Serendipity and a cranky cable

Tonight I thought I'd go back to the Horsehead and redo the H alpha exposures. But when I asked the GoTo to take me there, it instead put me right on the Flame Nebula. I decided to go with the what the mount apparently preferred.

I'm current imaging with my MK-67, an f/12 Mak-Cass. Its focal length is 1800 mm. The ST-8300M's pixel size of 5.4 microns  is about 1/3 the size it should be (about 16 microns for the average poor seeing I get here). I'm therefore binning 3x3 on the camera, which give me about 1.65 arcseconds per pixel. Looking at some of the subs, this seems to work very well.

As I write this I've got 22 subs in for the Flame. Tomorrow night I'll go back (unless the mount has other plans) and shoot some other bands if it holds clear.The odd lines I mentioned last time are gone. I asked on the MAS forum about the noise I was getting the other night. It looks like the best suggestions were about bad or loose cables. Something was acting up tonight when PHD went crazy. The oddest thing was that each exposure caused the PHD window to jump back and forth by about the window frame's width (8 pixels or so). It also couldn't calibrate correctly. Multiple restarts didn't fix this, nor did unplugging the USB cable at the laptop.  However unplugging and reseating the cable at the autoguider did the trick. I begin to suspect that the autoguider's socket is the problem.

The Horsehead image came out okay, but needed more exposures. I think the flame will look much better. I aim to get 30x5min exposures for it.I'll post the Ha images in the next couple of days.

IC 410 image

I have collected OII images for IC 410 and created a composite image.  I think it's only passable. The optical alignment of the CCD and telescope was far from perfect, and I was too lazy to get a good polar alignment. On the other hand, the amount of nebulosity that shows up is more than I expected.

What's neat is that one of the MAS club members who is an advanced imager is going to see what he can do with my narrowband subimages. I bet he can make them look a lot better than the above.

Tonight it's supposed be clear again, and I'm going for a target that's completely different. I'm going to use my 6" Mak-Cass to see if I can image an Einstein Cross. I'll use the luminosity filter for that. No cheating on the polar align for this!

After that, I'll probably target the Horsehead nebula in Orion. The slowness of the Mak-Cass (f/12) will mean long exposures! UPDATE: The stratus deck never moved off, so no imaging. Tonight it's again forecast to be clear.

Next: The Next Telescope? Or camera lenses?

IC 410

Tonight I'm trying to image IC 410, a large emission nebula in Auriga. With no western stars unblocked by the trees, I was unable to get a good alignment. I therefore skipped the polar alignment and moved right to getting light frames using shorter two minute exposures to minimize drift. I also decided to do 2x2 on-camera binning because the nebulosity is so dim. IC 410 is almost round, so composition was easy. Go-To took me to the star field I had noted would be useful for composition, and sure enough the first frame had the target in it just fine. Right now (2300 CST) I've got 40 light frames. I've got the camera running at -35°C for the first time, so I'll need to shoot some dark frames.

I'm only doing H-alpha tonight, and will post a link to the image if it turns out OK.

Now 0200 CST on 12/16/11, and done. 90x2min lights, 30x2 minutes darks, 30x0.04 bias frames. 2x2 binned on camera.

Here's the result; click on the image to see it at 48% of its original size:

Fat stars, but it catches the structure around the central nebulosity. Portions of IC 417 and 405 are in the upper left and right corners, respectively. If it's clear tomorrow night (12/17) I'll shoot some OIII frames and make a color composite.