William Optics ZenithStar 105 Ed Triplet APO

Since entering the hobby of astronomy about 4 years ago, I have had my fair share of telescopes. Most of my scopes were reflectors with the exception of a ST-80. I spend 90% of my time under the stars imaging with film. Since film was the medium I chose to photograph the night sky, fast focal ratio Newtonians fit the bill best for me (and my pocket book). I have spent about 3 years shooting film with my F/4 10” Schmidt Newtonian. This scope provides a huge field of view and, fairly quick exposures (15-50 minutes) for most objects. It also requires almost continuous collimation, and long cool down periods. Although the Schmidt Newtonian is well corrected for an F/4 it still shows a fair amount of coma, especially on a 35mm frame. Having become satisfied with what I have done with this scope, I began to look for a scope with a flatter field, still relatively fast and of course reasonably priced. Enter the word “APO” and exit the words reasonably priced right? Well, at first glance of the APO market reasonably priced is not the first thing that pops into your head. I wanted quality fit, finish and optics. I love the Tak FS 102 but if I was to buy that I would be single (not necessarily a bad thingJ) but, my lovely wife would take the Tak, and all of the other goodies with her. Then I remembered seeing a William Optics Megrez riding piggyback on a SCT at the Cherry Springs Star Party. I recalled standing at this gentleman’s setup for about 2 hours that day admiring the pure beauty of the Megrez. He had nothing but good things to say about the scope. So, I checked out Anacortes to see what William Optics had to offer in the 4” APO range. There she was the ZenithStar 105 ED triplet. I started to read the specs, 105mm ED air spaced triplet, 360 degree rotating 2.5” Crayford focuser with 10:1 reduction, focus calibration scale on the drawtube, retractable dew shield, and a water resistant case. All for under $1700.00! I was shocked, even more so when I noticed that William Optics also offered a package deal. For $300.00 more you get the 2” dielectric diagonal, a pair of mounting rings, a red dot finder, and a nice aluminum case. Being the Newtonian junkie that I am this seemed like the perfect cross over deal to me, since I don’t own a diagonal, and would need to purchase mounting rings as well. After convincing the wife that this was the one, I set out to order the ZenithStar 105. Anacortes, did not have one in stock (SHOCKED) and I could not find one anywhere on the net. I then called William Optics to see if they could tell me when they would be available again. I spoke with David, a very knowledgeable and no nonsense guy, courteous, straight forward and best of all he made me feel comfortable making the purchase. I can not say enough about the customer care that William optics has offered, I say customer care because that is what it is. I genuinely believe that William Optics puts the customer first. Many people in the W.O. Yahoo group have said a few weeks after their purchase they received a letter thanking them for the purchase. When, outside of buying a new car have you last seen or heard of anything like that?


Waiting for UPS to show up with the new scope felt like months, but it was on time and I received it a week later. The scope was packed very, very well. Opening the outer box, revealed another box (who would have thought?) this box was adorned with a big red swan, the W.O. logo. I then tore into the box inside the box (out of the box thinking) to find a layer of protective materials ,( ya know the little bubbles that you just can’t help but to pop) and the 2” dielectric diagonal, rings, and red dot finder. The diagonal is a real piece of art, the rings are top notch, and the finder pretty cool looking. Then under a layer of heavy brown paper was the shiny chrome looking aluminum case. I set everything aside and yanked the case out like it was the last Cabbage Patch doll in the store on Christmas Eve. For the record I have never done that! The case is substantial, and has a very nice Swan logo riveted to the top. Now I am holding my breath as I release the two clasps that are standing between me and Black Beauty. I can’t tell you the first words I uttered, but wow sums it up nicely. The black and gold contrast are just awesome. The slick anodized tube was immaculate. As I picked up the scope I was shocked to feel how substantial it is. All of 9 lbs. A quick check of the objective showed no signs of damage, the coatings looked good, and the baffles look very good as well. After I realized I had been racking the focuser in and out for about 10 minutes (mesmerized by it’s smooth feel) I ran out to the observatory to mount the scope (on the pier). The saddle plate I had available is too long to get a good balance with the 26” with dew shield extended scope, 23” with it retracted for those of you taking notes. So I had to resort to piggybacking a ST-80 on the ZenithStar to balance the rig. The W.O. rings are truly a great piece of work, black powder coat finish with a Teflon bushing under the securing bolt. I slide in the 2” dielectric diagonal, and secured it with the compression ring. By the way the scope comes with a 2” and 1.25” compression ring as does the diagonal. Next thing I did was to remove a small Allen head screw from the rotating focuser body to install the red dot finder. Again I found myself marveling at the smoothness of the rotating focuser, and in my opinion it was a nice touch to mount the red dot finder on the focuser body. As you turn the focuser to accommodate odd viewing angles the red dot finder goes with it.

First Light:

Well the weather has been terrible for a long time. I was able to beat the new scope curse as I had mostly clear skies the day I received the scope. Luna was flying high and bright, a good target to check color correction. To make a long story short I gave the ZS 105 all the power I could muster and only after stacking a 2X Barlow and a 2.5X Power Mate with a 6mm plossel could I see any evidence of color on the moons fringe. This color was not obtrusive, and rippled with the seeing. Just to be clear here, at any magnification that the seeing would support I saw no color on any object. Seeing was not very good but I tried a star test which appeared to show that collimation was spot on, so no fiddling with the adjustable lens cell. Focus was very evident as I got that “snap” that all the refractor guy, and gals talk about. Really the only negatives I could find with this scope were that I need an extension tube to reach focus with my DSI and my 35mm camera. A quick click here and there at Anacortes will get me the William Optics extension, and probably the .8 reducer/flattener.

Conclusion:

In closing I would like to thank William Optics for producing such a beautiful, and well made APO that is affordable (in APO terms). I would recommend this scope very highly. It is built to near perfection. Also thank you Astromart for giving us amateurs a place to post reviews on products that we love or hate. In this case I am in love!