Crayford Focuser for Celestron XLT102?

[nickgilboy]

As a newcomer, like many I'm finding my way in the dark, so to speak. I have a Celestron XLT102/F10 and have recently upgraded the diagonal to a William Optics 2" Dielectric. This is a beautifully engineered component and, as such, I was looking at purchasing the William Optics Crayford focuser to go with it, before I look at additional eyepieces (I have a solitary 25mm EP which came with the scope - which is giving lots of enjoyment). Does this make sense? Is it right to improve the various components in the light path before looking at adding to/improving the eyepieces? Is the new focuser an overkill for the XLT or can the scope do justice to this £180 add-on? I'm mindful of trying to spend money on components that could be transferred/used with future OTAs and realise the focuser would have limited use elsewhere but could nonetheless be used on a refractor of up to 6" diameter (I dream!). I'd much appreciate some feedback on this to help me make a sound decision. Many thanks.

[yeti monster]

Unless your existing focuser is causing you needless grief, I'd suggest spending on top shelf optics first, as a focuser will only focus a mediocre EP just as well as it will focus a high end one. The resultant image is what is most important, IMHO.

[david o]

I'll second YM on that.

The stock focuser should be more than adequate for normal use. If you've got cash to spend, get some decent EPs to supplement the 25mm that came with it.

[jgs001]

Another vote for not adding a Crayford. If you're having issues with slop on the drawtube (it moves when you adjust focus) then placing strips of PTFE tape along the drawtube will pack out the spacings and stop that nicely. I've done that with both my scopes, including the stock R&P on my imaging scope the Celestron 80ED and it works a treat.

[robhal9000]

One more anti crayford. They are a very nice luxury, but get the EPs first.

The HR planetary range which Modern Astronomy stocks are nice for less than 50 quid.

Eyepieces @ Modern Astronomy

The paradigm range also called 'explorer dual ED' are sometimes available on Ebay. They only have a 25mm at the moment.

1.25" 25mm 60 Degree Explorer Dual ED

Eyepiece on eBay (end time 09-Jun-10 11:19:19 BST)

The William Optics range of SWAN are nice 2" EPs 33mm and 40mm and are around 80 quid from FLO. I find the eye relief a bit tight, but a nice wide view.

William Optics - William Optics SWAN eyepiece

For high mag lunar and planetary. The WO SPL range are very good. 70 quid each.

William Optics - William Optics SPL eyepiece

Baader Hyperions are a good choice if you can afford them -93 quid each, but with the finetuning rings they can be adjusted to a lower focal length. They also operate as 2" EPs again with a different focal length, so you get 3 or 4 EPs in one. The 21mm is particularly good because in 2" mode it becomes a 32.2mm and with both fine tuning rings a 1.25 14mm. They are pretty chunky:-)

Baader Planetarium - Baader Hyperion 68 degree eyepiece

Baader Planetarium - Baader Hyperion Finetuning Ring

A Baader contrast filter may help with any chromatic aberration or one of their 'fringe killer' or semi APO filters. FLO stock them all in their filters section.

And one of these to keep your shiny stuff in.

Small Flight Case : Flight & Rugged Cases : Maplin

Have fun.

[pbyrne]

Buy more eyepieces, you'll be glad you did.

Rob has listed some excellent examples, I have personally used the Hyperions in the past and can't recommend them highly enough.

[johninderby]

One thing you might consider is to see if someone is upgrading their Skywatcher ED-PRO refractor that comes with a single speed crayford and is selling the standard focuser. It would be a straight replacement with your scope. It's not the best crayford in the world, but if you can get it for £30.00 or £40.00 it's a good budget alternative. Also you can buy a dual speed upgrade for it for about £50.00 latter on if you wanted to.

John

[Moonshane]

although in general I agree with the additional eyepieces rather than the focuser replacement, I have actually made this modification to my OMNI 120 XLT refractor so can comment on the differences.

I'd also agree that you can definitely improve the slop by tightening (a little) the small grub screws on the top on the housing.

I actually bought the Skywatcher version which is almost the same but a bit cheaper. I was lucky and got one new for £109 delivered but they are generally £129 now I think. It's a straight replacement with a little twisting and shouting if your sleeve is like mine. Went in OK in the end though.

For me personally, it has made a massive difference to my enjoyment of the scope and allows me to attain better and more rapid focus. I was so impressed I bought a used newt version for my dob too (for £95) - only got to wait until 25/5/2010 (my anniversary!) to use it

Go for the eyepieces first (some good recommendations above) given you only have the one and see how you go. again buy the best you can afford as these will stay with you for longer than most scopes. I'd also recommend fewer great ones than lots of cheap ones for the same reason. By the way, the WO SWANs work really well with your scope (and mine of course - well the 33mm did) but I'd tend to go for something that will work well in a faster scope too if you may consider eg a dob in the future. Used items are often great value too and I went down the used Tele Vue road as you can pick up Radians for about £100 used and these will work in pretty much anything common - also, if you buy used you will generally be able to sell for not much less if you don't get on with it. this especially applies to upper level brands like Tele Vue. don't rush into anything though, especially spending loads of cash!

your logic is sound by the way in that you will retain the good diagonal and eyepieces etc and can always transfer the focuser if you get one and it's another Synta pattern one.

if you wondered what one would look like, there's a photo of mine in this thread http://stargazerslounge.com/diy-astronomer/99451-final-pics-tripod.html

cheers and enjoy the scope!

Shane

[nickgilboy]

Many thanks to all of you who responded. Your feedback and advice really is appreciated and the message seems to be clear - go for the eyepieces not the focuser. And thanks to Rob for taking the time to provide all the links and Shane, glad to know that the Crayford is worth considering as and when I might find the money.

[Moonshane]

Many thanks to all of you who responded. Your feedback and advice really is appreciated and the message seems to be clear - go for the eyepieces not the focuser. And thanks to Rob for taking the time to provide all the links and Shane, glad to know that the Crayford is worth considering as and when I might find the money.

there's always choices of course. for the same money as the focuser you could probably buy a 6-8" dob (well not far off anyway) to compliment your frac!