Tracking problems...again!

[04Stefan07]

Took some raw footage of the Sun today with my PST on my SLT mount. I swear there seems to be a tracking problem with my mount. Once aligned it locks onto the target then slowly drifts off bit by bit and then holds position.

Can I take the mount to a repair shop or something to get tested??

[l3gendluk3]

My SLT mount does that when my power source starts running out (powertank or AA batteries) although it did that only once because I rarely align it and ask it to track an object, so it might be something else. You should check your power supply and re-flash your hand controllers firmware and motor control firmware. A guide for which can be found here (http://www.celestron.com/c3/support3/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=1747&nav=0,255).
NOTE: The guide above is for the original Nexstar controller, if you have the Nexstar+ a guide can be found here (http://www.nexstarsite.com/OddsNEnds/HCFirmwareUpgradeHowToNexStarPlus.h tm).

If you have Windows 8, prepare for a wrestle with CFM!
Hope this works,
-Luke

[04Stefan07]

Thanks Luke I will have a look into this. I go XP installed on a VM so shouldn't have a problem.

With your mount does yours seem a bit lose when you touch it?

[04Stefan07]

I can also confirm that the power supply has enough power and I have not flashed my firmware on the HC yet.

[coldknights]

Our small goto nexstar if you touch the scope with a small amount of pressure will move the scope the nut on the inside needs changing it is a lock nut but a elcheapo lock nut works it way loose buy its self and the washer behind it is not the best either.
Will take a few pics and show you which nut ! Also if we tighten the nut up and manually move the scope you can see the nut undo a little each time we move the scope.
This nut is not to be tightened up to much just enough too much will bind the gear to motor.
Hold a spanner on the nut on pic 1 and a spanner on the nut on pic 2 make small adjustments( don't go over board )
We just done it then and made it a lot better will try tomorrow have a sun filter.

[04Stefan07]

I would so love to open it up and tweak a few things to improve stability. The movement of the Sun in my videos is making it hard to process them.

[l3gendluk3]

If you mean if I touch either end of the telescope, no not really, I have to put a small amount of force to move it. There is a small gap between the mount and the female dove connector but i'm too afraid to tighten the screws. I might have a chat with Celestron support.


I'm starting to think that this might be the culprit. I was forced to update my HC and motor boards about a month after first light due to a bootloader error. After it completed I saw a improvement in alignment, tracking and GOTO functions. Unfortunately unless you have the right cable, you will have to buy one for around $50-$60. I got mine from Australian Geographic here (http://shop.australiangeographic.com.au/RS232-Cable-for-Celestron-Computerised-Telescopes-P3367.aspx). You will also need a RS232-USB adapter like this one (http://www.altronics.com.au/index.asp?area=item&id=D2340B). If you got all this your set to go!

I hope this helps,
-Luke

[coldknights]

Make your own Cable for a few dollars the cable in the pic and a RJ22 for the bottom of the hand controller.

[04Stefan07]

Yep I got all those cables already!

[l3gendluk3]

Wow I thought it had logic controllers to handle the conversion. If you had posted this a couple of months ago, you could of saved me $60!

-Luke

[04Stefan07]

I am trying to update the firmware through an XP virtual machine.

I installed the drivers for this serial to usb adapter I got and it can detect the cable but the Celestron software can't.

[coldknights]

Have a read of this link below.

http://www.nexstarsite.com/PCControl.htm

[l3gendluk3]

If I recall correctly, Celestron doesn't like COM ports over 20 (something to do with Java I think) so if your adapter is working at COM20+ you will have to change it. A guide to find out/change the COM port can be found here (http://www.tomshardware.com/forum/159241-45-reassign-ports).

Hope this helps,
-Luke

[04Stefan07]

I will have to try this out! I am a bit scared to open it up though.

[coldknights]

Hi Stefan,
Had a few things to do today ! But will grab the grab and go Celestron Nextar and filter and go outside with it and see how it goes with the sun see if I get better tracking and get back to you in a hour or so.

[04Stefan07]

No worries.

Was just out there and I just had about enough. It is too wobbly to work with! I go to focus my PST and the whole bloody thing shakes and goes out of alignment.

The firmware upgrade did not work at all, it kept saying to turn the hand controller into programming mode which it was in. Now the Sun is missing from the hand controller.

I give up.

[04Stefan07]

Between the mount and tripod head there is a lot of flex.

[04Stefan07]

OK the Sun is back on the controller.

[coldknights]

Does your hand controller version say HC 104 ?
I left it on the sun for 10 mins or so at a time and in that time it only moved a little bit off the center I did a alignment on the sun but had to change the settings in the menu to allow us to do the sun alignment.
Hope this helps was hot out there today at time of day.
Not a good pic I know was a iPhone

[04Stefan07]

Thanks for taking out the scope today! I took mine out again after tweaking with the screws on the mount and it seemed to be locking onto the Sun better but still drifting out of alignment.

My HC says Firmware 4.20 and underneath says 5. something I can't remember.

[coldknights]

That's ok been a while since we looked at the sun (With the correct filters only ) .

How long did it take to drift out of the eyepiece ?

This one we got a 10-20 mins and still in the eyepiece but moved slightly from the Centre of the eye piece.

Can you take a pic of the screws you did up ?
Did you have any nuts to tighten up ?

[michaellxv]

Hi Stefan,

I have the older 80GTL version and had similar problems tracking when I tried. Making sure everything is firm from the ground up helps but in the end the mount is mostly plastic and flexes and moves in the slightest breeze.

Visually mine tracks OK in that an object will stay in the FOV of a 10mm EP even though you can see it moving around that view. I have gone away for 30min and come back to still have planets in the view.

However, putting a camera on it is like putting a 5 or 6mm EP in, the FOV is very small and the drift will take an object out of the view. You can watch the Alt/Az tracking as it moves up then across, gets ahead then waits, gets behind then catches up etc.. The Sun and Moon are large enough that you can let it drift and then watch it come back, with planets you risk losing them. I was always making manual corrections to keep things where I wanted them.

Basically I found it very hard work and gave up having learned the leason that a good mount is required.

Best of luck with it.
Michael.

[04Stefan07]

It's weird after I did this adjustment the second batch of video I captured the Sun stayed aligned. Check out the photos below. I unscrewed them and took that large plastic part off then put it back on.

Also if you look between the orange part and where the mount sits it tends to flex a bit (the part where the mount turns clockwise/anti-clockwise).

Once the object is locked on it either slowly goes out of alignment or slowly goes out of alignment for a bit then stops.

[04Stefan07]

Cheers mate. Would love to get a proper mount one day!

[coldknights]

The nut that needs a small tightening is in pic 1 behind the scope to mount plate can you get to it ?
Can you remove the bolt out of the way ?

[04Stefan07]

Yeah I can take that off. I will give it a go now!

[04Stefan07]

OK it has been tightened.

[coldknights]

Now when you press on the scope with a bit of pressure does it move like before or is the scope harder to move with the same pressure you tried last night ?
Remember not to over do it with that nut do it up a bit check it by putting the scope back on and applying pressure to the scope and see if it is better then before.key word little at a time.
If you tighten it to much it will bind .

[04Stefan07]

That part seems OK. I think it's where the orange part is as shown in the 3rd image.

[coldknights]

I tried rocking our one and not much movement at all in that part.
Seems to be ok .
Does that part look the same thickness all the way around that part?
If it varies then that will make it rock a bit.

Did you change the base or is that the original ?

[michaellxv]

Another option which may work for you is building an EQ wedge for the mount so that you only have to track on one axis. Just google 'slt wedge' for some examples.

I did look at this but with my long tube I would have run into clearance issues. It may be more practical for your PST.

[04Stefan07]

Yeah it looks the same all around.

The base is the same, I just attached it to a new tripod. It behaved the same way on the old tripod as well.