Posts Made By: Geoff DAHL

I have been having trouble getting any good alignment on my Nexstar 8. I have tried both the Auto Align and 2 Star alignment methods and the resulting goto's never place the object in the eyepiece (32 mm). (and sometimes around 5-10 deg off).

I have made sure the telescope base is level,
Align the stars with a 9 mm eyepiece,
Pick stars between 40 to 80 deg apart
Use the AC Adapter to ensure it is not poor batteries,
Tried various and different stars for alignment.


For those in the know, a few specific questions...

*Do I need to get a wedge to get better alignment on the goto? Would it make any difference. (or would it just make it even harder to get an alignment)
*Should there be any difference between the 2 star and auto alignment results? (I often use the 2 star since that eliminates location/time/date errors.)
* Do I need hyper accurate level on the base? There is no good spot to place a level on the base, so I have used various methods like using a small level that fits on the battery lid, leveling the tray below, using the same length tripod legs on a level surface...

Any other suggestions?

Thanks

Geoff

Can anyone recommend a connector or adapter to provide both a serial and parallel (printer) port connections for a laptop that only has USB?
I would like to be able to use it when no power is readily availble as well. (but 12v car battery is)

I want to be able to connect my webcam for guiding (usb), 300D camera (parallel/printer) and LX200 auto guiding (serial). I only have the 2 usb ports so I was thinking 1 for the webcam and ther other for both serial and parallel (printer) port.

Ideas?

Thanks!
-Geoff

Can anyone tell me what the amperage/voltage outupt is for the Meade lx200 power supply/AC Adapter?

I was thinking instead of buying one, I would build an adapter from one of the several power adapters I already have. I have 12 v supplies at anything from 300 to 1500 mA and even a couple 18V adapters.

-Geoff

Well, I finally got a chance to try out using a wedge on my LX200 last night. I found that the tracking& goto are MUCH worse than when I use in Alt/Az mode. I know my polar alignment was probably not the best, but I would have thought that the computer could account for that with the plolar 2* align. Is this not the way it works?

This leads to some other questions.

*How necessary it it to get the scope into the polar home position 'exactly'. When I was rotating the scope in RA, I was getting some star shift, but not too horrible I thought.

* When in polar mode, does the computer not use the Dec drive to correct for possible errors in polar alignment?

I set up the scope with at 2* polar align using the same 2 stars I used in alt/az mode the other night. I had about the same accuracy (9mm eyepiece) on both nigths, only when I used the wedge both the goto and tracking were off much more.

Thanks for any help.

-Geoff

After last nights problems trying to learn to autoguide my lx200, I was hoping that someone could give/point me to some more information or tutorials or better auto guiding software.

I have a long exposure modified Toucam that I wanted to use for autoguiding and I was trying to use the AstroSnap software. However whenever I let it try to autoguide, it would eventaully start to 'runaway' in RA. (The lx200 is polar mounted/aligned.) I immediately thought I just had to reverse the axes, but this did not work, the same thing happened.

I was able to use the controls on the software to slew and move the scope ok, but somethign is wrong.

Should I be using different software? Can anyone recommend something free or at least inexpensive that can use a Long Exposure modified toucam for autoguiding? Or can I get a pointer to more information or troubleshooting steps?

Thanks!

-Geoff

I would really appreciate help on this. I have tried posting this to a few different forums, but to no avail.

Below is the full explanation, but basically whenever I connect my telescope (lx200gps) to the computer for guiding, West motion (Hitting the west button from the computer) does not work properly. (N, S and E does) The hand paddle works too, the problem is just from software, just the west button. (or when RA reversed, the East button) Whe I hit it, I get the motion, then it immediately 'rubber bands' back to close to the old position. I get similar problems with computer guiding ending up with run away motion.

Anyone got some ideas...?

Thanks

-Geoff


>>>
Hi All, I would really appreciate any help and pointers to the
problem I am having... I think it is driving me insane... :-<

I have a 10" lx200 gps (polar aligned) with the 1.6b firmware. I am
using a long exposure modified toucam and either AstroSnap or
GuideDog. I have problems with both of them. Everything seems to
work fine when using the hand paddle to self guide, (at guide rate or
speed 1) but I can not get either progam to auto guide.

When i use the telescope control buttons in the program to move or
nudge the scope in any direction, it works just like the hand paddle
EXCEPT for west. North South and East movement are just like the
hand paddle. With West, the move starts correct, then 'rubber bands'
back in an 'east' motion. Reversing the RA directions does not seem
to help. The bad motion is always after the correct motion is
done. With GuideDog it goes back to almost the same position it
started from. (With anyplace between a 500 and 2000 ms nudge) With
AstroSnap it seems to jump by the same amount (15 arcsec or so) no
matter how long i hold the west button down.

When I try and use the autoguiding sofware to control motion it gets
out of control and the star always moves off like i was hitting the
east button when it tries a correction that would be a west motion.
Again reversing the RA direction does not help.

I have tried re-training my drives a couple times, turning PEC on and
off rebooting the computer, various backlash (0% 60% 100% 130%)
pulling my hair, ....

Anyone seen this problem before?
Is there a setting on either the telescope or the software to
compensate for this?
DO I need a different version of the firmware? IF so then what?
Woud this be a problem with the telescope that needs to be sent to
Meade?

Thanks for the help.

This is probably a stupid question, but if I am using a dew heater strip, should I use a dew shield as well? If it makes any difference, I have (what is labeled as) a 20W dew zapper on a 10" lx200. I have been using a homemade dew shield with the zapper, but it recently cracked in the cold and I was wondering if I need it.

I finally got a night of good enough seeing to get a reasonably good capture. In most of my efforts I can only see the bands, but last night was much better. (I have been gleaning tips from these boards as well, thanks to all that supply them.)

Comments and suggestions welcome.

-Geoff

P.S. I was wondering how people quanitfy the seeing where they are. I know there is an official calibrated way to do this with a specific scope, but how about for the rest of us? Can someone give me a pointer to method to quantify it with a SCT? Thanks.

I was playing with my new CCD camera (SXV-H9) aligning guidescopes and focusing around Jupiter when I noticed what looked to be a nebulosity just off of Jupiter. Is this just an internal reflection of Jupiters light? If so, any ideas how to get rid of it? I was assuming I was only getting it due to the strong light from Jupiter....

Thanks to all, I finally got it working. I think it was a combination of taking too long to align the stars and the backlash.

Last night I had everything ready before starting a 2 star alignment (star choices, eyepieces, focus, ....) I also made sure to finish each align star using the up and right arrows (same direction when the scope finishes a goto). The objects I tried all appeard within the eyepiece.(32 mm) I used Rigel and Pollux and found that for objects around or 'between' the two stars, the aligment was better. A goto for farther away from the align stars seemed to be worse.

For Mauricio, the backlash effect is like the 'wiggle room' in the gears. If you are slewing to an object and change the direction of slew to the opposite (say up then down) you can hear the motor moving for a few seconds before the image starts moving (at slower speeds). You can imagine that the gear has tension on one side, then as you reverse direction, it unwinds the tension and then builds it on the other side of the gear before it actually moves. The net effect is some indeterminace in a position with respect to the gearing.
Not sure if that is exactly correct, but it is my understandign anyways. :-)
Not sure what to say about the photo's, but with the alignment last night, ojbects would mostly stay within a 9mm eyepiece after they were centered.

Thanks again to everyone that chimed in!

-Geoff