We audition a new Rudolph and Frosty makes an appearance.

November 25-26, 2006.

I tried a Meade DSI Pro rather than the webcam as a guider. It should give me guidestars anywhere I need them, which will let me keep the guider and the telescope aligned. And it should play better with the guiding software, too. I'd wait for the USB 2.0 adapter and expect a smoother experience, but the skies for the next few nights look like they'll be too good to let go by without more practice, so we'll see what happens behind the slow connection.

Some software and cabling problems (and some solutions):

(1) I couldn't get the software to connect reliably with and control the DSI. I thought it might be the slow hub, which is notorious for producing problems with the DSI. Or a power issue. Can't address the slow port yet, but I tried it with the powered hub, and saw no improvement. I'm beginning to think that a lot of my guiding troubles, not just these new ones, might be owing to decrepit USB ports. After rebooting and going through the "found new hardware" steps again ("find automatically"), and punching a few buttons I I can no longer remember, the computer recognizes the camera and works just fine for exposures up to 1 second. When I took it outside to try it with the guider and the camera attached to the computer through a hub, problem (2) appeared.

(2) The dreaded white lines. They wreak havoc with finding a guidestar and calibrating. The white lines are a known unknown with a known solution (USB 2.0, maybe avoid the hub with the DSI). This one was described and solved by Tom Nicolaides. Plenty of guide stars appeared even in one second, as promised. It's just that I can't use any of them until the white lines go away. The gracious plenty of guidestars could be even more profound but for problem number 3.

(3) At the beginning of downloads following exposures longer than 1s, the Maxim plugin failed (error -4). Based on the experience of a user on the Maxim group (his limit was 2 seconds), I went around the barn to download the latest Autosuite software from Meade, and that problem went away for me as it did for him. Does this also fix the white lines issue? I'll check that out indoors before making another snake pit of all the wires at the scope. [No, it does not. See photo at right.]

The dark patterns on the CCD were frost: I recreated them inside by simply chilling the chip. Turns out one needs to bake the dessicant every year or so. As this camera has been here for about two years and I'm just finding this out, I'd say it's overdew (sorry). I baked the dessicant plug at 350° for 4 hours, cooled it in a jar I dried out in the oven for the last 15 minutes, and reinstalled it in the camera. Of course I fired it up expecting an instant improvement and then realized that was unrealistic. It'll take 24 hours to purge the imaging chamber of moisture -- see this document from SBIG -- and if it actually needs cleaning rather just drying, see the same document. [20 hours on, a vast improvement. No more worries on this score.]

I infer that I believe all this will work out, because there's a Losmandy DMM plate on its way from Anacortes so that I can use the same ST80 and DSI guider on the Losmandy side by side telescope adapter. Then I can guide the fast 200mm lens on either the Canon or the ST2000 (or whatever else I want to mount on the G11).

 

 

 

Maxim guider control screen showing white lines of death.

 

 

 

Cables, in situ.

 

 

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Text & Photos by David Cortner
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