This is the most advanced version of our most popular diagonal. It was designed by Vic Maris and uses a thick, over-sized mirror polished to 1/10th wave low expansion Quartz mirror. The mirror has a protective, dielectric coating with 99% reflectivity. It has a compression ring eyepiece tube and the insert tube has a bevel that will better seat the diagonal in the focuser. The FA-002 deluxe 1.25" compression ring adapter is included. Both the two inch insert tube and adapter have filter threads. A rubber grip on the 2" tube allows for easy handling in cold climates. The 2" female insert tube on this diagonal will accept 41mm or 1.61" of nose piece length before hitting the built in safety stop. If your 2" nose piece is longer than this specified distance, the nose piece will not fully insert, though this is rarely an issue. The D1040Q adds 4.1" or 104 mm to the optical path. These diagonals are assembled, adjusted and double tested at Stellarvue for perfect alignment and performance. The five point cushion system eliminates pinching in all climates and the precision CNC machined components assure perfect alignment that stays that way. The four point adjustment allows us to perfectly align the mirror so every diagonal that leaves here is perfectly aligned.
This new version has additional improvements. It is now made with a low expansion Quartz mirror to maintain optical accuracy as the temperatures drop. The main body is cnc machined from a solid piece of aluminum. The eyepiece and insert tubes are identical to the original non-quartz version featuring a tapered safety on the nose-piece, a brass compression ring on the eyepiece tube and a rubber grip.
Star diagonals are a critical component of any refractor. The performance of an otherwise excellent telescope can be seriously compromised using a diagonal that is misaligned or pinched. We researched diagonal design and fabrication for two years before introducing our first 2” dielectric diagonal. We studied more than 20 diagonals on the market and discovered that 18 of them were either misaligned or pinched! This causes astigmatism and reduces optical performance.
Each diagonal and erecting prism we sell is tested for alignment and will preserve the exceptional quality of your Stellarvue telescope. Since the D1040Q is adjustable, it is the most accurately aligned diagonal we offer.
|Vic designed this over a two year period with the goal of ensuring a perfectly aligned, non-pinched system.||The dielectric coating reflects 99% which means brighter, higher contrast views.|
The D1040Q is cnc machined from a block of solid aluminum. The 2" tapered insert tube and the 2" compression ring eyepiece tube are cnc machined in our shop in the USA with an over-sized threads for a slightly wider clear aperture. The biggest difference is our ability to dial in alignment so it is precise. Misaligned star diagonals cause on-axis astigmatism degrading the performance of your otherwise perfect optical system.
Several years after you purchase your D1040Q Star Diagonal you may want to remove the mirror to clean it. You may do so with Acetone following the directions we provide. We will soon offer a video showing how this is done and what makes the Stellarvue Star Diagonal the one to have!
Here is a comparison of our D1040Q star diagonal compared to our import diagonal the D1028ECF. Notice that the Quartz mirror expands and contracts up to 12 times less than the standard H-K9L glass. The Quartz mirror remains stable under extreme temperature changes!
|SPECIFICATIONS||MODEL D1028ECF||MODEL D1040Q|
|ASSEMBLED IN||CHINA||U.S.A. (STELLARVUE)|
|GLASS TYPE||H-K9L||LOW EXPANSION QUARTZ|
|THERMAL EXPANSION||7.1 X 10 (16)/K||0.57 X 10 (16)/K|
|ACCURACY||1/10 WAVE||1/10 WAVE|
|CLEAR APERTURE||43 MM||45 MM|
|2" TIGHTENING||LEVER LOCK||COMPRESSION RING|
|1 1/4" TIGHTENING||COMPRESSION RING||COMPRESSION RING|
|WEIGHT||17 OUNCES||20 OUNCES|
3 Reviews Hide Reviews Show Reviews
Very nice piece of maching work, fits snug and works very well.
High quality product, excellent results.
. The Stellarvue diagonal D1040Q was received very well packed for safe arrival. It came with an excellent adapter to allow the use of both 11/4" & 2" eyepieces. It comes with an instruction booklet. Evaluated using my Stellarvue SV115T20 apochromat. The diagonal is sturdily built and very high quality. Straight through performance with eyepiece versus eyepiece + diagonal indicated no loss of performance either in brightness or sharpness of image, high contrast levels retained. Eyepieces used FUJIYAMA HD-OR25mm; PENTAX 20mm & ED5.2mm. The jewel box and Jupiter were used in the evaluation. Air temp 10 degrees C. Jupiter showed a wealth of detail including the giant red spot and 4 jovian moons,as tiny orbs. The jewel box was ultra sharp with the individual colour of the stars of this compact cluster very clear and distinct with beautiful contrast. I can highly recommend the Stellarvue D1040Q for those individuals seeking a no compromise diagonal for use with the highest quality instruments and eyepieces.