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View Full Version : Major Problem!!!!



randb
2006-Mar-12, 05:33 AM
I was unable to get the moon into focus..... What could've gone wrong??? Help Please!!!!!!

mickal555
2006-Mar-12, 06:00 AM
Could you give more details?

What type of 'scope?
Has this happened before(have you ever used a scope before?
How were you using it(outside, inside?)
etc...

randb
2006-Mar-12, 06:12 AM
Its a SCT, and I'm a total newbie. I set it up outside, and this is the first time I used this particular one, although I looked through others before.

cjl
2006-Mar-12, 06:39 AM
Did you let it cool down to the ambient temperature before viewing?

Are you sure you were turning the focus knob the right way (sounds stupid, but has happened to me before)?
Was there anything in the way (again - sounds stupid, but I have wondered why I couldn't get the moon into focus before, only to discover that I was looking through a tree)?

If none of those are the problem, then was the seeing just extrordinarily bad (unlikely with the moon however)?

Also, what magnification were you trying to use (what eyepiece)?

Tog
2006-Mar-12, 06:50 AM
Was it cold? Sometimes the heat comming off of your eye will for the eyepiece.

Were you looking over another house or other building? Or a lake or pond? These can cause air currents that may distort your view.

Were you using a barlow? (long tube you put in the scope, then put an EP in the tube? Too much power can overwhelm the scope.

What diameter is the scope? 8 in, 10 in, 12?

If you look in the back of the scope with no EP you should see your own eye surrounded by a bunch of rings. All the rings should be even. Do any look lopsided?

randb
2006-Mar-12, 07:57 AM
I had none of the problems you guys mentioned. I was using an 8" F10 @100x. I just checked the collimation, and it looks perfect!!!

Tog
2006-Mar-12, 08:05 AM
As you focused did it ever get to a point that looked best, then moved past that point? or was it always improving? Or did it never improve?

randb
2006-Mar-12, 08:31 AM
As you focused did it ever get to a point that looked best, then moved past that point? or was it always improving? Or did it never improve?

It never improved.... It looked blurry the whole time...

Tog
2006-Mar-12, 08:36 AM
Check to make sure the focuser knob is tight. There should be a small allen head screw that got in vertically toward the center of the knob. If' it's not tight, the knob will spin without moving the mirror.

It should have made some difference. Totally out of focus, the moon would be a bright haze, and I can get it to that point in my 8" SCT. (Meade).

SarahMc
2006-Mar-12, 01:33 PM
If you could test the collimation ( I assume by focusing a star in/out of focus), you certainly should have been able to focus on the moon.

Most SCT's have a very long focus travel to accomodate accessories in the focal path. It may very well have been (as previously noted) that you were just focusing in the wrong direction. It happens quite often to new users of SCT's or Maks, especially if they've owned refractors previously.

Additionally, the moon is almost full - not the best time to be observing the moon due to it's brightness. Your best lunar views will be along the terminator. Were you using a polarizing filter or other "moon" filter?

Did you try Saturn or Jupiter?

How did you do your collimation test?

naios
2006-Mar-12, 05:37 PM
Wanted to get back to the cool down question - did you leave the scope out long enough to cool down if there was a major discrepancy between the indoor temp and the outdoor one? Out here in the Great White North if I put my scope out and immediately start viewing I would definitely get a blurry moon. Avg temp inside: 68 F, outside 20-25F. I usually need 30-45 minutes before viewing...

randb
2006-Mar-13, 12:09 AM
It was kept outside for 2 hours, so I dont think that was the problem. I didnt try Saturn or Jupiter.

randb
2006-Mar-13, 03:33 PM
I works fine now... Thanks for all your replies. I think Sarah was right...I guess..I was focussing in the wrong direction.