Do telescope camera adapters need special lenses?

Question

Indoors it works without any lenses, but it won't focus enough when using a lens, viewing stars and planets. I've tried a few combinations of the various parts but nothing works. I paid £40 for it and the shop wasn't helpful so I've not asked again for advice.
Helios 200mm Explorer, Centon SLR.

gjmb1960 - that's the same as what worked with mine but only indoors. Even outdoors though, the magnification is reduced a lot.

planke12 - The Barlow lens is about the only thing I haven't tried, it does fit onto the camera and obviously onto the scope. The camera is an SLR, not a webcam. Quite heavy. But still, the magnification won't be much and the planets are small enough with proper lenses.

Answer 1

What are you trying to photograph?

The setup that works indoors is *optically* correct, but I suspect that the problem is with exposure, not focusing. Astronomical objects are generally quite dim, so you will probably need a time exposure to get a good image, and that means you need a clock drive and (probably) a guider as well.

If you don't have that and don't want to buy it, just snap pics of the Moon, which should come out even with short exposure times.

Answer 2

I'm not sure what sort of adaptor you've got. A T-mount works without any lenses and you focus the objective directly onto the film. Most focusers don't have enough travel, so the primary mirror needs to be moved up the tube. If you've got an eyepiece projection adaptor you may need to move the camera further away with an extension tube, or you could try a barlow lens, as has already been suggested.



I've just noticed that your 'scope has a "Direct SLR Camera Connection" - could that be part of the problem?

Answer 3

You can purchase something called an "Eye Projection" which helps to couple the webcam to the eyepiece without removing its lenses. The Eye piece projection is specifically designed to hold the lenses in place while mounting the camera.

Infact using a barlow along with the eyepiece and the webcam lense might provide a better picture in contrast to simply mounting the CCD chip directly in lieu of the eye piece.

Hope that helps !!!!

Answer 4

I put a webcam without any lense on my newton telescope
that worked better than with a lense

( i removed the lense from the webcam, removed the objective fom the telescope, and put the webcam in place of the objective )