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Posted: 12/7/2012 8:09:14 PM EDT
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I have an old 2nd Gen BE Meyers Night Invader and it takes a standard SLR lens up front. If I changed it out to a larger objective would I get any better performance?
The reason I ask is BE Meyers told me I had the same tube as a PVS-4 and the objectives on those are huge. |
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it should be a c-mount lens, not a standard slr lens. c-mount are for things like security cameras, and are much cheaper for suitable fixed fast lenses. for the most part, going to a larger lens will just increase your magnification. 25mm - 1x, 50mm - 2x, 75mm - 3x. I've seen accessory sets for these pop up on auction sites from time to time, its a suitcase full of lenses and adapters.
the pvs4 has a large objective lens but it is also a really high quality lens, that level of quality in a c-mount will cost as much as or more than a surplus pvs4, if that quality level even exists. Posted Via AR15.Com Mobile |
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Quoted:
There are two ways you can make a lens larger one is focal length which gives you more magnification the other is diameter which collects more light and gives you more system gain. The lower the f/stop the more light that is collected. The f/stop is a simple measurement, you take the focal length of the objective lens system and divide it by the usable glass diameter of the first lens in the objective lens system.
I have an old 2nd Gen BE Meyers Night Invader and it takes a standard SLR lens up front. If I changed it out to a larger objective would I get any better performance? The reason I ask is BE Meyers told me I had the same tube as a PVS-4 and the objectives on those are huge. Note, there is a number that is more accurate than the f/ but much harder to obtain, it takes into account the losses inside the lens system and is not normally published, it is the t/stop number. Edit: Be careful the lower the f/stop the harder it is to engineer a lens with low distortion. |
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