I saw some comments that that 850nm '*may* be somewhat visible to animals? Does this vary species to species? My particular interest is rodents although would like to better understand in general. Are 850 and 904 the most common IR illuminator wavelengths?

This animal seeing ir thing just keeps going...here is my two cents...just turn the ir on off quickly or cover with your hand...if the animal has been hunted before there going to be spooky of anything...

For your question about wavelength ....Im going to use my lifeline and call on Dr. Skypup to answer this question...happy thanksgiving

Sounds like Wahoo is getting set up big time for night rat sniping!!

Nope, they do not see anything visible over 720-740nm, so both 850nm and 950nm are totally completely absolutely 100% INVISIBLE. (Period)

End of Story.

Now, that does NOT mean your IR Illuminator is putting out PURE 850 or 940nm as an LED derived IR source wavelength scan is a Bell Curve with the main peak at the published wavelength.

If you don't know what a Normal Bell Curve is, look it up...

If choosing between two IR torches, does either a 850nm or 940nm represent a better selection based purely on wavelength?

Wahoowad....

I will throw in my 02.

I had a Luna 805nm emitter that was a great long range unit but produced a bright red glow at the unit. You could not see the beam but you sure could see where it was coming from. Needless to say it always gave away my position. I sold it and started searching for something in the 850nm range and up with a focusable lens. I wanted a focusable lens to get rid of IR feedback from surrounding vegetation. If you hunt in wide open areas this may not be a concern.

It seems to me that the further away from the visible spectrum you get the less detectable the source of the light is. (Higher frequency better) if this is incorrect , Skypup will elaborate. It also seems to me that the further you go into the far IR spectrum the more power the unit needs for long range use. I assume that's because it's getting further away from the visible range.

You have not stated what NV unit you are using the emitter with or what you are hunting. (Range?)

If you are NOT worried about IR spill and feedback the 3.4W EagleTac IR is a very good unit for closer ranges...especially for the price.

http://www.illuminationgear.com/14322/26971.html

If you need a focusable unit for longer ranges look at the Torch Pro from TNVC. This is the unit I use now for yotes and hogs. It is a 805nm unit but due to the lower power and design I have not noticed any detection issues like I had with the Luna unit.

http://tnvc.com/shop/tnvc-torch-pro-infrared-illuminator/

If you will provide more specifics about what info you need you will get better feedback. Post links to the units you are considering. Also use the search engine and type in what you are looking for. There are tons of older threads with good info.

I am mostly trying to learn and understand the specifications on some of the cheap IR flashlights and replacement bulbs I see for sale. Some are 850, others 900+.

Kind of got into this issue researching a possible rip-off for an infrared torch I bought. I purchased this "5W" infrared torch off eBay: http://www.ebay.co.uk/itm/280837404094?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

It arrived and provides marginally adequate IR illumination out to 20 yards or so (for my night vision camera).

Today I came across these infrared drop-in replacements.

1 watt: http://www.ebay.co.uk/itm/280841096537?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649
3 watt: http://www.ebay.co.uk/itm/China-Made-3W-...=item5d2e3208c8
5 watt: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=280845340730&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en

The 1 watt unit shows a single emitter in the bulb. The 3 watt unit shows 3 emitters in the bulb. The 5 watt shows 4 emitters.

The unit I purchased only has a single emitter in the bulb. How can I tell if I am getting 5W output? I am wondering if they call it 5 watt but simply send you a 1 watt bulb and think you'll never know the difference?

Wahoo.....

You just gave me Excedrin Headache #468.

you asked for more specifics

There is another post on here where there is a lot of debate on whether or not coyotes can see IR light. The answer is no they cannot see the IR beam emitted on them or the ground around them just like you can't see it. But yes they can see the "source of the IR" being emitted from your IR device just like you can see it. The 940nm units that I have tested generally do not perform as well as the 850nms or lower as far as brightness and range but they do put out a slightly less noticeable IR source. IMO I don't think the slightly less IR source emission is worth the lower performance of the 940nm units. I also tested a 1080nm IR Laser unit once and could only barely make out the beam itself with Gen 3. So that was a no....go and R&D expense writeoff for the company. Kevin

The reason 940nm does not work so well with night vision is the Gallium Arsenide Image Intensifier does not do well at wavelengths much above 900nm, meaning that it is NOT going to intensify IR wavelengths higher than 900nm.....



This above graph shows the human visual spectrum from about 400nm (purple) to about 720nm (dark red) that we see during the daylight (curve on the left), compared to the light frequencies that are picked up by the PVS-14 image sensor at night from about 600nm (green-yellow) to over 900nm (IR) (curve on the right), everything over 720nm is invisible to us as it is infrared light....

The GEN III Image Intensifiers work best from 720nm to 900nm as shown in the graph of the Intensifier Tube Amplification Range. Gen I & GEN II are both different than this GEN III graph.

Just another outstanding scientific reason why you would want an 850nm IR laser or IR Illuminator to use with your NVO, beside the fact that it is 100% absolutely completely INVISIBLE to every creature on Earth that you shine it at....

Thanks for posting this again Skypup. This is the true facts what is happening with the spectrums of light.

But wait, Vic, I just read somewhere today on the internet that the world is ending before Christmas of this year, the Earth is reversing it orbit around the Sun, rodents have X-ray vision, coyotes have IR vision, Yassir Arafat's radioactive Zombie corpse is rising from its grave in Ramallah????

With so much awesome information on the internet, exactly what are you to believe?

I have had good results with putting butler creek scope caps over my ir torches to reduce the red signature at the light itself. It works VERY well and the light still performs great.

It is? Uh oh. I also heard the other one on the SH forum that folks better buy NV from a certain person because the EM Nuke war is about to happen any day now and you should not be left in the dark.