Skywatcher Auto-focuser

[long_arms]

Hello,

I'm thinking of treating myself to an auto focuser ( I know its not really auto as is always pointed out).

I have looked at a couple of reviews but they seem to be from a fair time ago so I thought there isn't any harm in posting again.

I wouldn't say I have a problem with getting focus with my single speed crayford, although with the IR filter on jupiter I definitely found it a little tricker (took longer). Anyway it seems to be taking me a long time that is wasted especially with the weather.

Couple of questions:

Has anyone come up with a mod yet so the focuser can also be used manually? (I'm not too bothered about this but would be useful).

Also, does it lock the focus in because of the gears and whatnot? Meaning that you dont need to use the little screw underneath? (which changes the focus obviously) I never lock the focuser with the screw as I can never tell if it is still in focus afterwards despite tweaks.

All reviews and help appreciated,

Dan

[JB80]

Can you lock the focuser?

I never knew that, I'll check my 150pl for that.

Anyway, there is a resistance when the auto-focuser is attached, I wouldn't say it's a lock but it would take a decent knock before the focus would shift. You have to be firm to turn the focus wheel when it is attached.

I really don't think slippage would be much of a problem here.

As for using it manually I'm sure somebody who took the right approach to it could engineer a method but I just keep a small allen key at hand and loosen the auto-focusers grip when I want to use it by hand and then tighten it when I want to make fine adjustments with the focuser.

Also a bahtinov mask is extremely useful because then you can focus on a star first then turn to Jupiter. Check the FLO website, I got one from there.

[long_arms]

Yeh its a screw underneath, I can never get it so that its in focus with it locked however so I never bother.

Thanks ! the resistance certainly sounds good! And that sounds very easy to do, I'm glad a simple allen key can do it (not sure why I would want to change it manually but nice to know)

I will certainly be getting a bahtinov for deep sky stuff and a dslr. But for planetary/lunar I prefer to do it by eye with a moon or a crater on our moon. Not sure I could trust a bahtinov fully for lunar especially...I'm sure its perfect, I just know I wouldn't trust it.

Dan

[Stevp]

Not sure if you saw this a couple of days ago, might be useful

http://stargazerslounge.com/index.php?/topic/178475-Getting-Skywatcher-Auto-Focuser?-Mmm..NOT?

[long_arms]

Not sure if you saw this a couple of days ago, might be useful

http://stargazerslou...user?-Mmm..NOT?

DUH! I really am pants at searching around this forum. Thanks for the link...feel a bit silly now.

[JB80]

Yeh its a screw underneath, I can never get it so that its in focus with it locked however so I never bother.

Thanks ! the resistance certainly sounds good! And that sounds very easy to do, I'm glad a simple allen key can do it (not sure why I would want to change it manually but nice to know)

I will certainly be getting a bahtinov for deep sky stuff and a dslr. But for planetary/lunar I prefer to do it by eye with a moon or a crater on our moon. Not sure I could trust a bahtinov fully for lunar especially...I'm sure its perfect, I just know I wouldn't trust it.

Dan

Ahh, I see the knob now. It's that big silver screw that you can't miss. Just goes to show that I have never had need of it before so never paid much notice.

For some reason I am always wanting to use it manually, I think because the focuser only has two speeds, 'slow' and 'not as slow'.

I guess it can be a little bit fiddly to do it in the dark because it's only a small key but it's still easy enough.

A lot of people do use that method for Jupiter and seem happy enough, still it comes down to what you are comfortable with.

[ollypenrice]

If your EPs are not highly parfocal or you like to use a Barlow on occasion then not having a release for the motor focus would be pain, I'd say. It moves pretty slowly and is intended for imaging. We use the humble Skywatcher one on the 14 inch here and it's fine for this purpose. It does hold the focus quite well, though it's a Baader Steeltrack so slippage isn't a regular occurrence. Not unknown, though. GRRR!

Olly

[AllanJ]

I have one on my 10" dob, very useful. I also took the other knob off so that I would not be tempted to try to manually focus it!

[brucen]

I use one on my 130P but that is mainly used with the webcam. It has improved the quality of my images no end and saves me a lot of time as I no longer have to spend ages finding things as they disappear from view whenever I touch the focuser. I gave up using a 3X Barlow with the webcam with manual focusing as I was spending more time re-centring whilst focusing than filming. With the auto focuser I can find something once and it stays where it is (more or less) while I focus. Yes it takes appears to take longer to focus when not using the webcam but if you take off the time you would have to wait for vibration to stop between adjustments I don't suppose there is much in it.

[Uhwaz]

I love mine even if you change EPs you still save time as you dont have to wait for scope to stop wobble between nudging focuser ( i have 200p on EQ5 and that wobbles a good bit )

I do a bit of AP too and it holds cannon 30D no bother without losing any focus

[Merlin66]

I use the SW focuser motor on the ED80 for solar imaging - I'd be lost without it.

I also made up a belt drive for the C11 and use it with Shoestring FCusb to control from the computer......

(Note for Jarrod: It's amazing what you can do with Vegemite lids! ;-) )

[jabberwocky]

Even with my heaviest ep, a 30mm ES 82, the focuser doesn't budge when using the auto focuser, the motor is pretty solid, good job because for some reason I cant get the focuser lock screw back in the focuser after fitting the auto focuser, it just won't screw back in.