Excelsis - Display Vote

Criterion Dynamax 8

I have bought my dynamax about 15 years ago from a collegue. I had to adjust the secondary mirror (which is a tedious) task. Nevertheless up till now I was reasonable content with it. The motor comes loose from time to time, but that's a matter of fixing the screws tight. The fork is OK. I have made my own equatorial mount on a sturdy demountable wooden structure. Nowadays it seems as if I can't focus the stars for 100% any more. The just out of focus images have dotted stars on several rings which are not perfect cicular. So the diffraction rings are visible only not circular. It wonder whether it is the mirror, the correction plate or the secondary mirror. I hope to find out soon. I am working on a Foucault test, to measure the mirror more detailed. When the tube is exposed to sunlight for longer times (weeks) than some deposit might show-up on the inside of the correction plate. Just cleaning with a little soap and water does the job. There might be some deposit on the two mirrors as well. My former collegue has made beautiful pictures with it. So I think the two mirrors have to be recoated again. The locks on the declination and hour axes have to be readjusted. To much weight on the tube is a slight problem. Then the whole scope becomes a little wobbly. I have a manual, which I intend to put through the scanner, so anyone interested could get a digital copy.
A major draw back is the relative long cooling time of the scope. The longer it stays in the open air the better the images. I do mainly visual observations. and on very cold and clear skies in the Netherlands (which has heavenly light pollution!) I can reach sometimes magnitude 12 - 13. M13 is still a problem I can't resolve the stars, maybe it is also my eyes.

Overall Rating: 5
Weight: 1 (Unreliable Vote)
Date: 08/22/2001 09:16:45 am PST
By: Anonymous (xxx.xxx.117.20)
Link to this vote: http://www.excelsis.com/1.0/displayvote.php?voteid=37932

ga9ZaZ  <a href="http://jlejnshiheky.com/">jlejnshiheky</a>, [url=http://ebclzvozurqw.com/]ebclzvozurqw[/url], [link=http://qcwbhwwjwzap.com/]qcwbhwwjwzap[/link], http://xpeszgtzawdr.com/

>I've had mine for about 3 years and have never had a manual.  I would appreciate it if you could send me a copy of the electronic version to uffda@ns.sympatico.ca

Thanks

Back