Found this on another thread. Scratching my head now after putting a deposit on the trail xp50 after looking at the data showing it compared to the apex75. What is the wt1 75-3? Can't find these for sale..
phoenix wrote:
Agreed, system resolution is the best objective measure of thermal riflescope or spotter detection capability
It's easy to calculate:
Simply divide the pixel pitch in microns by the focal length of the objective lens in mm
The answer you get is in millirads (mrad) the same as the turret adjustments on a lot of tactical scopes.
The lower the number, the higher the resolution (i.e the smaller the object that can been seen)
A few examples
25 micron core with 50mm lens e.g. Pulsar Apex XD50 = 0.5mrad
25 micron core with 75mm lens e.g. Pulsar Apex XD75 = 0.33mrad
17 micron core with 50mm lens e.g. Pulsar Trail XP50/Pulsar XQ50/Pulsar Helion XQ50F, WT1-50-3 = 0.34mrad
17 micron core with 75mm lens e.g WT1-75-3,or WT1-75-6 = 0.22mrad
12 micron core with 60mm lens e.g. IR defense IR Hunter MkII = 0.20 mrad
So, virtually no difference between the old Apex XD75 and the new Trail/Helion Pulsars
and virtually no difference between the Ward 7-3/75-6 and the much vaunted IR Defense IR Hunter
A 12 micron sensor with a 75mm lens would be the dogs bo****ks
I was reading some research papers on thermal cores and it seem that the lower practical limit for pixel size will be somewhere between 5 and 10 microns - and probably closer to 10 than 5
phoenix wrote:
Agreed, system resolution is the best objective measure of thermal riflescope or spotter detection capability
It's easy to calculate:
Simply divide the pixel pitch in microns by the focal length of the objective lens in mm
The answer you get is in millirads (mrad) the same as the turret adjustments on a lot of tactical scopes.
The lower the number, the higher the resolution (i.e the smaller the object that can been seen)
A few examples
25 micron core with 50mm lens e.g. Pulsar Apex XD50 = 0.5mrad
25 micron core with 75mm lens e.g. Pulsar Apex XD75 = 0.33mrad
17 micron core with 50mm lens e.g. Pulsar Trail XP50/Pulsar XQ50/Pulsar Helion XQ50F, WT1-50-3 = 0.34mrad
17 micron core with 75mm lens e.g WT1-75-3,or WT1-75-6 = 0.22mrad
12 micron core with 60mm lens e.g. IR defense IR Hunter MkII = 0.20 mrad
So, virtually no difference between the old Apex XD75 and the new Trail/Helion Pulsars
and virtually no difference between the Ward 7-3/75-6 and the much vaunted IR Defense IR Hunter
A 12 micron sensor with a 75mm lens would be the dogs bo****ks
I was reading some research papers on thermal cores and it seem that the lower practical limit for pixel size will be somewhere between 5 and 10 microns - and probably closer to 10 than 5