Choose the right IR for the job.

Flashlights, IR illuminators. Projects, reviews and queries. DIY 'stickies' here too.
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cliveward
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Choose the right IR for the job.

Post by cliveward » 03 Apr 2018, 12:01

Hi All,

I've noticed on other social media there is a bit of a misinformation on infra red illuminators.

Essentially Sunnranger types being suggested as the perfect IR for all scenarios. :roll:

One of these scenarios is suggesting it for wide angle, low mag devices like the new N355 with it's 3.5x native mag, with the advice to 'just widen the beam to suit the field of view'. :shock:

One issue is that the lens can't physically do this so that leads to white out due to uneven exposure on the camera, so you have to fanny about with the power levels. The other issue is the multi element lens on the Sunnranger is very inefficient but it will focus very tightly.

In my power testing a sunnranger focused as tight as it will go, will give about the same power density as a quite considerably wider beamed 50mm aspheric, again focussed as tight as it will go. The amount of IR hitting the target is pretty much identical, but the aspheric has a wider beam to work with and subsequently a lot more total output.

Now if you are having to widen the beam of your IR (to better fill the field of view of your NV device), power density drops off rather quickly.

I re-tested. This time setting the Sunnranger to the same diameter beam as the 50mm aspheric. It was no huge surprise that the 50mm aspheric now had twice the power density of the Sunnranger and would have 50% more range in the field.

Sunnrangers are a great compromise of size and weight for a tight beam diameter, but for applications under 10x magnification, then 38mm and 50mm aspherics are still much more efficient (and lighter).


Cheers





Clive

blueroll
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Re: Choose the right IR for the job.

Post by blueroll » 03 Apr 2018, 17:15

Clive.
That is great info, many thanks.
I did wonder if the multi lens of the Sunranger would be a drawback, but it is very handy with it`s rubberised lens to go from flood to spot quickly (for a retreating Charlie) and without a floppy head. Can you suggest an alternative ?

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some bloke
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Re: Choose the right IR for the job.

Post by some bloke » 03 Apr 2018, 19:12

I think quite a few people buy it because it sounds cool - and someone on facebook said its brilliant so they must be right. :angel:

The main thing I found with my red one was the beam edge seemed cleaner, possibly because of less spill and dare I say more round?

I gave it to my brother because my other T20 based red torch with a Neewer 2 x telethingy lens is much brighter and lighter, and he aint getting that. :D
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Re: Choose the right IR for the job.

Post by blueroll » 04 Apr 2018, 15:06

blueroll wrote:Clive.
That is great info, many thanks.
I did wonder if the multi lens of the Sunranger would be a drawback, but it is very handy with it`s rubberised lens to go from flood to spot quickly (for a retreating Charlie) and without a floppy head. Can you suggest an alternative ?
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Re: Choose the right IR for the job.

Post by reindeer » 05 Apr 2018, 08:09

When the 4715AS led became available, I installed one in my 4715S Sunnranger. I was quite disappointed with the results; as much as the old T20 S benefited from the 3x42 lens, as little improvement, if any, was noticable with the AS pill, probably because of the absorbtion of light by the thick, mutiple lens system in the Yukon 3x42 lens.
No fence is too tall.......

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Re: Choose the right IR for the job.

Post by blueroll » 05 Apr 2018, 10:51

blueroll wrote:
blueroll wrote:Clive.
That is great info, many thanks.
I did wonder if the multi lens of the Sunranger would be a drawback, but it is very handy with it`s rubberised lens to go from flood to spot quickly (for a retreating Charlie) and without a floppy head. Can you suggest an alternative ?
????????????????????
Anybody ???????????????????

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sunndog
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Re: Choose the right IR for the job.

Post by sunndog » 05 Apr 2018, 12:39

Standard t20 with AS pill any good to ya?
oslon black drivers
http://nightvisionforumuk.com/viewtopic.php?f=35&t=2333

when asking for advice, please include what n.v device and/or illumination you already have (if any) and what rifles you intend to use them on...cheers

blueroll
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Re: Choose the right IR for the job.

Post by blueroll » 05 Apr 2018, 21:21

sunndog wrote:Standard t20 with AS pill any good to ya?
The illumination is not the problem as I also have BS502. I am referring to the ability with the Sunranger to quickly go from flood to spot with Yukon lens, with its rubber grip (good for a thick gloved hand that has been carrying the sticks on cold winter night) and without the floppy head.

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sunndog
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Re: Choose the right IR for the job.

Post by sunndog » 05 Apr 2018, 21:26

Yeah i think thats the sorta thing clive was reffering to mate. You could try a 24mm yukon lens....cant remember what the flood was like on it though
oslon black drivers
http://nightvisionforumuk.com/viewtopic.php?f=35&t=2333

when asking for advice, please include what n.v device and/or illumination you already have (if any) and what rifles you intend to use them on...cheers

blueroll
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Joined: 28 Nov 2014, 20:34
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Re: Choose the right IR for the job.

Post by blueroll » 06 Apr 2018, 09:44

sunndog wrote:Yeah i think thats the sorta thing clive was reffering to mate. You could try a 24mm yukon lens....cant remember what the flood was like on it though
Okay thanks.

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