Date: 10/5/25 10:14 am From: Michael Fogleman (via carolinabirds Mailing List) <carolinabirds...> Subject: Re: thermal monocular
I have a Pulsar Telos XP50. It ain't cheap but it works great. It has a
640x480 pixel sensor with a 50 Hz refresh rate. It can supposedly resolve
temperature differences down to 0.015 degrees Celsius. The battery life is
fantastic, it can last ~8 hours on a single charge. It's weather proof and
generally very robust construction and feels good in the hand. It can take
pictures and record videos. It has a mobile app that can show you what the
scope sees and control it.
I used it to find those Chuck-will's-widows earlier this year. No way I
would have found them with the monocular.
If you know of a screech owl nest cavity in the breeding season, you can
usually pretty easily find the male roosting nearby using the monocular.
Speaking of cavities, you can usually tell if one is occupied or not due to
the heat.
Sleeping raccoons are a common find.
I found a very young fawn bedded down really close to where I was standing.
Completely invisible to me without the monocular.
I've had many "accidental" finds while looking for other things. A black &
white warbler nest, a white-eyed vireo nest, a chickadee nest in a cavity,
a very young fledgling sitting dead still in the bushes, etc.
The scope works best on fully cloudy days, or just after a rain, or at
night. If it's cloudy or rainy, most of the landscape is at an even
temperature, so then the animals really pop out. If it's sunny, everything
is at uneven temperatures and nothing stands out anymore. This is
significant - if it's sunny out I won't usually bother with it at all.
As far as how you go about using it, you can just carry it around and
inspect things that you think might be interesting (like tree cavities) or
you can sweep large areas looking for whatever. It's a fairly narrow field
of view but that's good if you hope to find small heat sources that aren't
very close up.
Michael Fogleman
Cary, NC
On Sun, Oct 5, 2025 at 12:05 PM Trevor Sleight <carolinabirds...>
wrote:
> Hi Derb/ list serve,
>
> I’d recommend searching for episodes of “Naturally adventurous” and “Life
> List: A birding podcast”that discuss thermals. Neither goes into the
> technical side of things but both are informative. One important takeaway
> is that thermal birding is its own pace and style of birding that requires
> an adjustment just like someone birding with the intention of taking photos
> birds differently than someone with just bins. I’d also recommend the two
> podcasts in general in addition to better known ABA podcast by Nate Swick.
>
> S4E28: Thermal Imaging Devices as a Natural History Game-Changer
>
> Naturally Adventurous
>
> Feb 11, 2024 • 49 min
>
>
> Comparing thermal scopes, Hurricane Helene effects, and the beauty in the
> unknowns on pelagics
>
> Life List: A Birding Podcast
>
> Sep 30, 2024 • 1hr, 5 min
>
>
>
> Happy birding,
> Trevor Sleight
>
> On Oct 5, 2025, at 11:41, Derb Carter <carolinabirds...> wrote:
>
>
> I read in trip reports that birders are increasingly using thermal
> monoculars for nocturnal birds and mammals. Interested if you have
> experience with these devices for this use and any recommendations.
>
> Derb Carter
>
>
