon 600d by now, should be arriving this week.  

I've decided to keep the dob as a purely visual scope, although I might try a bit of lunar photography with it and the 600d, and maybe take videos of planet.

I'm also planning on doing some non-tracking astrophotography with a 600d, a tripod and a intervelometer. I'm not expecting to get amazing results, but am mostly wanting to learn a bit about photography and astrophotography, and see how much I enjoy it, before investing in expensive gear.  If I do find myself really enjoying it, I will probably eventually invest in a star tracker to use with the dslr. 

If I can get anything nearly as good as your picture of Orion, I'll be over the moon👍

[PaulM]

Recently bought a used 350d camera for £30 to see what I could get from my 350p dob and managed this last night of mars 6 best images stacked not processed further. i use a Canon 4524B001 Remote Control RC-06 to take the images quickly after each other

Ive also had to buy a 2x barlow to achieve close up focus as well as a short t-ring adaptor for the camera to achieve primary focus

Edited August 30, 2020 by PaulM

[Daf1983]

17 minutes ago, PaulM said:

Recently bought a used 350d camera for £30 to see what I could get from my 350p dob and managed this last night of mars 6 best images stacked not processed further. i use a Canon 4524B001 Remote Control RC-06 to take the images quickly after each other

Ive also had to buy a 2x barlow to achieve close up focus as well as a short t-ring adaptor for the camera to achieve primary focus

Thanks,  good to know what can be done, I just want to experiment a bit to begin with to see what's possible, I definitely plan on trying this.

I have a barlow already, but need to buy a t-ring and adaptor. Out of interest, where did you get yours? Seems to be a lot of options on ebay/amazon which vary massively in price. I guessing a cheap one would do the job

Edited August 30, 2020 by Daf1983

[PaulM]

this is the t-ring i got

https://www.amazon.co.uk/dp/B0759X99NQ/ref=cm_sw_r_cp_apa_i_G-5sFb4J7HK1Q

[Daf1983]

9 minutes ago, PaulM said:

this is the t-ring i got

https://www.amazon.co.uk/dp/B0759X99NQ/ref=cm_sw_r_cp_apa_i_G-5sFb4J7HK1Q

Great👍 Is that one with a 2inch adaptor?

[PaulM]

3 minutes ago, Daf1983 said:

Great👍 Is that one with a 2inch adaptor?

yep good fit and can get prime focus

Edited August 30, 2020 by PaulM

[Daf1983]

4 minutes ago, PaulM said:

yep good fit and can get prime focus

Would you need a 2 inch barlow lens to use with that? The ones I've seen have t ring which screws directly to the scope for prime focus, and a 1.25 inch adaptor for using with a barlow

(Sorry for all the questions)

[PaulM]

i use a 2" barlow

[Daf1983]

5 minutes ago, PaulM said:

i use a 2" barlow

Aaa, makes sense now. Thanks for the help👍

[PaulM]

51 minutes ago, Daf1983 said:

Aaa, makes sense now. Thanks for the help👍

no worries