Problems with Lunar viewing with a SW 200p

[Ljblair1]

Hello.

I have been testing my SW200P for a few weeks and I have been unsuccessfully trying to view the moon. It is properly collocates.

When I try and view the moon, it is just a very bright disc. It is not a focussing issue as I have played about with it for hours to get the moon in focus. I can get a very defined disc at what I suppose would be the focal point but absolutely no detail.

Am I just being blinded by the light and if so would a lunar filter bring out the detail I want to see?

Any suggestions would be much appreciated!

Lisa

[Josh Wilson]

Try focusing on a bright star nearby and if you can't get focus then it is a focusing issue. Make sure you use the same eyepiece between the stars and moon. And check the collimation of your telescope too.

[umadog]

If all you get is a very defined disk then it seems unlikely that you're in focus. Remember when checking focus on a star that when you're in focus then star looks like a small point of light. Make sure that turning focus knob is moving the focus draw tube in and out. If the tube isn't moving then the focus isn't changing.

[John]

I think it is a focusing issue. When the moon is in sharp focus it simply abounds with detail, even with much smaller scopes than yours. A blank disk, even though it's sharply defined, is not what you should see at all. Try using your lowest power eyepiece, ie: the 25mm one, and make sure you are not using the 1.25" and 2" eyepiece adapters at the same time - if you are, you won't be able to get an eyepiece to focus.

[Ljblair1]

Ok I tried to focus on a star, but all I got was the mirror target with crosshairs lit up, but no point of light, how can I correct this?

[John]

Thats what an unfocused star looks like through a newtonian scope. My guess is that you have the 2" eyepiece adapter and the 1.25" adapter in the focuser tube at the same time. A very common error with Skywatcher scopes.

[rory]

yep, ive seen this mentioned before. like john suggests, you may have both attachments on the focuser( 1.25" and the 2") which means your eyepiece will be too far away to focus correctly.

or sometimes ( i did this) you need to make sure the focuser locking nut is not preventing the tube moving up and down. theres a good chance one of those will solve the problem.

fingers crossed for you.

[K3ny0n]

Happened to me, I had both the 2" an 1.25" adapter in at the same time.

Big bright white disc with a black dot crosshair visible.

I must of been really excited when setting up the mount and telescope!

Doesn't help with the vague instructions like.

Never mind though it's a easy enough mistake to make.

Rob

[starguest]

Thats what an unfocused star looks like through a newtonian scope. My guess is that you have the 2" eyepiece adapter and the 1.25" adapter in the focuser tube at the same time. A very common error with Skywatcher scopes.

And even the others who mention this.

I'm confused.

The 1.25in adapter goes _into_ the 2in adapter which it is meant to do. The 1.25in is too small in diameter for the focuser. The 2in adapter has a V-shape groove at the ota end which the focuser thumbscrews tighten onto.

[K3ny0n]

The 1.25" adapter should fit straight into the "focusser" without using the 2" adapter.

You basically use one or the other.

Rob.

[moriniboy]

Here is a picture of my 300px focuser, either the 2" or 1.25" adaptor goes in here.

You can tell them beacuse they have a 45 degree flange which is held in place by the 2 screws in the collar.

[John]

The previous two posts are spot on.

If your 1.25" adapter is too small to fit directly into your focuser drawtube, as it should, then it's possible that you have the wrong 1.25" adapter. Did you buy the scope new or used ? - maybe the original 1.25" adapter got lost and has been substituted for another design of adapter ?

[brantuk]

Loads of good focusing advice above.

If once you have it focused the moon is too bright - replace the main tube cap and remove the small offset cap (pop it on the cap shaped bulge opposite for safe keeping). Then point at the moon and re-focus. You'll find it a lot dimmer and easier to look at. Moon views are best when looking at a crescent or half moon. Along the terminator is where you'll see all the interesting stuff cos contrast is good and sharp and not so bright you get blinded.

[starguest]

Ahh, so the standard 1.25in holder has its own 'V' disc that goes into the focuser. Now I'm trying to imagine how it could be attached either above or below the 2in. Bizarre!

[aurochs]

I had a focusing issue with trying to view the moon with my new SW 200P as well. Tonight though I had no such problem (although through the 10mm it was hard to discern a lot of detail, I guess due to the brightness of the near-full moon). I think my issue was merely that I forgot to unlock the focusing lock.

[coulthamst]

The best way to sort out focusing problems is to try to locate daytime objects more the a couple of hundred yards away - being very careful not to turn the telescope anywhere remotely close to the sun - and to practice using the focus control knobs. Once one is able to focus clearly on recognisable daytime objects such as buildings or trees etc, nighttime objects will become easier.

[rwilkey]

Going back to your original post, i think a moon filter would help, an ND96 (0.9) is the best in the 200P in my view, reduces the light intake just right and helps you to see more detail, 13% light transmission here: http://www.ebay.co.uk/itm/1-25-Moon-Filter-Grey-13-transmission-ND96-0-6-/160842044252?pt=UK_Telescope_Filters&hash=item2572eed35c

[JonnyF]

I made the exact same mistake with the 1.25 and 2" adapters on the SW 200p. After being helped by the people on here I got it sorted and have seen some amazing things with it. Takes a lot of time and patience but the rewards are worth it, It took me 2 hours last weekend to find the Andromeda galaxy! Once you get it going you will love it. PS thanks for posting the moon filter advice rwilkey, I was just about to spend £40 on one on first light optics till I saw your post.