Contax Carl Zeiss Triotar T* 5X loupe vs. NPC Pro 5.5X loupe

In my hunt for the best loupe on the market, I looked at all the top loupes in a side by side comparison: Jobo 4X, Jobo 8X (only 2/3rds frame, also released under the Pro-Optic and Mamiya Pro Cabin name), Peak 4X, Schneider 4X, Schneider 6X Aspherical, Canon 4X, Rodenstock 4x Aspherical, Rodenstock 6X Aspherical, and Contax 5x (which has Carl Zeiss glass, with his T* coating). All the loupes were good, and all of them would be a fine one to own. Without going into great detail about the loupes mentioned above (since I didn't view them for an extended period of time), I can say that the Contax 5X was my favorite, the Schneider 6X was a close second (didn't have quite as good edge sharpness as the Contax), and the Canon was my third favorite (not quite high enough power though). I had heard really great reviews of the NPC Pro 5.5X loupe, but no one in Portland or Eugene seems to carry it. Since it was the only top rated loupe I had not looked at, and out of the ones I had looked at the Contax was my favorite, I ordered the Contax ($179) and the NPC ($119) from B&H, with the intention of keeping the one I liked better, and returning the other one.

First Impression (Build Quality)

Operation & Ergonomics

Actual focusing is done easier on the NPC than the Zeiss. The Zeiss loupe is suppose to be adjustable between -4 and +.5 diopter, but for my eyes the lower 2/3rds of the scale all looks the same, while the upper 1/3rd is obviously blurry. This makes me uncomfortable with focusing it because it shouldn't be this way; I should be able to find a spot where the focus locks in, and movement of the focusing dial in either direction blurs the image. Maybe this is just something unique to my eye, I don't know, but I don't have this problem with the NPC. It doesn't snap right into focus like a lens on my camera does, but I definitely am able to find a spot where movement in either direction does slightly pull the image out of focus.

One thing that is disappointing with both pieces is that I am unable to focus to a sharp image without my contacts in. My vision isn't that bad, and without my contacts in I can bring the image in the view finder of my F5 into focus by setting the diopter dial at -1. As mentioned above, the Zeiss loupe is suppose to have diopter adjustment down to -4, so it doesn't really make sense that I can't get a sharp image. Definitely a bad thing because closing one eye for an extended period of time with my hard contacts in tends to irritate my eyes. Soft contact users probably won't have this problem.

One of the main reasons I wanted to try out the NPC loupe was its eye relief (opening of the eye hole). The Zeiss' eye relief is a mere 20mm, whereas the NPC's is 28.575mm (it's spec'd at 1 1/8th inches). I was worried about eye fatigue with the Zeiss. When looking through the loupes though, the difference isn't even noticed. What is noticed on both loupes is a little halo around the outside edge of the frame. I'm not just talking about seeing the edge of the loupe, but there is a semi-transparent halo at the edge. This is more noticeable with the NPC loupe, and it gets to the point where it's slightly distracting while viewing your slides. To make matters worse, the NPC just barely covers the full frame of a 35mm slide. This means that the white halo is visible on the corners of the frame. Due to this, I had to move my eye around just a bit to view the whole slide. It isn't too big of a deal, but not ideal. This also means that you really have to place the loupe exactly over the center of the slide in order to have a chance of seeing the full frame. The Zeiss loupe has a bit of room to spare, so getting the loupe exactly center isn't as crucial. Also, that aforementioned halo doesn't get in the way at all with the Zeiss glass.

...and The Optics

The Zeiss loupe seems to have a bit more of the "head in a vise" syndrome than the NPC; you really have to keep your eye steady to keep the image sharp. The NPC gives you very slightly more room to move around.

The center of both of these loupes is perfectly sharp. As all loupes do though, both of these suffer from some image degradation towards the edge of the frame. This degradation is only on the outer 10% or so of the frame though, so for viewing 35mm slides it shouldn't a problem, because the slide mount is what covers that outer edge. Sure, the corners probably won't be as sharp though. The way I determined the quality of the edge sharpness was by looking at a 6x9 transparency. At the extreme edge of the frame, the NPC is slightly more blurry than the Zeiss; however, the Zeiss starts getting blurry farther towards the center than the NPC, though probably by just 3mm or so. Again, these edge sharpness problems generally aren't going to be a problem while viewing 35mm slides.

The Verdict

If cost is the absolute deciding factor for you, the NPC may be the way to go... but the way I look at it is: If you're going to spend $120 on a loupe, why not $180? It's really not that much more. I do think that the Contax is probably better designed though, and easier to view your slides with. In my opinion, these are definitely two of the top loupes on the market, if not THE top two. The only loupe I haven't checked out that I would have liked to is the new Leica loupe. As I mentioned above, the Schneider 6X Aspherical and the Canon 4X are also great loupes... combined with the two reviewed here, these are definitely the top four loupes on the market (in my opinion, obviously). A loupe is a very personal decision though; what one person may find very comfortable to use another may not like very much. In my opinion though, the Contax - Carl Zeiss Triotar T* "Lupe" 5X is the best full frame 35mm loupe on the market.