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Quote:I notice that the pointing accuracy is quite useablein the EQ6 mount after doing a 2 or 3 star alignment however-after using PHD guiding for say one hour -if I want to recheck my focus on a bright star -if I slew to a known bright star I lose the pointingaccuracy. I need to use the hand controller to get the starcentered & then when I slew back to the object it's no longer there in the field of view.I then need to re-align the mount to find my imaging target.This only happens after using PHD guiding.The reason?I think it's because the EQ6 doesn't have digital encoders& has to add & subtract all the guide movementsover a long time - which it can't do accurately.In other words after say one hour of external guidingfrom PHD the pointing accuracy is lost without re-alignment.Am I right or am I just imagining this?
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Quote: No idea why you are losing your alignment accuracy, but it doesn't have a thing to do with encoders. AFAIK, if the mount motors move, the mount knows how much. No one else has reported this problem, and I certainly have not had it.
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Quote:Apal, are you using EQMOD with your EQ6?
The gazillion star alignment in EQMOD lets you choose as many stars as you want. I usually add just a few at first and some more as I move around in different part of the sky. I have an NEQ6 with EQMOD and I don't lose my pointing accuracy ~ not to the extent you are describing anyway.
Quote:No - I don't use EQ mod -
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Quote:Quote:No - I don't use EQ mod - With the built-in firmware your goto accuracy is dependent on the quality of your polar alignment and, as has been mentioned, on the orthogonality of your optical tube.Orthogonality won't explain why you can't go back to a previously successful object - but polar alignment would, as would any slop in your mounting arrangements or mirror holders.
Orion 8" f3.9 Newtonian, Atlas EQ-G Cooled Canon 1100Da SSAG on 50mm Finder pocketrubbish.com
LS60THa/B1200 Cerevolo 8" F5 MN Orion 11 SCT Tak EM200, Meade 6" F5 Newt, Starblast 4.5", ETX 90 C6 SCT, Meade 90 mm F9 refractor Meade 10"SN Canon T3, Mallincam Extreme
Quote:use AstroTortilla. Best thing since sliced bread (and the Mach1..)
Canon T2i Unmodded
Orion Atlas Mount
Orion SSAG Mini Guider
Capture Software - Backyard EOS, PHD, EQMOD
Meade 2120 LX3 (Now on the Atlas and getting used a little!)
Quote:Question (1):Could the power supply be affecting the operation of the mount to cause bad pointing error accuracy?Question (2)Is there any other reason that the pointingaccuracy is so bad?My field of view is the size of the full Moon -I should be able to get the galaxy dead center or at least in the frame.Question (3)Am I doing something wrong with WorldWide telescope?I thought the downloaded version would work the same as the online one..
Quote:Quote:use AstroTortilla. Best thing since sliced bread (and the Mach1..) And coupled with EQMOD you don't even have to do star alignments anymore. It can be all automatic.
Orion SSAG/50mm finder
Antares f/6.3 FR/FF
TV 32mm Plossl
Quote:I hear you about downloading yet another program that doesn't work, but Astrotortilla has been a god-send for me. I set it up using this tutorial, and my slewing and hunting days are completely over.
Quote:It's possible that your EQ6 is missing stepper counts. Too tight worm mesh, or not enough power to the stepper motors.
1987 Meade LX3 2120 10" SCT on hypertuned EQ6 Pro (Currently Broken)
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Quote: This was obviously an orthogonal error but the mount's firmware didn't take care of orthogonality errors like Celstron NexStar mounts can.Peter
Quote:Does the hand controller on the EQ6 keep the sync points from the last time it was used? ( I don't have a hand controller)The only time I EVER have a pointing problem is when EQMOD loads the sync points from a different session, and I can tell right away because things aren't in the eyepiece or not centered. With 6 align points on each side of the meridian (big triangles), every single target is in the center of the EP with a half a degree FOV.If you are 1.8 degrees out on a goto, something is horribly wrong.The guy you quoted meant to say arcSEC, not minutes.
Quote:I'm new to the EQ6.PE seems OK +- 7 arc secs and well managed by using PEC but the pointing accuracy appears very poor.Ive done a couple of TPoint models (88 and 48 points) and the best Ive got so far is around 1500 arc secs - thats 25 arc minutes.My old EM200 did around 45 arc secs. Polar alignmen is OK 1.5 arc min in azimouth and about 10 arc minutes on the elevation.Ive fastened every nut and bolt on scope and mount. Is there anything I should be looking out for?
Quote:I used to have Atlas EQ-G supporting C-11 about five years ago. I was never happy with it's pointing accuracy.
Quote:Another thing to mention is the carrying capacity of the mount. My old C-11 scope plus accessories like guide scope (now using OAG), imaging stuff, etc. were pretty heavy. The OP's scope appears to be pretty big, long and heavy. It might be possible that heavy carrying load might affect the pointing accuracy. If you or your friend has a lighter scope, try test the pointing accuracy with a lighter scope.Peter