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Using a more robust equatorial mount

 

In December 07 I bought an HEQ5 equatorial mount to overcome the power limitations of the Meade mount when loaded with a camera as well as the telescope. I removed the Meade ETX from its own fork mount. That was much easier than I expected. There are just two screws either side which need to be removed and the operation is reversible if necessary. The only difficulty I had was that an imperial Allen key was needed rather than a metric one, but I was able to improvise. The following two photos show where the screws are on the telescope and on the mount. I have replaced the screws on the telescope, simply to avoid losing them.

Screw holes on the Meade ETX125 mount Mounting screws on the side of the ETX125

Here are some photos showing my Meade telescope and Canon camera on the HEQ5 mount:

 

 Camera by itself on the mount

This is how I intended mostly to use the new mount. One of my first results is here. However, the prime focus method looks even more promising - see below.

Canon EOS 5D mounted directly on HEQ5 Canon EOS 5D mounted directly on HEQ5

 Camera piggyback on telescope

The only advantage of this over mounting the camera without the telescope would be if I wanted to use the telescope for guiding. But the drive of the HEQ5 is so steady that I think that will never be necessary, especially with my technique of combining many short exposures through GRIP.

Canon EOS 5D piggyback on Meade ETX125 on HEQ5 mount Canon EOS 5D piggyback on Meade ETX125 on HEQ5 mount

 Camera at prime focus

This was never possible with the ETX drive because it was not steady enough when overloaded. First results with the HEQ5 are far better than I dared hope. See my very first result in this configuration, here. My new possibility of prime focus like this has made me realise that my "astro-process" in GRIP is not ideally suited to telescopic photography, because of the way it does background correction. Therefore I am releasing a new version (8.1.20) of GRIP that significantly improves matters.

Canon EOS 5D at prime focus of Meade ETX125 on HEQ5 mount

 Camera on eyepiece

There would typically be a telescope eyepiece inside the adapter, projecting onto the camera detector.

Canon EOS 5D looking into eyepiece of Meade ETX125 on HEQ5 mount Canon EOS 5D looking into eyepiece of Meade ETX125 on HEQ5 mount  

 Wide angle astrophotography

In summer 2010 I bought a bigger telescope to go on the HEQ5 mount but the mount is still useful for camera-only photos. I use these to make maps of areas of the sky to help me find targets for photography through the new telescope. An example of such a map, with a much wider field of view than the telescope, can be seen here.

It can also be useful for photographing the whole sky with a fish-eye lens.

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