How much IR can foxes see ?

Flashlights, IR illuminators. Projects, reviews and queries. DIY 'stickies' here too.
Trackerman
Posts: 123
Joined: 30 Oct 2017, 19:22
Location: ireland

How much IR can foxes see ?

Postby Trackerman » 26 Nov 2017, 22:43

I've read mixed web reports about how much IR foxes can see.
Some say they can't see it , others say they can see 850nm .

Could it just be that the pills emit a mix of 850 and lower frequency also, and the fox is seeing these ?

What experience have folk had with foxes?

Last night I'm fairly sure one of my foxes was spooked by my T20 (850nm).

Tracker

User avatar
sunndog
ADMINISTRATOR
Posts: 6366
Joined: 10 Jun 2012, 17:51
Location: buxton, derbyshire

Re: How much IR can foxes see ?

Postby sunndog » 26 Nov 2017, 23:04

I'm convinced they can see the glow at source. I don't think they react as they would with a lamp on them but rather react to the movement of that red thing in the distance
oslon black drivers
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

Davesniper
Posts: 74
Joined: 18 Mar 2016, 00:38
Location: Middlewich

Re: How much IR can foxes see ?

Postby Davesniper » 27 Nov 2017, 10:12

From my own experience I have lost count how many foxes have spooked on me at 100yds or less,I use the NM800 it helps only putting it on first mode at close range ..some foxes brake all the rules and will show intrest in the glow and others will bugger off...200yds shots they feel safer ...but yes they can see the glow.

User avatar
cliveward
FORUM SPONSOR
Posts: 1067
Joined: 02 Mar 2012, 20:19
Location: Ashford, Kent
Contact:

Re: How much IR can foxes see ?

Postby cliveward » 27 Nov 2017, 10:32

This is an interesting one.

It's assumed foxes see like dogs so they are essentially colour blind and have quite poor eyesight in terms of resolution.

So a normal red light would be seen as a dull grey / brown fuzzy glow.

They shouldn't be able to see IR and neither should we, however...

Recent studies show that if enough 'invisible' photons hit the retina in quick enough succession then it will trigger the cell and it will be interpreted as lower wavelength light. That's why we see a red glow from higher power IR emitters.

This would be seen by a fox as again a very much duller grey / brown fuzzy glow than a red lamp.

I've had foxes run straight up the beam of a B672 on full chat into a call without any issue.

I personally think some foxes are more wary than others, so any noise, smell or movement will spook them.


Cheers





Clive

User avatar
sunndog
ADMINISTRATOR
Posts: 6366
Joined: 10 Jun 2012, 17:51
Location: buxton, derbyshire

Re: How much IR can foxes see ?

Postby sunndog » 27 Nov 2017, 12:31

cliveward wrote:It's assumed foxes see like dogs so they are essentially colour blind and have quite poor eyesight in terms of resolution


I'd take that with a pinch of salt too. My dog has seen a fox @150yrds+ at dusk. Fox was well downwind and sat watching us, well not for long it werent :lol:
I could just make it out with the naked eye. I'd say he knew it was a fox too cos he hates them and was growling and trying to get after it lol

As for i.r its deffo the movement and/or noise they are reacting to imo. I'v had them come in to a static flood light then shy at the rifle mounted i.r
oslon black drivers
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

warbucks
Posts: 789
Joined: 16 Sep 2013, 15:14
Location: Dewsbury

Re: How much IR can foxes see ?

Postby warbucks » 27 Nov 2017, 15:30

I've shot a little over 750 foxes in the last five years.
If a fox in walking away from you and you shine a red torch on it, it will usually turn round and look direct into the torch, if its been shot at or lamped several times before its likely to run off.
If a fox is walking away from you and you turn the 850nm ir on it wont turn round it will carry on its business, if its partially facing you it will see the red glow (not the beam), depending on if its been shot at before it will spook, ignore or some time sit and watch.

couple of years ago i missed the same fox twice, every time i then went after this fox it would see the red glow and off, foxes like us do make mistakes, i waited for this fox from a different direction, when it came it was looking for the red glow where it was used to seeing it, this gave me the few seconds that i needed to get a successful shot off.----------i've also seen them spook with the red glow then 15 seconds later forget about it while still within the range of the centre fire rifle.

Any spooked fox that has stayed on that land, i have eventually shot it, some how ever do move on.

A lot of the times when we think that its the i/r that's spooked it we have made a mistake before using the i/r, pulling up in a vehicle, operating the bolt while the fox is listening, made some noise, ect, then when the i/r goes on its the last straw for an educated fox.

Dave (warbucks)

Trackerman
Posts: 123
Joined: 30 Oct 2017, 19:22
Location: ireland

Re: How much IR can foxes see ?

Postby Trackerman » 27 Nov 2017, 19:43

Thanks guys,
Good to hear what you think, I've only started shooting fox this year and only recently started NV. Before that I was using ordinary red light which seemed to work on my permission, for a while... but the last few nights have shown me that the remaining foxes know the red light is danger.
I'm using 850nm NV and can follow charlie walking about the field but he won't come into the call, he looks at it but then walks away.
Just as an experiment I've order a 940nm pill for my other torch, so i may be able to test the difference.

I was also thinking that the 850nm we can see (the dull glow) is simply because the source isn't pure 850nm, it's probably 'mainly' 850nm but also contains an element of visible light. A bit like a bell curve if you know what I mean.

has anyone tried a high pass filter to cut out light below 800nm ?

Trackerman

phoenix
BRUCE ALMIGHTY
Posts: 4571
Joined: 09 May 2012, 14:40
Location: Aberdeen

Re: How much IR can foxes see ?

Postby phoenix » 27 Nov 2017, 19:57

Hi pass filters don't generally have a sharp enough cut off to get rid of the light below 850nm without losing a fair bit of the light around 850nm
Perspex Black 962 is the most commonly used IR filter and you can see from the attached graph that it's not a particularly sharp cut off around the wavelengths we are interested in
https://www.ebay.com/itm/INFRA-RED-962- ... 1275392787

Cheers

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

User avatar
rodp
A bad influence
Posts: 4085
Joined: 09 Mar 2012, 22:49
Location: The Black Country

Re: How much IR can foxes see ?

Postby rodp » 28 Nov 2017, 16:52

Personally, I'm convinced a fox can tell the difference between an electronic call and a natural distress call. He probably doesn't realise it's artificial but does know "it's not right", after a couple of near misses or his mates going missing in action he then equates this with danger.
Thought this for a long time, after all, their hearing is far more sesetive than ours.

Edit to say it would be very interesting to compare a natural call (not recorded) against an electronic call on an analyser to see if there's any "stray" or blurred frequencies added to the electronic one.
Last edited by rodp on 28 Nov 2017, 16:58, edited 1 time in total.
"Land Rover, the worlds best 4x4 by far"

"Argo, a great 8x8"

Trackerman
Posts: 123
Joined: 30 Oct 2017, 19:22
Location: ireland

Re: How much IR can foxes see ?

Postby Trackerman » 28 Nov 2017, 16:54

Cheers Bruce, was worth asking I guess.


Return to “Illumination”

Who is online

Users browsing this forum: No registered users and 6 guests