Webcam with planets

[Taff]

Hi' can anyone help me out.I'm fine while takeing captures of the moon,but when look through a 7.5 EP on a planet then put a webcam to the scope and focus in all i get is a blank screen on the laptop Thanks.Mark

[brianb]

when look through a 7.5 EP on a planet then put a webcam to the scope and focus in all i get is a blank screen on the laptop

It's awkward. If the planet is way out of focus, it might be on the chip & still invisible - did you try winding the gain right up?

The best way I've found is to align the finder very carefully - with the web cam in the scope, navigate to an easily recognised feature (Plato is a good one) and line the finder up as carefully as you can. Then you should be able to aim at the planet using the finder & have it somewhere on the webcam chip. This method works for me using a 2,800 mm focal length scope and a 3x barlow with the DMK21 camera, which has the same size chip as most webcams, with the assistance of a perfectly ordinary 9x50 finder scope.

[Taff]

Thanks Brian' for your help.I will try that way next time.Mark

[Psychobilly]

It may also help if you make the webcam and the 7.5mm EP parafocal...

Pop the EP in and focus on a distant terestrial target...

Repalce it with the webcam and adjust focus for a sharp image...

Remove the webcam and slide the EP back into the focuser whilst lookign through it..

When the EP comes into focus put a mark on the push fit barrel.. wrap some insulating tape around the barrel above the mark so that teh EP only goes into the focuser as far as the tape line... Another option is to make rings from an old 35mm film canister...

When you want to use the webcam ... center and focus with this "parafocal EP" then pop it out an put the webcam back in and you should be fairly close to focus...

Peter...

[beamish]

Another XLNT tip from the "Meister "

[Space Cowboy]

Great idea!

[michael.h.f.wilkinson]

Depending on your telescope, you could get a flip mirror (I have a Vixen which works fine). This is like a retractable diagonal mirror, in which you put the EP in the right-angle output, and the webcam with a suitable Barlow/EP projection set-up in the "straight ahead" port, such that it is parfocal with the EP. In this case lowering the mirror and centering the object in the EP, followed by flipping up the mirror is sufficient to get the planets in the field of view.

Mine cost about EUR 90, but it was so worth the investment. The method should works on SCTs, Maks, RCs and refractors, but may be problematic on Newtonians (focus may not extend far enough).

Hope this helps.