Most used stuff:
AT72ED, 10" custom Newt, Baader Maxbright BV,
Canon 1D & 70-200 1:4L, Pentax 8x40 PCF WP2
4.5", 6", and 10" Newtonian astrographs.
2 ST80s; ED80; 3 CCD cameras; 5 EQ mounts: all polished, tuned, and modified.
The rule of telescope features: aperture; equatorial tracking; or low cost. Pick any two.
The Cheapest Astronomer in the World gets excited by Jupiter. Builds dob, builds eq platform, arranges to borrow webcam...
tybee ISO-8601 Please!
Black Creek Observatory C11 EdgeHD C8 AT6RC Eon80mmED
Quote:When I could get it balanced, I was able to do webcam on Jupiter for 60 seconds at a time. The thing was hard to manage but when tracking right it was not particularly shaky.B
Quote:I've got a 8" f/8.5 on a Starfinder. If I wanted good performance out of the mount I'd go for a short focal length 8" or better yet a 6" f/8.Putzing around with the mount has delivered very small gains in my experience. I'd save for something more up to the task.Here's your mount......... LINK!!!!!
Quote:Shaky? What kind of surface is it on and are there any vibration pads under the feet? I just finished converting mine to be used as an astrophotography mount. Please provide more insight as to how and where the mount is shaking.obin
Quote:My StarFinder 8" was a rock on the "port-a-pier" EQ it had. Double check everything is tight, including the declination axis. Snug that up by loosening the "setting circle" (quoted because it is kind of a rinks dink set up...), have someone push down on the saddle, and retighten it. That alone does wonders for the mount!Also, if it is missing the rubber shoes, hunt down a suitable replacement.Or, sell it to me :-P
Quote:Many years ago I started out with a Meade DS-10 which is basically the same scope as the Starfinder. I ended up putting my mount on top of a 4” water pipe screwed into a fire hydrant flange. The whole thing was bolted to a 15' x 20' concrete pad at least 24” thick in the center with 8 12” long 1/2” bolts. It was rock steady. My damping times were close to instantaneous. I regularly observed luna and Jupiter at 450x + and this was with the original 45lb sonotube.I would say you need to upgrade your pier.Tracking on the other hand wasn't so hot. You can't make a silk purse out of a sows ear.
Meade 10" Starfinder EQ customized /w EOS T3
Quote:Quote:When I could get it balanced, I was able to do webcam on Jupiter for 60 seconds at a time. The thing was hard to manage but when tracking right it was not particularly shaky.B In the other thread I think you saw my stepper motor upgrade for the Starfinder mount. Last night the mount was so stable that my biggest problem was with the heat coming off of the mirror. Jupiter was rock solid in the eyepiece with no vibrations. The stepper motor is much better than the AC synchronous in that regard.The only time I noticed vibrations were when I knocked into the telescope or the feet by accident. They still dampened quickly.obin
Quote:at one point I had issues with my starfinder eq.. It ended up to be the ra worm had to much play between it and the main gear.. +1 for checking everything is snug...
Quote: Obin, thanks for the response. I'll post some pics with more detailed explanations, but the gist is this:• Home built dolly with large locking casters• Vibration pads (standard Meade style)• Stock portable pier• "Home built/modified" dove plate in place of original steel strapsI'm sure that my dolly design could be improved, as well as a complete overhaul of my poorly designed dovetail plate. I can't remember if I mentioned it in the first post, but I use a binoviewer or a 2-ish pound EP with a 50mm extension tube. I am aware that this taxes the mount a little extra.
Quote:Keep the nylon bolt. Anything else (except brass) will mar the shaft, causing shifting when clamping. Not good!!!!As for the RA axis gap, it can be taken apart, but it's tough! There are plastic bushings inside you can grease while you are in there. It's fairly self explanatory once you start stripping it down. You may need a small amount of mass persuasion (small dead blow hammer) to bang the shaft out.
Quote:That Byers unit is cool. I've seen it before., but thought it was a custom build. I didn't realize there where others like it.
Shane in black-zone New Mexico
Quote:I'm not sure exactly what "backlash" is. But if it's a degree of wobble between the teeth and the worm then I can see how that might be an issue.
Quote:Yeah my Starfinder GEM has slop in the (backlash) in the worm and gear too. Haven't tried to adjust it out yet, but there is a screw to adjust that.And to obin robinson I'd love to see pictures and info on your stepper conversion being as the motor is missing on my GEM
Quote:Every gear requires a small amount of backlash. With the gear being plastic, I'll bet that there's a ton of runout/out of round to it as well. This is why you "cheat" and intentionally leave the RA axis slightly out of balance, so you are always in a loaded condition.
Quote:Do the vibrations match the frequency of the motor vibrating and/the small gearbox? Is there a resonance building up causing the tube to vibrate like a tuning fork?
Quote:The clutch does have some lag in it so you need to lead the object you wish to observe a bit. You can try adjusting balance and clutch tension......it's a can of worms though. Here's a LINK for replacement bushings if that's any help. Some folks are really liking this mount.....so the answer is out there somewhere. Good luck!
Quote:When setting balance, disengage that slipper clutch! I forgot to mention that earlier! I think there are three screws on the tension plate. You can always completely remove it, clean it up, and re grease it as well. Then use a marker, and mark the tube for both visual and AP setups. That way you can just set it and go each time.