2 DSI cameras or LPI's working sametime for guiding?

[EzyStyles]

Hi Guys,

I'm a little confused. Ive seen alot of people using a DSI for imaging and LPI for guiding but wouldn't you get conflicts running two copies of Envisage at the sametime? or you guys have two computers?

Cheers.

[xelasnave]

its a two of everything world thats for sure... I look forward to hearing the poss as this also has been on my mind
alex

[alandee]

Works a treat, but only one copy of envisage, it just opens a new tab ie dsi1 & DSI2 or DSI1 & LPI, then you can use one for autoguide and one for imaging, change the sample rate for the imaging to the fastest with clarity and the imaging camera tab you use as normal. You can run up to 19 DSI's I think and one LPI from Envisage ( you might need a supercomputer to cope however :P )

[EzyStyles]

arh thanks Al! Ive successfully connected my autoguiding port with Envisage via the shoestring adapter. How do i autoguide and track? does it have to be a bright star in order to work?

Don't get the buttons will i be using them all?

Track Here
Track Last
Will Cal
Center Target
Set Target
FL in mm
Corr Gain?

cheers

[alandee]

When you draw your two boxes ( I usually use one around the item being imaged or a corner star if you can get a fast exposure rate and still see the star and then the second around a convenient star in the opposite or far corner ) it will de-rotate as it stacks if it needs to. then pressing guide here will try and keep the first box item in the same position.

Centre target will try and centre the first box item in the fov, but I don't find it very effective, and can't really see the point.

Set target will let you draw a single box around an item and attempt to keep that in the same spot once you press track here.
FL in mm is more for the fits header I think, I've changed it and it makes no obvious difference on my setup.

Corr Gain I have only played with a bit, with 2 cam's it is a little redundant, because you set the tracking / guide cam as low exposure ( quick screen refreshes ) but if you are using a longer exposure, you can increase the corr gain to help it get closer to the target it is trying to centre ( does that make sense ?) ( ie. it will move the scope a little more depending on the figure in corr gain to try and reach the target spot )

So basically, the image coming in on the device used for tracking you want as quick an exposure as possible so it can adjust your tracking as accurately as possible. So a bright star is better, but not essential. The image of the guide star doesn't have to be great, just good enough to always see the star and it's shape while keeping the exposure time as low as possible. My understanding is that as the image is processed in envisage and the change between the track here target and it's latest screen refresh determines how much and in which direction it moves the scope.
Draw a couple of boxes at opposing sides and press track here. Job Done !

One last thing to consider is the orientation of your camera in the scope. I mounted my guide cam in the wrong orientation, and as envisage tried to track, it was moving the scope the wrong way .. took me a while to work that one out, but I'm getting old :P

[EzyStyles]

Many thanks for your informed post and answers. I have copied your reply as a reference :)

I'll give it a go once I get myself a guidescope.


Cheers Al.