I was imaging the full moon, using the Lunar1 standard exposure setting (2 seconds).


The moon filled about 1/2 of the FOV and centered, so I'm certain light was
falling on the chip. Perhaps too much light :-)

Also, I actually have the Stiletto knife-edge focuser from www.stellar-international.com
for use with my 216XT, but didn't have time to try it last night. This will
be my obvious next step.

Jeff

>Subject: Re: [M]: Problems with 216XT
>Date: Wed, 03 Oct 2001 07:54:12 -0500
>
>Hi Jeff!
>
>First off, I find the "scotch tape" method Meade recommends to be useless.

>Others may have had success with it, but I did not. A better approach is to

>find an eyepiece with a similar edge-of-barrel-to-glass distance as the
>nosepiece-to-chip distance for your 216 (assuming you are using the
>nosepiece in a 1.25" visual back). It's gotta be pretty close.
>
>The noise you describe sounds about right; this would suggest that the
>scope wasn't precisely aimed at anything - or at least, not precisely
>enough for the image to fall on the chip. The 216's chip is very small, and

>hard to get something right on without a flip mirror (or some such device)

>to help.
>
>The "half-white half-black" phenomenon you describe is something I have
>personally seen. You didn't mention what it was you were trying to image; I

>got this "symptom" when I had a very out of focus, off-center Saturn in my

>FOV. Tweaking the focus helped, and as it came into focus the wide white
>swath became more narrow and eventually disappeared revealing just a blurry

>Saturn (until I finished the focusing). Incidentally, you should always
>focus on a star, and preferably a bright one for a beginner. Just make sure

>to keep your exposure times short enough to not overexpose it.
>
>Chances are, *subtle* focusing is not what you need - you need a lot of
>focal movement. Like I said, my experience with the "scotch tape" a few
>years back was really a fiasco. The scope was nowhere near focus - some
>10-15 turns of the knob off. Don't be afraid to spin in a while in one
>direction or the other. Since this will induce image shift, you'll have to

>be careful to recenter your object (which for a while may mean recentering

>a donut or a white swath...)
>
>Good luck - you'll get there, and believe me, it does get easier...
>
>Mike F
>http://fullerastropix.web.com
>
>
>At 11:49 PM 10/2/2001 -0700, you wrote:
>>I took advantage of a clear night and the full harvest moon to try out my

>>216XT for the first time.
>>
>>I followed the CCD tutorial as described in the manual, using the "scotch

>>tape" method to achieve focus before attaching the CCD.
>>
>>All the images were nothing but noise. Mostly like 50 vertical white lines

>>about a pixel or two across. Sometimes nothing but black, but pressing the

>>left/right arrow keys a couple of times would display solid white on the
>>right 1/2, and solid black on the left 1/2 of the image. Nothing even close

>>to an image.
>>
>>I tried subtle focusing in and out many times, but the images were always

>>pretty much the same noise.
>>
>>I had essentially the same results using MaximDL and PictorView.
>>
>>Any ideas? Just symptoms of poor focusing perhaps?
>>
>>Jeff
>
>
>
>
>
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