Had a great night out with the SVX140 in Torrey Utah. A new friend had their TEC140ED. Our VRBO host mentioned they had a guest at another one of their properties who was in town for the same reason as we were, so we connected and agreed to meet. Interestingly, we both had a Planet with an extension, my DM6 and her AZ100, and the same diagonal, so the comparison was on a truly level playing field in that regard.
First let me say we didn’t account for the small f/l difference (938 vs 980) in other words we didn’t attempt to perfectly match magnifications. It was close enough however, and I can’t imagine the small difference had any bearing on our impressions of the scopes. The eyepieces were mine, and we swapped between scopes.
The night was great - average 21.96 SQM (her meter) over half a dozen samples after the moon set. Very good transparency with some smoke down low, early clouds, good seeing. Very light wind, 70F degrees decreasing to 63F by 1AM. 50% cloud cover early, mostly gone by 1AM. No light domes visible in any direction, but the night was quite “moony” especially due to the cloudy sky, so we focused our comparison toward the northeast when we weren’t looking at the moon.
Our first impressions of the other’s scope were the same - “nice piece of kit”, “looks just like mine”, etc. The TEC felt noticeably lighter, if a bit longer. The SVX feels subjectively more “solid” but I really liked the weight advantage of the TEC. Only a couple of pounds, probably, but noticeably easier to uncase, lift and mount, not that the SVX is exactly difficult. The rings were similar, with the TEC having a sort of latch mechanism vs the SVX hand knobs. She liked mine better, I thought they were about the same.
On closer inspection both scopes were extremely well-finished with flat white tubes and consistent anodizing. I liked the focuser end of the TEC better than my SVX, which looks a bit steampunk with its exposed adapter/reducer thread. The focusers were both FTs, but I thought the diagonal attachment collet on the TEC was better than the triple screws in my SVX. I like the objective cover better on my SVX; it’s a simple “hat” vs the TEC’s insert, which, while very well-engineered and tight-fitting, seemed a bit fiddly to me. I felt like I had to be very careful replacing the cover on the TEC, not so much on the SVX. My friend agreed. The SVX dew shield felt more secure and substantial.
So far, it’s sixes - we both preferred the SVX’s “business end” and the TEC’s focuser end. Overall quality was outstanding and basically indistinguishable. Off to the observing races…..
The moon. We took turns on each other’s scopes, unfiltered. I started with the Delite 7, she the Delite 3. The views were nearly identical in the 7, both being beautifully sharp, color free and with absolutely outstanding contrast. I thought the TEC was just a little bit warmer, the SVX whiter and more clinical, for lack of a better term. The 3 showed the same, though the TEC seemed a little less warm than it did with the 7. I was looking at a well-defined demarcation of sunlight at the very tip of a ridge near the terminator, and it was the best view of the moon I’d ever seen, in both scopes. Simply spectacular. No objective difference whatsoever, no pun intended, we both agreed. I doubt I would have noticed the warmth of the TEC’s view had they not been 10 feet from one another.
For grins and context, we tried the N31T5. Sharp as a tack in both, the sky was black, no color, fields were both basically flat to the edge. Again, no preference.
Our final moon views were with a 9mm Optimus. There’s nothing quite like seeing the entire disk of the moon at ~100x. The TEC’s warmth was evident. The SVX, maybe because of the lack of warmth, looked a little sharper.
Moon champ - a tossup.
We moved on to Albireo using the Delite 4MM. This showed a bit of a difference, with the SVX being slightly, but noticeably, brighter. The sharpness, color and contrast was the same in both scopes. Using the 2X Barlow, the SVX brightness advantage was less pronounced. Both scopes showed a nearly perfect image at 450X, give or take. Inky black sky with a blue/white and yellow double. Some nudging to keep up, which, as an aside, both mounts handled beautifully.
Winner - SVX by a nose due to perceived brightness.
Good time for an amateur star test using nearby Anser and the Delite 4. Simply put, not any difference that I could detect, with seeing probably 9/10. She thought the same. We weren’t that scientific about it, basically just defocusing in and out until the disk filled roughly 20% of the field. Both looked pretty textbook, no aberrations. She thought the TEC showed a barely perceptible darkening presenting as a thin outer diffraction ring, but I couldn’t see it. Both snapped through the on-focus position in the same manner.
Winner - tossup. I think.
Off to M13. Of the handful of objects we observed, M13 showed the greatest difference between the scopes, to me anyway. We tried the Optimus 9 and the Delite 7 & 4. The 9 obviously showed more context due to the wider AFOV but while the SVX again was a bit brighter, the TEC made M13 look, I dunno …. somehow better. I can’t even explain what that means, other than it was more pleasing to my eye. My friend couldn’t see any difference aside from the aforementioned “clinical” SVX view. Maybe that was the answer; I may prefer a warmer view of globulars. Switching to the 7 did nothing to dissuade me - TEC still looked “better” even while filling more of the field. Both scopes hinted at core resolution through the 4, very nice.
M92 was nearby, and impressions were the same as with M13, though there wasn’t quite as much difference between the scopes.
Winner - TEC by a head.
M57 was next. I hate that #@%! I think the roots of my anti-Ring pathology dates back to when I used to try (and mostly fail) to find it by star hopping in a narrow, F10 SCT. It did, however, look very nice, sharp and identical in both scopes through the Delite 3. I tried the Barlow with the 3, probably just out of Ring spite, and it flew through the field so fast that I became all p!$sed off at it again. Just like old times. I’ll admit, the little ba$!#rd looked great while doing so.
Winner - nobody wins with M57.
On to Caldwell 14. It is a sight to behold through the 9. Interestingly, the TEC showed FZ Persei as slightly redder, closer to the view through our 10” LX50. The SVX showed more orange. Again, it was a very slight difference, and my friend’s comment was “eh, maybe”. So “eh, maybe” it shall be. I chalk it up to the “clinical” thing with the SVX. Both were equally sharp with equal contrast. Thinking about it, the SVX reminds me a bit of an AP I looked through last summer, so color-free it looks like an expertly taken black-and-white photo.
Winner - TEC by a whisker due to the color of FZ Persei.
The last DSO we compared was M31 with the 31T5 after the moon set and well, wow. I love looking at that object through that EP, and it looked every bit as spectacular in the TEC. However, I have to say that unlike M13, I slightly preferred the SVX view this time, but only slightly so. It felt “fuller” to me. Her response was “oh yeah, it looks a little better.” Not enough to matter, really, just … a bit different.
Winner - SVX by a nose. Doesn’t make a lot of sense, but we both saw it.
We looked at Saturn once the moon set and it was higher in the sky. Unlike the rest of our targets, I could detect zero difference. We used the 7, 4 and 3 Delites and Barlowed the 4. Both scopes showed the planet, surface banding, 5 little twinkling moons, the rings and the gap perfectly. I have to say that though my brain knows I can see “more” of Saturn through my 10” SCT I much prefer the refractor view, even at 55% of the aperture. Simply stunning.
Winner - none.
The finale was an N31T5 sweep of the area between Scorpius and Sagittarius. Frankly it’s such a rich star field that it’s probably impossible to detect any difference between the scopes, and neither of us did. You get so wrapped up in the diamonds, and the velvet, and the occasional little ghostly nebulous wisp that any scientific purpose flies out the window. It was a fitting end to the evening.
Winner - none.
So, the payoff - which is better? Neither is perfect, and both are spectacular. The views are equally impressive. Had I not used them almost simultaneously I doubt I could tell the difference. Side by side, I preferred the SVX on some things and the TEC on others. I have to say that it’s quite possible the differences I observed were due to changes in seeing, eye position, clouds, dusty optics, the High West Double Rye, or a handful of other things. Maybe real, maybe not. They were very, very close.
The TEC, being somewhat lighter, has an ergonomic advantage and better finishing on the focuser end. The SVX has a simpler objective cover and a more robust dew shield. Basically they’re equals in nearly every sense, especially in the all-important viewing category.
I came away thinking I would have been perfectly happy with the TEC had the SVX not been available. My friend thought the converse was true. If they were sitting next to one another and some generous soul said “pick one” I’d probably pick the TEC for its handling advantage and slightly warmer views. But, and it’s a big but, if that person added “and pay for it and wait for it” to their offer I’d have to ask is it worth several hundred bucks more (fully equipped), and is it worth waiting 18 months beyond the SVX? I don’t think it is, but your mileage may vary.
This kind of comparison is probably a little silly with two world-class scopes. Nothing credible that I have read or heard lead me to think there would be any meaningful difference. There was, maybe, a little bit of each of us coveting what we don’t have, but nothing serious. We both agreed that it’s nice to be able to eliminate any lingering doubt one might have about his or her choices. We certainly accomplished that, and had a great night of observing to boot.
Cheers.
