Increase magnification on night vision monocular

Can anyone shed any light on increasing magnification on a night vision device. i have just read a scientific paper on surveying birds at night on large fields. The surveyors used a gen 1 intensifier with a 400mm camera lens with illumination using a 1milllion candle power spot light with a IR filter. Has anyone here tried this kind of setup? They managed to identify different types of plovers at 400m

Sounds absurd. You can't identify between similar birds at distances a fraction that far without magnification on a gen one, and magnification reduces resolution. Maybe you can identify between a bird and a dog, but different similar birds is asking too much. I'd like to know where you read that.

The paper is:

Diurnal studies do not predict nocturnal habitat choice and selection of european golden plover and northern lapwings. Gillings et al.


Published in Auk 122(4): 1249-1260, 2005


It was a 300mm camera lens not 400mm as I first said, so magnification would be 6x plus what ever the image intensifier was (maybe 2x) giving around 12x mag overall. To me this seems feasable, I presume they used the the camera lens in a similar manner to a digiscoping setup (I presume you might not be familiar with the digiscoping concept?). Basically the camera lens acts as a light gathering source, this is much more than an objective on a normal night vision scope. The 100mm canon 300mm f2.8 lens has a 100mm objective lens capable of gathering a huge amount of light c. 4x that of a 42mm objective lens. The image intensifer then sits behind the camera lens. Anyway I will have a go and let you know.