For several years, I have been using a piggyback setup with a small scope (e.g., 80mm) on top of a C11" EdgeHD in an observatory. I am going to replace my current small scope with another brand around the same size. So, I was contemplating perhaps going to a side-by-side design, mainly due to so many wires and accessories being crammed together and making it difficult to remove the scope if it needs repairs. I understand the balancing of a side-by-side can be tricky. Perhaps there is no real advantage of one design over the other. However, I am just curious to hear from folks who have done both as to which design they prefer and why.
Piggyback vs. Side-by-Side Design
Well Written Engaging
Side-by-side saves on counterweight, costs less potentially and it is easier to mount and dismount scopes in and out. Flip side is that a 3-step balancing act is required. I use both.
1. I've used both, and in my case I had a side by side bar, but when screwed tight the scopes were not looking quite at the same thing. Piggy back using a Skywatcher Guidescope mount allows me to adjust the top scope in both directions.
2. With side by side I found the scope - depending on it's altitude was more likely to hit the tripod/pier plate much sooner than if mounted piggy back.
These comments are without mentioning any balancing issue.
2. With side by side I found the scope - depending on it's altitude was more likely to hit the tripod/pier plate much sooner than if mounted piggy back.
These comments are without mentioning any balancing issue.
andrea tasselli:
Side-by-side saves on counterweight, costs less potentially and it is easier to mount and dismount scopes in and out. Flip side is that a 3-step balancing act is required. I use both.
I've heard the 3-step balancing act can be a bit tricky; I guess until you learn it like anything else
Carastro:
1. I've used both, and in my case I had a side by side bar, but when screwed tight the scopes were not looking quite at the same thing. Piggy back using a Skywatcher Guidescope mount allows me to adjust the top scope in both directions.
2. With side by side I found the scope - depending on it's altitude was more likely to hit the tripod/pier plate much sooner than if mounted piggy back.
These comments are without mentioning any balancing issue.
Hitting the tripod/pier plate is something I thought about, so I'm glad you mentioned it.
I also have to park my scope in the Park 4 position as I have a roll-off-roof, not a dome. I'm not sure how that would be affected by a side by side mounting plate.
Bruce Donzanti:
I also have to park my scope in the Park 4 position as I have a roll-off-roof, not a dome. I'm not sure how that would be affected by a side by side mounting plate.
If it is in the horizontal position, which I expect it to be for a ror obs, then the trick is to arrange everything so the longest arm, the one with the smaller scope, points to the top. In my several years of using dual sided mounting I had never issue with hitting the tripod.
Bruce,
Over the years, I've addressed the mechanics of telescope mounting in a number of talks that I've presented. An imaging system is inherently more stable when it has a high resonant frequency and the best way to accomplish that is to keep the mass as close to the RA axis as you can get it. That configuration also reduces the torque needed to drive the mount. Placing multiple telescopes side-by-side is the best way to keep the mass "low" on the mount. Here are a couple of relavant slides.
John
Over the years, I've addressed the mechanics of telescope mounting in a number of talks that I've presented. An imaging system is inherently more stable when it has a high resonant frequency and the best way to accomplish that is to keep the mass as close to the RA axis as you can get it. That configuration also reduces the torque needed to drive the mount. Placing multiple telescopes side-by-side is the best way to keep the mass "low" on the mount. Here are a couple of relavant slides.
John
Helpful Insightful
Or you could buy an Avalon mount…
John Hayes:
Bruce,
Over the years, I've addressed the mechanics of telescope mounting in a number of talks that I've presented. An imaging system is inherently more stable when it has a high resonant frequency and the best way to accomplish that is to keep the mass as close to the RA axis as you can get it. That configuration also reduces the torque needed to drive the mount. Placing multiple telescopes side-by-side is the best way to keep the mass "low" on the mount. Here are a couple of relavant slides.
John
Thanks, John, as always. Unfortunately for me, based on my observatory design which is built on top of my 4-car garage, I need to mount multiple scopes or it becomes a nightmare to swap them (a long story as to why). OK- I'll need to reevaluate how I redesign things based on the suggests here.
Side by side. Lower polar moment of inertia.
