Skywatcher ST80 imaging

[Hawkeye]

Is there anyone using the ST80 for imaging and if so how are you managing to get good focus?.

I just don't seam to be able to turn the focuser the small amount needed.....

Sent from my HTC One using Tapatalk

[JessicaFaye]

I have an ST80 but haven't started using it for imaging yet. What are you trying to image, I think really it's only good for planetary imaging as far as I'm aware not ideal for DSO! Anyway when it comes to focusing it for imaging I can't really help but I'm sure someone on here can good luck!

[Bizibilder]

You may find that it is suffering from "Skywatcher gunge" or grease, as it is more commonly known.  It is terribly sticky stuff and can make focussing very difficult.  The best thing to do is dismantle the focusser and clean it thoroughly with white spirit and then a bit of meths or similar.  Let it dry and re assemble with a little "white lithium grease" (available from most cycle shops).  It will be considerably smoother and much easier to use.

If you have liveview on your camera (or it is connected to a computer) then you could make a cardboard Bhatinov mask (cut out with a sharp modelling knife) that will help you get perfect focus easily every time.

http://astrojargon.net/MaskGenerator.aspx

[lensman57]

Is there anyone using the ST80 for imaging and if so how are you managing to get good focus?.

I just don't seam to be able to turn the focuser the small amount needed.....

Sent from my HTC One using Tapatalk

The ST80 was never meant for imaging . It has a crude rack and pinion focusing mechanism designed at best to achieve focus with  the supplied EPs. You can attempt to clean the rack from dirt and use special lubricant to try and make the action smoother, you may also have to tweak the lock screw to get a balance between smooth motion and firmness, also be very very gentle with your movements as the point of focus nears. 

A.G

[idigitize]

Focus can be a little fun, I've managed to get a few pics but had cloudy nights for ages too

I've not done all the tweaks and new grease yet but will definitely give it a go soon.

I don't have a laptop for focussing but am using an eye-fi card and my ipad. I can record raw+JPEG and send the JPEG to my ipad to check focus.

It's not quite as good as a laptop and continuous live view feed, but the next best thing, means I can check focus on my ipad screen as I tweak it.

My best effort before the clouds...

[steppenwolf]

Focus can be a little tricky with the ST80 but you'll get used to making tiny adjustments - I found that just 'brushing' the focus wheel with my finger when I was near to the correct focus position was all that was required for the final tweak.

[Guest]

If you going to use for imaging then swap,the focuser for one of these, I have and never looked back, although it is nearly as much as the scope was, but makes it into a great little wide field imaging scope, as they do,have very good optics.

http://www.teleskop-express.de/shop/product_info.php/language/en/info/p6274_TS-2--Crayford-focuser-for-Refractors-with-telescope-adapter.html

MM

[happy-kat]

Does that focuser have done tunning or is it just easier to minutely adjust it?

[Hawkeye]

Ok, so I have cleaned out the skywatcher grease and replaced it with the white grease, then fitted the focus motor from my other scope. The focuser now moves in and out really smoothly and no play.

I also noticed that the lenses were held a little tight so might have been some pince errors too.

So all I need now is a clear night so I can give it a try...

Sent from my HTC One using Tapatalk

[Nillchill]

Why not fit a powered focussed, it will allow you to make minute adjustments, and you won't cause vibration in touching the scope.

And its a lot cheaper than replacing the focuser.

[Hawkeye]

That's what I have just done... Looks to work really well on the bench, just need to test it with the camera attached.

Sent from my HTC One using Tapatalk

[Guest]

Does that focuser have done tunning or is it just easier to minutely adjust it?

It is just really really smooth and a hell of a lot more solid, weighs a lot more too, but a dream compared to the old one.

MM

[Guest]

Ok, so I have cleaned out the skywatcher grease and replaced it with the white grease, then fitted the focus motor from my other scope. The focuser now moves in and out really smoothly and no play.

I also noticed that the lenses were held a little tight so might have been some pince errors too.

So all I need now is a clear night so I can give it a try...

Sent from my HTC One using Tapatalk

You know you can adjust the tightness of the stock focuser by adjusting the two small Allen bolts on the focuser, not a lot of people know that.....as Micheal Caine would say

So you could tighten it up more of needed.

MM

[Hawkeye]

Yeah I did know about them.. that is how I have adjusted the focuser..

Sent from my HTC One using Tapatalk

[PeterT]

I love my ST80 for imaging.  Although I use it mostly for wide field viewing and auto guiding.   I put a Crayford style focuser on it, and use a homemade Bahtinov mask for focusing.  Here's a few 4x30sec shots shots with it.