NV Add ons and zero shift

[cliveward]

Hi All,

As you know I love a good 'technical' discussion, as I believe it promotes knowledge.

Recent threads have reminded me of a theory I have. See if you can follow this...

My theory is that the point of impact should be different when you use a day scope during the day...and then use the same scope at night with an add on NV unit and very powerful IR laser illumination.

My reasoning for this theory is that IR light is refracted or bent less than visible light by lenses. I would assume that if the scope was optically centred then this would not be an issue, but if a lot of windage/elevation was needed to zero the scope then there would surely be some error?


Cheers





Clive

[Marky610]

Or is it because you dont sell add-on's and wont to put people off them?

You have a day/night at the flick of a button scope try it on that surely the effect will be the same? Or is the whole idea pants because as stated in the worlds most boring thread that a image intensifing tube amplifies all wavelengths of light not just ir?

[cliveward]

Or is it because you dont sell add-on's and wont to put people off them?

If I wasn't such a nice guy I could take considerable offence at that remark. I think you have made the very wrong assumption that I'm here on the BBS just to flog night scopes...far from it. I think you will actually be quite hard pressed to find that many members who have purchased 'anything' from me. The reason being is that I try my hardest to stick to the 'no advertising' rules. And as a result of that most people don't even know what business I'm involved with.

I'm certainly not trying to put people off add ons. It's not that we can't sell them or don't sell them. ;) ;) ;) I actually think in some circumstances they can be the best option.

The reason for this thread is to promote knowledge. I'm asking the question, because I don't know. There must be some error, but it may be it's so small that it simply isn't an issue. On the other hand there maybe some poor soul reading this who has got badly aligned mounts and the errector tube way off the axis of his day scope to compensate, wondering why his POI changes so much when he uses his add on. With this knowledge he could optically centre his scope by getting better mounts or adjustable ones and cure the problem.

You have a day/night at the flick of a button scope try it on that surely the effect will be the same? Or is the whole idea pants because as stated in the worlds most boring thread that a image intensifing tube amplifies all wavelengths of light not just ir?

Nope they don't work the same way...I won't offend you by boring you as to why. I also won't offend you further by boring you as to why the add on system uses mainly IR light, instead of the broader spectrum a dedicated scope uses.




Cheers





Clive

[niko]

got to say ,never had the zero shift useing mine ,thats with a mk3(gen1) and a d121 (gen2+)

[bennyblanco]

again i have not had any problems with my two gen1 systems and the d121 i now have, on the other hand i have never shot paper with the add on system.

i might have a play on the next dry night as it not far to my nearest shoot(24yds:D ), i will try the hmr at 70yds with and without the add-on and with laser and torch light.

i think there could be a problem if you mounted it inaccurately although i don't have any evidence of this, i focus the laser beam and mount the nvd so the beam is central rather than adjusting the laser to the centre. just my way of doing it but at least its pretty repeatable.


ben

[Baldie]

I can't see the original post, but from the replies, I can guess the content.

If there was a 'zero shift' the technology wouldn't work. The End. :rolleyes:

Take a look on any of the NV Forums where people can have any equipment they want. Either high end dedicated at x6 with Gen III or DEP tubes, or similar spec tubes inside monoculars fitted to the back of dayscopes.


I have said it a number of times, but I will put any of my rifles with Gen I add-on up against whatever tube, whatever mag you can use.

Another, silly, silly thread. :rolleyes: