Eyepiece projection on ETX-125

I have tried several attempts to do some eyepiece projection photography, but I have never been able to do it with the etx-125, It worked out quite succesfully with Dave Brannigans LX-90.

I have tried 26mm and 13.5mm eyepieces in the adapter, I ensure the eyepiece was fimilarly secured into the adapter, then attached the camera with the T-Mount and put it into the top of the tube.

I had another eyepiece on the back of the scope to get the object into focus.
After I had the object in focus, I tried to get the object in focus in the camera's viewfinder, by altering the focus of the scope and the extending/contracting the adapter but to no avail.

Should I be "plugging" into the back of the tube instead?
What difference does extending and contracting the adapter make?

Also, I'm getting a lot of movement when attaching the camera, will a counterweight dampen this affect and smooth the tracking of the scope with the camera attached? I am considering buying the Scopetronix counterweight.

Any help is greatly appreicated before I throw out the adapter.

Thanks
Darragh

Eyepiece projection is probabily the first way most people take an image through a scope, most eyepiece/camera combinations will give you severe vignetting, scopetronix do specialised eyepieces for this kind of photography, the real advantage here is that you have as many choices in magnification as you do eyepieces. As for not achieving focus, it's hit and miss whether it's going to work on a particular scope/eyepiece/camera combination.

To "plug into the back of the tube" (prime focus photography), you'd need a t-adapter, this is the most common way astrophotographers work it
If you have a SCT, if you extend the tube you effectively increasing the magnification, and lowering it by shortening the tube, but normally this is a fixed length, you focus here by focusing the scope in the normal fashion.

As for movement, what exactly do you mean by movement, is it in the link between the adapter and eyepiece or is a mount clutch slipping? Balancing the OTA is important for motor/gear wear it also help prevent the mount from slipping.

Darragh,

Some questions...
Have you tried ignoring the adaptor and just holding the camera concentric with the eyepiece? This will even work with a camera phone! Just make sure the telescope is focused for visual observing first. The adaptor just eliminates stray light and ensures the concentricity of the setup. Once you have the purely manual setup working then try the adaptor.

Is the adaptor the type of one that you put the eyepiece into? If it is then it will be moved further away from the focus point of the 'scope. This along with the longer light path when using the diagonal mirror might be your problem in ataining focus. Try swaping the adaptor to the straight through eyepiece position.

Hope this helps. Plenty of opportunity to test it on the Moon these clear nights.

Darragh,

The rear port is generally used for prime focus photography - you're correct in using the eyepiece port for eyepiece projection photography. You appear to be doing everything right, the procedure being:
Use an eyepiece ranging from about 26mm to 13mm (maybe up to 10mm for lunar closeups).
Insert the adapter with eyepiece into the eyepiece port and attach the T-ring/camera.
As your adapter is a variable one, loosen the screws and set it to the shortest distance initially.
Centre the object in your finderscope. It should be visible in your viewfinder as well.
Loosen the adapter screws and pull the camera up until the optimum magnification (not necessarily maximum) is obtained. Keep the object centred as the balance of the scope will shift.
Focus. This is the most difficult part and could take some time.

Are you anywhere near focus? As an aid, you could try the Kendrick Kwik Focus for the ETX 125.

Regarding counter balance weights, are you referring to the Scopetronix piggyback bracket with weights as I don't see any other one? If so, can't see these will be of any use when the camera is in one of the ports. I've a JMI weight which screws on underneath my ETX. However, the best counter balance set up for the ETX is probably Astro Engineering's counter balance weight set and accessory plate - refer www.astro-engineering.com/ETX/etx90105125.html (click counterbalance in section contents).