Does DIY nightvision affect accuracy?

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cadman777
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Joined: 25 Oct 2017, 15:40
Location: Florida

Re: Does DIY nightvision affect accuracy?

Post by cadman777 » 14 Dec 2017, 12:52

Thanx for your input somebloke.
I figured it had something to do with parallax.

My scope does NOThave an adjustable objective.

I read somewhere that you can remove the objective bell and screw the i.d. ring ompit to adjust for parallax. But they cautioned that some scopes will release the nitrogen if they aren't designed to adjust parallax like that at the factory. So I didn't try making that adjustment yet, b/c if the nitrogen releases, the scope will be rubbish. I have a Barska scope, BTW. Trying to get those geezers to respond is like trying to talk a judge into helping you when he works for your mafia opponent. Anyways ...

Any ideas about my scoope?

poppy mae
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Joined: 19 Aug 2012, 21:21
Location: Wirral Chesire

Re: Does DIY nightvision affect accuracy?

Post by poppy mae » 14 Dec 2017, 12:54

Buy a new one , with parallax , save a lot of hassle! Want one that focus down to 10yds.....

cadman777
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Joined: 25 Oct 2017, 15:40
Location: Florida

Re: Does DIY nightvision affect accuracy?

Post by cadman777 » 14 Dec 2017, 12:58

Hey poppy, thanx for the advice.
Which inexpensive scope would you recommend?

Meanwhile, I'm thinking of turning these components into a hand-held nv scope.
Just need to find a good quality 20x zoom lens that won't break the bank!

poppy mae
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Joined: 19 Aug 2012, 21:21
Location: Wirral Chesire

Re: Does DIY nightvision affect accuracy?

Post by poppy mae » 14 Dec 2017, 13:14

see what cabelas or bass pro have in the xmas sales , or whats local to you, need something with a/o ( on the front ) or side parallax really, but do make sure it focus down to 10yds or so , or you will have trouble ratting with it.....

phoenix
BRUCE ALMIGHTY
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Location: Aberdeen

Re: Does DIY nightvision affect accuracy?

Post by phoenix » 14 Dec 2017, 13:17

Re an inexpensive scope - have a look at the Bushnell rimfire optics 3-9x40 (p/n 633941)
It does have side focus but I can't find any info on how close it adjusts
$99 from Optics Planet.
Bushnell scopes have traditionally worked well with NV add-ons, so it should do the job

Cheers

Bruce
LAND ROVER - THE WORLD'S WORST 4X4 BY FAR

cadman777
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Joined: 25 Oct 2017, 15:40
Location: Florida

Re: Does DIY nightvision affect accuracy?

Post by cadman777 » 14 Dec 2017, 13:24

poppy/Bruce,
Thanx!
I'll look into it.
Cheers ...

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some bloke
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Re: Does DIY nightvision affect accuracy?

Post by some bloke » 14 Dec 2017, 14:36

cadman777 wrote:Thanx for your input somebloke.
I figured it had something to do with parallax.

My scope does NOThave an adjustable objective.

I read somewhere that you can remove the objective bell and screw the i.d. ring ompit to adjust for parallax. But they cautioned that some scopes will release the nitrogen if they aren't designed to adjust parallax like that at the factory. So I didn't try making that adjustment yet, b/c if the nitrogen releases, the scope will be rubbish. I have a Barska scope, BTW. Trying to get those geezers to respond is like trying to talk a judge into helping you when he works for your mafia opponent. Anyways ...

Any ideas about my scoope?
I've done exactly that with a fixed mag and focus WTC 4-40 for ratting - the first in this video. I have it in my head that Barska scopes are inexpensive so there's not a lot to lose by trying that at the sort of range you will be happy at on every outing.

https://www.youtube.com/watch?v=2w4SA4tvT0k&t=5s
Image

Trackerman
Posts: 134
Joined: 30 Oct 2017, 19:22
Location: ireland

Re: Does DIY nightvision affect accuracy?

Post by Trackerman » 17 Dec 2017, 12:30

This might help...
I too have a scope with NO parallax adjustment and it's a PITA.

But to compensate a little I have made two openings in my scope tube which allow me to adjust the ocular focus ring while the tube is in place.

I then 3d printed a sleeve to cover the opening, this can be omitted if your not a wet weather shooter.

I did the same same for the camera lens, this makes it dead simple to fine tune the cross hairs focus.

Photo below...

Image

Image

cadman777
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Joined: 25 Oct 2017, 15:40
Location: Florida

Re: Does DIY nightvision affect accuracy?

Post by cadman777 » 17 Dec 2017, 17:08

Hi Tracker,
You won't believe it, but my 3D print design looks like yours, except I designed a different camera lens adjustment due to using a Sony E700.
Unfortunately, I didn't find any fix by adjusting the camera lens after initial focus adjustment outside of the scope mount.
Would you please list the steps you used to sight-in yours?
Maybe I'm not doing it 'right'?
Thanx ..

PS: How come I can't add any pics?

Trackerman
Posts: 134
Joined: 30 Oct 2017, 19:22
Location: ireland

Re: Does DIY nightvision affect accuracy?

Post by Trackerman » 17 Dec 2017, 22:07

HI Cadman, they say great minds think alike and fools seldom differ ! :angel:

Anyway my setup approach was like this.

I firstly found the 'camera to scope' distance by finding the distance which gave me a comfortable image of the 'viewing circle' with the 4 sides cut off (i.e. the image filled the LCD screen with just the corners in darkness) this was with a 16mm lens, this worked out to be 7.5cm (scope to camera board).

I then mounted the camera and first adjusted the camera lens for best cross hair focus.
Then adjust the scope for best image sharpness at a distant object, be sure to use a distant object (say 50 meters) and not something close.
Then re-adjust the camera for cross hair focus.
Repeat these last two steps if necessary.

This may help, put a dot in the middle of the lcd (measure it out properly) and adjust the camera angle so the cross hairs sit dead center of the screen.

If the scope goes out of focus when you zoom then this is a bad characteristic of the scope unfortunately.

I'm not sure this answers your question though, does it?
Your problems seems to be the camera is not looking dead straight at the projected image from the scope, but is looking at an angle somehow.
Alternatively your eye is not looking at the middle of the projected image, test this by moving the eye further from scope.. the image will reduce in size but you should end up with a very small viewing area.. this is close to dead center of the projected image.
If you place the eye too close to the scope you can create a viewing error, at least that my experience.

Tracker

PS, to add pics you need to upload the image to something like Photobucket and place a link in your post.

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