Lockwood Custom Optics at Hidden Hollow 2012

The new 36" f/6.3 mirror makes its public debut at the Warren Rupp Observatory, and I am there

All images and text Copyright Mike Lockwood, 2012.  May not be used without permission.


Being an amateur astronomer and living in a particular part of the country, there are certain telescopes that you hear about.  Stories about them are told by fellow club members who heard them from their friends.  Observing stories are overheard at star parties and other events.  Over the years they develop a reputation in your mind even though you have never seen them in person, or used them for a night of observing.

For me, the 31" f/7 telescope, nicknamed "Big Blue" at the Warren Rupp Observatory was one of those telescopes, along with instruments like Tom Clark's 42".  (To my surprise, by the end of the year I will have worked on the optics for both.)

I lived in Cincinnati for a few years, and heard quite a bit about the 31" f/7.  I always hoped to visit it some day.  Its history can be read here and in another version here, and construction photos can be seen here.

An email one September evening dashed that hope, but at the same time started a new chapter in its history.

It was the evening of September 13th (no, not a Friday, a Tuesday!), and I was in my shop getting some work done.  An email came in from Mark Vanderaar, the president of the Richland Astronomical Society at the time, bringing the news that the 31" primary had been broken when the secondary mirror assembly fell and hit it, splitting the mirror literally in half.  I was on the phone with him within an hour, and we talked about options over many phone calls in the coming day.  Fortunately there was insurance that could cover the damage.

Eventually, a plan was hatched to improve the telescope, by adding a new mirror cell to handle a larger, but thinner 36" f/6.3 mirror.  Obviously improvments to the secondary mirror holder and a new secondary mirror were needed, too.

My "In the Shop" installment about making the primary mirror can be found here, and soon it was time to head for Ohio to go visit what I began calling "Bigger Blue".

A trip to Ohio

It was a beautiful day for a drive as I made my way from Illinois to Ohio.  A blue sky and comfortable temperatures hinted at a good night's observing ahead, and I arrived at Hidden Hollow about 3:30pm, in advance of my 5pm talk.

In the back of my Outback was the crate holding the two pieces of the 31" mirror.  We had hoped to have some other blanks machined from it, but after the coating was removed it showed a lot of bubbles and some interesting internal strain.  So, this was a first - I pointed out that I "had never delivered a broken mirror before" as we solemnly unloaded the crate.

The terrible event still weighed on the minds of some that I was almost afraid to make any kind of a joke about it, but sometimes you just have to find a way to laugh.  However, with the new mirror and other improvements, we all knew that the telescope had been born again and improved, and that this was an incredibly happy occasion, not one for mourning.

I took a short tour of the area, and took some photos before giving my talk and having dinner.


Welcome to the Warren Rupp Observatory, and thank you Warren.

The observatory as darkness nears

Let's have a walk through the doors......

A look through the doors

Oh my, that's one BIG telescope (though the perspective and lens distortion makes it look smaller from this viewpoint).

OK, I need some people to get into the shot for scale, any volunteers?

It's a big telescope.

That's better.  Pictured from left to right are John Neumann, Mark Vanderaar, and Bruce Scodova.  The hydraulic lift used for observing frames the photo on the right side, with the polar axis of the telescope at upper left.  A massive counterweight (outside the photo at left) balances the massive instrument.  The walls are painted black, the inside of the dome is its natural aluminum color, and the telescope is a very pretty shade of blue.

New mirror cell and cooling fans

Here's a look at the brand new mirror cell/tube extension that holds the new 36" mirror, complete with back and side cooling fans.  The three hand-wheels are the collimation adjustments.  Some experimentation regarding directions, speeds, etc., was done with the fans, but this was one of the first nights of the scope's operation, and there was not much time for it because there was a line of people waiting to use the telescope!

Note the small white rollers on the left and right sides of the mirror - they are part of the mirror's edge support, which is formed by whiffletrees that go all the way around the mirror.  This is an equatorial telescope, so edge support is not as simple as with an alt-azimuth telescope like a Dobsonian-Newtonian.

I gave my talk in the lower floor of the Sky High Lodge, and then some of us went out for dinner.  We returned and waited to darkness to fall as more people arrived.

WRO in darkness

As darkness fell, people began observing inside and outside the dome.  With a line forming, I was able to do some quick star testing to see that the correction of the mirror was quite good, and after the mirror cooled off a bit and was given a little nudge away from the edge supports (which need a little adjustment), stars were as round as could be expected at 500x while looking through the slit of a cooling dome.

The cell and cooling fans are working quite well, though the edge supports will need a little more adjustment to perform at their best, as expected.  Large telescopes always require some tuning to work at their best.  Another possibility is some fans in the dome itself to help draw outside air through and reduce "dome seeing".

Overall I was pleased with the images, though I did not get to see M27, which seemed to be the favorite object of most, through the 36" until some high clouds had come in and obscured it somewhat.

Later on Friday night, the scope was turned to Stephen's Quintet which showed more detail than I could recall, with the possible exception of a 32" telescope at a darker site.  M57 showed its central star quite obviously at times, going in and out with the seeing conditions.

Gradually clouds increased, so I turned my attention towards taking some nighttime shots of the telescope and the dome.

Using the dome shutter as a shutter

Rotating the dome acts as a shutter, so with the camera's shutter open, the entire inside can be seen.  The light to the right of the dome is the path of someone's red flashlight during the exposure.  Light pollution from Mansfield, OH, is seen above the dome, to the northwest of the observatory site.

Another shutter view

This version shows the telescope in more detail, and aimed a bit differently.

The dome by red light

With a small tripod in hand, I took the camera into the dome, set it up near floor-level, and did some exposures with a wide-angle lens.  I even managed to capture M31, the Andromeda galaxy, just peeking over the top end of the telescope tube, just above the finderscope that is on the bottom/right of the tube.

The scale of the telescope can truly be appreciated when notes how high up the lift is positioned, and the relative size of the person standing on its platform.  A computer and monitor are secured to the lift, and the computer interfaces with encoders on the telescope to show where it is pointed.  It's a very nice system.... so long as one of the hand controller buttons doesn't stick when it is handed to yours truly to help center up a star, who then panics when the telescope won't stop slewing toward the lift!  (Luckily the scope has a clutch drive, and there was a spare hand controller.)

After observing a bit more and continuing to shoot photos, at about 3:30am I had to turn in due to fatigue.  I had gotten up fairly early to get a good start on the 6+ hour drive, and it was time to sleep.  I did so for quite a while.

The WRO site

Saturday morning was beautiful, and after sleeping very late, a small, late breakfast was rapidly followed by my lunch of leftovers from the previous night's dinner.  After some more caffeine, I was ready to walk around and get some daytime photos.  The shot above shows the hill that the observatory is situated on, with a club building built into the hill (to the left in the photo) to warm up in.  It also has a nice restroom.

If you ever observe there, be aware that after coming down from the tall lift that gets you to the eyepiece, and after exiting the observatory, there is a rather steep hill that can be fun to negotiate in the dark!  There are stairs on the right side of the club room, behind the hedge.  The hedges to the right up on the hill surround a fire pit area that has to be really nice on a cool, cloudy October night.

But what's that in the extreme right of the photo, amongst the hedges?  Get to that in a minute.

Just in case you aren't sure where you are\

Up on the hill lies a sign that makes one's location obvious.  I am standing on the side of the hill to take this photo.  Now let's go over to the right a bit and see what that mysterious object was.....

Wait a minute, it's a 20" Super FX-Q!

Hey, it's a 20" f/3.3 Starmaster telescope, known as a 20" Super FX-Q!  I make the all-quartz optics for these no-ladder-required telescopes.  When the line is long at the 36" scope, I know where I'll be headed.

Observatory and club room

Walking past the dome, a view from the other side of the club building shows the hill.  The restroom is on the near side of the club room.

Seriously, though, can we get some photos from a different perspective, I wonder?  Turns out, that is not a problem.

View from above, observatory and club building

One of the club members drove the lift carefully through the exit to the observatory, and up we went just outside the dome on the sidewalk.  Oh, and I decided to put a fisheye lens on my camera, and shoot multiple exposures of various exposures.  These were combined with software to form HDR (high dynamic range) images that show the dark inside of the dome, as well as the very bright outside environment around the dome.

These shots also capture a full 180-degree view from the camera's perspective, including part of the lift, a lens and lens cap, some tools, and my feet at the bottom of the image!  The building at left is a club building for telescope outreach, various meetings, educational outreach/classes, and telescope storage.

Observatory and observing pad

Looking the other way, we see Bruce standing in the dome to show the scale of the 31", as well as the large concrete observing pad where members can set up telescopes.  There is also an observing table, picnic table, and a storage room above the club room in the "attic" of that building built into the side of the hill.

Alternate view of the telescope

Another view of the telescope with the lift, with the very patient Bruce standing by its base for scale.

Another scope view

Here's the telescope pointed nearly vertical for a slightly different shot.

Charlie Warren shares the lift

Charlie Warren, the publisher/editor of Amateur Astronomy Magazine, also shared the lift with me, so no doubt you'll see some of his shots and possibly mine in a future issue of that magazine.  Charlie's astronomy home on wheels is just to the left of his head.

My reflection in my product

Finally, I couldn't resist the shot with my reflection in the primary mirror.  (No, the mirror did not break.)

Special paint

How did the new mirror cell get to be that beautiful blue color?  John Pratte of JPAstrocraft.com, who built the cell, mixed up a bottle to match the original color.  I'm guessing there are not too many bottles of "Big Blue Blue" sitting on the shelves of your local hardware store......

Now we move on down the road a bit from the observatory to the Sky High Lodge, where vendors were located and my talks were given.

Through the woods to the Sky High Lodge

On the way you will see plenty of cabins for the campers that occupy this part of the property for most of the summer.  The camp is operated by Friendly House, and is quite popular in the summer months.

Accommodations for campers

This cabin gave me a sugar craving.

The Sky High Lodge

Here we are at last, the Sky High Lodge, situated on the top of a hill overlooking a valley.  This is a large building with plenty of space for vendors, presentations, and other things.  Turning around, we see the view below.

View from the front of the lodge

This is the view from the side of the lodge shown above.  We saw a number of deer at the bottom of the hill near the woods.

Inside the lodge

The inside of the lodge had plenty of space for lots of activities, and a darker room on the floor below was set up for talks using a projector.  I gave another talk on Saturday afternoon.

After dinner on Saturday, clouds began to increase.  The public enjoyed the views through the 36", but the sky got worse by the hour.  By midnight, the summer triangle stars were just about all that could be seen.  So, of course at that point people sit around talking, and this can turn out to be one of the most enjoyable times at a star party.  We spent some time playing around with an image intensifier, looking around to see what was going on around us as some off in the shadows enjoyed a tasty beverage, or perhaps several.  People were gradually turning in, and with a long drive on the following day, I did too.

I packed up on Sunday, pleased with how the telescope was performing, but hoping to get back for some more observing under clearer skies.

Donations are appreciated

So, if you can make it over to north central Ohio, stop by and enjoy the views, and if you can, leave a donation to help Bigger Blue operate and be improved in the future.

Here are some relevant links again:  
Warren Rupp Observatory, and Richland Astronomical Society.

Clear, dark skies, warm weather, good friends, and good seeing.

  -Mike Lockwood, Lockwood Custom Optics

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