Pard NV007 POI shift

[ferreter10]

I'm after some help from someone more intelligent than me!! 

I've been using my Pard nv007 on a combination of 3 scopes. All rifles are spot on without the pard fitted and in normal daylight, with the Pard fitted, everything works as it should.

The headache arrives when I switch the Pard over to night mode and use IR illumination. As soon as I do this, my POI shifts a long way on all scopes. The air rifle is least affected, moving POI about an inch high and right. The other two (.17hmr and .220 swift are affected much more. (A foot or more at 100 yards both up and left) Now, the only thing I change on the scope is the paralax between day and night as because of IR wavelengths differing from normal light, the Paralax on the scope has to be set alot closer to get a clear image. (Focus on Pard always set to focus on crosshair.)

 

Why is the POI changing!!! Is a mounting issue combined with IR illumination causing paralax error? I've tried re-mounting to no avail.

Any help appreciated! 

Jamie

[Ultrastu]

If the scope are ao adjustable for the parrellax  than that is most likely your issue .when you rotate your front lens your effectively  looking through a different  part of it for your cross hairs .

Try adjusting it as much as you do with the nv on during the day and you may see the same zero shift .

This often happens if your scope is not optically centred when its zeroed .ie if you have to dial in either a lot of elevation or wind age to get on target .a different set of mounts can help or adjustable  mounts to keep the scope optically zeroed when actually  zeroed. 

Or use a scope with side parrellax adjustment (though this can also effect it somewhat if your windage adjustment etc is great )

also the better the scope (quality brands etc ) the less this issue will occur  

[ferreter10]

Thanks for your input 2 of the scopes are side paralax, the other front ring. The Nikon Monarch is a brilliant scope and made to very high standards, and the error still occurs on this scope (front AO) ? Optisan obviously less so well made but still decent quality and this is one of the two side paralax adjustable scopes. 

In your opinion then, it not to do with a non centered mount from Pard to scope?

[Ultrastu]

It very much could be .

Parrelax error is an error in not lining the eye (or in this case the nv unit) up behind the centre of the scope exactly or more over the centre of the optical axis .

I'd try shooting during the day and confirming  zero at a set range then altering your px  either side or ao as far as you can both ways while still being able to get a clear enough sight picture to shoot well.

Try and replicate the error you find with nv .on during the day .

If that's not possible then look to the nv alignment  . 

[ferreter10]

Thanks ill try that!