Which focuser

[billym44]

Looking at this question from the SCT point of view, more specifically a Meade LX200 GPS but I think it's a general question. I've been reading a lot on various websites recently about focuser upgrades. There seems to be two trains of thought. One a Moonlite focuser, which screws on the back of the SCT and replaces the electric micro-focuser (in the case of Meade), or option two, the Starlight feathertouch, which replaces the Meade focus knob mechanism itself.

So the question open to all is, which is the better option as an upgrade?

[Astroboffin]

Hi,

I also have a meade SCT, and I have the meade zero image shift microfocuser, and hands down go for the crayford type on the back, as it will get rid of all mirror flop which is common with all SCT scopes, use the normal focuser to get close then finish off with the rear mounted crayford.

It's even more useful when planetary imaging at high f ratios, while getting a planet in the centre of a small sensor, only to alter focus slightly using the stick focuser and .....it's gone of the screen due to slight motor flop.

The moonlight ones are expensive and more so for the electric version, like I said I use the meade 1209 electric version and find it an absolute must, especially for planetary work.

The feathertouch are superb, but they won't deal with the international mirror flop associated with an SCT scope.

Hope that helps

AB

[billym44]

Hi AB

Thanks for the post. Just to clarify do you the crayford focus in addition to the Meade micro-focuser?

Regards

Bill

[Astroboffin]

No,

The meade zero image shift 1209 is a microfocuser but it is a crayford design, that is just what it is called, the feathertouch micro focuser is completely different as that one just replaces the stock focuser, but they both have the word microfocuser in there name.

AB

[Astroboffin]

No,

The meade zero image shift 1209 is a microfocuser but it is a crayford design, that is just what it is called, the feathertouch micro focuser is completely different as that one just replaces the stock focuser, but they both have the word microfocuser in there name.

AB

I only have the meade one and not the feathertouch version

[billym44]

Ok, thanks for clarifyiing. I have the Meade electric microfocuser (the 1209?) that came with the scope but have had a couple of issues with it wanting to detach itself from its retaining adaptor. I'd previously understood the crayford design to be something completely different and just a smoother manual operation?

[Astroboffin]

Ok, thanks for clarifyiing. I have the Meade electric microfocuser (the 1209?) that came with the scope but have had a couple of issues with it wanting to detach itself from its retaining adaptor. I'd previously understood the crayford design to be something completely different and just a smoother manual operation?

Yes I know what you mean about the means of attachment, I think I commented on that in another thread you started.

Yes when I say crayford I mean the way the focuser moves, the manual ones and the meade electric one are the same in the way the focuser draw tube moves in and out, but obviously on the manual ones you can move by hand, the meade one, as you know is all built inside the focuser and can only be moved by the motor, but the principal is based on the crayford design on both manual and electric.

Now it you went for a moonlight manual version, you could upgrade that at a later date with the stepper motor kit, then it would fit the manual and motorised category, as the motor is only fitted to one side and leaves the other focus knob for manual tuning.

Hope that explains a bit better

AB

[Earl]

The feathertouch replacement focuser which is installed like the moonlite will be the better option, but pricey,

[Astroboffin]

The feathertouch replacement focuser which is installed like the moonlite will be the better option, but pricey,

I think the OP is talking about the crayford style moonlight focuser that fits on the back of the scope, rather that just replacing the stock focuser and not getting rid of inerrant mirror flop.

AB

[Earl]

the feather touch is that style also , they do rnp versions too.

[Astroboffin]

the feather touch is that style also , they do rnp versions too.

Apologies, I did not realise that, sorry, I thought they just made the dual speed replacement style ones, for meade and Celestron SCT scopes.

AB

[Dave In Vermont]

The Meade focus-knob has been a problem for well over a decade. Meade will do nothing about it. There is a solution which requires simply understanding the problem, and fixing it. It's a kit - with instructions an 8 year old could follow - from a mechanical engineer named Pete Peterson:

http://www.petersonengineering.com/sky/ez_focus_kit.htm

This fixes the focus-knob. Following this, a larger diameter item - some people use the lid off a peanut-butter jar - mounted on the knob make it as smooth as silk. So try these fixes before spending a pile of money on Feathertouch and/or electric moto-focus items.

Of course, you can find something more pleasant than a lid off a jar. Some 'bling' is available.....

Clear Skies & Smooth Focus,

Dave

[billym44]

Many thanks to all for the comments and helpful feedback. I'm new to this site, but it's an absolute goldmine of information!