Quick Polar Alignment for the Paramount ME

 

 

 

 

The fastest way to align a Paramount ME is to skip the alignment step!]

 

My environment in Florida is nightly equipment moves to the end of the driveway from the garage. That is, I must move equipment, re-setup and re-align every night.  Supporting my Paramount ME is a Monolith Portable Pier which rides on JMI Wheely Bars.

 

A working Procedure:

My biggest frustration with the Paramount ME was my inability to rapidly setup and achieve a good polar alignment each night.  Using the Takahashi NJP mount with its internal polar alignment scope I am usually able to accomplish these tasks in 10-15 minutes.  With the ME it was taking 90 or more minutes every night.  To be fair the ME is carrying much more weight which the NJP would not support.  Also the focal length of the Takahashi FRC-300 atop the ME is 2348mm vs. 1000mm for the TOA-130 on the NJP.  This makes the nightly ME alignment process relatively much more difficult.  However, this procedure has worked well on focal length telesocpes of over 3500mm.

 

After months of unsuccessful trial and error, I have finally found a setup procedure for the ME that gets the setup done in less time than the NJP.  Here is my procedure:

 

  1. Step-0 is to do a good, full setup of the Paramount ME mount.  (this now means on top of Pier-Paws, see below) First, permanently fix the heights of all 3 wheely-bar height adjusters and then lift the mount onto Pier Paws.  This includes physically locating the tripod supports (height adjusters) on the JMI wheely-bar in a fixed spot on the driveway.  I then accurately level the Paramount ME in all directions.  I establish a very good polar alignment using the Quick-setup procedure from Software Bisque.  After this I make 2 or even 3 T-Point model runs of 20+ points.  After each run I refine the polar alignment and start over.  After I have a good polar alignment (usually under 120 seconds of error) I do a T-Point run of over 100 points.  This model is saved for future use on subsequent nights.  This entire procedure normally takes me 90-120 minutes.  On subsequent nights no changes are made to any of the ME ’s physical positioning mechanisms, and  I can then do the following procedures:

 

What did not work very well for me?

 

Comment:  Positioning the equipment while sounding simple can be a bit esoteric.  There are two major alternatives:  First, permanently fix the heights of all 3 wheely-bar height adjusters and then lift the mount each night onto supports (ie. Something like vibration dampeners). Or secondly, use 1 or more fix positions on the driveway and adjust the wheely-bar’s height adjusters into the fixed driveway positions each night.  Option 1 may not result in the exact same position each night (since you have lifted the tripod off the ground it may not rest precisely over each mark on the driveway); Option 2 may not be at the same level position on the driveway each night (since you must adjust one or more of the wheely-bars height adjusters). 

  1. Driveway Markings:  This was my first approach, and it is essentially what I had been using with the Takahashi NJP platform.  I had made black magic-marker marks on the surface of the driveway.  Each night I would position over these marks as precisely as I could and I would re-level the mount.  After I “homed” the ME however, the first slewing star would not be visible on the imager chip.  So I would either re-sync and begin a short model run or start all over with new ME alignment.  Over time, I became less and less satisfied with short runs, as the pointing accuracy was not as good as I wanted it to be. This option was not resulting in either the same physical position or the same level position each night.
  2. Driveway Shallow Hole:  To position the tripod in exactly in the same physical position as the prior night, I drilled a shallow hole in the driveway-pavers where one of the Wheely-bar height adjusters was placed.  To accomplish a precise position, the other two legs are positioned over driveway markings.  I would re-level each night using bubble levels.  This option was not resulting in the exact same physical position or the same level position each night, and the results were equally unsatisfactory for me.
  3. Adding two Lifting Blocks:  To reduce the need for as much re-leveling I fix just one wheel position into the driveway shallow hole and positioned vibration dampeners over driveway marks for the other two wheels.  This meant that each night I only need to make leveling adjustments on one of the three wheels, and I was anchored into the exact spot at one point.  I also marked the exact screw position on the wheely-bar’s height adjuster and I used 7 bubble levels.  While things began to improve, the procedure was still far inferior to what I could achieve with the polar alignment telescope of the NJP in 10-15 minutes.  There was often the need to re-sync and often a need to do a short model run.

A Fast Procedure that works great:

While moving equipment each night, I am now able to position the equipment so precisely that its performance characteristics seem to be on a fixed pier. This means I only need to move the equipment into position, and there is no need for any leveling, polar alignments, position adjusting, or T-Point short runs; I can just begin imaging. I have invented and produced a proto-type, home-made product “Pier-Paws” for making this work. Click on this link and you can see the design specifications for my Pier-Paws.

After many nights of testing and now use: It works.  No leveling, no syncing, no polar aligning, no adjusting, no T-Point short runs, just a home and go. [All targets are not always perfectly dead center, but nor was my original polar alignment perfect from the first night. All targets are, however, well on the FLI Proline09000’s imaging chip even with a focal length of 2348mm... Wow!!!]

  1. Use two Driveway Shallow Holes:  This fixes the position precisely, with no possible deviation.
  2. Use three Lifting Blocks (Pier Paws): which eliminates any need to re-level.  (Perform Step-0 using Pier Paws. Then firmly fix the position of all Wheely-Bar height adjusters, as they will no longer need to be moved.)  The height-adjusters are fixed high enough to be very solid and high enough to be out of the way and thereby allow for easy movement of the platform every night.  The lifting bocks are placed into the same position and orientation each night.
  3. Fit two pegged Pier-Paws into the driveway holes at two wheel points (thus fixing the position), while using a non-pegged Pier-Paw for the 3rd wheel.  This simplifies the driveway hole making (as a 3rd and final hole does not have to be precisely drilled) and still eliminates the need for re-leveling and position adjustments.
  4. Fit all Wheely Bar height adjusters into the tops of the 3 Pier-Paws.  Since my platform exceeds 300lbs, I use a car jack to lift the mount each night on and off the Pier-Paws.

The end result is very fast movement and setup.  Each night I am able to simple roll out from the garage and position the wheely-bar on top of the 3 Pier Paws, connect my cables and I can begin imaging.  For me this is a vast improvement over my earlier setup times, and it is even faster than what I can do with my TAK NJP which still requires nightly re-polar alignments.

See my full astronomy website at: http://SchickWorld.com/Astronomy/Index/AstroIndex-Main3.shtm

Mel Schick, June 2007