I figured out that my lack of being able to do more than 30s exposures without trailing was partly due to not properly balancing the ED80/350D on the EQ6.
In fact, I didn't really balance it at all. I didn't realise how much it would affect the tracking.
But the other night when I took my NGC253 image I did make attempts to balance the scope properly and was able to get 60s exposures without trailing, and went 90s with just a little trailing.
But balance still wasn't 100% right. I couldn't get the balance right in DEC. With the 350D and finderscope attached to the ED80, I moved the dovetail as far forward as it could go in the mount, and I moved the scope as far forward as it could go in its rings, but it was still too heavy towards the camera end.
It's like I need a counterweight on the dewshield end of the ED80.
How do I balance it properly? What do I need to/what can I use to balance properly in DEC by adding more weight to the objective end?
I found that I had to remove the short rail on the underneath of the scope to get the tube far enough forward to balance out the camera setup.
Simply took the focuser off (3 screws around the end) and removed the internal nuts from the rail, then plugged the holes with rubber covers. The scope now has plenty of movement.
There is nothing wrong with adding counterweigths Mike. Sticky Velcro and then get some bits of lead (Surf sinkers and flatten them if necessary with a hammer ) and attach sticky velcro to them. Works a treat. Or get a smaller bolt for the front ring so it doesn't stick up so far and hit the bottom plate.
I may have the same problem with my ED80/40D combo too!
Is this where a dovetail and mini counterweight system similar to the attached pic would be handy?
Andrew, magnets would be the ideal solution, except that everything up front on an ED80 is aluminium. The OTA, the Dewshield, the Dovetail etc.
Mike, if Kate doesn't mind sewing things up for you (or you could try yourself), you could sew up an item like a miniature money-belt. It could velcro around the Dewshield, and in the little pockets you could add or take lead weights (sinkers etc).
Just an idea
Well my Saxon doesn't let magnets stick to it.. I've had to use duck tape to tape a counterweight to the front end of my ED80 to balance it when the cameras (350D on the ED80 and DMK on the guidescope) are in place.
My thought was a ring of sticky around the tube, then each weight has a piece stuck to it on both sides and then a piece of velcro wrap over the top. Aint nothing going to move then. That velcro wrap is brilliant stuff
I need to do something similar but I haven't gotten round to it. I just make sure I shoot either directly east or west, that way I can balance it using my counter weights
Another option with the velcro would be to stick strips of it (about 100mm long or longer if needed) about 3-4cm apart from the cell back towards the focuser all around the circumference. That way you could put velcro wrap lengthwise over the top of each weight and if you needed to lighten the load you could remove individual weights much more easily.
Ugly! Ugly!!! No way. This is like Dob Modding (remember that grasshopper ). It gives your scope character. It gains you notice when you are out on the imaging field "Gee Mike that is a great idea. I'll use that on my setup". Ugly Pfft. It's all in the eye of the beholder.
But silver duck tape, now that is just chincy and crass. Black if fine, but silver....puhlease.
![[1ponders]'s Avatar](../vbiis/customavatars/avatar45_9.gif){kind=avatar}
) and attach sticky velcro to them. Works a treat. Or get a smaller bolt for the front ring so it doesn't stick up so far and hit the bottom plate.
I had a quick look at my Orion ED80 and I can attach a magnet to the OTA (but not the dew shield). 
