Moon viewing

[Vartigy]

Moon was lovely last night.

Thought I'd try a little up close and personal viewing of the lunar surface.

Anyway, to no avail I couldn't get a clear focused view of the moon.
My rig is as per my signature.
I've got a 10mm and 25mm plossl EP.

I tryed both, zooming to a few times through to both extents.
Then I tryed both with the hard cap (moon filter) on to reduce the light. Still no luck.
Then I tryed both while putting my hand over where the hard cap usually sits, to let in more light but still reduced.
Still nothing but blur.

Anyone got any tips?

[dannat]

I advise to start with the 25mm as it has less magnification & will be easier to focus.

When you move the focuser knob do you see the shaft of it going in & out?

When you tried looking at the moon & were moving the focuser could you see the moon come close to focus then go back out of focus? or was the focus not really changing to your eyes?

Lastly do you know about/how to collimate?

[Tallstock]

Hi anfo,
Can you focus on terrestial objects during the daytime?
Could you view the Moon through the finderscope?
Could you please explain what you mean by "hard cap (moon filter)"?
Where does the "hard cap" fit?

I don't think I got a "moon filter" with my standard SW Flex 8" and I have not had any problems with Moon viewing. I find the 25mm ep result is similar to the finderscope view.
Peter

[Vartigy]

@ Daniel

Yep spent most of time using the 25 for that reason.
Yes that was the first thing I checked, it travels in and out.
When trying to view moon through view finder, couldn't see anything but a white blur. Tryed moving focus as slowly as possible too.
I know about collimating but I don't think it needs collimating. I can focus on just about everything else.

@ Peter
Hi peter.
Yes I can. I lined my finderscope up with my telescope viewfinder on a fire extinguisher on the back of a flatbed truck roughly 600m away.
I can view the moon through the finderscope. Looks amazing through that alone!
Hardcap: On the Skywatcher collapsibles, they have a plastic cover that fits on the top of the tube, on the lower half of the telescope unit. The one with a small circular lid on the hardcap too. I was informed this is like a moonfilter to reduce light.

[bmitchell82]

aaron,

this is what i think has happend . your Secondary is not pointed to the middle of your primary this happend to me on my old blue newt never ever got a clear picture.

My 10" SW although bright as hell, almost blinding although it is crisp and clear so you do not need a apterature block maby you could use a neutral densitiy filter....

Your collimnation is the culprit.

have you got a laser collimnator and a cheshire? this is one of the most effective ways of collmination in my eyes...

Laser to get the depth of your secondary and angle, then the cheshire to get the primary lined up. with this method i can get almost perfect concentric rings with a 20mm and 5x power mate which is up around the 300x mag.

There are not too many truss tube dobs that dont need a good amount of collimnation everytime they are set up due to the movement of the tube. once you get it close you wont need too much fiddling to get it spot on, but if you have just brought it for 100km/s it will be shot! give us a hoy if you need a hand.

oh and to make sure your getting enough movement use some grease proof paper take out the 1.25" adaptor (2 screws on the side) and hold the paper over it, then wind the focuser in and out till you get a nice crisp point on the paper, if you don't get this point theres something wrong with scope the truss tubes arnt long enough

[Vartigy]

just finished doing my first collimation of primary mirror. yeh was out a little bit. noticed that my finder was waaay off too. that might have been partial issue as well.
will give it a crack sat night and let ya know how it went.

[Tallstock]

Aaron,
Remove the "hard cap" altogether. My understanding is that it is only a dust cover.
I do not understand how you could use it as a "moon filter".
Peter

[Blue Skies]

Peter, the hardcap has a smaller hole offset to one side that has a second removable cap. The idea is that you can use this to reduce your aperture for very bright objects, such as the sun and the moon. So instead of using a 20cm aperture you just remove the smaller offset cap and you get 8cm instead. Its a nice size to fit a small sunfilter too, and in theory you can use it to cut down the brightness of a full moon. This is common feature of Skywatcher telescopes, has been for years - even the refractor aperture caps have them. Occasionally we meet newbies who don't realise the full hard cap comes off and have just been using the smaller offset hole and wondering why they can't see much!

[Maxim]

Heh, i thought the small hole was to make it easier to get the large cap off since one of them is pretty tight on my scope. I might give it a try tonight and see what kind of difference it makes.

[Vartigy]

Well I collimated the primary.
Realigned the finder.

Low and behold, tonight, moon was clear as crystal.
With and without the moon filter.

Cheers for the help everyone.

Got some pretty cool shots with a digi camera too.

Spent time cruising Orion Nebula too (i think that's what it's called).

And yes brendon... Astrophotographing will become addictive.

Aaron.

[bmitchell82]

hehehe if your out by a little bit, things just go all fuzzy and double up :) now that you have semi mastered collmination it can only get better from now :)
Congrats on your first step to astroaddiction. and remember there is help for the way ward :D its called star parties :D APA astrop photographers annon :D

[Vartigy]

LOL. Do I have to bring my own booze and support partner?
Rushed home from a job in the bush the other night to get the scope out. Copped my first eyeload of venus just as she fell below the horizon.
Was interesting to see all the heat waves distorting the image too.