Wednesday, May 28, 2014

The QHY5L-II Planetary and Guide Camera

I recently purchased a QHY5L-II monochrome camera from AstroFactors of Plano, Texas. Bruce was a pleasure to deal with and he keeps a full stock of the QHY cameras and accessories.

The main reason I bought this camera was to replace the Orion StarShoot Autoguider (SSAG) as my primary guide camera for long exposure astrophotography. The chip in the QHY5L-II is a bit smaller than the one in the SSAG so I was a bit worried that it would not be the right choice for me, especially since I would like to someday go to an off-axis guider (OAG). The field of view would be much less shooting through an OAG compared to my current setup of guiding through the Orion 50mm finder/guider. However, so far I have been extremely pleased with this little camera....and I do mean little. Here is a shot of the camera next to an old Orion Explorer II 25mm 1.25" eyepiece.

Shown here with the focal ring from the Orion SSAG.

One of the big reasons I decided to go ahead and buy this camera is the high quantum efficiency (QE) rating. With the outstanding QE of 74% I am seeing many more stars compared to the old SSAG. With a chip this sensitive, I should have no problems finding a star to guide on when I make the move to an OAG.

My current method of guiding for long exposure astrophotography using the Orion 50mm finder/guider. Camera is inserted into the Orion extension tube and focal ring is set to easily return to focus. Also pictured is the ADM Vixen dovetail, v-clamps, and rings.
Another reason for making this purchase is that its an outstanding planetary camera. This camera, along with the ZWO ASI120MM (mono) and 120MC (color), seem to have taken over the planetary and solar system imaging forums as of late. These cameras use the same 1/3" Aptina MT9M034 CMOS sensor which has 1.2 million very small 3.75 micron pixels in a 1280 X 960 array for very high resolution imaging. The camera excels on planets, as well as lunar and solar imaging, with its high frame rate of 30 fps at full resolution. It is also capable of up to 200 fps at lower resolution. With my limited abilities with planetary imaging it will be a long time before I'll outgrow this camera. I think there might be better cameras out there, but you'd be hard pressed to find a better value. Before looking at my first attempts at planetary imaging with this camera, please take a look at this link to see what it is capable of in the hands of a more experienced user. Some have even used it for deep sky imaging of small planetary nebula! http://qhyccd.com/en/left/page3/qhy5-ii-series/

My first night using this camera was as an autoguider. It performed as expected and I was able to collect 4.8 hours of LRGB data on the Iris nebula (NGC 7023). I decided to do this with the 80mm apo at f/4.8 for a wide field shot. Main imaging camera was my SBIG STF-8300M and filters were the Astrodon Gen 2 E-series LRGB. I tried this target three different times last year with my DSLR but the heat was too much for the uncooled sensor to overcome. It turned out with fairly low noise levels this time with the new camera set to -15*C.



Since this image of the Iris nebula the weather here has been awful for astronomy. There have been a few nights though with party cloudy skies. The nice thing about planetary imaging is you can shoot about 1500 frames in about 1 minute. This, I thought, would be a perfect time to try my hand at planetary imaging!

QHY5L-II in the C8. Not shown in this picture is the 2X barlow lens that works well for solar system imaging with this setup.
For these images I used Registax 6 and had it use the best 500 frames. Jupiter and Mars were done with a 10" Meade SCT at f/10. A few nights later Saturn was done using a Celestron 8" SCT at f/20 with a 2X barlow.






Yes, more practice is needed. But it is a lot of fun and these were all done with about 1 minute each of sky time. ZWO sells a 1.25" LRGB filter set ($88) and a 5 position manual filter wheel ($88). I will likely get these to have for planetary imaging since I'd rather not take my SBIG camera off of my Starlight Xpress filter wheel. The Astrodon filters are quite expensive and I just dont want to take any chances of getting dust on them. I might even try using the QHY some evening to image some of the small planetary nebula since the Orion SSAG still works and can be used to guide.

I am hoping the clouds will part soon so I'll be able to get back to my true passion of deep sky imaging. But it sure is nice to have options, even on those mostly cloudy nights! :)