Top positive review
58 people found this helpful
Dedicated for astro-imaging
on November 14, 2013
I've done a lot of comparisons of imaging cameras and this camera performs extremely well if you use it for it's intended purpose.
I have a 5D II and a 5D III for terrestrial use. While at a friend's observatory, he showed me images taken of M101 with a 60Da. Knowing that a 5D II is _vastly_ better at high ISO (which maintaining low noise) as compared to a 60D (note... I wrote 60D, not 60Da) I expected my 5D II would blow the doors off his image. Boy was I ever wrong. Even doubling and tripling the exposure times couldn't compete. I was convinced and bought my own 60Da.
A 60Da /is/ a 60D with only one difference... the filter. A regular DSLR has filters just in front of the sensor to block UV and IR wavelengths. But the problem with the IR filter is that it's a slow ramp up to block long wavelength light and actually begins blocking the reds well before 600nm (IR doesn't start until about 700nm). Rather than remove the filter entirely, Canon simply uses a much better filter so that the camera blocks very little inside the visible spectrum, but still blocks the IR wavelengths effectively.
The result is a camera which is vastly more sensitive to the reds.
You might wonder why you'd care. It turns out that about 90% of all the atoms in the universe are hydrogen atoms. Hydrogen atoms emit energy following the Ballmer series for Hydrogen wavelengths -- the strongest of which is the hydrogen alpha wavelength at 656.28nm. That wavelength is heavily filtered OUT on a normal camera, but the 60Da allows most of that wavelength to pass unfiltered. This results in MUCH shorter exposures to get the same image and images expose with more intensity -- especially in hydrogen rich nebulae (which turns out to be most nebulae).
Standard astrophotography technique still applies... take lots of frames, learn to stack, etc. etc.
A few other points worth mentioning:
1) The camera includes the AC power adapter. This is important because when doing astro-imaging you'll be taking LOTS of sub-frames and each sub-frame will be fairly long. E.g. you might shoot (just an example) 16-25 "light" frames where each frame is 4 minutes and that's just to image one object. And then of course you'll need about half as many "dark" frames taken at the same settings, exposure times, and camera temperature. Running on battery for this long would kill the battery -- so it's nice that this can run on AC power and you won't have to worry about the battery lasting.
2) The camera includes an adapter for Canon's TC-80N3 Intervalometer. The Intervalometer (not included) has a plug designed to connect to the Canon pro bodies (three pin connector) but the 60Da has a remote trigger jack which resembles a stereo headphone jack. The adapter allows you to use the TC-80N3 with a 60Da.
Canon publishes the camera SDK to remotely control EOS cameras via USB and many astrophotography applications take advantage of this. I noticed that in my astronomy club (a large club with a fairly high percentage of imagers) just about everyone who uses a DSLR (not everyone does) will use a Canon EOS DSLR. I did my own informal software survey and discovered that literally every single image acquisition program I could find supported Canon... only two supported Nikon.
Canon is the only manufacturer to offer a DSLR pre-modified for astro-imaging applications. There are other companies who make CCD imaging cameras for astrophotography (not DSLRs) and many of these have cooling systems to keep noise low, monochrome imaging sensors, and robotic filter wheels (e.g. SBIG, Apogee, Finger Lakes, etc.). This Canon 60Da isn't going to compete with a $10k SBIG camera, but it's a great camera in a nice package and I've seen some stunning images come out of this camera.
BTW, you can use this camera for normal photography, but I don't recommend it. You'll find that the reds are much stronger than you expect. This can be adjusted with white-balance. You would want to invest in a photographic "gray card" and either learn to use "custom white balance" (when shooting JPEG) or get a reference frame of the gray card when shooting RAW. If your primary purpose for wanting a DSLR is for normal terrestrial use, don't get the 60Da... get a camera intended for terrestrial use.