I did not do the Gen. 3 board upgrade. I'll post some replies from Matt at Peak Beam and you guys can decide for yourselves what you want to believe. I'm only going by what he told me.
Your light before the upgrade was able to get a reading of 10.5 M CP. The other light got a reading of 10.2 M CP. The 10.5 M reading on the distorted reflector might have been a little artificially high for reasons that I talked about yesterday (focusable over relatively short ranges, but likely would not provide a well-focused, collimated beam over long ranges). I think these two higher readings also speak towards the quality of the lamp you have. In my opinion, an ushio lamp might increase the output slightly, maybe 1 or 2 million CP more, but you probably wouldn't really be able to notice that increase just looking at it.
It was nice talking to you earlier today and I am happy to be able to tell you that your light with a brand new reflector recorded an output of 17 Million CandlePower. While this is high, it is not that unusual for lights coming through production to reach this level or even higher.
Our range that we test all of our lights on is 83' from light to meter. I'd expect that you could quite possibly get a higher CP value if you measured over a slightly longer range. Attempting to measure CP at shorter ranges will definitely result in lower values. We set the spot limit (what limits forward travel) to reach the tightest spot at our range distance. There is really no reason to ever need to use spot at a closer distance other than testing. All of these limits can easily be over-ridden and reset using the controls on the searchlight.
You are correct that you cannot set spot limits on G2 boards, I forgot that you did not have a G3 light (but you do now have G3 output J). I have done studies on how CP readings of the maxabeam will be effected by taking measurements at shorter ranges for some of our customers that wish to test the output of their lights but only have, say 30' to work with. These readings would be much less because the searchlight is programmed not to be able to focus down that far on G3 lights.
At longer ranges you really should get a very similar reading. There are two things that would affect the longer range readings: 1) Atmospheric conditions (i.e. dust or moisture in the air that could diffract light) and 2) The physical difficulty of focusing the light to that distance and hitting the meter exactly. You will have to make sure the x and y focus is correct at a shorter range, which it should be already, although depending on how rough shipping was you might need to slightly adjust this. And you will have to make sure it is zoomed correctly so that you have a perfectly collimated beam (important that you are not actually alightly past spot since there is no spot limit on your G2 board).
So hypothetically your measurements should be exactly the same with the few caveats I noted above. There is no calculation for how CP changes over distance because it shouldn't change (CP accounts for distance) assuming you could hold everything else constant.
There is no scientific rationale to see a major drop-off in CP between measurements at 30m of 100m unless there is a lot of particulates/moisture in the air or the measurements are being taken incorrectly. The correct level of z-focus (spot to flood adjustment) will change for 30m vs. 100m. If this is not adjusted between the two measurements, one or the other will be inaccurate because the beam will either be over-focussed or under-focused depending on which measurement is performed first.
X and Y focus should remain the same for all distances once it is set correctly, but every distance will have its own perfect degree of z-focus that will maximize the amount of collimated light at that point. I suspect that anyone who sees a large drop-off between relatively close distances doesn't have the correct z-focus on their maxabeam or the inability to fully adjust the z-focus on a different type of light.
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