ToUcam advise needed

[Jim]

Hi all
I am now the proud owner of a toUcam and a depreciated bank balance!  Used it for the first time on Mars last week but found the image using my 6" (f8) reflector with nothing in the optical path was too small.   Would buying a barlow help and if so what would be the best power.  Any advice appreciated.

Also any advice on how to manually guide the scope whilst operating the computer and swapping reading glasses......

regards
Jim

[Mike]

Jim,

Nice to see you have finally joined the forum !!

Yes, you will need a Barlow or maybe even a set of them, i.e. a 2x and a 3x so you can stack them. Ian will be your best man to advise you on that as I believe he stacks them.

It is well worth spending the extra money on a decent Barlow, such as the Televue range.

Manually guiding the scope is an artform and unless you've got a good sturdy mount it is very difficult. I can only advise to make sure your mount is as tight and sturdy as possible and oil the moving parts slightly - Polar align the scope as accurately as you can and use a steady hand.

Good luck.

[Jim]

Thks Mike, didn't realise you could stack barlows.  Maybe get a 3x to start with

[Ian]

Hi Jim,

just to add to Mikes comment, I actually use a single 5x powermate when I image planets. That takes the resolution of the camera well beyond that of the theoretical limit of the scope. I used to stack 2 2x barlows, one of dubious quality. The powermate solution suits me well because it fitted well with my eyepiece collection (the shortest focal length I have is 10mm and that rarely gets used). The powermate turns my 15mm plossl into a 3mm plossl without the problems of glueing your eye to the lens due to no eye relief (the formula for a plossl eye relief is 0.73xfocal length).
The downside is they are very costly, but then when you add the cost of 2 quality barlows together, they're probably not much more expensive.
I used to image with my setup before I got my motors and it was a exercise in patience (bit like catching flies with a pair of chopsticks!). I had to position the planet just off the field of view, start capturing as it moved across. Long avis were not possible, and focussing was a trial. However, that said, it was possible and gave me a good grounding to improve my setup and improve my imaging skills.

[ This Message was edited by: Ian on 2003-09-11 20:32 ]

[Whitters]

Jim,
Welcome to the Forum and good luck with the Toucam. The only thing I would add is that try to get your monitor as close to the scope as possible. When I started I had the Monitor pointing thru the conservatory window, then straining my eyes trying to see if the image was anywhere near focus. Don't forget you can use your Toucam on the Moon and if you have a safe Solar filter you can use it to image sunspots too.
Good luck

[Rick]

All this talk of barlows made me wonder.... It sounds a lot as if the webcam's own optics form part of the optical train, presumably taking the place of an eyepiece? Can webcams be used with eyepiece projection, or does that involve stripping them down to bare CCD?

[Ian]

yes, webcams can be used with eyepiece projection, that is projecting an image directly onto the CCD using an eyepiece. In general afocal imaging, with the webcams original lens intact, is not done for several reasons. these include the fact that the adaptors sold for toucams screw into the lens holder and also that the existing lens is very small, very short and not of the quality we're used to using for astronomical observing or photography. It does have one advantage, the original lens has an IR filter built in, if you remove the original lens assembly, there are some good reasons why that filter should be replaced.