in my quest for an astrometry tool for measuring double star separation and position angle, merlin sugested a program for CCDs called reduc... so theres the background of the question so you know why i am interested in the answer.
now the question is: what magnitude can an unmodded toucam image down to?
Good question... don't know. I try to find out at the weekend, but with a max
exposure of only 1/15 sec I don't think you'll get very far....maybe Sirius??
Obviously far better with an SC1 Mod version.
With low gain the ToUcam can easily get the 6 main trap stars in Orion. With higher gain, you might be able to get others as well. I don't know what mag they are, but you could look it up.
I'd think you could get up to mag 7 o 8 for point sources..?
I have used the Meade LPI (16 second maximum) to image some double stars. However, to capture those with a smaller separation angle, you need to start using Barlow’s, thus getting into multi-second exposures, which are problematic in bad seeing. Also, anything over 3 or 4 seconds with the LPI produced quite a few hot pixels, which appear as red, blue or green noise specks in the image.
The best results I have had are with my SBIG ST7E which is cooled, but obviously completely out of the question for what you want due to cost.
I have also used the Orion Star Shoot Deep Space Imager, but at $579 from Sirius Optics that too is also expensive.
Good luck with the project, it sounds fun...and challenging.
so an LPI will do up to 16secs hey... maybe the lpi is for me then.
thanks dennis
7-8 mag with the toucam.... argh! maybe thats enough for the brighter doubles.
well atleast it gives me something to think about.
Just to reiterate so your expectations are not dashed.....expect noise and horrible looking images at 16 seconds, due to lack of cooling. Might be slightly better in winter when it's 0 deg outside though? Also, don't forget the strain on your tracking system if using Barlow’s.
The doubles I grabbed with the LPI were using my Vixen 4” f9 refractor and a Vixen GPDX mount, which is quite a good, steady combination for wide-ish doubles.
Just to reiterate so your expectations are not dashed.....expect noise and horrible looking images at 16 seconds, due to lack of cooling. Might be slightly better in winter when it's 0 deg outside though? Also, don't forget the strain on your tracking system if using Barlow’s.
The doubles I grabbed with the LPI were using my Vixen 4” f9 refractor and a Vixen GPDX mount, which is quite a good, steady combination for wide-ish doubles.
Cheers
Dennis
i guess idealy one could take shorter exposures and stack them then?
Rigil Kentaurus and Acrux were captured using Vixen x2 Barlow.
Theta 1 Ori was captured using Televue x5 PowerMate.
Antares was captured using Televue x5 PowerMate and Vixen x2 Barlow stacked.
Note the use of dark frames with Theta 1 Ori (Trapezium) and the atmospheric smearing.
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@ ving. I can vouch for hot pixels on the LPI, but you can subtract them out with dark frames.
