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View Full Version here: : Imaging using the Meade LS?


AvronW
13-12-2010, 11:29 AM
I know it is not the ideal platform, nor intended for serioud imaging, but as a way of introducing my kids to astronomy, it is the platform we have.

Does anyone have any experience with or knowledge on:
1. More detail info on using the telescope's own ECLIPS camera to do stacked exposures? The menu info is really scant, so hopefully someone else has messed with this and can give some clues.
2. Anyone tried or know if the LS-6 can sustain the weight of a piggyback mounted DSLR, without doing the drives any damage?

Thanks,
Avron
:question:

jenchris
13-12-2010, 11:49 AM
Knowing engineering a bit, I can suggest mounting the DSLR and balancing the OTA with some weights if possible.
It's never going to be a great platform - but keeping the rig tremble free and not on a deck for instance will help.
If you're going to be dong a lot of piggyback stuff, I'd suggest getting a scope with steel gears, I think the LS is equipped with nylon gears.
A single fork arm is prone to vibration and too much weight on the bearings will make it lumpy I'd guess.

AndrewJ
13-12-2010, 01:06 PM
Gday Avron

The Eclipse camera is pretty much useless for doing pretty piccies as it doesnt shoot through the scope, its just a very wide angle webcam,
and as such has very little fine detail.
You can do multiple exposures if required, but you would have to run each shot manually and save to the SD card as you went
( of if you have a graphics card with capture facility, you can do grabs direct from the composite video feed out. )
As to "gearing", the LS setup is very robust, and will easily hold the weight without damage. The gears are all metal, and the motor unit is similar to that used in the LX200s ( ie a proper gearhead motor )
However, three drawbacks.
1) The fork arm bearings are very close together, and hence dont provide a very stable mount as the load goes up. I doubt it would break, but it will probably flex, and when it flexes, it affects clutch preload.
2) There is no user adjustable clutch, and hence no means to do balancing. I mounted a Meade microfocusser, 2"diagonal and binoviewer on the rear of mine and the DEC clutch actually started "oozing",
thus losing alignment. You need to test under load to see what happens.
3) There are no tapped holes in the OTA casting to mount any brackets or rails. Balancing may not be required for just a DSLR, hanging off the back,
however, to do a piggyback load, you may have to remove the reddot finder and use its bracket, but you also need to be careful as excess metal on top of the scope appears to affect the Nth sensor.
Also, as there are no tapped holes, the LS has no provision for mounting weight rails etc,
( and if you used an underneath rail, it blocks the camera ).
You could probably wire a weight to the tube support arm in a pinch,
but its not very elegant or adjustable.

Andrew

AvronW
14-12-2010, 11:57 AM
Thank you for the advice. I'll give the DSLR a cautious try and let the kids do some stacked images using the ECLIPS cam, which as you point out is really just a webcam, but should be good to get the kids started.

AndrewJ
14-12-2010, 12:28 PM
Gday Avron

No real need for caution, it wont break:thumbsup:
All i suggest is when you have figured out how to load the DSLR to your scope, just get it tracking and watch for drift in the alt axis.

Also, you could look at a cheap webcam like the Meade LPI as an entry level camera. They are pretty cheap now, and all the software to run them is free. They allow longer exposures and shoot through the scope, so give you much more options to keep the kids interested.

Andrew

jenchris
14-12-2010, 12:47 PM
Thanks for the correction Andrew J - I wasn't sure of the configuration of the LS as per the insides..
I have to say though that single arm forks are really not going to be easy to use well with extra load on.

AndrewJ
14-12-2010, 11:00 PM
Gday Jennifer

I have added a few piccies of the drives from an LS.
The DEC clutch is actually a rubber gasket between the worm wheel and the backing plate. The RA is totally dry.
The outer alloy plate in the DEC is what preloads the bearings and clutch,
and orthogonality is controlled by the marked grubscrew.
As i mentioned earlier, it wont break or fall apart,
but its definitely not a rigid mounting for heavier loads.
I also added a piccy showing the scope with focusser and binos.
In this setup, the DEC clutch actually "oozed" at a rate that was clearly visible in the EP.

Andrew

jenchris
14-12-2010, 11:34 PM
Thanks for that - about the only thing that looks robust is the pivot screw