Thread: How important LRF in thermal handheld?

Originally Posted by Speargrass

Get a LRF buy once cry once, but and here's the but. You don't have always sacrifice specs/performance, if you want a work around here are some pointers.
The LRF is a real advantage but NETD is not the be all and end all neither are pixels but they are a performance indication for sure.
I would recommend looking at a low base magnification unit something around 1.5 to 2 power this allows you to identify hazards and terrain more easily and it allows rapid scanning and faster target acquisition in the dark.
A base mag of 3.5 or more can be a total PITA. Avoid it if you can in a hand held. In a scope it's a different matter I won't discuss that here.
Low NETD is a good guide to performance but it doesn't mean too much until conditions deteriorate most thermals detect, identify and recognise just fine until the weather packs in then a low NETD will perform better.
More pixels means better resolution but if you want higher magnification in more open country then every time you double the magnification you half the number of pixels you can use.
Some thermal units come in high base magnification because they provide better resolution for less cost but the downside is loss of performance with scanning and terrain recognition.
My work around in the early days was using the PIP and a graduated reticle in the PIP of the scope. Check if your hand held has a PIP and some sort of reticle or stadiometric range guide (pulsar do and so should others)
Most of my deer I shoot under 100 meters I used picture in picture (PIP) till I got LRF.
I would run the PIP at 6 power and the base at 1.5. I knew from experience that if a reds brisket covered 3 hashes on the PIP it was under 200 meters. If your handheld has something similar it will work as a rough range finder too.
This technique won't work on rabbits because their size varies so much.
Hope this helps.
Edit to add your going to keep that thermal LRF hand held in your vehicle everywhere you go and it'll replace your current range finder 90% of the time but keep in mind no Germanium lens likes being pointed directly into the sun, ever.

All of the above is on point, I even find a 2.5 magnification a bit high for my liking when I am looking for rabbits in and around hedges.

Stadia range finding really stuggles with rabbits, as above they vary in size with age, but also from one stance to another. Any length of grass beyond putting green makes it hard to bracket them too.

Originally Posted by Speargrass

Get a LRF buy once cry once, but and here's the but. You don't have always sacrifice specs/performance, if you want a work around here are some pointers.
The LRF is a real advantage but NETD is not the be all and end all neither are pixels but they are a performance indication for sure.
I would recommend looking at a low base magnification unit something around 1.5 to 2 power this allows you to identify hazards and terrain more easily and it allows rapid scanning and faster target acquisition in the dark.
A base mag of 3.5 or more can be a total PITA. Avoid it if you can in a hand held. In a scope it's a different matter I won't discuss that here.
Low NETD is a good guide to performance but it doesn't mean too much until conditions deteriorate most thermals detect, identify and recognise just fine until the weather packs in then a low NETD will perform better.
More pixels means better resolution but if you want higher magnification in more open country then every time you double the magnification you half the number of pixels you can use.
Some thermal units come in high base magnification because they provide better resolution for less cost but the downside is loss of performance with scanning and terrain recognition.
My work around in the early days was using the PIP and a graduated reticle in the PIP of the scope. Check if your hand held has a PIP and some sort of reticle or stadiometric range guide (pulsar do and so should others)
Most of my deer I shoot under 100 meters I used picture in picture (PIP) till I got LRF.
I would run the PIP at 6 power and the base at 1.5. I knew from experience that if a reds brisket covered 3 hashes on the PIP it was under 200 meters. If your handheld has something similar it will work as a rough range finder too.
This technique won't work on rabbits because their size varies so much.
Hope this helps.
Edit to add your going to keep that thermal LRF hand held in your vehicle everywhere you go and it'll replace your current range finder 90% of the time but keep in mind no Germanium lens likes being pointed directly into the sun, ever.

More pixels means wider field of view and lower base mag. Resolution comes from pixel pitch size and objective lens diameter. Most thermals use a 12 micron pixel pitch, with pulsar still doing some models in the old school 17 micron size. A larger objective lens will also increase resolution but at a cost of field of view and a higher base mag.
It’s worth trying different spec thermals to get the formula of base mag and field of view appropriate for your intended hunting.

Originally Posted by 55six

More pixels means wider field of view and lower base mag. Resolution comes from pixel pitch size and objective lens diameter. Most thermals use a 12 micron pixel pitch, with pulsar still doing some models in the old school 17 micron size. A larger objective lens will also increase resolution but at a cost of field of view and a higher base mag.
It’s worth trying different spec thermals to get the formula of base mag and field of view appropriate for your intended hunting.

All good points and great to tease out some technical info on thermals. Keep in mind that pixel pitch (the number of pixels) measured in microns offers different benefits. While a tight pixel pitch of say 12 Um will give you better resolution smaller pixels in a 12 Um unit are less sensitive to thermal radiation and don't "activate" as readily as larger pixels like say 17 Um. Some brands still use 17 Um because of this reason. So better detection at 17 um but slightly less resolution or better resolution at 12 Um and slightly less detection. Someone can sell you an expensive low NETD unit and it'll be all round better in most conditions all the time there's no replacement for performance but if your shopping around on a budget there's other things to consider. In adverse conditions (fog mist blowing in or wind) a higher pixel pitch 17 Um unit can equal or exceed a lower pixel pitch 12 Um unit for detection (not resolution though). It takes about 12 pixels to activate to send an signal/image to your OLED display. The software between the detection pixels and OLED display is getting much better in all brands but some are notably better. To be honest and 55Six will probably agree. If the weathers shit just stay home its hard enough work thermalling at night as it is and slippery ground in wet conditions make it even worse. Above all that is the paramount command "always positively identify your target". This post was for a handheld but it's worth mentioning in any thermal post.

LRF on thermal I've found extremely useful. I do a lot of vineyard and orchid pest control. My distance perception is pretty shit at night, 50m or 80m makes a big difference with .22LR.