[stevous67 (Steve M)]

Okay, I'm bumping back into life an old thread on Metaguide.

Being in this game for a while now I never heard of this program before, but I wish I had! ANYONE WITH AN SCT like scope needs this software!

I confirm that within 30-90mins you'll have your scope precisely collimated. I say 30-90mins depending upon your speed of learning, general computer skills, and I suppose your eye to hand coordination. Once you are familiar with the program, I am sure you could do it within 30mins no problem.

I found the first time I used Metaguide I spent 30-40mins just working out the controls and reading Franks guide, the section on collimation. After that, I proceeded to follow the dancing red dot that shows which way to collimate your scope.

If you look to the link above, you'll find the software to download, and Franks guide PDF on how to use his software. Within his manual, you can jump straight to the collimation section to get going - this is what I did.

I don't want to try to explain how it all works, as Frank's guide does that well. But, to give you a broad overview, you'll be watching three (3) main items to achieve perfect collimation:

1. A main screen showing the bright star being used for the analysis

2. A smaller screen to the lower right that shows a magnified view of that star showing gradients of brightness in varying colours to show the central brightness of the star outwards, indicating coma and distortion. Accompanying this image is a small red dot. You'll be watching this dot's position to make your secondary movements.

3. Lastly, the FWHM measurement for general focus. This you just want to make the smallest possible by adjusting your focus position.

The overall process requires you:

1. to connect a webcam to your scope,
2. Set up your computer screen so you can see the main screen and the smaller screen with the dancing red dot whilst you stand at your scope to make the adjustments.
3. Move the star in the main screen the same direction the red dot is positioned by adjusting your collimation screws.
4. Before making a second adjustment, you must centre the star in the main window again.
5. The goal is to get the red dot stationary in the core of the star (in the lower right window).

As you get the dot central, insert a Barlow to increase magnification, and then start again.

Follow Frank's instructions to make your settings to your video camera.

I have a CDK and never had excellent collimation before, as it was always a little out. Checking my result in CCDIspector, I had zero tilt in X and Y planes, and about 3degrees tilt in the overall image (maybe my CCD).

I am very pleased with Metaguide - Thank you Frank!

Highly recommended!

Steve