Flir M24 with 640 core - my first impressions

I took my brand new M24 out last night for a 3 mile walk in the field. This thing is AMAZING! It is the most impressive piece of gear I have ever used in my life. I sold 5 of my M1 Garands and 5000 rounds of M2 ball ammo to fund this purchase and I couldn't be happier.

As a quick background note, I have hunted with my Gen III AN/PVS14 for a couple years. So, I am somewhat familiar with I^2 night vision. I am a complete newcomer to Thermal. 3 weeks ago, I purchased a 340 core Flir HS-324P. It was nice. But, I did not think it was $5000 nice. I also had some problems with the battery charging circuit. So, I returned it. I ended up buying the $7500 640 core M24 from the same people. It was well worth the additional cost.

My goal was to buy a unit that would serve two purposes - coyote night hunting and SHTF. Therefore, I thought it would be important to have 1X capability. The 640 core M24 is incredible in 1X mode. I can see much further and resolve much better than the 324P. The 2X and 4X digital zoom is where the M24 really shines. When I see something worth checking out at a distance in 1X, the 2X and 4X feature helps me really see what is going on. The zoom feature is the highlight of the unit. Even in 2X, the resolution is twice that of the 324P. In 4X, the resolution is about what the 324P is normally. I was looking at areas 700 yards away with ease. Weeks before, in the same field, I could not see anything with the 324P.

640 core = 307K pixels in 1X, 153K pixels in 2X, 76K pixels in 4X
340 core = 81K pixels

I plan to get a 2x or 3x lens in a month or two for hunting purposes. I was initially considering the HS307. But, the lack of 1X capability was a show stopper. With a 2X lens, the M24 will out perform the 307. Other things I like better than the HS-324P/307:

Fast turn on time.
Small size
More rugged
Easier to use controls

I wish it worked on rechargeable AA batteries. But, I can live with the CR123s. I think the SHTF role that I want it to play demands some sort of replaceable batteries. So, this is good.

There it is. I know I am new to thermal. But, I thought a review from a new guy would be helpful because there are more new guys than old guys in the thermal market. I figure my experience will probably mirror many other peoples first time experience.

Oh no there you go making me think about spending more money .



I haven't seen that math but it does really help to give you a idea of the clarity differences.

Terry had mentioned yesterday that with his PS32 he could not make out the antlers of a deer beyond a limited distance.
So my question to the OP is at what distance do you think you could make out a rack on a deer and I an not speaking of a
booner.
Interested in knowing if the 640 core M24 could be used for deer surveys as I already know it can be helmet mounted which is of interest to me.
Thanks

That is a hard question. Counting points on an antler would be difficult at long distances. I wouldn't even want to guess without trying it. I would guess that a 640 core Flir bioccular with the biggest lens you could purchase would probably be your best bet. I just don't know how far away my M24 would work.

So approximately how much for the lense?

7500 seems like alot but that is this arena isn't it?

come on september

I was told a 2x lens will be available in 30-60 days and be about $1K.

P.S. It's only money that I would waste on food, a mortgage, or other bills

Where did you purchase it?

I have a pile of night vision, and quite honestly I think if I sold most of it I would be within a stones throw of that price!

I bought it at US Nightvision. Matt was the salesperson. Very nice guy. He treated me well.

i have the hs 307 and it works good for what i do, Detect the critter then close the distance and make the shot with NV, however i was interested in the 640 core m24 which has a wider FOV but never could get anyone to confirm what the detection range was. I'm no thermal expert either but in my experience seems like the more narrow the FOV , the greater the detection range is, however was wondering if the 640 core in the m24 would offset my theory and actually have a greater detection range than the hs 307. I guess a good side by side comparison of the two would be great. Anybody done one?

Ben, here my thinking on how to estimate the difference between a 307 vs. the M24. I could not find hard data on the M24 either.

For a man:

HS-307
Detection 1319m
recognition 339

HS-324P
Detection 440m
recognition 109m

The M24 has a 19mm lens like the 324. And, at 4x, it is about the same number of pixels as the 324 (m24 is slighly less). Therefore, you can probably say it has about 3-4 times the range as the 324. That would make it

M24 4x
Detection 1320m - 1760m
recognition 327m - 436m

Add a 2X lens, and I think it will easily exceed the specs of the 307. The best part is that you have the flexibility of 1X, 2X, and 4X for quick scanning.

M4, i hardly ever use the 2x zoom feature on my 307 cuz its so blury and it detects animals pretty far in the 1x mode. What do you think the detection range of the m24 would be just useing the 1x and 2x zoom mode?

Does the M24 clip to a helmet, and/or does it have a weapon mount kit.

See the link below for info and pictures

http://www.ar15.com/forums/t_6_18/358675_FLIR_M24.html

Ben, I found the HS-324 2x feature to be blurry also. The 2x feature on the M24 is extremely good. Very useable. The 2x on the M24 is better than 1X on the 324. In my opinion, the 4X on the M24 is iffy. It blurry and of little use. I think the 4X will really shine in 4X when I get the 2x lens.

I think you could detect a man to 900 yards in 2x with the M24. It would be great to put the two units (307 and M24) side by side. I would bet the 307 is better than the M24 without the 2x external lens. With an external lens, my money is on the M24.

Thanks for the info M4. I've been thinking about selling my 307 and upgrading to a 640 unit. Hopefully someone can post some video of a side by side comparisons.

The M24 works great with a helmet mount,on a side note I have mine connected to a SPI X-DVR and is really brings the details out. and still gives you your prereferral vision and you can use the scope as almost like a para scope in a SHTF situation. This is a great unit and you don't realize how much it shines until you take it out in the middle of no where and see how much activity is around you.

Thanks for the review. Good info!

A correction on the above though. 640x480 on 2x = 320x240, same as the HS-324, 4x is 160x120.

Also, keep in mind that with a doubler lens, the info has to go through twice as much glass, so it wont be as good as a unit with only that higher mag lens. You can see it here b/t the middle and right video. HS-324 w/ doubler, which in theory should be very close to the HS-307 on the right...but you can see the detail suffers a good bit.

FLIR Comparison

Anyway, in spite of my nitpicking, it sounds like a really fantastic unit!

It is also my understanding that the "glass" is actually Germanium and that the losses are very low. I see some variation in the clarity in the comparison video. It could be a screen brightness setting. To me it seems small. The FLIR technical rep said there should be no perceivable difference in clarity using two germanium lenses because of the low losses.

From everything I have read and heard at 1x the res is 640x480 at 2x is goes to 320x240 and at 4x goes to 160x120 not sure how accurate that is for sure. but the guy I talked to seemed to know his stuff so.

I think you guys are right. Thanks for setting me straight. So, the M24 really just doubles the distance performance of the 324P when you use the M24 in digital 2X mode.

M24 in digital 2X mode

Detection 880m
recognition 218m

I guess for the M24 to rival the 307, the 2x lens would be necessary.

M24 in digital 2X mode with a physical 2X lens:

Detection 1760m
recognition 436m

I'm still learning...

I didnt mean to write a book, but hopefully someone finds this useful.... It's too long to proof for typos, so forgive them please.

FOV is directly related to magnification, how close an object appears. For some reason most thermals aren't labeled 1x, 2x, 4x like scopes and binoculars. I noticed that the new ATN scopes are being labeled that way which I think is smart, bec most people dont understand what they would be getting with X FOV, but everyone understands 3x and 1x. This drove me nuts trying to figure out early on.

The ATN scopes are labeled as such:

F.O.V.: 24°(2X) 15°(4X) 10°(6X).

I'm no optics engineer, but a couple years ago I looked around at DAYLIGHT binoculars for FOV specs vs "X" power to get a feel. On a say a 6X fixed power binoc, the FOV is NOT the same on all models, but it it pretty darn close. I think it has to do with the size of the lens or something.

Would you buy 2x binoculars to try to look at something 500 yds away? Of course not, but the thermal FOV spec is confusing to most people, not to mention everything else about thermal that is hard to get a grasp on initially. Most people buying them haven't even used one before. Tough spot to be in for an expensive purchase.

Then consider that the resolution of your eye through a glass lens with vis light is WAY higher than even 640x480. So 2x magnification with crappy resolution. You would not expect to make out much detail at much of a distance, vis or thermal.

But of course the beauty of thermal is that even a blob or a 6x6 pixel dot is useful, you know something hot is there.

Anyway, as far as the magnification goes, I think you could assume the ATN numbers above are a typical comparison for of the units we've talked about when trying to relate to how much magnification a unit has in comparison the the vis optics you're well accustom to.

For comparison, I a grabbed a random 6x binocular off Google. The FOV was listed as 420ft @ 1000 yds. If you do the math on that, it's 8.01 deg, So everything is in the ballpark of what we are expecting. Binoc images are round though and the FOV of a thermal is rectang, so it less vertically than horiz.

The M24 has a FOV of 24 Deg. or about 2X (This is the same as the image on the left in video)

With a 2x Mag, that drops it to 12 Deg and about 4X (This is the exact same as the image in the middle in the video)

The 307 on the right is 7deg FOV or about 6X (video on the right)

The M24 640x480 with a doubler AND 2x zoom on, would be 6 deg FOV, So the magnification should be about the same as the 30 7 on the right. The resolution will also be the same, 320x240. So in theory it should look almost identical to the 307 on the right.

The other factors are:

1.) The quality of the lens. Just like vis lenses, quality varies a lot (Zeiss vs. Tasco) There is no way to put a number on this. I talked to an engineer at FLIR and he told me they grabbed the 307 lens from a fairly high-end security camera of theirs and put it on the HS housing to make the 307 due to range complaints on the 324. He said the lens costs an "order of magnitude more than the 324 lens." Sounds like what we see in day optics.

2,) The sensitivity of the core. Can the core see the difference b/t 0.1 deg or does it take 0.5 deg difference for it to show up on the little screen you look at?

3.) The sophistication of the processing of the data received from the core. Unlike day binoculars. The image is built by a processor and displayed on a screen. The better the software, the more they can do with the same lens quality and same thermal sensitivity.

So back to the above scenario. You are going to see some losses with a doubler. Just like putting a 3x AFOCAl on a PVS-14. How much? No idea, would just have to try it. I expect it would still look good and be a very useful accessory and a great combo. I would imagine the lens quality is prob pretty darn good on the Recon series since it was intended for the military. I would guess is it better than the HS-324 but that is just a guess. The Military is very cost conscious too these days.

It seems reasonable to assume they have prob improved the processing tech and the sensitivity of the core, but that is just my assumption.

Bottom line, my guess is that an M24 648x480 with a doubler on 2x zoom will prob be in the ballpark of 307 performance, but I bet resolution and sensitivity will suffer a bit from the multiple lenses.

The great thing is that you have the option for wide FOV and a nice compact package. If I was buying right now, this is what I would be looking into. I know someone who has a 640x480 M24, if he gets a 2x, we can compare with my 307, and I'll do a followup.

The extender lens I have for the m24 is a 3x and it looks great, there is some loss with the 3x on but it looks to be very minimal. This is a very useful accessorie for the m24 now to look for a helmet mount that will work.

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