Do I need a pier extension for a GM1000? - Forums

Topic starter

Jul 12, 2025

Hi,

I'm thinking of buying a GM1000.
The largest scope I'm using is a 115/805 with imaging gear, mounted on a Berlebach Planet tripod.

Do you think I'll need the pier extension for the 115mm scope?

Best regards,
Brian

Well Written

Peter Shah (Roboscopes)

Jul 12, 2025

Safer to use a pier extender but you can alter the flip limits on the GM1000 to avoid anything fouling the tripod/mount if needed.

Patrick Wood

Jul 12, 2025 · Edited: Jul 12, 2025

Yes you need the extension. I had to get one after I purchased my mount. Save yourself the shipping cost and purchase it with the mount. My scope is an Esprit 120, 840mm focal length and without it my scope hit the legs aries of my tripod.

Helpful Concise

Detlef Lange

Jul 12, 2025 · Edited: Jul 12, 2025

Hi,
I had a GM1000HPS on a Planet tripot for some time.

I'ld say it depends how long the Apo incl. filterwheell, camera etc. is at the end on the camera side. Could be that it will collide with one of the tripot legs.
The GM1000HPS is quite big. I would start without pier extender and if it then turns out you really need one you can quite good measure the required size and install it later or live with the limitation.

Regards,
Detlef

Concise

Brian

Topic starter

Jul 12, 2025

Thanks for your replies!

At the moment, I have an AM5N mounted on a Berlebach Planet tripod with an EQ6 pier extension.
When I take flats, the telescope is maybe 2 cm away from hitting the tripod.
I don't think anyone can really estimate how that would compare with the GM1000.

I think I'll save the €500 for now and get the mount without the extension.
You can always buy it later, and I have other, shorter optical tubes I can use in the meantime.

Best regards,
Brian

Well Written Respectful

JustinWall

Jul 12, 2025

I have a Tak TSA-120 that required the pier extension. Cringed when paying that for those few inches of lift, but glad I did for mine. Not sure there are any alternatives other then tracking limits as mentioned above.

The GM1000 is a tremendous mount and you will love it!

cs,
Justin

Supportive

FantomoFantomof

Jul 13, 2025

Especially when you use a filterwheel and / or a rotator you definitely need one

Willem Jan Drijfhout

Jul 13, 2025

I have used the GM1000 on a Berlebach planet with a Takahashi TOA-130. A bit longer than the 115/805 that you have. But I definitely needed the extender. And even then, the filterwheel would still crash into the tripod if not careful. So best is to rotate the filterwheel to the top. Looks a bit strange, but safest option. Besides tracking limits beyond meridian, which you can program in the mount, you can also look for an option in your acquisition software to limit altitude to something < 90° if you want to be even more safe.

Helpful Concise

Brian

Topic starter

Jul 13, 2025

Hello,

Thank you very much for your replies.
I bought my GM1000 yesterday.

At the moment, my AM5 is set up on the pier with an EQ6 extension.
The AM5 with the extension is a bit taller than the GM1000.
However, space there is already very limited.
So I will definitely need an extension.

I had hoped to find an adapter that would allow me to mount the GM1000 onto the EQ6 extension.
Unfortunately, I haven’t been able to find anyone who can make such an adapter without requiring me to send parts of the GM1000.
So it will probably end up being the expensive original extension.

I'm also considering which device to get for measuring the environment.
I’ll probably start a separate thread for that.

Thanks again!

Best regards,
Brian

Well Written Respectful Supportive

Patrick Wood

Jul 13, 2025 · Edited: Jul 13, 2025

You have spent a large sum of money on a 10micron which is an excellent precision made piece of equipment. Trying to hobble together miss matched parts to mount it on makes no sense to me. I also doubt you will find someone who is mass producing the adapter you are looking for and will need to find a machine shop to make it for you. Yes the extension is stupidly expensive but as I’m sure you are aware the platform you set your mount on is important too.