Astrophotography with the Meade ETX-90


Photos and writeup by Trevor Freeman. September 2009.

GETTING STARTED
Canon EOS 20D mounted to Meade ETX90 Telescope My introduction to astrophotography was more of a stroke of good luck than a conscious choice. As it happens, the girlfriend of one of my best friends has an excellent telescope that was just sitting around gathering dust. When the chance to borrow it arose, I jumped at the chance to try it out!

The telescope was a Meade ETX-90, a very respectable entry level telescope. This particular scope came with all of the official Meade accessories including the Deluxe Field Tripod, AutoStar Guide, and the Lunar Planetary Imager. It also had the 26mm Super Plossl eyepiece and a soft carrying case for bringing everything out to the field.

The very first thing I did was order a Meade #64 T-adapter from Amazon and a Zhumell T-ring mount for Canon EOS cameras from telescopes.com. The total for both pieces was $46.95 plus $10 dollars for shipping. You might say I was very optimistic about taking some amazing photos of the solar system. The adapters arrived in a few days and I was ready to get cracking.

The Zhumell ring fit perfectly on my Canon 20D. The ETX-90 has a focal length of 1250mm, which is more impressive than any zoom lens I know about. I already had a remote timer that I purchased on eBay when I first got the camera in 2008. The Aputure DSLR remote timer (awful name, I know!) is a $40 dollar Chinese-made knock off of the real Canon TC-80N3 remote timer. It does the same thing as the Canon timer for about $60 dollars less. Also, it runs on two "AAA" batteries rather than the expensive lithium watch batteries found in the Canon timer.

TRIAL AND ERROR
With all of the equipment in my hands, I was ready to start photographing the night sky - or so I thought! The first few times I tried using the telescope, I did not have any luck getting it aligned. After reading the directions and watching some tutorial videos on the Meade website, I was still not able to get the telescope to align using the AutoStar Guide! Eventually, I gave up on the alignment and decided to use the telescope manually.

Over the next several nights, I experimented with mounting the camera and taking photos. The weight of the camera made it difficult to keep the telescope pointed where I wanted it. To support the camera's weight, I wedged my wallet and cell phone underneath the barrel of the telescope to keep it level. Getting the correct exposure and ISO settings took some trial and error. The slightest vibrations on the ground made the shots come out blurry. It was difficult to focus the shot while peering through the camera's tiny viewfinder.

SUCCESS AT LAST
The Moon! After a lot of bad shots, I turned to the Internet for some tips on photographing the moon. As it turns out, I had completely forgotten about the mirror lockup feature on my camera! Mirror lockup can be enabled as a custom function on the Canon 20D. With that turned on, I suddenly had much better results!

At last I was able to get some decent shots of the moon, properly exposed and in focus! I even managed to get a couple of fuzzy shots of Jupiter from my backyard. For an amateur with no previous experience, I was quite impressed with myself. I used some photo-editing software to bring out the finer details in the shots.

CONCLUSION
My experiences with astrophotography have been hit and miss so far. I've had no luck with the AutoStar Guide, the Meade LPI sensor, telescope alignment, and controlling the telescope with the Meade software via Serial Cable. I also gave up on several "focus assist" programs that download images from your Canon camera to a laptop at high speeds. However, I was able to get some satisfactory shots by just messing around. If you are thinking about getting into astrophotography, my advice is to remain patient and persistent if you want to succeed!

-Trevor Freeman
04 October 2009

THE PICTURES



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