Guidecam Question

[mtodman (Matt)]

I have been guiding with a Meade DSI 2 Pro (mono) for a while with reasonable results however in my quest to improve autoguiding, I'm considering upgrading to an SX Lodestar. Does anyone have any comments / ideas on whether I would notice an improvement in guiding with the Lodestar (as opposed to the DSI)? I'd be interested in other's opinions.

Cheers

Matt

[tlgerdes (Trevor)]

I think Marc Aragnou uses a Lodestar now.

What specifically are you trying to improve over your DSI?

[mtodman (Matt)]

Hi Trevor,
I guess I'm trying to determine if a reduction in noise / increase in sensativity, etc produces better guiding results.
For example, if I had 2 identical setups with the only difference being the guidecam (one using the DSI & the other using a Lodestar), would I achieve better guiding results on the Lodestar assuming the same guide star was being used?

[multiweb (Marc)]

The lodestar is more sensitive so you can pick fainter stars at a higher frame rate. Suited for an AO. Other than that if you guide let's say 1,2 or 3s any will do. You won't get any improvement in your guiding for using a lodestar. Unless the guide star is very faint or you use an OAG and have trouble finding one I wouldn't bother. They're pricy.

[tlgerdes (Trevor)]

1) the Lodestar with its better sensitivity will probably give more stars to guide on.

2) If the DSI can find you lots of guide stars, then I dont believe a lodestar from its sensitivity side of things is going to improve you a great deal.

People use alot of simple setups to autoguide very successfully. Again it comes back to what are you trying to improve with your autoguiding?

I use a SSAG on an 80mm f5 refractor, don't have trouble finding guidestars, even 1 pixel dots of light are fine. Seeing seems to play a more signifcant part in autoguiding, with the answer there being longer subs for guiding to average out the effects of seeing.

[tlgerdes (Trevor)]

Just checking the specs ,the DSI II Pro and the Lodestar use the same CCD, the Sony ICX429. The DSI uses the 429ALL variant compared to the Lodestars 429AL.

I would say the sensitivity of both would be very similar as well based on that.

The difference then would only be the inbuilt guideport.

[ballaratdragons (Ken)]

Actually, the camera plays only a small part in autoguiding.

If a camera (whichever camera) can see a star, then it's up to the guiding program to lock onto it and stick with it.

I have autoguided with a Toucam (still do) modified and unmodified versions, DSI-1c, an unknown brand el-cheapo planetary cam, and I even tried my Samsung Deep Sky broadcast camera.

They all shows stars of varying quality, but they all worked fine as the Guiding Program was able to lock onto a star in all of them.
The only time I have had guiding problems is when the 'program' goes wrong, not the camera.
The program I used to use was Guide-Dog, but it was a bit troublesome at times. Now I prefer to use Guidemaster and it locks onto whatever star you want.
I've even used a tiny faint Globular Cluster as a guide star with perfect guiding results

But in short, the DSI you have is excellent for guiding. Maybe you need to use a different guiding program, or tweak the one you have.

Also check your mount for backlash.