There it is (left). Just look at it. It's the Princess and the Pea all over again. It's the straw that broke a few camels' backs. It's just a little piece of felt-like paper and yet it has caused some to contemplate sending their scope back and forevermore purchasing only TeleVue and AP scopes from that moment on. (*choke* *sputter* *gasp*) That little spacer will cost some people hundreds or perhaps thousands of dollars.

It doesn't have to be that way.

Just peel that sucker off, cut it in half and stick it back down.

It's as simple as that. Here are the steps to disassembling your 100ED and making the modification

Warning: Attempt this modification at your own risk. Performing this modification may invalidate your warranty. Andy accepts no responsibility for any damage you may incur during this procedure.

Step 1. Remove the lens cell from tube.

You need no tools. Just have someone hold the tube while you unscrew it. The lens cell will come off nicely. If it seems tough to do, just turn harder. Believe me, it will unscrew.

Step 2: Remove retainer ring.

You need to use a spanner tool to remove this ring.

I read one person's claim that the spanner tool you need to remove this ring cost $80. This alone seemed enough justification to suggest sending it back to Orion pronto.

Holy Guacamolies.

Please don't go out and buy an $80 spanner tool; and before you package your scope up for shipping, allow me to suggest a cheaper and less stressful alternative.

Step 2a: Build your own spanner tool.

Go to Home Depot or some other hardware store where they sell tools and buy a cheap spanner tool ($8 - $10) that has removable tips. Remove the tips for use on the new spanner and toss the cheap spanner tool into a drawer.

Cut a 1" piece of wood (preferably hardwood) to a length that is just wider than your lens cell. Measure the distance between the two holes in the retainer ring (photo above), and drill two holes about a half an inch deep to match the distance between the two holes in the retainer ring. Make sure that your drill bit is smaller in diameter than the spanner tips.

Voila!

Spanner tool.

You can pretend that you saved $70.

Step 3: Remove lenses

Very carefully, with a soft cloth in one hand to receive the lenses, turn the lens cell over and let both lenses gently slide out of the lens cell.

You must be very careful during this process to prevent scratching or getting your oily fingerprints all over the lenses. It's also a negative thing to drop them. Try not to.

You must also take care to mark the edges of the lenses to make sure you get them back together in the same orientation. Mine were already marked from the factory with a red pen.

Step 4: Remove the felt-like spacers.

I used a small plastic scraper to peel off the felt-like spacer intact. If you mess one up, no biggie. You'll still have two left to work with.

Step 5: Trim the felt spacers

Cut the felt spacers in half length-wise with an Exacto blade or a sharp knife.

Step 6: Clean your lenses and restick the spacers.

Chances are you got a fingerprint or six on your lens. I used InstaClears lens cleaner to get them and the gummy residue off the lens before trying to replace the spacers. InstaClears is designed to be used on lenses with coatings such as eyeglasses, camera lenses and scopes. I used the pre-packaged, pre-moistened lens towelettes. They are perfect for the job. They leave absolutely no residue.

Re-sticking the felt-like spacers can be a bit of a problem. They seem to be saturated with a waxy substance. I simply heated up the tip of an Exacto blade and touched it to the felt spacers. They stuck fine.

I sweated through the re-sticking process. Before I re-stuck the spacers, I used a micrometer to measure their thickness (.01 inch), just in case I screwed them up. My plan was to find a thin black material to replace them. Fortunately, I didn't screw them up. I had four good spacer halves to work with and they all stayed in place while I re-assembled the whole thing.

Step 7: Reassemble the lens cell.

Reassemble the lens cell in the reverse order that you took it apart. Just be sure you line up the marks you made earlier on the lenses before you replace the retainer ring.

Last night I took the 100ED out to Mansfield Dam for another star test and to get a host of second opinions. Richard Blake, our local expert from the Austin Astronomy and Science shop, took one look and immediately said "Tube currents. I'll come back later". Dave Rivenburg, a resident genius and avid astrophotographer said the same thing, so I contented myself with viewing at low power. Tube currents in medium size telescopes make little difference at low power. It's the high powers that bring out the worst in tube currents.

I waited on doing star tests in order to give the scope time to assume ambient temperatures. It came from a warm house and truck to the cold world that is Mansfield Dam. I usually don't pay a lot of attention to cool-down times with refractors because most of the time the difference between indoor and outdoor temperatures are not that great here in Central Texas. Since we were doing star tests, I needed to know that our results weren't being skewed by these tube currents. Tube currents can be worse in a closed system, such as a refractor, than they are in a newtonian. With newtonians, the issue is mirror cool-down..

I'll explain this phenomenon for those of you new to astronomy; a tube current is what happens when you carry a telescope from a warm house or vehicle and place it in a cold environment. Tube currents are actually a sort of "heat engine" inside your optical tube assembly. As your telescope begins to cool, the heat trapped in your tube rises pushing the cooler air down. The tube itself is still warm which then warms the air in the bottom and it rises to replace the air at the top which has now cooled a bit. This "current" will continue until the tube and the air inside the tube have assumed equilibrium. Depending upon the temperature difference when you started, this process could take over an hour, perhaps more depending on the size of the scope. A Newtonian telescope has an open top. The warm air simply escapes. The problem with Newtonians has more to do with the size of the mirror. Large mirrors hold a lot of heat and take much more time, sometimes hours, to assume ambient temperatures. And, like refractors, the larger the scope, the more time it takes to cool down. Check with your scopes manufacturer so see if a cool-down fan is available for your newt. Refractors will simply need to cool down on their own.

Ok. Back to Mansfield Dam.

Since we had to wait, I decided to play. Using a 24mm Panoptic, I moved the scope to Orion's Nebula. We had a lot of first-time visitors at the dam that night, so I had quite a few people come by to view the nebula. At low power, the 100ED sang like a phat (one must always use the politically correct term) canary. The contrast and crisp clarity is still a shocker to many. After I heard a dozen or so observers voice their "oooo's and aaahhhh's", I almost decided to give up on doing a star test. WHY Test? The views were beautiful!! But, for the sake of progress, I decided that I'd wait a bit longer, then perform the test.

I don't mean to beat this drum to death, but the Orion helical focuser is pure gold. I got quite a few compliments about mine. There were two or three people at the dam last night who went out and bought one based on my article. They felt like they had too struck gold when they finally obtained theirs. I think I'd best add an eighth point to my "7 Must Haves" article.

There were several experienced astronomers there to aid me in evaluating the scope. You know how it goes when you open your scope up to criticism from the big boys. They ALWAYS find something.

After two hours, Richard came back holding his TeleVue Nager 3-6mm zoom eyepiece. I thought to myself "oh geezz, I'm gonna catch it now." Richard, you see, thought I was out of my mind to take my lens cell apart to shave down those spacers. "NOBODY could even see those spacers unless they were so out of focus as to be useless as a telescope!!", he fairly shouted.

I chuckled.

He calls astrophotography "the dark side", as he winks at you. Richard is an observation purist. He is hilarious to listen to as he speaks of the "dark side", but a purist nonetheless. He placed his eye to the eyepiece and made those studious noises. "hmmmmmm" "ohhhh" "hmmmmmmm". He made them too long for my patience.

"Well???", I asked.

He looked up and proclaimed "Looks good to me. The seeing could be better for such tests, but this is about as good as we've had in a while, so be happy." Then he mumbled something about people tearing open perfectly good scopes.

The next to offer an opinion was Ralph Encarnacion. Ralph is one of the best astrophotographers I've ever known. You've got to check out his web site: http://www.pbase.com/panotaker/astrophotography. Ralph's comments were swift and straightforward. "Looks great to me, dude. That's about as good as it gets!"

Dave Rivenburg was busy contemplating some problem on his computer screen and preparing for a shot at the Horeshead. I had to drag him away from his task for a few minutes because I didn't want to leave without getting his opinion. He sat for a few minutes staring at my circles and then stated "It's off-center a tiny bit to the right, but not enough to warrant taking it apart again".

What??

Off???

I moved over to see what he saw. After staring at it long enough to almost burn those circles into my retina, I could see it. But, like he said, not enough to lose sleep over. It was almost imperceptible, so we called it good. We put in a 5mm Nagler and turned the scope to Saturn.

The proof IS in the pudding. Saturn was magnificent. The Cassini division was nice and crisp. We could even see a few moons!

I love my 100ED.

Andy.