Old scopes and new scopes at HJRO photo from 2010

Here's a picture from the summer of 2010.

This shows the old telescope, which is a white 10 inch Schmidt Newtonian, built in 1963 by Nelson Lewis of the Detroit Astronomical society.

In the back by the wall is the old tube, which was disposed of (more on that later). You can see that old tube was 9 feet long. That telescope was also completed around 1962, before the observatory was built. That large tube held a 12 inch Newtonian that our middle school/ junior high astronomy club used to operate.

So there is two telescopes that are old, but one is disassembled with the mirror coating damaged and the mirror removed. The white tube ten inch telescope was used by many years from 1984 until 2003 or so by "the telescope man" a FAAC member named Harold Thomason. Harold had thousands of people look though the white tube telescope many in Dearborn Michigan in front of the library and police station. This telescope has a nice history,

When I saw the Newtonian telescope listed and overheard Harold talk about it, I wanted to see it. I checked out the white Newtonian and when I first saw it I was reminded of all the old telescope ads in the old days when large white tube Newtonians were in an making the person in the foreground look small. This Newtonian reminded me of those old Newtonians on their monster mounts and it was a little intimidating, to think about setting it up and using it. When I looked through it I was blown away by the optical quality. We looked at Jupiter and there were some clouds and dew the night I bought it, I could tell this was a great optical telescope and also it had a really nice wide field of view being an f5.35.

The Schmidt corrector was custom built back in 1962 by the same company that was building Celestron corrector plates.

In 1984 when Harold bought the telescope he called the company that built the corrector and asked what a replacement would run. When he mentioned the focal length, the guy on the other line said, oh that's a custom size. We can build one for you but you won't want to hear the price.

The price for a replacement corrector $1800.

Harold wanted to know in case it was broke. Of course at that price, if the corrector broke it would be cheaper to purchase a new telescope.

For the next several years Harold used the telescope and finally he had other smaller telescopes and a C14 of his own, so it was time to get rid of the big Newtonian. That's how I ended up with it.

Harold made a few different modifications with the telescope. I haven't really made any and probably could do a few things with the scope.

The telescope has a very small secondary mirror and is setup for visual viewing, not astrophotography. The mount is a mount Harold bought in 1984 for the telescope. The mount doesn't have a DEC motor just right ascension. The motor pulls 1 watt of power. It's an AC motor.

The mount is on wheels. I can wheel it out of the observatory, but I have to be careful because we raised the floor when the club and volunteers rebuilt and refurbished the observatory and the floor being raised, makes the door much shorter, so care has to be taken when wheeling it out as the scope has to be tilted and aimed out the low doorway before being wheeled out. Also the size of the base makes this a very careful and difficult process as the base has to be fitted through carefully.

Sometimes the telescope is stored in the observatory, other times I remove it for observing or storage elsewhere.

That's a little bit of history on the old telescopes.

The old large tube telescope was on a mount that was a manual mount that had been constructed with coffee cans and cement as counterweights. The old mount and scope were replaced with a new mount and telescope thanks to a grant from Toshiba Inc that the school system won. This allowed the school system to get a renovated observatory for basically no cost. There were many donors, and there is a plaque with some of the donors from the restoration in 2009.

We have a c14 and Losmandy Titan mount with a Meade 80mm f6 APO refractor and a Lunt 35mm HA solar scope in the observatory. We also have a couple of basic cameras for the observatory and I bring a t mount for anyone who happens to visit who wants to mount a canon Eos camera on the telescopes.





Things look a little different today. The tall dark Newtonian tube is gone, it's actually in Dearborn now.

There is a large shelving unit inside the observatory today which is not shown in the photo.

Greg

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The sun today as seen by many 8th grade students at HJRO.

Below is a photo I took today of the sun through our solar scope in the observatory.

The sun today through the hydrogen alpha Lunt solar scope.

This is a 35mm dual etalon filter solar scope.

Photo taken at 1/60th of a second handheld with canon t1i Eos camera.

Altered slightly with curve filter bringing up RGB mid tones a bit and sharpened slightly. (program app is called Filterstorm for iPad.)

The faint curved pattern that looks like a wave shadow on the left side is artifacts from the RGB color sensor in the camera. A monochrome image sensor would not show those false patterns.

The rest is pretty close to what was visible, but detail in the scope was better for those who saw it in person.

We had six classes of thirty students visit today during the day.

The first two classes were not able to see the sun because of clouds however.




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Economics of restoration

It's difficult to justify the cost of restoring old telescopes. Especially when they are old homebuilt telescopes. If they are large and have an old mirror in them they might require recoating or in the case of the telescopes from HJRO that were disposed of, re-polishing or re-figuring.

In the case of the f5 8 inch it could take a lot of work to republish the mirror, this would involve building a tool and setting up a pitch lap to match the telescope. Removing the old coating and then setting up a stand and test equipment to do measurements. Polishing a mirror is the most difficult and precise step in making a mirror. The pitch lap is sitting on the mirror with a type of polish that is almost like maple syrup in consistency. It's a fine polishing compound that is more like syrup than fine grit that is in a water when you are grinding the mirror. The mirror moves stiffly on the polishing tool which sits below the mirror. The fine grain or more like lack of grain in the polishing compound makes it difficult to push and pull the mirror in strokes as it's moved and sits on the mirror tool or pitch lap on the mirror tool.


A mirror tool normally is created when the mirror is build, a matching piece of glass that is the opposite shape of the mirror and has a convex curve that matches the concave shape of the mirrors surface.

The pushing and pulling of the mirror over e tool takes it's toll on the backs of those working to finish the mirror. Many mirror builders when they get older and have more money have said to me, "mirror building doesn't require much brains, but you need a strong back.". I can testify to this when we build mirrors back on the 1970s.

So what does it cost if you get a professional to fix the mirror. I got a quote from a premium mirror builder to get an idea what it would cost to restore the mirrors that were in the two telescopes in HJRO.

The old 12 inch would cost about $1000. The old 8 inch mirror $600. This does not include aluminizing the mirror, which is an additional expense.

Now let's consider the other expenses to fix the 12 inch and get it up and running. The tube was pretty heavy, it's large and rathr long at 9th in length. It would require a mount that was heavy and well build a permanent pier, a large cover over it, likely another observatory dome. And it would be a narrow field of view instrument. It's f7.17 in focal length. It was close to perfect and would likely cost close to $1500 to restore the mirror.

The mount would have to hold a huge telescope and you'd need a big ladder.

The mount would run $5000 or more. The ladder might cost $600. So we are in the $7000 range to restore the telescope without building an observatory.

I have found memories of the telescope, but I don't have an extra $7,000 laying around to restore this old telescope.

Now consider that a member of the club has a 12 inch f5 reflector, a MEADE light bridge Newtonian truss telescope for $600. This is a used telescope and has an f5 focal length. That's a lot wider field of view and it's a Dobsonian telescope. I have no doubt the mirror on the old telescope is better for viewing planets than the light bridge, but the light bridge is portable and it's less than the cost of starting to fix the mirror in the smaller 8 inch Newtonian.

There are a lot of good telescopes out there already build and also in the usd market. This is why many won't build telescopes today or fix old telescopes.

It's a lot easier to buy a new one.

Sometimes old telescopes end up in a museum or showcase in a large observatory display. We don't have room in the Lincoln Park museum for that huge 12 inch tube. It's old and looks beat up. It's large and to stand it up on end means it can be tipped over. It's rather large to hang from a ceiling. This is why old tubes often end up in the trash.

I squirreled away the old tube at a friends garage. But he's run out of room. The telescope has no practical value, so today it's going to finally be disposed of.


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The observatory should be open tonight

We plan on observing tonight at HJRO. Visitors are welcome but children should be accompanied by a parent.

DETAILS and more ramblings of a tired astronomer.

It's clear out today and many Faac astronomers are wisely sleeping and catching up on some missed sleep from last nights viewing.

We were open last night but I only announced it on the FAAC yahoo group last night and not my blog. If you drive by and see the dome and shutter open please feel free to stop by and visit. I don't always announce openings here, especially if we have group visiting or many people asking me if we will be open.

We will be open tonight and basically anyone is welcome. There are some little technical problems we've been having with the mount, which we will work around and have been working around.

We looked through the C14, Big Bertha a ten inch Schmidt Newtonian, a small Bushnell telescope and my vixen binoculars. We didn't look through the small Meade refractor at all last night.

We had about a dozen people attend viewing last night. They were able to look at Jupiter, the moon and other objects as well. We looked at the ring nebula and the dumbbell nebula. There were other objects they looked at, but part of the time as others were operating the telescope I was outside setting up other telescopes with and viewing M45 and Jupiter outside.

Early in the evening we had three visitors, the family of school worker last night and we had one of our members brought another youngster for observing. We also had a Faac member bring two college age guests. And then there was Tim, Art, Rick, and last but not least Brian all FAAC members there to observe, chat and generally have a good time. For most of the night Tim, Art and others ran the telescope and I was able to wander around and hopefully not distract others to much. Jennifer our FAAC newsletter editor (and president of the HFCC club) was there as well. She stopped by for a short visit and probably stayed for about an hour.

Seeing was at first was a little marginal, with some thin clouds early on. Visibility improved to "very good" as most of the clouds were gone by about 9:45pm. Seeing and transparency were very good and we could see a lot of detail when looking at Jupiter. We were able to get some pretty high powered pictures when Brian was there later in the evening.

Brian met some of us during a break at White Castle on Fort Street, and we returned to view with Brian from about 12:30am to 2am. After Brian left, Art and I looked briefly at M42 and then we closed up at 2:30am.

We expect to be open tonight. Parents can bring kids out or kids can bring their parents. This is a nice way of saying it's not a night where we have teachers out so children should be accompanied by parents.

-- To fix and adjust my big ten inch telescope, that "fell"
We will be doing some work, likely in the early evening perhaps with the mount and also perhaps optical aligning Big Bertha, my ten inch newtonian that is currently setup at the observatory.

I had a slight accident last night and that large telescope actually fell over with it's mount while I was moving it back into the observatory. The tube weighs 50 pounds and the entire rig weighs 200 lbs, so you can imagine my surprise as I tried to slow down the fall of this telescope as it started to tumble toward the ground. This happened while I was moving the telescope and happened because I was rushing a bit and in a hurry. One cardinal rule of astronomy should be take your time and be patient. That's a rule I broke, and I almost broke my telescope because of it.

This happened because I was rushing and didn't slowly keep and eye on the telescope and mount. I had a temporary mount adjustment I did. Believe it or not I had a towel that was locked into the mounting bracket and it was a large towel that can drag and hang down. This was a dumb adjustment fix, and it should have been removed.

This was temporarily fix using the towel as a bracket spacer to have the tube locked in more tightly in the mount. The mounting brackets foam is old and I was using the towel to act as a shim to allow the tube to be in the bracket more securely, but that towel was to large.

When I was pulling the telescope and mount (on wheels) into the observatory, one of the wheels of the mount caught the towel that had fallen down and was dragging on the ground. I didn't notice this. When the wheel caught on the towel the entire telescope and mount tipped and started falling.

Fortunately I was in front if it and basically partially slowed the fall as it fell partially down on my leg and ankle. This slowed its fall enough to prevent the telescope from a major break. Had the front corrector plate broke, it would have been a total loss of that telescope which was built in 1962 and has had thousands of people look through it.

Fortunately it didn't break, but a scrape of blue paint is on the tube from it sliding partially against the door of the observatory on it's way down. That paint can likely be removed and buffed off, or remain as a battle scar.

So we may spend a bit of time adjusting the optics on that ten inch Schmidt newtonian telescope and I need to rework that mounting bracket removing that towel.

Tonight we will be observing Jupiter, the moon and other objects.

Last night near the end of the night we observed Jupiter through the C14 and saw a lot of detail, but we could not see additional detail with a 13mm eyepiece or most high powered eyepieces at the end of the night. This could have been due to sky conditions deteriorating as far as viewing. It could also have been due to heat thermals inside the observatory as we had a heater on for a short break between observing sessions and that added heat is something that can cause hot air to rise and ruin viewing. We typically turn on a heater at the end of a cold night to warm up but not during viewing.

It's very cold out so dress warm and in layers if you decide to come out, because it's easy to get chilled and cold. Remember clear skies allow the heat to radiate back into space quicker, so when its clear out the nights will often get cold quickly. So dress warm if you decide to go out and observe tonight or stop by to join us.

Some visitors stay for ten or fifteen minutes, look at a couple of items and then move on. Others stay for hours, but on cold nights they should be prepared and dress warm. One rule for astronomy is You cannot be dressed to warmly. Dress in layers, if your dressed to warmly you can always take off some extra item.

We have one coat we can loan people, but little else to help someone warm up if they are cold. Sometimes we take a break and send someone out for hot chocolate. Last night Tim brought a heating pad to sit on. The theory we are testing is we might be able to have a heating pad or two to sit on in chairs and warm the astronomer without effecting visual viewing much. But in reality any heat, even the heat from one human body standing in front of the telescope can cause thermals to rise up and disrupt imaging. Some die hard imagers who take astrophotographs, report that they can see thermals from deer who walk near their observatory and they will never even walk in front of the side of the telescope when they are imaging. They keep thermal heat currents down.

During late night imaging last night Brian noticed some images going out of focus. I opened and closed the door to change air currents as there was a slight temperature difference and it was colder outside with a slight breeze outside. My thought was different cold air rising through the shutter might cause the image to improve. The air likely rushed through the dome more as it was cold air and a slight breeze was felt in the open doorway. That didn't improve the image, but actually degraded it. So we shut the door.

We experiment a bit and learn each night. Probably for most visitors looking out they will not notice the difference in the view with their eyes on the eyepiece if we have some heat or even the IR heater on facing someone behind the telescope. We test this sometimes, especially when some visitors are feeling the cold.

It's a bit of a challenge sometimes. Some FAAC astronomer visitors dream about the day we might have a warming shack or building nearby, perhaps next to the observatory that can be heated for astronomers and guests. We might use that as a control room, to store extra chairs and perhaps as a presentation Av room. It would be nice to have a warming shack of course next to the observatory for guests and astronomers. We are of course dreaming and haven't made any serious proposal or decision to try to lobby for that yet. We might even bring a trailer and park it nearby to use as a control room near the observatory. Control rooms are more useful to astronomers who are doing more imaging. For an observatory where the public is visiting, it would likely be better to use some additional small building or trailer as a warm up shack most of the time, just a place to warm up, perhaps look at computer software and charts. It's difficult to say all the advantages we'd have from a second structure.

I can write more about this in another blog entry later.

As you can see I'm writing a long post this morning and probably need more sleep.






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Jupiter near opposition looks good when the sky is favorable

In the last week Jupiter was at opposition, closest to the earth and opposite the sun. During on clear night a couple of other members of the Faac club and I looked at Jupiter. The view was one of the nicest I've seen all year.

I could see 8 or 9 bands and fine gradients in color in the planet.

The attached photo was taken with my Canon t1i. A single exposure through a 25mm eyepiece. The detail looked better to our eyes than this photo shows.

I was actually out late at night a few nights last week. Unannounced as I got out there late. There was a lot of humidity and the air was cold and dqmot a couple of the nights, but the views were worth it.

I felt a bit of cold in my old bones, and that chill drove me out of a couple of the observing sessions with temperatures in the high 30s. That cold damp weather requires serious warm clothing and I found a good winter coat, layers and long underwear helped a lot.

We turned on the IR heater during part of our last observing session, and that helped take some of the chill off. Wooden floors help some.

It was cloudy and hazy out tonight. I have not looked at the sky as I type this very late at night tonight. I really don't want to go out tonight or be tempted with a great view. I'm resting up a bit. I kind of tweaked my neck looming up to high through an eyepiece and have been resting a bit hoping the pain will decrease.





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