toucam question

[ving]

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? :confuse3:

[ving]

no one got a toucam they can test for me and get back then?

[Merlin66]

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.

[[1ponders]]

If I were you ving I'd be thinking about a minatron or small SAC camera

[ving]

whys that paul?

[iceman]

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..?

[ving]

oh yeah, it'd go in my 8" f/6 newt...

[Dennis]

Hi Ving

A bit of a ramble follows.

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.

Cheers

Dennis

[ving]

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. :)

[davidpretorius]

what part of the sky mate, say the coal sack at 208x magnification, there are some mag 6 stars there, would that help get you close to an answer

or is there a nice bunch of varying magnitude stars close together that will tell you better. Weather looks good here, so i could try tonight

[Dennis]

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

[ving]

star from mag6 and work your way down i guess dave... see how low your can get. also apart from imaging, on screen what mag stars'll show?

[ving]

i guess idealy one could take shorter exposures and stack them then?

[Dennis]

Hi Ving

Here are the doubles and the exposures used to capture them.

Rigil Kentaurus & Acrux: Exp 0.25 secs. Approx 20 frames combined.
Theta 1 Ori: Exp 2.8 secs. 12 frames combined. Dark Frames used.
Antares: Exp 0.5 secs. Approx 20 frames combined.

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.

Equipment Used: Vixen ED102mm f9 refractor, TeleVue x5 PowerMate, Vixen x2 Barlow, Meade LPI CMOS digital camera.

Cheers

Dennis

[davidpretorius]

based around a non tracking sytem??

[ving]

I have a ra drive dave, i dont always use it but i prolly will for this.

[[1ponders]]

How's your polar alignment ving ;)

[ving]

not too bad paul, yours?

[acropolite]

:lol2:@ ving. I can vouch for hot pixels on the LPI, but you can subtract them out with dark frames.

[ballaratdragons]

Vingo,

this is the trap using the Toucam without using the Long Exposure Mod feature.

Yep the focus is all over the place, but you can see some pretty faint stars in there!!! You'll have to look up the mags of each.

No Tracking, and 12" dob. Just 12 seconds of video as it moved across the EP, then stacked in Registax.

Hope that helps

[ballaratdragons]

Again Unmodded, and this one has G & H.

That faint enough for you?

Yeah, I know the photo is atrocious, but it was my first attempt at using a Toucam :lol:

[asimov]

I've seen 'the pup' on the laptop screen (without imaging it I mean) which is mag. 8.4 with the unmodded toucam & the 6" refractor.

[[1ponders]]

This is why I was suggesting the Mintron ving

http://www.iceinspace.com.au/forum/showthread.php?t=3358&highlight=Mintron

Have a look around the site there are a number of images taken with the Mintron. Check out that Omega Centauri for going deep, that Tony took

[ballaratdragons]

or if you want another option, how about a camera that picks up .00002 lux!

http://www.myastroshop.com.au/guides/gstar.htm

[Karls48]

Hi ving
I would recommend GEM B/W camera for about $370 from http://www.allthings.com.au/Catalogue/CCS/gem%20monochrome%20low%20light%20cc tv%20dsp%20video%20camera.html (http://www.allthings.com.au/Catalogue/CCS/gem%20monochrome%20low%20light%20cc tv%20dsp%20video%20camera.html)
Attached are images of Alfa Centauri and Canopus, taken with 135mm Telephoto lens, 100 exposures. No tracking, I use AstroVideo software that stacks the images on fly, as long the selected star remain in view. Please note that original image in FIT format show more detail, but they are big, 1.6 Mbyte.

file:///A:/2006-04-26-224-sum-001.jpg



Karl

[33South]

Ving Ive got an LPI you are welcome to borrow to see if does the job. (PM me)

I dont plan on using it any more (got a GSTAR-Ex) but want to keep it to include if/when I decided to sell the LX90.

[ving]

hiya karl, I am looking in the price range of toucam and lpi. you camera is great but just a tad too expensive for me...

hi chris, thanks for the offer. i may jsut take you up on it. I am busy for the next couple of weekends tho so I might try for about 3 weeks from now (if that ok). :)

[33South]

No probs, just pm me when ready.

[ving]

dave?

[davidpretorius]

no go here yet, dave, clouds clouds clouds and oh yes clouds.

weather is looking alright for tonight though