Latest: Artemis Review
The camera is an Art-429. This camera features a peltier cooled 752x582 pixel 1/2 inch ICX429ALL CCD chip with 8.6x8.3 um pixels. This was the biggest chip I've had on my telescope - it might not sound much, but its certainly a step up from the SC3 sized chip. The image on the right shows the camera on my scope. More on those large aluminium plates later.
I've had the camera for a couple of weeks. Of course, its early May, so it hardly gets dark.. and naturally with a new bit of astronomy kit, the weather did not induldge me. I've not been idle. The camera came partly assembled, so I had to finish the job, which involved a small amount of soldering and some thermal managment... but more on that later. I've been trying out the Capture Software, which is simple, easy to use
On the night of 8th May 2005 the moon and the clouds co-operated to leave us a few short hours around midnight to take Artemis for a "spin" around the skies. I did not concern myself with flats and darks and so forth. I wanted to get a feel for the camera under the skies without concentrating fully on producing the best images possible. Visit the equipment page for full details on the telescope and LXD55 mount.
Next I moved a tiny amount to M81. The sky was getting darker so I was able to take longer exposures. So close to the celestial pole, I was able to stack 3 frames of 300 seconds exposure and 2 frames of 150 seconds exposure. A small dust speck is visible upper right. I was quite impressed with this result - especially as it still wasn't dark. The noise in the dimmer regions is caused by the tiny dynamic range between the faint areas and the sky brightness. The image was processed with curves in Photoshop.
Across the sky a little bit more to M94. This galaxy was selected as a test of dynamic range. This galaxy has one of the brightest cores of any galaxy, but the outer region is extremely faint. I stacked 10 images of 180s exposure and usd curves carefully in photoshop to bring up the outer regions.
Over to the other side of the sky to M104, the Sombrero Galaxy. 4 Stacked frames of 60s exposure. M104 was starting to slide down the western sky by now - right in my worst direction for light pollution.
Next I tried a quick spectrum. 30 stacked frames from Beta Leo produced a good spectrum, showing hydrogren absorbtion lines all the way up the Hydrogen Alpha.
Finally I decided to try some colour. This M3 is 10x160s L and 3x60s for RGB. The RGB frames were taken in 2x2 binning. Coregistered in IRIS and multiple L layering with curves in Photoshop.
By this point it was 2.30am and beginning to start getting light. So we called it a night! I'm very pleased with this initial outing. This camera has massive potential. The dynamic range is impressive - my exposure lengths were limited by tracking, not by the camera saturating. You can clearly see some less-than-perfect starshapes caused by tracking errors and something no quite right in the collimation department.
Well done Steve and co. I'll keep trying out this camera for as long as they let me keep it.
