
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.
The D1040Q diagonal is adjusted and 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.
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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) |
ADJUSTABLE ALIGNMENT? | NO | YES |
GLASS TYPE | H-K9L | LOW EXPANSION QUARTZ |
THERMAL EXPANSION | 7.1 X 10 (16)/K | 0.57 X 10 (16)/K |
REFLECTIVITY | 99% | 99% |
ACCURACY | 1/10 WAVE | 1/10 WAVE |
CLEAR APERTURE | 43 MM | 45 MM |
2" TIGHTENING | LEVER LOCK | LEVER LOCK |
1 1/4" TIGHTENING | COMPRESSION RING | COMPRESSION RING |
MIRROR REMOVABLE? | YES | YES |
RUBBER GRIP? | NO | YES |
MIRROR CUSHIONS | 1 | 5 |
WEIGHT | 17 OUNCES | 20 OUNCES |