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View Full Version here: : Possible to use Toucam as high sensitive viewer like GSTAR???


davewaldo
18-07-2007, 12:45 PM
Hi Everyone.

I was wondering if it would be possible to use a Toucam with the long exposure mod to view faint objects with better detail. I'm not talking about taking great photos, I'm just wondering if I could use it to bring out some details of faint nebulae whilst out in the field.

Basically I want to use it conected to a laptop, viewing through my 10" Dob, expose for a second or two, and be able to view an "image" of say the sombrero Galaxy in better detail then I could viewing through the eyepiece.

Or even in similar detail, as it would help show friends the object when they are not used to viewing through a scope.

It is my understanding that this is one way of using a GSTAR. I have no idea whether it would work with a toucam.

Am I hoping for way too much?

Cheers,

Dave.

ballaratdragons
18-07-2007, 02:33 PM
In a nutshell . . . Yep.

The Standard Toucam isn't sensitive enough to give detail on fainter objects. It only has a lux rating of <1.
Many Stars will show up, but not all of them.

The Modified Toucam still will not give the 'G-Star' look. Again due to the high Lux rating. You can get great detail if you expose for about 30 - 200 seconds, but that isn't exactly the 'Live' show you are after.

If you can live with having an image update itself every 30 - 200 seconds IN COLOUR then go for it. :thumbsup: The onscreen images are great.

davewaldo
18-07-2007, 02:41 PM
Thanks very much...

This is basically what I was expecting... so as my Dob doesn't track I will not be able to expose for long enough without getting trailing. :(

Oh well... I guess I will just have to start tracking.... :sadeyes:

ballaratdragons
18-07-2007, 02:55 PM
Yeah Dave, you would need to track an object for Deep Sky with a Toucam.

They do give a great cloloured on-screen image if you are prepared to wait for the exposure to be taken.

You just set the capture program (I use 'Desire' coz it's the easiest) to the required exposure eg: 60 seconds, then in 'number of exposures' you can type in any number up to 10,000 if you want and it will automatically send a new image every 60 seconds (or whatever exposure length you put in).

ballaratdragons
18-07-2007, 02:59 PM
To give you an example of what you would see at every update, here are 2 raw (bmp) on-screen images taken at 90 seconds.

No stacking, no processing, just the single raws (bmp's) as you would see them.

The Trifid is without an IR filter, Carina is with an IR Filter.

davewaldo
18-07-2007, 03:10 PM
WOW! I thought that it would require a load of processing to get to that stage!

So once I do have tracking this method would be a great way to explore the skies! I would be more than happy to wait 60secs for images like those! :)

Thats awesome! I love viewing naturally through the EP, but I often wonder what the object would look like if my eye could just "soak up a bit more light".

Thanks for posting Ken!

wavelandscott
18-07-2007, 04:02 PM
I am sure that others can chime in that actually have experience but wouldn't a tracking platform allow you to track sufficiently to get what you are after?

Just a passing thought...

ballaratdragons
18-07-2007, 04:12 PM
It is fairly hard to get round stars on a Tracking Platform, but yes, it should work to a point. As long as there is no wind, and it tracks accurately. The longer the exposure the more critical, obviously.

davewaldo
18-07-2007, 04:53 PM
hmmm... you've got me thinking...

You say a 30sec or 60sec exposure would be good. What f ratio would that be for? I'm assuming one could get a usable image quicker with an f5 scope than one could with an f12 scope?

ballaratdragons
18-07-2007, 05:41 PM
Apature is a factor, as is Focal length. Depends on the object.

For example: My 12" dob (f5) will not give nice wider images like my ED80 (f7.5) becuse of focal length. So it isn't as cut and dry as 'focal ratios'. There are some maths involved to solve what focal ratio for what object.

My images above are using the ED80.

bojan
18-07-2007, 05:54 PM
Focal ratio is important for "spread" objects (spread over number of pixels), like nebulae, Moon etc.
Aperture is important for point-like objects, like stars [and planets if image fits into one (or two) pixels only].