Replaced Guide Camera, and Took a Step Back

I’ve been frustrated with my guiding performance for some time, getting elongated stars and soft contrast, and decided to slow down ad tackle this.

I replaced the guide camera with a Lodestar which mounts rigidly to the main camera’s guide port using a threaded C-mount. There is no flexure at all in this arrangement, and the Lodestar’s sensitivity produces better guide stars.

I also switched to guiding with separate guide software (PHD) since I was worried about an effect when guiding with Maxim: it doesn’t use a separate process for the guiding action, so during the QSI583 camera’s long download time (30 seconds for a large 1×1 image), Maxim is blocked and not guiding.

This arrangement seems to work well, and I’m getting good round stars in 5- and 10-minute images.

M57-Lum-2011-06-18To test this I started a new M27 project. For this project, I also decided to follow some other good advice I’ve read and heard: slow down and stop trying to capture a complete image in one session.

First night I captured just an hour of unbinned Luminance in 5-minute subs, and an hour of Hydrogen-Alpha in 10-minute subs, that I’ll use later. I focused each separately and captured flats immediately after each session so the flats were captured with the relevant filters in exactly the same position (and thus much more effective at removing dust donuts).

On a second clear evening I was able to collect an hour of Green 2×2. I haven’t collected Blue or Red yet. However, I must say I’m very satisfied with the L, G, Ha frames so far. Patience will pay off.

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