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John,

I think a number of us have noted this. Indeed, Doc G., as I recall,
recommends you don't slew the scope at the default rate for "wear and tear"
reasons ISTR.

Bob (52 N/1 E)

At 22:07 31/05/01 -0700, you wrote:
>If you recall I posted a message a week or so ago about goto accuracy problems
>with my 8" LX200. Initially I getting about 1-2 degrees of goto accuracy. I
>made some minor tweaks to the OTA alignment and was able to get that error
>down
>to about 30 arc-min for large slews. However, I just realized tonight that if
>I decrease the maximum slew speed from "8" down to "5" then my pointing errors
>decrease to around 5 arc-min for medium slews (< 90 degrees) and around 5-15
>arc-min for large slews. Has anyone else experienced this increase in
>accuracy
>at slower slew speeds? It makes sense that this would increase accuracy but
>I've never seen this mentioned anywhere. The pointing error that I get at
>high
>slew speeds is almost entirely in RA and almost none exists in DEC. Also the
>error is always because the RA drive overshoots the target coming from either
>direction. I can live with a max slew speed of 5 but it would be nice to get
>the same accuracy at the slew speed of 8. The accuracy seems to get even
>better at slew speeds below "5" but anything below 4 or 5 really gets slow for
>long slews. However, I can handle the extra time for slewing if it actually
>hits the target. Are there any tweaks that can be made to the RA drive to
>improve this?
>
>If anyone wishes to try this to improve accuracy just keep in mind that it
>always defaults back to a slew speed of 8 at power up (6 for 12"). Also make
>sure you make the speed change BEFORE you do the 2 star alignment because it
>makes a big difference.
>
>I'm just so excited to be able to finally GOTO and have the object in the
>eyepiece!
>
>John
>
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