Is it possible to use a german EQ mount in Alt-az "mode"?

[pgc hunter]

Would it be possible to use a GEM as an alt-az of sorts, when setup in a way similar to the picture below? Seems like it could work if balanced properly.

[gary]

Originally Posted by pgc hunter

Would it be possible to use a GEM as an alt-az of sorts, when setup in a way similar to the picture below? Seems like it could work if balanced properly.

Hi Peter,

Your mount as shown is not just an Alt/Az mount "of sorts", it is an Alt-Az mount.

This question is similar to asking, "if I were to take my GEM, as shown, to the
geographic North or South Poles on Earth, would it still work?" and the answer is "yes".

In fact your Alt/az configuration is identical to an equatorial mount configured
for observing from one of the Earth's Poles.

It will therefore act as Alt/Az mount at your existing latitude in Victoria.

I trust this was the response you were seeking?

Best Regards

Gary

[Dennis]

I tried this with my Vixen GPDX German Equatorial Mount but unfortunately, the Latitude range of movement did not have enough, ahem, latitude!

I could not set the mount to 0 degrees (as if on the Equator) and when I set it to 90 degrees (as at the Poles) the balance was a bit dodgy with a heavy OTA.

Cheers

Dennis

[pgc hunter]

Originally Posted by gary

Hi Peter,

Your mount as shown is not just an Alt/Az mount "of sorts", it is an Alt-Az mount.

This question is similar to asking, "if I were to take my GEM, as shown, to the
geographic North or South Poles on Earth, would it still work?" and the answer is "yes".

In fact your Alt/az configuration is identical to an equatorial mount configured
for observing from one of the Earth's Poles.

It will therefore act as Alt/Az mount at your existing latitude in Victoria.

I trust this was the response you were seeking?

Best Regards

Gary

thanks for the explanation, although my name is not Peter! So basically it does work. With the arrangement shown in the pic, all one would have to do is lock the RA axis and then it's all set. The Dec axis has a 360º travel so it can cover all elevations.

[gary]

Originally Posted by pgc hunter

thanks for the explanation, although my name is not Peter!

My apologies. I had glanced at the bottom of your post but now see that the
name 'Peter' is simply associated with your quote from a cartoon character.

So basically it does work. With the arrangement shown in the pic, all one would have to do is lock the RA axis and then it's all set. The Dec axis has a 360º travel so it can cover all elevations.

Any balance issues aside, you indeed have one perfectly usable Alt/Az mount.
In fact, many Alt/Az mounts, such as Dobs, can't allow the OTA to "flip" beyond the
zenith position. However, your's can and you can make use of the complete
180 degrees of play in the Alt axis if you so choose.

Equatorial mounts are really just Alt/Az mounts tilted in elevation so as the
Az axis can then correspond to the polar axis.

Best Regards

Gary

[gary]

Originally Posted by pgc hunter

thanks for the explanation, although my name is not Peter!

My apologies. I had glanced at the bottom of your post but now see that the
name 'Peter' is simply associated with your quote from a cartoon character.

So I'm not quite sure what your name is?

So basically it does work. With the arrangement shown in the pic, all one would have to do is lock the RA axis and then it's all set. The Dec axis has a 360º travel so it can cover all elevations.

Any balance issues aside, you indeed have one perfectly usable Alt/Az mount.
In fact, many Alt/Az mounts, such as Dobs, can't allow the OTA to "flip" beyond the
zenith position. However, your's can and you can make use of the complete
180 degrees of play in the Alt axis if you so choose.

Equatorial mounts are really just Alt/Az mounts tilted in elevation so as the
Az axis can then correspond to the polar axis.

Best Regards

Gary

[netwolf]

The older Vixen polaris mount that also came with Celestron SC8's, can be used in Alt/Az mode. Few EQ mounts allow there RA axis to be set to 90degrees, this is the requirement for Alt/Az use. The RA axis will become your Az axis and your Dec will become your Alt. The other thing to consider is weather your drive electronics or Goto controller will work in this mode.

[Dennis]

Hi Fahim

Yes – I saw some on-line photos of the venerable Vixen SP and SPDX mounts that could be configured for alt-az operation, but the later GP and GPDX did not have that range of adjustment unfortunately!

Cheers

Dennis

[IanT]

Hello
I have an old Vixen Polaris, configured for Alt-Az and used with a 4" refractor. It's great for getting up and going to the great outdoors. The mount is sturdy and smooth but needed new legs on the tripod because the original Vixen legs were too short for refractors and middle-aged men.