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Stiff focuser - options
Hi everyone
I have a Skywatcher 8" Classic 200P Dobsonion telescope, with the stock Crayford focuser that it comes with.
I find that it is a bit stiff to move the focuser wheels, so the image tends to shake for a second or two after focusing. This is fine for most things, but for getting a good focus on planets at high magnification it is a bit annoying, as the planet gets a fair way through the field of view while this happens.
Unfortunately, my stock lenses (10mm and 25mm, plus an entry level 2x Barlow), mean that I do have to change focus whenever I change lenses.
I understand that there will always be a bit of shaking when you touch anything on the OTA, unfortunately there doesn't seem to be a way to gently turn the wheels to minimise this at the moment.
From what I have seen on these forums and similar places, there are a few options here:
1) Motorised add-on to the focuser (Skywatcher auto focusing motor)
Good because you aren't touching the scope directly.
Also on special at my local astro shop, only $109 instead of $150.
Downsides are you are a bit locked in to using it all the time, need to disconnect the battery to stop it draining, apparently the controls aren't the greatest.
If I go down this route, I might upgrade the controller using the 4Tronix Focus RF Remote Control, which plus straight in and has better buttons and controls apparently.
2) Dual speed focuser
I'd probably go the Lacerta upgrade kit from 365 astronomy. 75 pounds, so probably around $160AU after conversion and delivery.
This would be easy to install, and let me have fine control.
My main worry is if the wheels would still be stiff, and so still cause shaking.
3) Trying to do some adjustments on the focuser myself.
Sounds like the stock focuser on the cheaper Skywatcher models is not the best.
I've read about people sanding down the flat part so it is actually flat, to get it to move better. Also about people taking out the default grease and putting in something different. I'm not sure that this would fix my specific problem though, some of these seemed to be about making sure the focuser held firm, which isn't a problem for me. My main worry here is making my focuser worse.
4) Replace the focuser entirely
I'm not really interested in this, the prices to get anything seem to be half the price of my scope. Maybe down the line.
My inclination at the moment is to go for the motorised upgrade, but I thought I would check in with some people who know a lot more about this than I do. Would I be passing up on an easy home fix? What do people think would be the best approach here?
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