Imaging Camera

Digital Single-Lens Reflex cameras allow an entry point to deep sky imaging that wasn’t available 12 years ago. Back then DSLRs had relatively small sensors by today’s standards, terrible noise reduction, and were outrageously expensive. Today’s cameras have big fat chips, exceptionally low noise without cooling and can be had for very cheap! Canon holds the higher share in astrophotography, but there is plenty of support for Nikon as well. Sony and other manufacturers are getting more popular in the hobby, but in my experience, Canon and Nikon still have more software support for camera control than all others combined.

I ended up with a Canon T1i (500D), partly because of compatibility and because of a deal I couldn’t refuse. This was the first purchase I made after deciding to get back into the hobby and I took weeks to decide. I’d always wanted a DSLR for daytime use as well, so I did my research and was careful and patient about it. I stalked ebay for a couple weeks until one jumped out at me. For $150 (buy it now) was a Canon T1i, including an 18-55mm kit lens, 2x16GB SD cards, a charger and battery, all related cables, manuals and even a DSLR specific backpack!  The camera was listed as barely used, and for once it was actually accurate. Everything listed was included, shipping was really fast, and the camera shutter had less than 7,000 actuations. It was essentially a brand-new camera. As a word of caution – be careful with ebay purchases and be ready to be disappointed. I took a chance and got lucky.

For me, the T1i fit the perfect match of price, features and functionality. Aside from the perfect deal I found, they generally sell from $175-$200 with 30,000-40,000 actuations. That sounds like a lot of wear and tear, until you understand that the life expectancy of the shutter is approximately 130,000 actuations.

I prefer to use BackyardEOS (BackyardNikon is also available) for my image capture software. When researching a DSLR to buy be sure that all the functionality you’re expecting to use is available in the imaging software you plan to use. For example, I really wanted live-view, so the lowest model Canon I could get would be the XSi, which is one step down from the T1i. For $20-$30 more on the used market, I could get a better image processor, newer chip and some other small features in the T1i. Those were the deciding factors for me. So, it was a just matter of hunting.

A Quick Note on Astrophotography Specific Cameras over DSLR: 

This is about the entire extent of what you’ll see from me on Astro-specific and CCD imaging at this point. I can see the obvious advantages to these cameras, but I haven’t used them so I can’t really comment in-depth. That said probably the single biggest component upgrade that will improve your images is the camera. While that statement is more observational than through experience, the jump in image quality looks obvious. With the advance in noise reduction on CMOS chips, they are being used in cooled astronomy cameras more and more. The lowest priced astronomy specific camera I would buy if I had the money is the ZWO ASI1600MC – Cool at $1000. The jump to an actual CCD will cost much more, with something like the Atik 11000 on the low end of the cost spectrum for a large format CCD at almost $5,000. With a modified DSLR producing brilliant images and being had for under $400 with some hunting, I think the choice is easy for most beginners. If you’re sticking to it years from now and have reached the limit of what you can achieve, this might be a primary area to look toward.

Guide Camera

Your guide camera has one purpose in life – to lock onto a guide star and not let it go, ever. My initial thought was to use my old Meade DSI with my modified 8×50 finder scope. Just as I was finishing that build, the DSI decided that it no longer wanted that duty. The firmware seemed shot. Windows saw that something was plugged in, but had no idea what. I could still use the modified guide scope, but I needed a camera – another expense that I had to keep it to a minimum.

Guide for a Guide Camera

  • Color doesn’t matter and monochrome may work better for you in light polluted skies
  • You do want fairly large pixels on the sensor – more than 3 microns
  • You don’t need a huge sensor! .25 inch may be pushing it, but .33 inch will definitely do.

The QHY5R-II and ZWO ASI034MC both came in at $100 with very similar specs. The pixels were big enough, as was the sensor, but they were both out of stock… everywhere. When I enquired about the ASI034, I was told that it’s probably not being made anymore due to manufacturing problems and windows compatibility issues. It was then immediately suggested that I get the ASI120MC. Yes, the ASI120 is a better camera to image with, but I wasn’t imaging. All I needed was a point of light to lock onto. I didn’t bite right away, due to an $85 price difference. So, while mulling things over, I found the manufacturing and compatibility claims on the ASI034 to be unfounded, aside from one claim on a message board that was most likely the result of user error I found nothing bad about the model. The QHY camera didn’t come in for months, but the ZWO came back in stock a few days after I was told it wasn’t being made anymore. I snatched it up and received it two days before a long weekend at a dark site!

I have had no issues with the ASI034 aside from what I traced to a bad cable. I can find stars in my red zone skies and not lose them (until they go behind one of the many trees in my neighborhood)! This is one area I think it’s easy to overspend, but there is one exception to spend a little more. If you are planning on doing some planetary imaging, the ZWO ASI120, or QHY-5L would be a good dual-purpose choice to guide and use for planetary imaging rather than buying two separate cameras.