OpticsTalk by SWFA, Inc. Homepage SWFA     SampleList.com
Forum Home Forum Home > Scopes > Rifle Scopes
  New Posts New Posts RSS Feed - Thermal Optics
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Visit the SWFA.com site to check out our current specials.

Thermal Optics

 Post Reply Post Reply
Author
Message
Marine24 View Drop Down
Optics Journeyman
Optics Journeyman


Joined: June/07/2010
Location: Monument, CO
Status: Offline
Points: 687
Post Options Post Options   Thanks (0) Thanks(0)   Quote Marine24 Quote  Post ReplyReply Direct Link To This Post Topic: Thermal Optics
    Posted: January/26/2018 at 13:25
Looking for some recommendations/explanations when it comes to thermal optics.

I'm trying to convince myself that I really need one but it is definitely a different world.  Other than a short time behind a PAS-13 in a former life, stick time with thermals is limited.

I can get my head wrapped around the screen resolution and refresh rates by thinking about them in the context of a computer screen or TV.  Core size seems to be a function of the size of the housing.  Smaller core size, smaller thermal scope.

Difference between optical and digital zoom is also understood and the consequences of using the either zoom and the inverse affect on resolution.

I'm leaning more the clip on route just for the flexibility but trying to understand a few things.

- Objective size.  I see thermal scopes ranging from 19mm to up to 100mm objectives.  Field of view I get but I've also seen comments about the larger objective helps with capturing more light.  What I don't understand is how light factors in to a thermal optic.

- Magnification - Given that zooming in on a target causes the screen on the thermal optic to get pixelated (not sure if that is a word) or grainy, what is the point of some of the high magnification thermal optics.  Is there a point where magnification is no longer useful?

- Clip on use - Mating a 40 or 50mm scope to a clip on seems odd given the difference in objective size and eye piece on the thermal.  Is that a problem?  Need to put a hood of sorts between the two or is it best to use a smaller objective (24mm) scope with a clip on thermal optic?

Any other considerations I should take in to account when thinking about thermals?

I'm just trying to educate myself at this point and haven't looked at certain manufacturers or models.
Back to Top
Rancid Coolaid View Drop Down
MODERATOR
MODERATOR
Avatar

Joined: January/19/2005
Location: United States
Status: Offline
Points: 9318
Post Options Post Options   Thanks (0) Thanks(0)   Quote Rancid Coolaid Quote  Post ReplyReply Direct Link To This Post Posted: January/26/2018 at 14:22
I use thermal quite a bit, but always in a support role to conventional NV, whether helmet-mounted or clip-on. I’m not a huge fan of clip-on thermal, mostly because it is unnecessary after target acquisition and identification, and because thermal scopes and clip-one are crazy expensive.

That, and identifying possible targets involves pointing s loaded weapon at them.

I run a recon handheld flir with PVS22 and PVS14 with PEQ15.

Lastly, the cheap stuff is, if you have time behind good stuff, very disappointing. A friend bought the Sig thermal and it is so low res/low refresh as to be infuriating in real-world use.

What is your budget and use?
Freedom is something you take.
Respect is something you earn.
Equality is something you whine about not being given.
Back to Top
Marine24 View Drop Down
Optics Journeyman
Optics Journeyman


Joined: June/07/2010
Location: Monument, CO
Status: Offline
Points: 687
Post Options Post Options   Thanks (0) Thanks(0)   Quote Marine24 Quote  Post ReplyReply Direct Link To This Post Posted: January/26/2018 at 15:09
Primary use is pig and predator hunting at night, along with recon for hunts.  Budget right now is in the $4-6K range.  Thinking of a 640 resolution/30Hz system but sticker shock is an understatement.

Just to clarify, by clip-on I'm referring to one that is mounted in front of the scope or attached to the objective of the scope.


Back to Top
Rancid Coolaid View Drop Down
MODERATOR
MODERATOR
Avatar

Joined: January/19/2005
Location: United States
Status: Offline
Points: 9318
Post Options Post Options   Thanks (0) Thanks(0)   Quote Rancid Coolaid Quote  Post ReplyReply Direct Link To This Post Posted: January/26/2018 at 16:09
I am referring to the same. I prefer convention NV clip-on and use a thermal hand-held for target ID.  I don't like to point my gun at a thing till I know it is the thing I want to shoot.
Freedom is something you take.
Respect is something you earn.
Equality is something you whine about not being given.
Back to Top
Marine24 View Drop Down
Optics Journeyman
Optics Journeyman


Joined: June/07/2010
Location: Monument, CO
Status: Offline
Points: 687
Post Options Post Options   Thanks (0) Thanks(0)   Quote Marine24 Quote  Post ReplyReply Direct Link To This Post Posted: January/26/2018 at 19:56
True.  Night vision does have a leg up when it comes to IDing targets, but as usual, it is a trade off depending on conditions.

Silhouette of a pig in a thermal is pretty distinctive but can get confusing quick if the resolution gets poor and find yourself targeting blobs that could be a pig, calf or my dog who wants to get in on the fun. 
Back to Top
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar
EVIL OPPRESSOR

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 16337
Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: January/26/2018 at 23:19
You will never get great resolution with a thermal optic even remotely close to what you're used to seeing in even the lousiest conventional optics. But sharp resolution isn't what makes a thermal effective; detection and contrast is. I still think a halfway decent thermal sight is more effective than even the best NV because it renders extreme contrast between living critters and their surroundings, even when the critters are obscured by vegetation. 

For the past 8 months, I've hunted hogs with a FLIR RS32 1.25-5X 60hz thermal scope almost exclusively. Its resolution won't blow you away, yet its effectiveness has been nothing short of awesome in no small part due to its "InstAlert" color pallete feature, where critters within a basic "white hot" pallet are highlighted in red whenever they are within effective range.

I pretty much keep it on 1.25X all the time. Zooming in makes the image way too pixellated so I haven't found it to give me much better shot precision for that reason. Then only time I ever zoom in has been during initial sight-in and checking zero when changing ammo. When selecting a thermal optic's magnification range, I'd advise just considering whether the base magnification is adequate for your expected shot distances. I wish I had a 640X480 detector resolution instead of the 320X240, but I'm just not willing to spend over $5K. I pretty much confine my shots to 100 yards and under, and at those distances, I can clearly identify the animal species, discriminate between animals when bunched together, and make precise shots at vitals.

There's just no escaping the fact that if you want a really good thermal optic, you will pay uber $$$ to get it. I'm hopeful that prices will come down considerably in the near future so maybe some day soon we can get decent resolution for under $3K.
Ted


Money can't buy happiness... but it's much more comfortable to cry in a Porsche than on a bicycle.
Back to Top
Marine24 View Drop Down
Optics Journeyman
Optics Journeyman


Joined: June/07/2010
Location: Monument, CO
Status: Offline
Points: 687
Post Options Post Options   Thanks (0) Thanks(0)   Quote Marine24 Quote  Post ReplyReply Direct Link To This Post Posted: January/27/2018 at 09:23
Ranges for me are typically inside of 200 yards based on vegetation.  For day hunting, I prefer my 458 SOCOM which limits my ranges as well.  A 6.5G at night will probably be my primary rifle.

I can see dealers coming out with new stuff, which hopefully will help drive prices on last year's models down.  
Back to Top
Marine24 View Drop Down
Optics Journeyman
Optics Journeyman


Joined: June/07/2010
Location: Monument, CO
Status: Offline
Points: 687
Post Options Post Options   Thanks (0) Thanks(0)   Quote Marine24 Quote  Post ReplyReply Direct Link To This Post Posted: January/27/2018 at 15:31
As I understand magnification, every time you increase your power, you lose 1/2 of your resolution.  If you are running at 640 at 1X, at 2X you are down to 320 and so forth.
Back to Top
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar
EVIL OPPRESSOR

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 16337
Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: January/27/2018 at 18:25
Yes, that’s correct, because the optic is zooming digitally, not optically.
Ted


Money can't buy happiness... but it's much more comfortable to cry in a Porsche than on a bicycle.
Back to Top
Scrumbag View Drop Down
Optics Master Extraordinaire
Optics Master Extraordinaire
Avatar

Joined: October/22/2013
Location: London, UK
Status: Offline
Points: 4205
Post Options Post Options   Thanks (0) Thanks(0)   Quote Scrumbag Quote  Post ReplyReply Direct Link To This Post Posted: January/28/2018 at 02:21
Sorry if this hijacks the thread but what are people's views on the best value handheld thermal spotter at the moment?

Scrummy
Was sure I had a point when I started this post...
Back to Top
Marine24 View Drop Down
Optics Journeyman
Optics Journeyman


Joined: June/07/2010
Location: Monument, CO
Status: Offline
Points: 687
Post Options Post Options   Thanks (0) Thanks(0)   Quote Marine24 Quote  Post ReplyReply Direct Link To This Post Posted: January/28/2018 at 10:01
So is it accurate to say that resolution is best at whatever native resolution is for a particular thermal scope? Resolution below 160 is generally unusable?

Some of the thermals has impressive magnification ranges but expect most will be unusable given how resolution degrades.
Back to Top
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar
EVIL OPPRESSOR

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 16337
Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: January/28/2018 at 12:36
Originally posted by Marine24 Marine24 wrote:

So is it accurate to say that resolution is best at whatever native resolution is for a particular thermal scope? Resolution below 160 is generally unusable?

Some of the thermals has impressive magnification ranges but expect most will be unusable given how resolution degrades.

Yes, resolution is best at native base magnification. The only advantage to zooming in is in helping center the crosshairs on the target, even though the target will be a much less well defined "blob."

I don't know that I'd call sub 160 completely unusable, though I agree resolution that low kinda sucks. I guess it would depend on the size of the target and shot distance.
Ted


Money can't buy happiness... but it's much more comfortable to cry in a Porsche than on a bicycle.
Back to Top
Marine24 View Drop Down
Optics Journeyman
Optics Journeyman


Joined: June/07/2010
Location: Monument, CO
Status: Offline
Points: 687
Post Options Post Options   Thanks (0) Thanks(0)   Quote Marine24 Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2018 at 11:13
Thanks Ted. Always good info.
Back to Top
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar
EVIL OPPRESSOR

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 16337
Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: January/29/2018 at 11:16
You bet buddy. I'm hoping that Ilya will bring us some good news on the thermal front from SHOT.
Ted


Money can't buy happiness... but it's much more comfortable to cry in a Porsche than on a bicycle.
Back to Top
okc4956 View Drop Down
Optics Apprentice
Optics Apprentice
Avatar

Joined: October/13/2009
Location: Oklahoma City
Status: Offline
Points: 135
Post Options Post Options   Thanks (0) Thanks(0)   Quote okc4956 Quote  Post ReplyReply Direct Link To This Post Posted: April/28/2018 at 08:59

 This is great info.  I've been looking into Thermal as well.  I've been looking at the Pulsar Trail XP50 and it is a pretty nice unit but I never knew what the ratio of loss of image to zoom was but that really makes sense now that you said it.  I looked thru one the other day and resolution was great at base power but really got crappy as you increased the zoom.   Those units are about 5k too.  They are supposed to be coming out with one with a built in rangefinder.  I think that would be very useful, tho my dealer tells me it will add about 1K to the cost.  The only thing I'm wondering about is the pulsar unit only has the 2 color modes, white hot or black hot.   Still pondering but this is very useful info!

Thanks.

Back to Top
orane View Drop Down
Optics GrassHopper
Optics GrassHopper
Avatar

Joined: May/14/2018
Location: Iowa,Des Moines
Status: Offline
Points: 4
Post Options Post Options   Thanks (0) Thanks(0)   Quote orane Quote  Post ReplyReply Direct Link To This Post Posted: May/14/2018 at 03:27
The Flir ones are nice for the price, but the optics, etc. aren't weapon capable. I've been eye'ing their marine units for a while and its nice to see they're marketing the "scout" for land use. You might cobble a mount, but the units aren't made to survive the shock from recoil, etc. Be prepared to spend some serious cash for a weapon capable thermal. They are pretty nice and are useful 24x7 if you have the $$.
Back to Top
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar
EVIL OPPRESSOR

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 16337
Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: May/14/2018 at 05:53
???

FLIR offers several “weapon capable” thermal optics. True, the units designed to be handheld aren’t weapon capable, but they also offer thermal scopes that are.
Ted


Money can't buy happiness... but it's much more comfortable to cry in a Porsche than on a bicycle.
Back to Top
Rancid Coolaid View Drop Down
MODERATOR
MODERATOR
Avatar

Joined: January/19/2005
Location: United States
Status: Offline
Points: 9318
Post Options Post Options   Thanks (0) Thanks(0)   Quote Rancid Coolaid Quote  Post ReplyReply Direct Link To This Post Posted: May/14/2018 at 09:38
Link to a few weapon-mounted thermals here: (https://swfa.com/catalogsearch/result/?q=thermal%20scopes)


As said before, I prefer thermal for ID and conventional NV for shot-taking.  I've used a weapon-mounted thermal and it does indeed work well, but I am not generally using in areas where I can assume pointing a loaded gun at something to identify it will be a good thing.

Thankfully, the price of thermal is coming down, and new tech is on the horizon or immanently coming.

It is a bright, red-outlined world out there!


Freedom is something you take.
Respect is something you earn.
Equality is something you whine about not being given.
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.430 seconds.