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Home > Reviews > Telescopes > Newts > Webster Telescopes ”28” f/4

Webster Telescopes ”28” f/4
By Dave Bonandrini - 6/27/2006

For those of you who don’t know me, I build large Dobsonian telescopes as a hobby. My definition of large is 24” and up. I teach telescope building classes that emphasize the reasoning behind doing something a certain way, rather than just following a set of plans. I consider myself a more than competent woodworker. I am an AstroMart Moderator, and I currently use a 30” f/5.3 Dobsonian telescope that I designed and built myself. The largest telescope I have built is a 36”. I have owned or used almost every brand of Dob in the world, and then some.

There has to be at least two dozen telescope companies making their own versions of the 20 year old classic Obsession telescope. While the original Obsession has remained basically unchanged, the clones have come out with all sorts of twists in both design and materials. You can get an Obsession clone made from fiberglass, carbon fiber, honey comb cardboard, hell; you can even get a clone made from aluminum. Every manufacturer has had some trade offs that have kept it from overtaking Obsession. Starmaster had better optics, but was heavier, and took longer to set up. Tectron had really nice hardware, but its tiny altitude bearings left you adjusting counterweights all night. Nightview looked like it was part of the Hubble, but you could put your ear to it and listen to it ring.

With the recent Pyrex panic that has taken hold of the hobby, I have had to accelerate my plans of buying of a new mirror for my next project. I had been considering something like a 36” f/5 for a few years. I have never liked fast mirrors. I don’t like stars at the edge of the field that look like seagulls. I don’t like having a big, honking coma corrector hanging off the focuser. And, I don’t like the generally poor performance of fast optics. I have always believed that big optics mean big scopes. To paraphrase B.B. King; “You have to pay the costs to own the boss”.

Last year, at a gathering in Florida, I experienced a paradigm shift. I took a look through a telescope that had a Steve Kennedy mirror in it. Steve Kennedy’s claim to fame is really fast large reflector optics. I remember the scope as being a 28” f/4, but others have latter insisted that it was a 28” f/3.6 that I had looked through. The scope itself was not up to my jaded standards, but the optics blew me away. Not only was this a very fast mirror, it gave me the best star test I had ever seen! Essentially perfect. Those of you who know me, know I don’t make statements like that often, if ever. My life long mindset was now in disarray. It appeared that fast optics were the not the problem, poor opticians were the problem. What if I didn’t need to haul around a 10’ ladder all the time? Would I see a real difference in the wider field of view? Would I be giving up anything optically for this shorter telescope?

TRYING TO DO A REVIEW

A few weeks ago an online thread was started entitled “Has anyone seen a Webster Telescope”. Different people stated that they had or had not, but everyone wanted a real review. In the past I had bought truss clamps from Webster, and one of the family, Eric Webster, lives not too far from me. Here, I felt, was my chance to take a detailed look at a Kennedy optic and write another of my wordy reviews....or so I thought. When I called to offer to do a review, Eric said a moderator from CloudyNights had emailed him about someone doing a review. At the same time another reviewer from a magazine wanted to do one too. I told him “c’mon, those guys have no experience with really large telescopes, you need me to do it “. He said thanks but no thanks, and that they currently were making as many scopes as they could get optics for. He further stated that I was welcome to come by anytime and observe, I didn’t need to take a scope.

A week or so went by and I called them up to see if they would cast an odd size aluminum altitude bearing for a guy in the club. I found out that no one had reviewed a scope yet. Having heard that Eric was an audiophile, I played my trump card. I offered to lend him a pair of Martin-Logan Prodigy speakers and a pair of Halo JC1 amps to “review”, while I reviewed a telescope. He took the bait and the next day we drove my van to their dark site to pick up a scope. The things a guy has to go through to test out a telescope...


Cooling off, while the scope cools off.

FIRST IMPRESSIONS

I was fishing around for adjectives to describe the overall appearance of a Webster Telescope, but I think my neighbor may have hit it right on the head when he asked over the fence “Ikea making telescopes now?” At first I didn’t catch the reference, but he’s right, they look European. The black and birch style would be right at home in the House of Denmark showroom.

Clean would be another fitting adjective. Even with this scope being completely “tricked out”, it looked uncluttered. Take a look in the photo section of the Servocat Yahoo Group (http://groups.yahoo.com/group/ServoCAT/) to see what a mess most telescopes look like with the Argonavis/Servocat combo installed (my own scope included!).

All and all I would describe it as a distinctive, European looking scope.


Long handles make it easy to move this scope around. The all black hardware is in stark contrast to the light wood.

ROLLING IT OUT

I started setting the scope up a few hours before sunset, to make sure that the mirror would have time to cool down from the hot vehicle. The wheel barrel handles for the scope are really long, as in 10’ 7” long! They stand off the back of the Rockerbox by almost 7 feet. At first this seemed excessive, but I’ve got to admit, it was much easier to move this scope with the additional leverage, than my own scope. The handles are made of square tubular steel with 13” pneumatic wheels.

After parking the scope, you remove the wheel barrel handles by spinning off 2 large steel eye-bolts. These eye-bolts are captive and stay with the handles. This will be familiar to anyone who has seen the older Obsession telescopes, before they switched to the breakable plastic knobs.

To assemble, you place the 4 truss pairs into the clamps, and then you climb up and drop the UTA on top of the 4 UTA clamps. Spin the scope while you are up on the ladder to tighten all the clamps, and you are done. Takes 5 minutes, tops. It was refreshing not to have the trusses flopping in every direction when up on the ladder. Everything was dead on, no rings, or place holders were needed. I discovered an even easier way to set up that I will describe latter in the review.

GROUNDBOARD

The Groundboard is made of plywood. The scope came with the Powered Groundboard option. This allows the battery to remain far from the telescope, and keeps the power cord from tangling around the scope as it rotates. The supplied power cord is a heavy, 12 gage “outdoor” power cable. The cord is reverse wired (I guess to keep someone from accidentally plugging it into an 110v wall outlet). The stated reason for this is to allow you to use any heavy duty extension cord to increase the distance between the scope and power source. They supply a pigtail with either battery post terminals, or a cigarette lighter end. I chose the terminals for use with my marine battery. The pigtail is fused (10 amp) at the battery.

Remember that lead batteries (yes, even “sealed” or gel cell batteries) discharge corrosive gasses while being used. Never keep a battery mounted in your Mirrorbox or Rockerbox, unless you are in a hurry to get your mirror recoated.

Eric made a point to say that they only make round Groundboards. It is surprising how many triangular Groundboards are out there. It may save a little weight, but if you ever want to add a GOTO system, you have to buy and install a whole new Groundboard.



The Rockerbox is very low profile. Note how clean the wiring install is.

ROCKERBOX

The Rockerbox is a very low profile design, and is chock full of wires, switchboxes and motors. The Mirrorbox just barely clears all of this inside gadgetry. Obviously these clearances are all designed by computer, because it just looks like its not going to have room to clear. Will you notice the savings of an inch or two in height and a few pounds of wood? I’m not sure I did, but somebody might.

The 12v wiring is again 12 gage, 20 amp wire that runs to a switch box. The switch box controls: fan 1, fan group 2, the Argonavis and ServoCat (both switch on together to avoid current running through the Argonavis; causing it to burn out). I’ll cover the fans in a latter section. All of the wiring is stapled or zip tied down to the floor of the Rockerbox. The moving wiring harness that drops out of the Mirrorbox is wrapped in plastic wire loom to keep it from snagging and abrading.

The outside of the Rockerbox is covered in a synthetic material that is normally used to cover the speaker cabinets of touring bands. At first I thought that this was rather odd, but this telescope is 2 years old and the Rockerbox looks brand new. I’m sure I will “steal” this idea for my next telescope. It’s one of those “Why hasn’t anyone else thought of this?” ideas that obviously works much better than a scratched and dented box. What’s next, a scope with metal edge guards and corners?

The bottom of the Rockerbox is completely covered in fiberglass reinforced Glassboard.


MIRRORBOX

The Mirrorbox has conspicuous dovetail joints running down its corners. Being a weekend woodworker, I love to see dovetails, as they are, by far, the strongest (and most beautiful) wood joint. I cut mine by hand, but these are obviously cut by a CNC mill, as they have that “perfect” look to them. Everyone I showed this scope to was “wowed” by the woodworking. The wood finish was flawless, minus a few scratches, normal for a 2 year old scope. I would describe the clear coat as a satin finish, which has been waxed or rubbed. If you put a slab of marble on top of this Mirrorbox, you could use it as an end table in any living room. The finish is that good.

The Mirrorbox is remarkably small for a telescope of this aperture. For instance, their 28” Mirrorbox is actually smaller than a 24” Starmaster mirror box! Between their low profile Mirrorcell and their mounting of the truss clamps on the outside of the Mirrorbox, they really trimmed the fat in this design.

The light baffle at the front of the Mirrorbox is finished in what looks to be black epoxy. Black is definitely the proper color for a light baffle. I agree with their web site; I’ve seen too many telescopes where the light baffle is glossy, light colored wood, or even painted with glossy paint. Put those in the “What were they thinking?” file. I know the light baffle is normally covered by the shroud, but I did find a few, very small “fisheyes” in this epoxy finish. Usually these are seen when some small contaminant is under the coating.

One thing I felt was missing was a rear light baffle. Not all of us are lucky enough to do all of our observing under dark skies. Sometimes light reflects off the ground and up into the scope, especially if you are forced to set up on concrete (heaven forbid!). Why not add $50 to the price of the scope and supply one, or at least make it an option?

The Mirrorbox cover is a round disc of ¼” Baltic Birch 5 ply plywood. It is secured to the Mirrorbox with Velcro. It could actually use a little less Velcro, as it was hard to remove. If this was my scope, I would trim it back 30%. The knob in the middle is the same knob used on the UTA clamps and the mirror cell. If you ever lost or damaged a knob, you could use it as a spare.


The Mirrorbox is heavily reinforced. I had to crank up the contrast to show this clearly.

Inside the Mirrorbox, there are gussets running the full length of the joints. Also there are 2 braces per corner. These braces are rather oversized with big holes cut in them to allow warm air to travel away from the mirror and, I suppose, to save some weight. The finish here is the standard flat black paint you would expect to see.

There was no perceivable play between the Mirrorbox and the Rockerbox sides. If I really tried to force the Mirrorbox to move sideways, totally unrealistic to the way one would actually use a scope - I know, I could get about a 2mm gap.



The Encoder is hard to see, but its shaft is installed inside the bearing itself.

ALTITUDE BEARINGS

The Altitude Bearings are made of lightweight, cast aluminum. This probably shaves 30 pounds off the weight of solid plywood bearings. The sand used to cast these bearings is very fine, much finer than the sand used on my old Obsession scope. The bearings have a flat black anodized finish that matches the rest of the scope nicely.

Because they cast their own bearings, I asked why they make them a half circle, when the rear 20% of the bearing never gets used. Eric said that the Servocat requires that back piece, otherwise you have to put in a little “pie slice” to make up for it. So now I know…

An interesting part about these Altitude Bearings is that the DSC encoder mount is machined right into the true center of the arc. No adjustment is necessary to get it right. This also shaves about an inch off the profile of the scope and makes it less likely you will smash the encoder while unloading. The encoder hardware is free on the Rockerbox end so you don’t have to remove or loosen the encoder bracket before traveling. Normally, if you forget you left the encoder arm locked down, a hard bump on the road could destroy your $90 encoder. If I had one suggestion here it would be to add an actual guard bracket over the encoder, I’ve never seen that on any scope.

The encoder is mounted on the non-focuser side, opposite the conventional placement. They reason this is the safer side, away from ladders and observers. More sound advice for you ATMs out there.



Mirror cell ready to be shipped out. Photo: Webster.

MIRROR CELL

The mirror cell is one of the most innovative parts of the entire telescope. It is both very compact and very low profile, which in turn, allows for such a small Mirror box. I found the cell to be very open to air flow. The main frame of the cell is tubular steel. The welded joints look clean, with a very small amount of splatter evident. The cell is painted flat black.

The 28” was using an 18 point cell. Each triangle is 1/3” thick aluminum with a stainless bearing bolted to each corner, giving ¼” of clearance for air to travel beneath the triangle and across the rear mirror surface. A stainless steel stud runs through each triangle and into a spherical bearing that is pressed into a 3/8” steel bar. (A spherical bearing is a type of joint that allows free movement in any direction. The bearing is lined with Teflon to keep things moving smoothly.) This bar in turn, has a larger spherical bearing set in its center that receives the collimation knob, used to adjust the aiming of the primary mirror. Every single moving part of the Mirror cell floats around on these bearings. The joints move so smoothly that it takes maybe 10g of force to move them, with no breakaway “stiction” evident. I do not exaggerate when I state that you can blow on these parts and get them to smoothly move! No pictures I took were able to show this range of motion. I would literally have to make a movie clip (That’s a hint to the Webster Telescope webmaster) to do it justice.

The triangles are kept in alignment with a thin stainless steel wire. I usually see this alignment done with a wide plastic ring. The wire would allow much more airflow, another nice idea, showing that they are “in tune” with the time it takes to cool down big optics.

The adjustment of the primary mirror takes place using 3 large knobs that spin on some finely threaded stainless rods. The cutting of the threads was well done, as the knobs had a very precise feel. These large knobs would be easy to use with gloves on, a tip other manufacturers should note. The knobs were correctly installed with the 2 knobs you always use on top; where you don’t have to reach down to use them. The seldom used single knob is on the bottom.

The Webster’s are big fans of gluing down optics to avoid using a sling for lateral mirror support, but this scope came with a stainless steel cable sling. Cable slings have been around for a while, but this is the first time I’ve seen one come factory installed in a commercial telescope. Cable slings became popular because they don’t put stress near the face of the mirror and they do not stretch or shrink after sitting in the hot sun all day. The thin cable allows 100’s of times the air exchange over the fabric blanket that a conventional sling provides. The sling is adjusted by hand, no tools (other than a measuring tape) are needed, but realistically this will only be done once at the factory.

The cell is bolted to the Mirrorbox with 12 stainless steel, flush head bolts.

The cell is designed to always have the mirror installed, even while transporting and washing. This is a good thing, as the mirror weighs 90 pounds.

I was thoroughly impressed with the Mirror cell. I think the other companies that are still using acorn nuts and rod ends have much to learn from the elegant simplicity of this design.


The fans are suspended for vibration control. It’s hard to see in the picture, but every joint above is a spherical bearing. Note how open the cell is to airflow.

FANS

The fans were new models that a customer had sent to Webster for them to try out. They had not even had them out under the skies yet, so they asked me to run them through their paces. Eric said if they work out, they might become his “super fan” option.

The fans were 5” square and put out a lot of air. Kind of like a computer “muffin” fan on steroids. They were set up so that the “Fan 1” switch turned on a single center fan. “Fan 2” turned on three peripheral fans. Each fan was suspended on rubber rings to minimize vibration. With all the fans running, I was feeling around the mirror to see if air was getting under the triangles and out to the edges of the mirror. Air was indeed moving over the entire mirror surface, a sign of good design, and powerful fans. For deep sky I could leave all of the fans running, but for higher power viewing, I used only the single center fan.

While slewing the scope around by hand I accidentally touched one of the fan blades; “ZZZZPT!!”. I yanked my hand back, unharmed, but it still scared the crap out of me! How hard would it be to put some grills over the fans?

Otherwise, I liked these new, high powered, but quiet fans. It would be interesting to see if they still run as quietly 1000 dewy hours from now.

The mirror box had mounting holes where I assume front “boundary layer” fans were at one time installed.



Truss clamps and pins. Nice dovetail work and stainless bolts too.

TRUSS STUFF

The truss clamps were well made, with an actual pinned hinge, rather than just trying to flex wood or metal. They are open at the bottom allowing all of the UTA wires to run cleanly up the trusses. This is another case of “Why don’t all manufacturers do this??”. Webster supplies a nylon monofilament that quickly “fishes” the whole wiring harness right up the truss; nice touch.

The bottom of each truss sits on a pin for repeatability. This pin can be removed if you wanted to make the trusses shorter, without actually cutting the trusses. Apparently some customers have drilled small holes in the side of the trusses to allow a two position system, by placing the pin in the hole. This would benefit astrophotographers who would otherwise need to buy a second set of poles. I like this feature a lot.

The trusses themselves are anodized flat black. They look very “finished”. All of the trusses except the electrical conduit truss, are somehow internally deadened for vibration and capped. I liked the caps because they keep dirt, mud and wasps from filling the ends of the trusses.


At the end of the V-slot is a machined socket that the t-bolt drops into. The t-bolts are labeled so the scope assembles the same way every time.

The UTA clamps pin the two trusses at a single point, thus making this a true truss system. The knobs are captive to prevent removal or loss. The knobs connect to a T-bolt that locks into a socket milled into the bracket mounted to the UTA. As far as I know these brackets are not sold separately by Webster, or I would have bought them in the past. They should offer them, as it is one of the few positive locking systems I’ve seen. There is no way for the bolt to slip out of or rotate in the slot.



The inside of the UTA is actually FLAT black!

UTA

The Upper Tube Assembly is maybe one of five in existence that does not use shiny Kydex or ABS plastic as its internal light baffle. Kydex is a thermal plastic that has a shiny, “haircell” finish embossed on one side. For almost 20 years this stuff has been scattering light into eyepieces around the world; it just won’t go away. What Webster used here is aluminum, with a plastic coated black exterior and a flat black interior. I would think that in the long run the aluminum may acquire a few dents, but Kydex deforms in the hot sun, so I’ll call this one a draw on longevity.

I like to “twang” the vanes of the spider to see how tight they are drawn. A properly tensioned spider has a higher tone (don’t be afraid, you can put a lot of tension on a spider). I was surprised when the vanes made a dull “thunk”. I looked closely, the first thing that came to my mind was carbon fiber, but the vanes were actually stainless steel with some anti-vibration pads hidden in the shadow of the secondary. I was starting to see a theme here with all this anti-vibration technology.

The 5” secondary mirror had a dew heater installed with a detachable plug. The vanes themselves are the negative conductor and the positive conductor is brought across with a thin foil strip. No wires cross the light path, very nice.

I’m a big guy, but I would say that the 28” UTA is about the limit of what I would climb up a ladder to place on top of the trusses. Its not that it weighs all that much, the UTA is quite lightweight, it’s just how bulky it is. Webster has installed a second lock nut on the secondary holder, allowing you to install the secondary in the exact same place every time it is removed. Slide it in and spin a wing nut on the top. I tested this feature with a Cheshire, and indeed it was dead on. This is a great idea that every manufacturer could steal (adopt?) for about 50 cents. Because the secondary is the heaviest part of the UTA, Eric says he always installs it after the scope is assembled, he is not as big as me ;-) .

The trusses and hardware are so rigid that I found that if somebody tilted the scope down towards me, I could easily install the entire UTA with both feet on the ground! So if you are observing with a partner, my advice is to skip the ladder altogether.

Webster has placed a laser target opposite the focuser so that the “squareness” of the focuser can be checked from time to time. The always excellent Feathertouch focuser has the adjustment screws in its base to fix this.


Detail of UTA. Note red arrow showing laser target.

The Argonavis DSC was installed next to the focuser with a large square of Velcro. On top of the Argonavis was the Servocat control pad, also secured with Velcro. The Telrad finder had a “patchbay” with 4 phono RCA plugs supplying 12v to the eyepiece dew heaters, Argonavis and the secondary mirror. Too bad the Telrad was not itself powered by these connectors, I checked, it was still using batteries. I applaud Webster for only installing Feathertouch focusers, they are indeed without equal.


Velcro straps make the shroud fit properly.


LIGHT SHROUD

How much can be said about a light shroud? Plenty if it actually fits the telescope. The problem is a catch-22. Stretchy materials let air and light easily pass through them, so your body heat gets into the light path. Rip-stop or parachute nylon is good at blocking air currents and light but is really hard to fit onto the scope because it has no “give” to it.

Webster uses Velcro (they must own stock in the stuff!) straps to gather the Rip-stop nylon under each of the truss clamps. In the front of the scope they get around the altitude bearings with a slot sewn into the fabric, and of course more Velcro to close it back up. The shroud slides right on, with no headaches. The UTA half of the shroud pulls tight with a drawstring. Why can’t all shrouds be this easy? Maybe they can start selling aftermarket shrouds for the rest of us.


A slot in the shroud wraps around the altitude bearings. Photo: Webster.

ACTUAL USE

I habitually reached for my 10’ ladder, laughed to myself, and took out a 6’. The 6 footer was all I needed, but if I were taking this out to the public, I would use a 7’ so the children could see at zenith too.

The next hardest thing to get used to was how wide the field of view was. After so many years of using my 17mm Nagler, I know what M13 looks like right? Nope. I actually looked up to make sure I was in Hercules; there was just too much field around it. NGC 6992 (the Veil nebula) had so much more to see at one time it was amazing. Even more so than a short ladder, the field of view is what the selling point should be on these scopes. Amazing.

I had taken a Paracorr (PARAbola CORRector) to use in this review, but I found I used it less than I expected. Just for a test, I used the 31mm Nagler both with and without the Paracorr. Without, I could see that the outer 20% had obvious seagull looking stars. With, the whole field looked like I had just dropped into space. As an aside, the 31mm Nagler has an exit pupil most likely too large for older observers when used in this scope, so although fun to play with, some of the starlight is wasted. With the 17mm you could really almost get by without the Paracorr, especially if you are using an OIII filter, because the filter makes the stars look odd anyway. The 26mm Nagler needed the corrector.

The Denkmeier Binoviewers needed no Paracorr at all because the OCS module at the front is a corrector. Here again, my whole reality was messed up as I had to become reacquainted with old friends, in much wider fields. Jupiter was killer in the Binos, details galore.

Usually at this point in a review, the reviewer lists about 5000 objects they observed with a description of each. I would never bore you with such a list. Suffice it to say, the Kennedy Optics package was incredible. I understand that Webster has an exclusive deal with Kennedy that they purchase the exact secondary that was used to put the final figure on the mirror. I’ve never heard of anybody taking things that far, but I wish everybody put that kind of concern into the optics package. While the skies were never steady enough while the scope was in my possession to do a really critical star test, I can state that this mirror was free of any astigmatism at any power, and the star testing I was able to do was simply stellar. Cooldown was about an hour to an hour and a half, but your night temperatures may not drop as rapidly as mine. Some of this quick cooldown credit goes to those big fans, so if Webster does not end up using them, take the whole thing with a grain of salt.

On the last day before having to return the scope, the Servocat goto died. It was still lit up, but refused to follow any goto or directions. I swapped hand controllers with my own but it was still dead. This left me with only the Argonavis and my own two hands. Even though anyone with a telescope this size is going to have goto, this did give me a chance to test how smooth the scope would run in old school manual mode.

The scope was very smooth and easy to move; even Dobson’s Hole was easy to navigate. No counterweights were necessary when moving from the heavy binoviewers to a 7mm Nagler, so that shows that the Webster’s can use a calculator. Pushing the scope up or down in altitude then letting go shows the scope is just slightly bottom heavy; nothing a dew laden shroud can’t fix.

I did not get to test out their ACDS electronic vibration countermeasure device. I was not allowed to tour their woodshop either. Eric said they were not insured for the public to be running around in there, I think they are hiding something….

SUMMATION

Usually in this part of the review, the reviewer tries to find a number of positive points and balance them against an equal number of negative points. That way it looks like an unbiased review. That seems silly to me. I’ll just wrap it up for those of you who did not take the time to read my whole review: The Webster Telescopes 28” F/4 Is a really well designed telescope with really great optics, which needs a rear light shield and some fan guards.

Are they “the ones to beat”? Currently I would have to say yes, but ask me again a year from now. This hobby can always use more innovation. Not just changing things to make a scope look a little different, but changing things to make it better. They have implemented some very clever ideas that made me more than a few times ask myself “Why didn’t I think of that? Why hasn’t ANYONE thought of that?”

Will they one day unseat Obsession? No way. From what I understand Steve Kennedy works all by himself. There is no way he could ever make the 100 or so mirrors that Obsession sells every year. Worse yet, he could become injured and production could cease entirely. With Carl Zambuto not making any large optics, where would these other ultra-premium star tested optics come from? Certainly not from some huge mirror factory or the Far East, that’s for sure.

Are you giving anything up optically by going with such a fast mirror? A year ago my knee jerk reaction would have been; of course. But after getting some actual experience with these optics, I feel the wide field of view more than makes up for any shortcomings requiring a Paracorr. You will be surprised at how few eyepieces in your kit even require any correction. Sure, there are people who use a Paracorr even at f/5 and spend the night studying the edge of field. But I’d be willing to bet 99% of the people will find these optics the best they have ever seen. All of my fellow astronomers who looked through the scope could find no fault with the optics. If fact, if I purchase a mirror, I will go even faster to f/3.6 in order to gain an even wider field of view. How’s that for a vote of confidence from a lifelong f/5+ snob?

So, it has been 20 years since the Dobsonian revolution, and this appears to be the state of the art. I can’t wait to see what the next 20 years holds for us.


Clear Dark Skies,

Dave Bonandrini 6/24/06


Webster Telescopes responds:

Thank you Dave for the big review, I hope they paid you by the word!

The small fisheye flaws are because I had at one time had flocking glued to the baffle. The dew and frost took its toll and I pulled it all off and refinished it. If this scope was going out to a customer, I would have rubbed them out. For our own use, it is good enough.

I credit the clean look of our scopes to the fact that this is our 3rd generation telescope. The ServoCAT and ArgoNavis were already on the market when we designed our “C” series, so it only made sense to design around them.

I read to my grandmother, who designs and sews our shrouds, your review of her work. She laughed and said “Never let a man do a woman’s work”. You made her day.

Lastly, the SevoCAT appears not to be at fault for the problems you experienced. One of the groundboard carbon brushes shattered preventing enough voltage from reaching the poor Cat. I set a new one in the sleeve this afternoon and all is well.

Thank you again,

Eric Webster
Webster Telescopes
www.webstertelescopes.com

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