Night vision equipment for mortals (3 Viewers)

[jurek]

Looking for advice on night vision equipment which is practical to use in the field and still within a price range of a normal birder.

So far, I did not bother with night vision equipment, because I thought that it is
- too expensive
- field of view is very small compared to binoculars, so finding birds or mammals in the field is pain,
- many birds and mammals are invisible because they don't emit more heat than their enviroment.

However, apparently some people recently use night vision equipment which is within price range of a good bins or scope, and practically useful.

So I am looking for practical advice of those who actualy used a paticular model for night mammals and birds.

 

[Mono]

many birds and mammals are invisible because they don't emit more heat than their environment.

Most consumer night vision does not use thermal (heat) infra red. It either uses image intensifiers to boost the visible light levels, so won't work in total darkness but will work in moonlight or even starlight. Or it uses so called near-infrared, shining a torch, or a floodlight, of light that is invisible to us and then using a camera sensitive to that light to see. Some devices will use a combination of the two.

With the advent of cheap LEDs and digital cameras the prices the prices of systems have come down but the cheaper ones still suffer from limited field of view and short range. People also overestimate what they are going to get when they see pictures on TV from nature documentaries with state of the art systems.

 

[PYRTLE]

Like everything, it depends on what your budget is and how often your going to use it. A basic model is usually low magnification, monocular type with basic infra red courtesy of a light.
Yukon and Bushnell have many years of experience with these systems, around €300. A very usable system is the Yukon 7 x 50 monocular.

 

[Hauksen]

Hi Jurek,

Looking for advice on night vision equipment which is practical to use in the field and still within a price range of a normal birder.

I guess you would need to specify what you mean to use it for

It's also worth noting that many normal birders have invested considerable sums into alpha scopes, so you might want to be more specific about price tag.

With regard to technology, I believe the options are:

- Light amplification
- Near IR monochrome vision
- Thermal imaging

Light amplification relies on the presence of faint light sources. The advantage is that it might even give you a colour picture, if the faint light is white.

Near IR as currently implemented provides monochrome vision. It also relies on illumination, but it can be provided by pure IR emitters so that wildlife won't be able to detect it. I have a trailcam to monitor my bird feeder that has an IR mode too (not very useful for birding), but I tried it out and in combination with the LED IR flash, it provides clear monochrome photographs in a dark environment.

Thermal imaging does not need any illumination and is capable of detecting wildlife based on body temperature alone. The output usually uses a monchrome or synthetic colour picture that enables you to pick out heat sources visually. To actually identify these, you'll probably need a secondary vision system. Some devices apparently combine a conventional camera picture with the thermal image to make interpretation easier, but that might be a feature of higher-priced systems.

I have no experience with thermal imaging, but I looked at the available sets just before christmas before deciding I didn't actually need another expensive toy at the moment

The device I was looking at was the Seek Thermal Reveal XR, which is the higher resolution, long focal-length variant of that brand. (It was offered for around 400 EUR at a pre-christmas sale.) I figured that maybe their next model might be good enough for birding.

Forum member Vollmeise bought a much more professional (and 10 times more expensive) thermal imager in 2017 and posted a short report here on this board. Maybe we should ask him for a long-term experience follow-up on this ...

https://www.birdforum.net/showthread.php?t=354851

It seems the Pulsar Helion XP has a resolution of 640 x 480 pixels, which is equivalent to 0.3 Megapixels black-and-white.

The Seek Thermal Reveal XR offers a resolution of just 206 x 156 pixels, which is just 10% of that.

(So it seems thermal imager price scales linearly with number of pixels ;-)

Regards,

Henning

 

[Peter Audrain]

I'm considering getting a pair of 56mm binoculars, to be my 'night vision' equipment for owling. I read about thermal imaging, and it seems as if it is very much still awaiting its cost-to-quality revolution. And I found the world of regular night vision equipment very confusing, as well as populated with manufacturers I knew little about and websites offering click-to-buy links. I was also turned off by the high cost of 'Generation 2' or higher binoculars.

But I'd love to see a detailed review, from a birdwatcher's perspective, of a broad selection of current night vision binoculars (or monoculars—those posts by Vollmeise on the too-expensive Pulsar Helion, which I hadn't seen before, are fascinating). I'd guess other birders have gone down the same rabbit hole, eventually emerging without clear conclusions, and would welcome such an overview, too.

 

[jurek]

OK, since people seem confused what to be understood as "night vision equipment usable for wildlife watching with accessible price".

Pulsar Helion XP reviewed by Vollmeise is usable for wildlife watching (image resolution, field of view and size make it practical for watching wildlife). I find it too expensive personally, but since at least one birder bought it, lets treat it as a benchmark. For now this is the cheapest thermal vision equipment (from the sample size of one) which optical performance serves the purpose.

I would be interested in models cheaper up to about the same price, of any kind of night vision, their price, performance and pros/cons for actually watching wildlife in the field.

 

[Peter Audrain]

Me too.

(And having just clicked around the web on this topic, I might also wonder if anyone has used or formed well-informed opinions about the FLIR Scout TK. It seems to be the cheapest option, at $500, in the overall category of the Pulsar Helion—or at least to have been the cheapest option pretty recently.)

P.S. I think 'Yukon' is now 'Pulsar'—they changed their name.

 

[Hauksen]

Hi Peter,

(And having just clicked around the web on this topic, I might also wonder if anyone has used or formed well-informed opinions about the FLIR Scout TK. It seems to be the cheapest option, at $500, in the overall category of the Pulsar Helion—or at least to have been the cheapest option pretty recently.)

While its technical data lists a 640 x 480 pixel display, the statement on the sensors mentions "160 x 120". I'm not sure what that means, but it might well be they are using interpolation to display a more natural image based on a low-resolution input.

Regards,

Henning

 

[Peter Audrain]

Yes—that may be what the sample images posted by the company suggest, too. The images nonetheless look all right, at least in theory, for locating birds you wouldn't otherwise see, like owls. If anyone else owns and has used devices in this family, perhaps we'll learn the extent to which theory and practice overlap.

 

[Hauksen]

Hi Peter,

The images nonetheless look all right, at least in theory, for locating birds you wouldn't otherwise see, like owls. If anyone else owns and has used devices in this family, perhaps we'll learn the extent to which theory and practice overlap.

The FLIR Scout TK manual features a distinction that might be of interest for the purpose of our discussion, too:

- Detection: "I see something"
- Recognition: "It's a four-legged animal"
- Identification: "I can tell it's a dog"

I haven't found any birder's reports, here are some statements from hunters:

- Can detect (recognize?) hares at 200 m
- Can't identify sows vs. deers at 200 m
- Can't detect the broad side of a deer at 120 m against a warm background (meadow in May)

The display seems to be bright enough to interfere with one's night vision, so the advice is to always use the non-dominant eye with the FLIR so the other eye retains night vision to pick up the detected target visually.

One hunter's review states that the Scout TK has a 1x magnification.

My own approach would be to correlate the 160 horizontal pixels and the 20 degree horizontal field of vision to conclude that the resolution is 8 pixels per degree. However, a sub-pixel-sized target might show up with an average temperature above ambient, so one probably can't directly correlate target size and range. I figure a hare at 200 m would be less than half a pixel in broad-side view.

The display update frequency is stated by the manual as "< 9 Hz", which I think might require very measured panning if you're looking for anything.

Regards,

Henning

 

[Hauksen]

Hi Peter,

I'm considering getting a pair of 56mm binoculars, to be my 'night vision' equipment for owling. I read about thermal imaging, and it seems as if it is very much still awaiting its cost-to-quality revolution. And I found the world of regular night vision equipment very confusing, as well as populated with manufacturers I knew little about and websites offering click-to-buy links. I was also turned off by the high cost of 'Generation 2' or higher binoculars.

I just happened to come across this low-cost do-it-yourself image intesifier/infrared illumunation system:

https://www.thingiverse.com/thing:3365043

I suppose it might be really good for locatin owls that are looking at you from the dark, as I'd expect their eyes to give a good reflection. Less cooperative owls are probably not going to be so easily spotted, though! ;-)

Regards,

Henning

 

[Peter Audrain]

Hi Peter,
I just happened to come across this low-cost do-it-yourself image intesifier/infrared illumunation system

How fun is that! Something to think about this summer, for sure.

I've found a meadow with multiple Short-eared Owls hunting around, starting a little before sunset—they're partly diurnal—and sometimes expressing their unhappiness with the Northern Harriers still flying around from the day shift. So at least for the time being the urgency of my wish for full-on night vision is lessened.

At least, the *practical* side of my wish is lessened. The gear-loving side is still in love with the whole idea and wants a thermal spotter pronto!

 

[Farnboro John]

I use a Yukon scope regularly for mammalwatching - you can't really do that without some sort of aid at night, and white light causes most small mammals to flee while red light is sub-optimal for human eyes!

Monochrome viewing is fine for finding and watching stuff. Most nocturnal mammals will give you eyeshine due to their tapetum lucidum (reflective layer behind the sensors on the retina that enables them to derive twice the signal from any light) - humans don't, I've found from trying it on friends accompanying me. Owls also give eyeshine. You get eyeshine from the near-IR torches as well as from visible light.

Obviously this only works when they are looking at you but these are alert creatures either hunting or being hunted - they look around all the time and unless they are deliberately lurking from a predator or intent on detected prey they will not concentrate on one direction for long. Patience pays.

The Yukon is fine on its own (with built in near-IR torch) for activities up to e.g. badger watching where the distance is no more than about 30 metres. Beyond that I often use a more powerful IR torch (actually its a gunlamp) with a very narrow beam - I'm fairly sure its a Fenix - in combination with the Yukon scope. Field of view of the scope is good as the magnification is only 3X: fine for most purposes.

But for actual photography I have reverted to visible light, principally so I can autofocus the camera rather than depending on pre-focusing on a baited site or similar substitution for free action. The Fenix TK 32 (2016 update) torch I use has a very powerful white beam which will autofocus out to 400 yards in ideal conditions but at ranges that will allow flash to function effectively - say within 50 yards - I can use 3 lower power steps or even switch to red or green lights, both supplied by additional LEDs that are included in the torch. The red and green also have 2 steps of which the lowest is ideal for mice etc within a few yards. I use the higher step red all the time for foxes outside my front door. I've built the lot into a single hand-held camera rig.

Strong white light is not ideal for photographing at night. The same tapetum lucidum that enables you to find creatures causes eyes to flare like headlights if you hit them with max chat of torch or flash. Flash settings I use are invariably turned down by at least one full stop on both camera and flash. I can always turn the light level up again in post production, but flared out eyes are nigh-on impossible to deal with. So its in your own interest to use as little light as you can get away with.

I've never tried a thermal device. They strike me on the basis of others' reports as good for finding, no use at all for ID and not much fun for watching.

John

 

[Hauksen]

Hi Peter,

I've found a meadow with multiple Short-eared Owls hunting around, starting a little before sunset—they're partly diurnal—and sometimes expressing their unhappiness with the Northern Harriers still flying around from the day shift.

Awesome - in my limited experience, they might stay for quite a while if the hunting is good. I could have used a thermal imager even there, though - the owl's camouflage worked incredibly well. They could sit there, not so far away, right in front of you, amid the dried winter grass, and if you blinked, you'd have lost sight and try as you might, could not pick it up again until it showed its eyes

Regards,

Henning

 

[Hauksen]

Hi John,

Owls also give eyeshine. You get eyeshine from the near-IR torches as well as from visible light.

Ah, thanks a lot for confirming this!

I thought they would, but after hitting the "Submit Reply" button, I was beginning to doubt myself as I had never actually tried it

Regards,

Henning

 

[Peter Audrain]

They could sit there, not so far away, right in front of you, amid the dried winter grass, and if you blinked, you'd have lost sight

Yes, it's amazing how well adapted they are. (Incidentally, I wonder why human camouflage looks nothing at all like birds'—we've reinvented the wheel repeatedly with this, it seems.) It's also amazing how much evolutionary convergence there has been between them and Northern Harriers—the females even look like them!

So now I'm wondering if I could find them more rapidly and in greater numbers with a FLIR Scout. I guess I could. But on the whole I think I want to Wait For The Next Model—the current model really is so low-resolution, while still being just pricey enough not to feel like a defensible impulse purchase.

I'd love to hear more about other people's setups and experiences with sub-$1000 solutions for night vision and thermal bird-finding.

 

[Krissse]

Binoculars are really expensive, so the popularity of Night Vision Monocular is not without reason. I used Solomark Night Vision Monocular to shoot video of animal activities at night. It is very cheap and suitable for newcomers like me.

 

[marcsantacurz]

This is an interesting and informative video that compares a Sony A7SII vs a PVS14 Gen 3 light amplification tube. The video says they cost about the same ($4k new, $3k used), but nowadays the Sony is only $2k new plus lens (about $200 for the lens they used, you can get faster lenses too). The PVS14-3's I see are still in the $3k - $4k price. The did modify the A7Sii to remove the IR filter.

The takeaway is that if you have a clear quarter moon or more, they are pretty close and you get color.

Marc

 

[Dave Boyle]

I recently got a Helion XQF38 thermal imaging scope, which is quite a bit cheaper than the XP38 but doesn't have interchangeable lenses, has a slightly lower resolution image & doesn't magnify below 3.1x, whereas the XP38's minimum magnification is 1.9x. I got it for work, which will mainly be scanning across valleys looking for petrels dropping in to forest & I think it will be perfect for that, just need to wait until September for the birds to come back.

I recently tried it out at Frasers Hill & was amazed at how good it was for picking up birds, even in the tropics roosting passerines shone like beacons out the trees - the night I tried it I didn't see any mammals, but it was full moon but I think it would be amazing for picking up owls, especially small scops owls as you will be able to find them without having to use a torch & disturb them, although obviously no good for id or photos

 

[wllmspd]

Night vision lacks colour and so can make it hard to see things that can blend i with their surroundings of not moving, think deer, owls. At least foliage appears white in near-IR, which helps make things stand out a bit better. Thermal will help with alive critters (as long as warm blooded). Both thermal and night vision need fast optics, so seeing long distance or with detail will need big (expensive) lenses. I am sort of ignoring the “active” type where you use high power (invisible) LED and a camera that is sensitive to near-IR.
The A7S can do amazing things, but night vision allows you to safely walk about the place at night. I’ve used mine to observe the annual nocturnal deer rut, watch badgers having their dinner.. Gen2 is where the performance starts to get quite useful. Like walking about under heavy tree cover with no moon about. For astronomy you only want Gen3 and new prices seem to be >£4K. The night sky with a good intensifier is totally amazing (gets better with the addition of filters).
Pulsar has just released some newer cheaper models built around a sensor with smaller pixels (so smaller lenses needed- where most the cost comes from), the axion xm30 looks the best value at the moment, on my wish list (after many years sitting on the thermal fence). It will be best for spotting invisible stuff that you can get closer to and use other stuff to ID. I have the first Seek phone thermal plugin, OK for big obvious stuff and things around the house, but no good for detail and stuff in the distance. I’d avoid any thermal <£1k and <300pixels across.
Thermal won’t be any use for safely walking about the place, unity power night vision is what you need for that.

Peter