FoucaultFringes

October 16, 2014:  50" telescope dedication

       All text and images Copyright Michael E. Lockwood, all rights reserved.


I completed the optical work on Bob Holmes' 50" mirror for the second time earlier this year.

The first time the mirror was damaged during the coating process by strong chemicals that were used to "clean" it prior to coating.  This destroyed the figure over much of the area of the mirror.   Additionally, there was a malfunction and molten aluminum was splattered all over the mirror, causing small fractures where it hit the cold glass.

For more information on the potential damage that can be done in the coating process, see my short article here.

Luckily there was insurance to cover the cost of reworking it.  I ground through much of the damage and many of the bubbles that had intersected the old optical surface, resulting in an optical surface that was more free of bubbles and small defects than before.  (This was the one positive about re-grinding the mirror.)  I then polished and figured it for a second time.  It turned out very nicely this time, too, and I was pleased with the figure.

A different coater was chosen, and they followed our cleaning procedures and did an excellent job coating it.

The main problem with the re-work was the time that it required, which set back my schedule quite a bit on many other projects (my apologies to those clients whose mirrors have been delayed by this), but it had to be done.

So, it was a very good day when the following card/invitation appeared in my mailbox.

InvitationInvitation inside

Bob's observatories are located a short drive from Eastern Illinois University, which is in Charleston, Illinois.  Bob is about an hour's drive from my shop, and John Pratte lives in Charleston.  So, all of the skills needed to bring this telescope to life were located within an hour of Bob.  What are the odds of that?!?

Bob has worked with EIU for a number of years, and became an adjunct professor.  He works with students and faculty who also use his instruments, in particular the 30" f/3.  So, there is a good working relationship between Bob and EIU.

Finally the night arrived, with a forecast for clearing skies, and cool, but not cold, temperatures.  I arrived a bit early to shoot some photos before the sun went down.

Sunset at the dedication

Bob had the roofs of all the observatories open except for the 50", since it was to be revealed during the ceremony.  This way the telescopes would also be cooled off so Bob could use them later that night after the event was over.  There was a nice buffet brought in by the caterers.

EIU President speaks

After an introduction by the head of the Physics department at EIU, university president Bill Perry gave a nice speech just before the roof was rolled back on the 50" building.  Bob also said a few words, and thanked all those who contributed, including myself and John Pratte.

Then, with the roof open, the telescope slowly emerged as it was pointed upward.  More than one of us was tempted to play "Also sprach Zarathustra" (better known as the music that plays during the opening of 2001 - A Space Odyssey) as the telescope appeared over the walls of the observatory.  I could have done that - I had it on my iPod which was in my car!

Bob points out features of the 50" to EIU president Bill PerryBob and I in front of the 50"

Everyone ventured into the observatory to get up close and personal with the giant instrument.  Above left we see Bob Holmes pointing out features of the telescope to Bill Perry, EIU president.  The photo above right shows me, wearing my ARI pullover, with Bob and the 50" f/4.

The evening winds down

As the party wound down, I managed to hand-hold a nice shot showing the 30" (front) and 50" (rear, with red upper ring) telescopes pointing skyward.  Lights in the 30" observatory illuminate the scene.  The other two illuminated doors at right are the entries to the 32" and 24" telescope buildings.  At left, Bob Holmes talks to a few remaining guests.

Eastern Illinois University also posted a nice article/press release about the telescope.

Here is a link to Bob Holmes' web site.

Even though the scope became operational a year later than it should have been, it was very rewarding to see some recognition for everyone who helped bring this instrument to life.  The telescope has already hit 24th magnitude with ease on an NEO, and it is just getting started.

Please check back for future installments of "In the Shop".

Mike Lockwood
Lockwood Custom Optics

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