Need help with Skywatcher 200p focusing and lenses

[starryMcStarface]

Hey ?

I took delivery of a Skywatcher 200p last night and got it set up ok I think. I got a good view of Jupiter with the 25mm lens but when I put the Barlow lens in I couldn't focus it.

I also tried the 10mm lens but it made everything grey, no real light comes in at all. It came with a thing that might be called a focuser extension, not sure, but it didn't help.

What rookie mistakes am I making? 

[darknight]

no1 make sure its completely in the centre before using the barlow, as you don't say if you have a tracking mount or not.

there will be no need for extension tubes with the standard eps, so itl be just not used t focus or possibly collimation.

try steps first, like your 25mm, then a 15 or something to gradually home in on it

it could of course be plain old hazy atmosphere but sounds a bit like collimation, a simple Cheshire will do

[Peter Drew]

Collimation shouldn't make that much difference specially as you had a good view with the 25mm eyepiece so I wouldn't worry about that at the moment. You have to put the Barlow lens into the focuser first then the eyepiece into the Barlow before focusing. Try the Barlow and the 25mm first as this will be easier. Probably worth giving it a practice try in daylight on a distant object. 

[Mr niall]

I remember somebody posting a similar problem with a bresser dob recently - I think the moral of the story was something like the 1.25 and 2 inch adapters are stacked together for shipping and they had to remove one or both and fit the little extension tube cos it wasn't reaching focus. 

Now ive read that back I realise that not only have I offered little useful advice but my half remembered story is for a scope that may work differently to yours. Good work me! 

[davehawkins]

Have you taken off the whole of the front lens cover/dust cap and not just the small one that's about 2" in diameter. 

[John]

Hi and welcome to the forum

I don't think collimation will be the issue at this time.

What would really help diagonse the problem would be some photos of the focuser with the configuration of eyepiece / adapter / extension tubes that worked and also the configuation that did not.

Thay way I'm sure we can pinpoint what is causing this quickly.

Could you post a couple of photos ?

Thanks

[Ricochet]

3 hours ago, Mr niall said:

I remember somebody posting a similar problem with a bresser dob recently - I think the moral of the story was something like the 1.25 and 2 inch adapters are stacked together for shipping and they had to remove one or both and fit the little extension tube cos it wasn't reaching focus. 

Now ive read that back I realise that not only have I offered little useful advice but my half remembered story is for a scope that may work differently to yours. Good work me! 

The Skywatcher Dobs tend to come with eyepiece adaptors that have be used separately but are stacked for transport so you can make the mistake of using both when you should only use one. I think when the OP talks of an "extension tube" he's talking about the 2" eyepiece adaptor that shouldn't be used with the 1.25" adaptor. 

With the Bresser the 1.25" adaptor must be used in the 2" clamp but the extension tube is removed for transport and packed with the base rather than the OTA so you can make the mistake of not fixing it to the focuser.

However, I don't think either mistake would allow a 25mm eyepiece to focus and a 10mm not to. 

[JOC]

It's not outside the realms of possibility that, in the time it took you to change EP's, the atmosphere reached dew point and deposited water vapour over all your lens and mirror surfaces.  I have had it happen to me.  It might be you weren't doing anything wrong.

[starryMcStarface]

With the help of the good folk at FLO I figured out what was going on.

@Mr niall was right, I didn't know the 2" adapter was an eyepiece holder, not an extension. I don't need it until/unless I buy a 2" eyepiece.

The problem with the barlow was just me being daft. I gave the cap a gentle tug and it didn't come off so I unscrewed it. That took a part of the lens off  so focus was never going to happen!

Thanks for the help

[JOC]

34 minutes ago, starryMcStarface said:

I don't need it until/unless I buy a 2" eyepiece.

Don't do away with it even if you never buy a 2" Eyepiece.  If your bits are like mine, with a T ring adapter for a DSLR it should mount directly into the 2" focusser mount and this should allow you to get focus with a standard DSLR camera and you might like to take a nice photo of the moon or similar.   Also, if you haven't already discovered it you might find that the 1.25" EP holder unscrews into two parts - the ring obtained is also useful to attaching to a DSLR T Ring and then you might find that the whole lot will screw into a Barlow if yours is one that unscrews at the right point. I was quite surprised at just how many useful parts my rings and bit split into.  I don't have any 2" EP's but have frequently experimented with different ways of using my camera.