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Yes, correct, you can't swap out the tubes with standard 18mm, on the other hand if you were swapping out tubes you either have a lot of money or you'd be in the military, in which case the Service would pay for the tubes and you wouldn't care as long as they worked well.
This is a great question and it touches upon many aspects. First, think about the 16mm market and all of the NODS that have them. Pretty much a mental blank right? The entire US market revolves around 18mm tubes and one of the reasons is that 16mm tubes are hard to make. The yields were historically low and for every tube you make you have to throw 8 or 9 away, however Photonis perfected the manufacture of 16mm tubes, which is great, except that there was no market for 16mm tubes in the US. Meaning, what housing could they go into? When you get your hands on one you'll be amazed at how small they are and what a difference it makes in housing design. Form follows function, so while the military has been pushing lighter and smaller, you could only go so far with a housing using an 18mm tube. So, the reason why we made a hybrid 18 is to rethink the way the tubes were made and since everyone understands 18mm tubes the transition from a full size 18mm to a slimmer one was an easier mental leap than an 18mm to a 16mm in a quad. In other words, we can make the PD-PRO-Q even smaller with 16mm tubes and if we had done that (back when we first started) it may have been a technical marvel, but perhaps a marketing disaster.
The 16mm systems and Hybrid 18mm systems will only be sold with our highest quality 4G tubes. "Commercial" tubes are tubes that don't pass inspection for military grade, or have flaws which caused them to not be able to obtain a 4G rating. Most of these flaws are usually black spots in critical zones that don't affect normal civilian use. They still work great, but are best suited for non tactical purposes. I have a Photonis Vyper Mono with an ECHO tube, and I use my Mono for hiking, stargazing and the occasional pig hunt. The PD-PRO series with their 4G tubes are available to any US citizen. The systems do fall under ITAR and cannot be exported or taken outside of the USA without an export license. So to make sure I explained that OK, our 16mm and Hybrid 18mm tubes are provided as 4G tubes only, and the tubes and their housings are available to any US citizen. We also make and provide PVS-14s with standard 18mm tubes and those tubes are available in 4G, ECHO, XD-4 and XR5 grades and these tubes and systems are also available to any US citizen under the same ITAR regulations.
We do not have INTENS tubes on the US side and Photonis no longer uses that name. The closest tube to those older ones would probably be the ECHO+ and maybe in a few cases a 4G. If a distributor has an INTENS branded tube it's still a solid performer and you won't go wrong with it.
It doesn't have to be specified and in many cases when you look at spec sheets - not just ours - it won't be. My reply was making the point that we need to change the way we have it listed now.
On the PD-PRO-Q there are two ways to power them. On the original design they were powered on/off with a magnetic switch. Lower the NODS and they turn on, raise them and they turn off. Well, some people liked that and some didn't. So, on the PD-PRO-Q there are two choices. You can get them with a manual switch or magnetic switch that powers them on and off. More than likely, we'll go with the manual switch vice magnetic for the US market. By the way, the PD stands for Photonis Defense; the PRO for Professional, and the Q is the Navy designation for "special mission."
Fantastic! By the way, I recommend you pick up a 1064 illuminator/laser. One test that was an eye opener for team members is when we asked them to bring their NODS to compare them with a PD-PRO product. We asked them to turn on their NODS and shine the 1064 laser at their feet. We asked if they could see it. All of them could see it using their NODS. We then asked them to move the laser spot out to the horizon until they couldn't see it. The average distance was perhaps 75 feet when they lost the dot. Then we had them do the same with a PD-PRO product, we only had a quarter of a mile before we ran out of terrain (we were by the ocean), but you could see the dot perfectly well on the distant treeline. It's just a visual indicator of what "out of band" or "extended range" or what we call "Hypersense" means. So to answer Will-1's question, yes it's a marketing name that speaks to the extended bandwidth of the 4G tube.
