Recommended Canon DSLR for astrophotography?

[jman17]

Hi,

I am considering buying a new Canon DSLR for astrophotography as I want to tether my camera to a laptop and can't do that with my current DSLR. I am doing fixed tripod astrophotography at the moment but want to buy a good DSLR for astrophotography through a scope too and daytime photography. My budget would be up to about $1000 or so and I want to get one that is a step or two up in quality from the Nikon D3100 that I am using now. Can anyone recommend a suitable Canon DSLR for me? As I said I plan to use tethering software to tether to a laptop so I need one compatible with some good software like Backyard EOS. I read that the Canon EOS 750D is a recommended camera for astrophotography and I can get it with an 18-55mm IS STM kit lens for around $1000. Would this be a good choice? Any camera I buy would need the exposure bracketing function for HDR photography as well. Any advice is appreciated.

jman17

[bojan]

Second-hand 450D.... it is easy to modify.

[JA]

Hi Jman,

There is a free software program called Digicamcontrol, that provides tethered control of various cameras, including many Nikon cameras. The program says it provides tethered control of the D3100, but unfortunately no live view or Bulb mode. If you had the D3200 or 3300 you would be OK in those respects.

Anyway, for what it's worth, you could try tethered control of your D3100 within certain shutter speed parameters (Probably only those on the camera) to get a feel for things, without spending a cent. The no live view via the software view is a downer though and no different as I understand to that provided (or should I say not provided) by Nikon's own capture software (Capture or Capture 2 I think they're called).

EDIT: You can get a D3200 or D3300 in the $200-300 range 2nd hand, if you look about. Much easier. See digicamcontrol supported cameras list: http://digicamcontrol.com/cameras

Best
JA

[casstony]

The Nikon d5300, d5500 and d5600 reputedly have very low noise Sony chips while Canon cameras have traditionally been quite noisy. Apparently Canon dramatically improved dark current with the 7d MkII and I imagine similar technology has been used in some other late model Canons but I haven't seen data for other models.

I've got a noisy Canon 600D and have been considering switching to Nikon.

[Nebulous (Chris)]

Originally Posted by casstony

Apparently Canon dramatically improved dark current with the 7d MkII and I imagine similar technology has been used in some other late model Canons but I haven't seen data for other models.

I've got a noisy Canon 600D and have been considering switching to Nikon.

I mostly use a Canon 600D too, and I agree it's not the best at higher ISO. I've also got a 7D Mk2 that I mostly use for photographing wildlife, and that's much better. The old 7Ds were not as good so they smartened the act up a lot with the Mk2. But it's quite a heavy lump to stick on the end of a telescope, especially if the focus mechanism is a fairly crude friction drive.

I only have "Happy Snap" requirements for my shots, just as personal records of areas of sky that I've visited, so the old 600D mostly does OK for me at 800 or 1600 ISO. And it's light and... well... whisper this quietly... but it wouldn't be such an expensive tragedy if I dropped it in the dark...

I believe that the 6D mark2 is due to be announced sometimes this year so I've been keeping an eye on the price of the 6D Mk1 bodies. There might just be good prices to be had there once the rush for the new one starts??

[casstony]

Originally Posted by Nebulous

I believe that the 6D mark2 is due to be announced sometimes this year so I've been keeping an eye on the price of the 6D Mk1 bodies. There might just be good prices to be had there once the rush for the new one starts??

While the 6D has a good reputation it still has very high dark current and the current Nikon D750 is much less noisy and it has a flip out screen.

[DarkKnight (Kev)]

I'm going through the same process and have decided on a pre-loved Nikon D600/D610 which you should get for your budget. The extra real estate offered by the full frame Sony sensor, which it shares with the D750, is a huge plus for wide-field shots, particularly of the Milky Way.

My thinking is that the bigger pixel size of the full frame sensor offers much higher light grabbing ability than the smaller pixels on the cropped sensor, and that is what this genre is all about, gathering dim light.

In a different scenario, like shooting birds in good light, the higher pixel density of the crop sensor may offer more detail.

Have a look here http://www.digicamdb.com/compare/can...vs-nikon_d600/ for a detailed comparison on the two camera's sensors.

Good luck with your deliberations.

[jman17]

Hi,

Thanks for the info. I was going to buy a Canon DSLR as I read that they have many more options for astrophotography software but hearing about them having problems with noise has made me consider other options. If I was to buy a Nikon D5500 would it be a problem finding good guiding software and so on to use with it, as I hope to use it through a scope too in the future? Would it be too limited in this way? It is compatible with digicamControl for the tethering but I don't know much about guiding software etc for AP through a scope and want to be sure before I buy a camera. I do have a Nikkor 18-55mm kit lens from my Nikon D3100 which if compatible with a Nikon D5500 could save on cost too.

jman17

[bojan]

In terms of noise Canon is THAT much worse than Nikon to be a problem... and noise is easily removed with stacking anyway (using DSS for example).

Guiding is not the issue here, as it is done with separate (usually webcam or dedicated guiding system) camera anyway.

Second-hand 450D can be found on ebay for $200... worth considering for a novice.

[JA]

Hi Jman,
Your 18-55mm is also compatible with the Nikon D600 which whilst a Full frame camera, will also operate in DX mode by cropping the sensor and thereby not vignetting the image. The D600 or D610 would be excellent choices and exceed the performance of the D3100-3330 , D5XXX series and the Canon 6D. They would offer a 1-2 stop improvement in dynamic range and/or reduced noise at equivalent ISO sensitivity.

Best
JA

[DarkKnight (Kev)]

I tried 3 or 4 Tethering programs and found this one by far the best.

https://www.controlmynikon.com/download

[casstony]

Originally Posted by bojan

In terms of noise Canon is THAT much worse than Nikon to be a problem... and noise is easily removed with stacking anyway (using DSS for example).

As a processing newbie I'm curious how noise is removed with stacking? When I stack subs from my 600d the noise is amplified along with the signal.

I find it hard to match DSLR darks to lights such that the majority of noise is removed. It would be a lot easier to not have the noise to begin with.

[bojan]

Originally Posted by casstony

As a processing newbie I'm curious how noise is removed with stacking? When I stack subs from my 600d the noise is amplified along with the signal.

I find it hard to match DSLR darks to lights such that the majority of noise is removed. It would be a lot easier to not have the noise to begin with.

Of course the life would be easier without noise.. but it is there (unless M$ are spend for ultra-expensive equipment).
Another way to reduce noise is cooling the sensor.

By stacking frames the random noise is averaged (so, effectively it is removed) .... and subtracting dark frame (stacked from number of dark subs) removes hot pixels and some other permanent artefacts.

[DarkKnight (Kev)]

In case I'm not making my point clear, a pixel on Nikon D600/D610 sensor is approx. 134% bigger than a pixel on Nikon D5500, enabling it to collect more photons. This means that in a given scenario you can use a lower ISO and thus attract less noise.

[bojan]

Theoretically, larger pixel means more photons and less noise, so SNR is better.

Please note, lower ISO will not improve SNR... it just lowers the noise level (and signal level as well).

[casstony]

Originally Posted by DarkKnight

In case I'm not making my point clear, a pixel on Nikon D600/D610 sensor is approx. 134% bigger than a pixel on Nikon D5500, enabling it to collect more photons. This means that in a given scenario you can use a lower ISO and thus attract less noise.

I've been keeping an eye on discussions on cloudynights and found a few websites with interesting info, but it's difficult to find comparison tests of dark current in various DSLRs for long exposures.

One site I found indicates that the D600 is not nearly as good as the D750 for long exposure noise. Assuming the test is fair it might be that the different processors (expeed 3 vs expeed 4) account for the different output from the cameras: https://improvephotography.com/39895...xposure-noise/

[Nebulous (Chris)]

Originally Posted by casstony

While the 6D has a good reputation it still has very high dark current and the current Nikon D750 is much less noisy and it has a flip out screen.

That's good to know. Especially about the flip out screen. I forgot to mention that the flip out screen on my old Canon 600D is a major reason why I prefer it over the much better performing 7D Mk2. I find that tilting the screen up is way easier than trying to crouch low enough to view a flat screen on the back of a camera. In fact at certain angles it's next to impossible (for me anyway).

Of course, that's not really an issue if you have the camera tethered to a laptop and can view and operate it all from there. In my case I only tether occasionally, so the flip screen is important to me. It may be less so for jman17's main way of setting up, but it's still a very good point to bear in mind.

[DarkKnight (Kev)]

Originally Posted by casstony

I've been keeping an eye on discussions on cloudynights and found a few websites with interesting info, but it's difficult to find comparison tests of dark current in various DSLRs for long exposures.

One site I found indicates that the D600 is not nearly as good as the D750 for long exposure noise. Assuming the test is fair it might be that the different processors (expeed 3 vs expeed 4) account for the different output from the cameras: https://improvephotography.com/39895...xposure-noise/

So, with the intention of gathering up some test shots from a handful of different camera brands, I asked several friends, fellow Improve Photography contributors, and Improve Photography readers to grab their cameras and start doing some science to them.

With the tests done by different people and possibly at different locations and times, I wouldn't read too much into them.

Also at ISO3200 some in-camera noise reduction is still performed, even if turned off.

They have the same Sony sensor so I find it hard to accept the huge difference.

I'd be more inclined to believe DXOMark's tests, which show minimal difference, and that is probably due to the D750's later Expeed IV processor.

https://www.dxomark.com/Cameras/Comp...D600___975_834

[casstony]

Unfortunately DXOMark only tells half the story; they don't reflect the noise contribution from dark current in long exposures.

[glend (Glen)]

Teleskop-Express offers a good range of Canon Astro professionally modified cameras here: (scroll down to the Canon section).

http://www.teleskop-express.de/shop/...cessories.html

They are also offering mod services now, where you send them your camera.