Recent Imaging

I've been imaging over the past few days. The horsehead image from the last post did get its green and blue parts taken:

Flame and Horsehead nebulae

The Moon was Gibbous and nearby; some of its light snuck in and caused the blue-green flare at lower right. This has since been solved by extending the dew shield with some craft foam.

I also had a couple of clear nights during which to image the Rosette nebula. I collectd H-alpha the first night, but it was partly cloudy the second night and I didn't get very many OIII frames.  Consider this a preliminary composite image:

Rosette Nebular (NGC 2244)

The Moon was even brighter and closer to the target than for the previous image, but the dew shield extender worked fine. Next chance I get I will collect more OIII data, and for the first time try to get some SII as well.  I'll get a Hubble Palette image yet!

AT72ED First Light!

Tonight is the first imaging night for the AT72ED (at least for me with this telescope). My target is the area around the horsehead and flame nebula in Orion. A preliminary look at the images is encouraging. I think I may need to adjust the distance between the flattener and the CCD a little. It was H-alpha tonight of course.

The evening has had waves of altocumulus and altostratus move through, so it was fortunate I didn't set up the autoguider. It would have lost its lock several times. Speaking of lost, I wonder how many light frames will have to be rejected because of the clouds.

If tomorrow or Thursday night is clear I'll try a broadband blue filter (perhaps in combination with an Orion astrophotography filter) to pick up the reflection nebulae in the field of view.

Crazy weather for this time of year; the temperature was in the mid 20s with a very light breeze.

Added note: a couple of images taken using the AT72ED are included in the next blog entry.

A blurry cross and noise

Last night I tried to image an Einstein Cross and the Horsehead nebula. The lensing galaxy was imaged, but 20 or so 2-minute exposures were not adequate.  I'm also fairly certain that a 6" telescope is not adequate for resolving this feature.

The horsehead was interesting. It took a lot of time to compose the image. The focuser and extension tube didn't have a good grip on the CCD, so focus drifted a little. Polar alignment was good, as 5" exposures had round stars. There was what I think is some sort of electrical interference coming from (pick one or more) the mount, laptop, or power strip. This resulted in some random noise and narrow horizontal bands. I'll see if I can pin down the source when I shoot dark frames tonight. Tomorrow night is supposed to be clear again, so I'll retry at least the horsehead. I need a target for earlier in the evening, as the HH doesn't clear the trees until several hours after darkness begins.