A story about a Starmaster EL 11" f/ 5.4 with Zambuto Optics

Posted by Tom Hole   11/08/2004 08:00AM

A story about a Starmaster EL 11" f/ 5.4 with Zambuto Optics
[ARTICLEIMGR="1"]A Diary

Went nuts and bought this on 24 Nov. I'll be picking it up early Dec. Holy cow, is that a Zambuto in there?

14 Dec 2003 - It's here. I picked it up last Wed and it's been raining and snowing ever since. I was able to use the eq platform and accessory tray that I had made for my XT10. You can also see the 3 magnets laying on the back of the mirror box for balancing the binoviewers.

A frosty morning

It was the best of times, it was the worst of times, it was the best of times

I knew I wanted premium optics and I sold every telescope and a very nice custom GEM that I owned at the time (ST80, XT10, Burgess 127/8, Gemini GI-1 GOTO GEM) so I could pay for a new Starmaster 11 EL. The last year has convinced me that I made a very good decision. This might not be the right choice for everyone, but for me, it was a perfect fit.

I only got started in this hobby in Dec 2002 with an Orion XT4.5 that was purchased for my kids. They have not shown an independent interest in astronomy, but they do enjoy the occasional wow when Daddy finds something cool. I, on the other hand, was hooked. I started with the Orion XT line and fell in love. I tinkered and modified my poor XT10 until it was almost a cyborg. I dabbled in GEMs and achromatic refractors. I really enjoyed myself a lot playing with all manner of telescopes and accessories. I built an observing chair (actually, 2 of them) and an equatorial platform. I discovered binoviewers and binoculars. I went from Sirius plossls to Naglers. Astromart was my playground. I never had a large investment wrapped up in any one thing, and even the total was quite reasonable when compared to my model airplane or band hobbies.

But I was always curious about the premium kit. The AP refractor or the Zambuto dob. So, it does not surprise me at all that I ended up with a Starmaster. Over the past year, it has given me immeasurable pleasure knowing that I have the best 11" telescope that could possibly be made. At least for me wink

Alas, my world was not perfect, though. I enjoy tinkering with my stuff almost as much as I enjoy using it. After spending several months with the Starmaster, I found the only modification I could think to make was adding some cooling fans to it. It probably didn't need that, but it made me feel like this Starmaster was now Tom's Starmaster. I've thought about other mods, but those thoughts have passed. So, I have gone back to executing the honeydo list, much to the pleasure of my wife.

Well, one day I was out checking something or the other on the scope. I use these large magnets wrapped in duct tape as counterweights to balance my binoviewers. I keep two of them velcroed to the back of the mirror box and three of them perched on top of the back of the mirror box resting against one of the transport handles. Well, I was doing something that required me to put one of these magnets on the UTA to keep the nose down. Maybe I was working on the bottom of the mirror box, I really don't recall exactly. So, I finish up with whatever task I was doing and decided to lift the nose of the Starmaster up.

Well, doesn't take a super genius to guess what happened next. The first indication I had that something was terribly wrong was the sound of the magnet hitting the mirror. At first, I had no idea what the sound was. I looked in the mirror box and initially did not see anything. Then I saw the chip in the mirror and the magnet lying innocently against the side of the mirror box. There are worse things that can and do happen and certainly chipping my beloved ZOC mirror was not as bad as those. But it was a terrible, sinking feeling, nonetheless.

DRAT!

I looked at the mirror for what must have been several minutes, trying to determine what to do next. Is the chip behind the secondary? Nope. Is it actually chipped? Yup. Will it affect the view? Well, I checked it over several evenings and the images and star tests were both as good as they were before. What should I do? Every time I collimated the scope, a little of that sinking feeling came back. It gave me the heebie jeebies every time I looked at what I had done.

Now, if you think I was making too big of a deal out of this, you are absolutely right. But for the same reasons I had to own a Starmaster, I also had to own a perfect Starmaster. So, I wrote an email to the one person that would know best what to do: Carl Zambuto. Here is the email:

Carl,

I am the guy that dropped a magnet on my beloved ZOC mirror in my 11" Starmaster El. After the gas giants depart, I would like to send the mirror to you for fixing. Whatever it takes to return it to perfect CZ condition. Whadya think it might cost? It will definitely need to be re-coated and may need some TLC from you. Just looking for a ballpark (+- 30%).

Thanks,
Tom

Carl told me that it was unlikely that the damage would effect the view, but if I wanted him to evaluate the mirror to send it in. He sent me a shipping box and I wrapped the damaged mirror up and sent it off to Carl. Here was his prognosis:

Tom,

We received the mirror and inspected it. Good news and bad news. First the bad- the glass is fractured down into the substrate about 1/4" deep. It is not fixable by any reasonable means, as it is too far to grind to completely eradicate the fracture. At first glance we knew it was in trouble, as we saw obvious glass missing in the surface, plus, an area where we could see by reflection at an angle that the surface was actually changed in slope. So the damage was immediately obvious.

We did indeed strip the coating for a thorough inspection to see how deep the damage went. Attached find a photo of the glass under strain test. We're running polarized light through the glass, looking through the front at an angle. The large circle is the Spectrum label on the back. You can see changes in color (hue) around the chip, and that the chip is an arc that extends into the glass. My best guess is about 1/4" deep, at minimum. The fracture is producing strain that extends out into the glass a small distance. We would not grind that out, it is simply too much glass to remove by grinding, so by our standards, this mirror is not repairable.

Now the good news, if you can consider it good. The mirror is still usable, as you already know. With a coating in place, you could make a flat black circle over the fracture and use the mirror as it is. We did do an optical test on the mirror, to see the effect the chip makes. It does indeed cause surface changes spreading away, mainly in two directions, but outside of 1" diameter circle the effect will be minimal. So, in short, the mirror could still be used and it will perform well, for what that's worth.

I can offer you one other option in this situation, and that is to fabricate a replacement mirror. We don't do this size and F/ratio as a production item any longer, so it is a one-off. I would charge you a price comparable to what we charge our telescope makers, and ask that in exchange for tooling up to do a one-off (as well as re-grinding an 11" blank to a different curve) we would keep the glass for a mechanical reference for the grind shop. A Pyrex blank this size is worth about $135.00, but this one is useless to us in its condition for making a mirror because of the deep fracture. However we could use it to put a spherometer on, and use as a reference for grinding. It would get scratched up much worse over time, which is what our grinding reference tools do (basically, for our purposes, its a hunk of glass with a curve in it). The price for a replacement mirror for your Starmaster would be $1,100.00 shipped to your door.

So either option is open to you. I can send it to Spectrum to be recoated and shipped to you, or, we can fabricate a replacement. I would estimate we can have the new mirror to you in about 90 days.

I'm sorry the story is not happier than that. The mirror took a hard strike dead-on. We know the look, because it has happened to us as well on several occasions.

Carl

Here is the image Carl referred to:

[[ PICTURE ]]

Not the news I wanted to hear.

I spent the next few days weighing my options and discussing my dilemma online with other astronomers. Everyone universally recommended the same thing: put a black spot over the damaged area and forget about it. So I sent this reply to Carl:

Carl,

Drat! I knew in my heart that would be the prognosis, but until you wrote it, I still had hope.

I made a couple of inquiries online to see what folks thought I should do and the unanimous reply was "just put the black spot on and enjoy the views." So, I think that is what I should do at this time. I cannot afford a replacement right now, but I would like to keep the option available, if possible. Can I call you up in a year and have a replacement made? If not, I understand.

So, how should we proceed? I assume the next stop is Spectrum. Then back to me? I would like your advise on what to use to cover the affected area with. I like to rinse my mirror every 3 months or so (just a distilled water wash down, no scrubbing or chemicals), so something that is not water soluble might be good.

Let me know what I owe ya and I'll send your preferred method of payment straight away.

Again, many thanks for your help with this. Reaffirms why I bought a Starmaster.
Tom

Here was Carl's reply:

I'll send you a statement in the near future, when I can get to it. I'll also include some thoughts on covering the affected area. Meanwhile I'll get the mirror under way.

Tell me, do you have another telescope? Your name sounds familiar when it comes to larger aperture/Starmaster. What I'm also asking is, are you without a telescope while this is taking place?

Carl

And my reply to Carl:

Carl,

Yup, this is my only scope. I sold most every toy I had so I could snag this Starmaster from a local fellow. Previous scopes were China dobs and a Burgess refractor.

I know for sure this will not be the last dob with a ZOC mirror that I own. Just too good.

Tom

And Carl's reply:

Thank you for telling me, Tom. I don't want you to be without a scope for too long, so we'll get you fixed up.

Thanks,

Carl


I was comforted knowing that Carl took such a personal interest in helping with a problem that was clearly my own stupid fault. Made me feel better about being a ZOC customer. I'm sure he treats everyone that way, but I still felt special.

About 2 months later, I was pleased as punch to see my mirror box returned to me on my doorstep. Of course, I'm pleased as punch to see any package on my doorstep. I had mixed feelings as I opened up the package. What would the chip look like? Will it at least look smaller and thus be more palatable? Regardless, it's always fun to open up a new package.

I got the mirror out and uncovered it to reveal a beautiful, shiny ZOC mirror. I looked it over to see how the chip had fared and could not spot it's location. I only gave it a cursory look as I had honeydo's to get to, and never got back to giving it a closer inspection.

Carl sent me an email asking if the mirror had arrived safely (more of that special attention wink, and I sent this reply:

Carl,

First, I must apologize profusely for not sending out payment right away after your last email. I have been on vacation and just got back this weekend. It will go out today. If you accept PayPal, I can send it right now and add 3% for the fee. Otherwise, I will send a check or MO (your choice) straight away.

Second, oh my! Nothing like a freshly coated ZOC mirror to brighten up one's evening. I wanted to ask about the black spot. To be honest, in order to placate my psychosis, I like the mirror just as it is. If you think it won't degrade the view too terribly, I would prefer to just use the mirror as is. Keeps the cringing to a minimum.

I might make a little spot to attach to the secondary and see if I can tell a difference with that. If not, then I won't put one on the primary.

I did want to ask how to find the defective spot. I could not locate it. I only gave it a cursory look, so maybe I just missed it.

Many heartfelt thanks for you help. I can't offer much from the east coast, but if there is anything I can do for you, let me know. I have a collection of pictures of the Super Hornet when we first started flight testing it here at Pax, or if you are ever out near D.C. I can get you or a friend/family member a tour of our flight test facilities (and airplanes) here on base. Anyone you know that's a big Naval Aviation / Test Pilot aficionado?

Anyway, you are a great American.

Tom


Carl sent this reply:

Well, thank you, Tom. My wife says that *you* are the great American.

I'm not in a particular hurry, in that PayPal is not necessary. A check or money order in the mail will do just fine. I think I already sent my mailing address.

Well, since you mention it, I rather like the mirror the way it is, too. You need not look for the defect, it will have no effect on your observing any more. No psychosis or cringing will be required. Put the mirror in the scope and enjoy. "Its on the house".

If we ever get to the east coast I will probably look you up, and take you up on your very kind offer.

My fondest regards, and thank you for being one of our loyal customers.

Carl

(PS check the date for a nice surprise)


I had to read the email a few times as I am kinda thick headed and didn't get it right away.

Once I figured out what Carl was implying, I ran downstairs and quickly (but very carefully wink removed the mirror from the telescope and sure enough, there was a new manufactured date on the back. I was shocked, elated, and to be honest, a little out of sorts. Few things outside my family effect me emotionally. This was new territory for me. I couldn't write back to Carl for several days, as I could not find the words that I felt accurately conveyed my thoughts and feelings. So one night I just sat down and typed what I felt:

Carl,

I have been trying to think of the right words to convey my thoughts on the overwhelming kindness you have shown me. I’m not a flowery guy, so I’ll just say thank you. I don’t mind going to work every day for guys like you.

I bet you were giggling as you read my earlier email. I wish you could have seen me as I unwrapped the mirror and tried to find the ding. I’m chuckling right now just thinking about it. I also wish you could have watched as I read your email and then ran downstairs and looked at the back of the mirror. The look on my face was that of an 11 year old opening his favorite Christmas present (a chess set, btw wink My Starmaster is complete again.

I hope you realize how much I appreciate your kindness. Truly warms my heart.

Tom

Here was Carl's reply:

Tom,

Once in awhile a situation comes along where I feel its a good thing to just take care of something. If you recall, I had asked specifically about your situation regarding your other telescopes, that is, if you had any, and so on. I did that for a reason which you're about to understand. What I remember you telling me was that you sold off all your other telescopes and toys, for the purpose of buying this Starmaster. And you didn't buy it new, which tells me this wasn't a "lark", and also that you're not one of these fellows who buys and sells premium equipment, changing it continually like socks. What all this says to me is you value our product beyond the norm. It means a lot to you. You sacrificed other things to get one of these, even though in a sense it was not generally affordable for you. So I realize how much it hurt when the mirror was damaged. This was your only "baby".

Because of what I've described above, Tom, you're the kind of customer that means the most to me. This was a situation where we decided to just take care of it and fix it for you. And yes, we giggled. We giggled a lot. You see, I didn't fix the break, as I indicated it was unfixable. Your mirror is a new one. That's why I said look at the (fabrication) date. It has the same serial number as your old mirror, only the date shows evidence of it being new. We were hoping that you would discover this on your own, as it might have been a fun surprise. But I think perhaps it is, anyway.

Once again, other than the coating, crating and shipping charges that we agreed on, "it on the house". And if you want to thank me, the way you can do it is put that new mirror to good use. Treasure it and take care of it, and keep it for as long as you look up into the heavens.

My fondest regards,

Carl


I still get goosebumps even as I am typing this up some 2 months later.

So, that is my Starmaster for life story. I asked Carl if I could tell this story in our words, and as one might expect, he said yes. I hope the email format was not too cumbersome, but I felt that the real exchanges between Carl and I conveyed the entire experience the best. If I could jump into your heart and let you feel how I feel, I most certainly would. Maybe just telling the story in our words will be enough to give you a hint of what kind of guy Carl Zambuto is.