Forget Visible Light! – Let’s Talk Infrared and Ultraviolet

In this post, I explained how the light spectrum that is detectable to our eyes runs from around 400 to 700 nanometers. The sensor in your typical digital camera can detect light waves from around 200 to 1,000, but it has a hot mirror filter to block out the light waves at the extreme ends of the range. Then, in this post, I showed what happens when you remove that filter from a point-and shoot. I also told you that I ordered some ultraviolet and infrared LEDs. On my last post, Mark comments that perhaps I could use a cellphone board camera or a I2C camera, as these seem to register the infrared light in a remote control. Let’s explore that a bit.

The ultraviolet LEDs I ordered are claimed to be 395 to 400 nanometers in wavelength. Lights in this wavelength should produce very little visible light if any at all. I think the manufacturer fudged the wavelength specs just a bit, as these shine quite purple to the naked eye. I have no doubt that they are producing quite a bit of UV light though. Without the proper tools to accurately measure wavelength output, I’d guess that the range on these is more like 395nm to 405nm. When I take a test shot of a UV LED shining on my wall with my unaltered AW100, you can see a blue hot spot but the rest of the frame reflects visible light.


The same shot with the full-spectrum Olympus comes out in a neon purple bath:


I have a little glass horse that sits at my workbench. This is a reproduction of a design that Jennifer’s family came up with generations back. This one was cast in vaseline glass, which is a bright green, uranium filled glass that emits a bright luminescent glow under an UV light. Here’s how it looks with the visible light camera with the UV LED on it:


And again, through the unfiltered eye of the Olympus:


The visible light green glow is rather shocking against all of that UV light! As Matt mentioned, a digital camera can ‘see’ the light emitted from the IR LED in a remote control, but it can’t see much of it. Check out this side by side between the modified and unmodified cameras:

The infrared LEDs arrived today, and here is one shining on my wall through my stock Nikon:


Clearly, there’s not much going on there. Near the center at the bottom of the frame, note the faint red glow of the LED itself. These are even less visible to the naked eye. Through the UV-seeing Olympus though:


We get quite the wash of fuchsia. Just for giggles, what effect, if any will the IR light have on the vaseline glass horse? Here it is through my Nikon:


It wasn’t completely dark, but it was dark enough in the room that the camera didn’t want to focus. But through the Olympus:


Here is a picture of the view screens of both cameras, pointed at the horse, with the IR LED trained on it:


Microcosm Overlord and I are going to build a dual IR/UV light array that I can tote around for some further testing instead of being stuck at the bench. I fully expect to have some fun results to share. With any luck at all, perhaps I can have the array usable in time for Phlegmfest!

A Bump in the Road

If you’ve been reading my rantings, you probably saw my initial step into full-spectrum photography. I’m really looking forward to building my own full-spectrum homebrew trail camera, but the Olympus model I modified isn’t supported by any of the board manufacturers. Of the thirty-five or so models that are supported, they list Nikon’s L10, L11, and L12. Since Jennifer and I have pretty well gone full nerd Nikon at this point, I thought that it would be fun to build a Nikon-based game camera.

I wound up purchasing a Nikon L14 on ebay for about $15 after shipping. When it came in, I took some test pics and then tore into its housing to pull the hot mirror filter. I saw a familiar rectangle of glass over the sensor, and began nudging it with my screwdriver. This one was quite a bit more secure than the last camera! It did wind up coming off, but in several pieces. Hoping that I didn’t break anything too badly, I wedged the camera all back together. It powered on and I took a few more test pictures.

Trees were green and it was not apparently picking up any extra light. Hhhmmmmm… So, I took the camera apart again. I’m not sure exactly what the piece was that I broke out of the camera, but it didn’t seem to do much of anything. Upon a second inspection of the internals, there seems to be in iridescent coating on the lenses inside the lens assembly. In other words, it looks like the lenses are self-filtered, and there’s not a filter that I can simply remove or replace. When I reassembled the camera yet again, it still functioned correctly, and Teen Bot showed interest in taking it on for his own, so I gave it to him.

I’ve been looking online at some of the other cameras listed by the control board manufacturers, and Jennifer has quite understandably requested that I attempt to learn what I can about specific models to hopefully avoid making the same mistake twice. I have found more info perusing forums and online resources, and of the thirty-fivish models listed, have found specific testimony from other human beings of about twenty of them being converted to infrared. Some of them even posted pictures! Seriously, there’s no way I could have seen this coming. Besides that, it was a $15 gamble, and Teen Bot got a nice point-and-shoot out of the deal. I’d say we’re still doing well.

Oh and, I’ve pretty much decided that I’m going to get a Nikon D200 when we can afford it. I found a tutorial on a full spectrum conversion for it, and I think I’m going to take a crack at that myself. I’m feeling a little less gun-shy about modding cameras at this point. The Olympus is fun, and has produced some cool images, but it has always had a color-bleed issue which has only been exaggerated with the full-spectrum mod. Many pics aren’t showing much visible coloration, and I believe it’s a limitation of the camera itself.


There are standard items that I keep in the back of whatever car I have. Among these items you will find bottled water, a knife of some kind, first aid kit, emergency blankets, and some basic tools. Many of my normal friends think I’m weird because in the trunk of the Tactical Assault Compact Sedan resides one of these:

Folding shovel 002

“Why in the world do you keep a shovel in your trunk?” they ask me, in much the same way they ask, “Why on earth do you always have a knife in your pocket?” when they need something cut or “Why do you carry a flashlight with you?” when the power goes out. These seem like rhetorical questions to me. “Why” indeed…


I’m not the only one who sees these as essential gear. When we got everyone together for COGS 2013, it was cold and drizzly. On Saturday, some of our guests asked if they could start a fire behind the firing line. Not only did I endorse such actions, I pulled my trencher out of the trunk and put it to use. And, another one was produced from another trunk. With two people running these bad boys, you can have a nice sized fire pit in no time flat. When Jennifer and I go camping, we’ll often forget some piece of gear. We have left behind our air mattress or pillows, or had to run to town to grab a case of bottled water. But, the folding shovel is always in the car. There’s far more that you can do with these things than dig fire pits though. It is pretty well accepted that the U.S. G.I. E-tool makes a great weapon in hand-to-hand combat.


Indeed, with two sharpened edges on one side and two serrated edges on the other, not only will they handily cut through soil and hack through branches, they would be better than harsh words in a self-defense situation. Granted, if I was rushed by a dangerous animal in the woods, I’d rather drop the shovel and draw my .45, but failing that, I’d be glad for the shovel! A friend described to me how to use one of these as a stool to sit over a hole to poop in the woods. I couldn’t find a good diagram on how to work this, so I drew this crude* comic for an illustration:

e-tool poop stool

These things are compact. They will fit in the spare tire well with your spare, or in your jack storage. In a standard cab pickup, they take up virtually no space behind or under the seat. Currently, we only have the one car, but when we add a second and then a third when Teen Bot starts driving, they’ll get their own e-tools shortly after acquisition. Now, when anyone raises an eyebrow as to why I should have one of these in the trunk, my standard response is to ask them why they don’t have one in their car!

*Pun totally intended. I used to get in trouble for drawing stuff like this in school. Please pardon my crappy artwork. I know it kind of stinks. 😛

Pink Trees & Other Delights

On Friday, I shared my musings about setting up a homebrew, full-spectrum game camera. Years ago, when we had a couple of 35mm cameras and a Polaroid in the house, we did happen through a couple of extremely cheapo digital cameras. At some point in time, Jennifer decided that she’d like something nicer. We wound up ordering an Olympus Stylus 600 for her.


This camera hasn’t been used in years, despite our best intentions. We cleared the XD card several weeks ago and found pictures from our last trip to Galveston, before it got blown away by the hurricane, just to give a little perspective. I’ve been wanting to try out a camera with no hot mirror filter, so I decided to hack into the Stylus (with Jennifer’s permission, of course). When I was a child, I was a creative yet hamfisted lad, and wound up ruining quite a few pieces of electronics in my attempts to mod them. Every time I tweak on my gear as an adult, I fear similar results. Even so, I pulled the sensor out of the Olympus:


And, I popped the filter off the sensor. From left to right, there’s the naked sensor, the hot mirror filter on its gasket, a bracket pad, and metal frame:


I got the camera all reassembled and confirmed that it functioned still, and took a couple of test pics:


Alright, so the color is a little off and the cat’s eyes are glowing quite brightly. This is hardly any unusual feat of photography. Hrm. I then did some test pictures in my bedroom with a black light. For reference, here’s my bedroom wall through my Nikon, lit only with the black light:


And then, here’s a similar frame through the modded camera:


It certainly sees more ultraviolet light than the other camera does! It’s safe to say that it’s picking up extra-human light ranges at this point. Full-spectrum camera plus black light and UV responsive materials equals psychedelic pictures:



As you certainly know, we’ve been having a stormy few weeks in Oklahoma, so I decided to see how the modded camera perceived our storm clouds in comparison to my Nikon. Here’s the skyline from the unmodded camera:


And in full spectrum:


The world goes from gray:


To a stunning display of pink, purple, and blue:


The real shock though, came when I took pictures of trees and other green plants.


Are those cotton candy trees? What looks like this in visible light:


Transforms to this when you allow for infrared capture:


As it turns out, chlorophyll reflects a lot of infrared.



So much so in fact, pretty much everything under the canopy is washed in its pink glow.



Here’s one of the roses in our garden:



And jalapeño blossoms:



When there isn’t much visible light available,


There’s still plenty of non-visible light to catch with the CCD sensor.


So, will this make for a great trail camera? It looks promising. Sadly, as cool as the little Stylus 600 was when new, it’s about a $10 ebay camera now. Even the homebrew camera people don’t support this one. It seems that it was always a little finicky about focusing, and never took the best pictures. When Jennifer upgraded to her Nikon P80, it was really because the Stylus took terrible product photos. As an experiment in full spectrum photography, I’m calling this a win so far.

I have ordered a used Nikon L14 which will be the basis on my new, full spectrum game camera. I have also ordered 100 ultraviolet LEDs and 1,000 infrared LEDs. My brother and I are going to put together some light arrays. I plan on doing the hot mirror hack to the L14 when it comes in and continue my experiment using artificial UV and IR lighting in conjunction with the full-spectrum Nikon as well as the Stylus. This whole project has been so much fun and has produced such fascinating images that I’m seriously considering picking up a used DSLR, hacking it with the full spectrum mod, and getting a handful of various lens filters for different effects. I’m not in a position to buy just yet, but I have tentatively shopped a few models. Anyone out there have an old D40 or D200 with a 18-55mm lens that you’d be willing to donate to the cause? 😉 If not, I will likely start saving my pennies for one.

Camera Nerdiness

Since Jennifer and I are relatively new to hunting, we’ve gotten a lot of help from DanielS at Among the Leaves, who has been hunting for pretty much his entire life. He drove up to our property on several occasions to advise and help us reclaim the lost art that both of our families enjoyed only a couple generations ago. Daniel even loaned us one of his game cameras that he wasn’t using, a Moultrie I40. It has been in pretty constant use on the family farm in a location where the deer like to hang out.

The last time I changed out the card, the display was blank. I figured the batteries were depleted and took the camera home with me. When we checked the card, it was pretty clear that it had stopped taking pictures a few weeks earlier. Toward the end of the run of pics, there were blank files interspersed with the pictures, as if it tried to take pictures but the files didn’t save to the card properly. It seemed pretty obvious that it was batteries. I put six fresh batteries into the camera and found that the display screen was still not displaying. I could hear the camera click as if it was functioning though. Upon closer inspection, I found that it was not capturing images at all. The photo folder in the SD card was empty.

We’ve had some nasty storms lately, and I guess it was damaged in one of them. A little internet research showed that the screen is a pretty common problem with this model, which Moultrie will fix for about $40. Failure to capture images is a separate problem. Crap. Since I can get a brand new Moultrie camera delivered to my door for well under $100, this one is probably not worth fixing. Daniel was quite understanding.

Jennifer and I had recently discussed that we would like to add more cameras, but I guess we now need to work our way back up to a pair of them. In shopping the interwebtron for trail cameras, I kept seeing people referring to ‘homebrews’. My dad has spent much time on the back porch, homebrewing beer, but I didn’t have any idea what that had to do with hunting. A quick Google search dumped me into quite the rabbit hole. I have an insatiable desire to buy some $20 camera on ebay and hack it into a game camera.

Most game animal activity occurs in the dark. I have gotten a few daylight pics of deer, but nothing like the after dark activity! It seems like most of the homebrew camera guys rig theirs with factory or add on flash units, and just light up the deer when they least expect it. I can see how this would be effective, but it won’t work in my application. Since there are trespassers on the property from time to time, if they had a flash go off at them, I’m likely to have a camera stolen. Scaring the living crap out of some unsuspecting deer notwithstanding, my cameras have to be discreet because of two-legged critters. The commercial cameras take color photos during the day and infrared pictures at night with the aid of an IR LED array. I wondered how they did that.

Many trail cameras are put together in such a way that there is an articulated light filter over the sensor inside the camera. When the light sensor detects that it is bright out, the filter covers the sensor with a hot mirror that blocks out all but the visible light spectrum. When it’s dark out, the filter switches over to an infrared filter and lights up its array. What a marvel that they can use such an impressive instrument in a device that they can sell for so cheap! Well, as it turns out, all digital cameras have a sensor capable of recording light outside of our range of sight.

You see, the light spectrum that is detectable to our eyes runs from around 400 to 700 nanometers. Below 400 nm we get into Ultraviolet range before it give way to X-rays, and above 700 nm is infrared range. The sensor in your typical digital camera can detect light waves from around 200 to 1,000, but it has a hot mirror filter to block out the light waves at the top and bottom of the range.

In fact, the trick thing to do among some of the photography geeks is to have a camera shop rip out the hot mirror from your old DSLR and replace it with an IR filter when you upgrade your camera so you have a dedicated IR camera. In fact, there are some folks out there that have done similar hacks at home to cheaper cameras.

Of course, I wondered whether the sensor needed a filter at all. What would be the harm in letting it record visible light simultaneously with infrared and ultraviolet? A little more digging revealed that this is called “full spectrum” and is also practiced among photographers. It appears that when you go full-spectrum with a digital camera colors can get funky. I can live with this. If I built an unfiltered trail cam that ran an IR array at night, I’d get my day pics and my night pics, and not have an obvious flash that will scare the crap out of animals and direct meth heads to smash or steal my camera. This is a good thing even if some of the pics are a little trippy. I’ll just pretend the deer have been dropping acid.

This all brings up another good point. There are things that IR and UV are useful beyond what I’ve mentioned yet. And regardless of utility, it would just be fun to have a full-spectrum camera to tote around. I sourced some very affordable IR and UV LEDs and have conspired with my brother to make a light accessory. I believe that I’m going to build myself a full-spectrum game camera and also a full-spectrum point-and-shoot from one of the cameras we have laying around the Evyl Robot Empyre. If this is as much fun as I suspect, I’ll have updates for you later!

NRA 2013 – Thursday and Friday

Thursday, Jennifer and I got up early with the plan to pick up the rent-a-heap (as OldNFO calls it), with the intent of her taking our Compact Tactical Assault Sedan to work while I took the foster car home to load our junk, ready to drive once she got home from the office. She had a couple of loose ends to tie up before she could take off, but she was still planning to cut out early. The rental company jacked up our reservation and didn’t have our car by 7:30 as arranged. At that time, they offered excuses and said they could take a car to her office by nine. They didn’t have a compact, as we had booked, so they were going to upgrade us to a midsize. I dropped her off at work and took our CTAS home. At nine, she texted to let me know that the rental company had not yet delivered a car. She called and reamed them a new one, so they ‘upgraded’ us, once again, to a Dodge Avenger. Our original booking must have been for a two-door Speck with a three hamster engine. They got her the car at around 9:30, and we were on the road by ten. In all fairness, the rental company was extremely receptive to our multiple complaints and has made overtures to remedy the mishandling.

The drive was not terribly noteworthy, considering we drove through both Dallas and Houston. There weren’t too many situations in which I knew we were about to see some idiot cause a forty car pile-up because he was in such a hurry to rush up and tailgate the next driver in line or cut across four lanes of traffic with no signal, or both. Maybe I’m just growing patience with age. Thursday night, we met up with some of our friends for some Cajun food. Jennifer and I split a dozen oysters on ice, five pounds of crawfish, sausage, potatoes, and corn. Yum! Friday morning, we woke up at the butt crack of freaking dawn and headed down to the convention center. Parking was a veritable nightmare. If you don’t mind spending $30 to park your car for a day, it wasn’t bad at all, but that is extortion, IMHO.

The show was what I have come to expect out of a trade show. There were lots of pretties to handle and we got to meet many interesting people. Some of them are people that we have grown to know and respect online, others that we only knew by reputation prior to this weekend, and still others that were fresh introductions. Also, we had the opportunity to catch up with some old friends, if not nearly enough of them. But, that’s how these things go. It seems like no matter how much you try to pack into each day of the weekend, in the end you’re always short on time. Please do expect some pics and accounts of guns and gear, as well as more detailed stories, and it looks like we’ll have some extended test and evaluation stuff to look forward to. In the meantime, I’ll post some more updates tomorrow, and suffice it to say that it’s been an extraordinary trip so far.

Marketing Fail

Every now and then, I’ll see a store display that just stinks of some out-of-touch marketing mind doing something that they think will be clever, not taking into account reality or people or human nature. At the local office supply store, there is a Sharpie marker display that is set up as a try-before-you-buy affair. It is a colorful display with racks of markers in different colors, and at waist height, it has a paper scratchpad and a couple pads of Post-Its. One must be careful how they design a promotional store display. It is nothing short of laughable that whatever aforementioned marketing guru did not foresee the shortcomings in this otherwise clever marketing piece.

See, people can’t leave well enough alone. If you leave an opportunity to make havoc, someone will take you up on the offer. How many times have you seen a prank video based around the placement of a mysterious button, and the filming of passers by pressing it to see what will happen? Indeed, I would defy you to leave what appears to be a very large firecracker someplace with a lighter, and see how many people try to light it. It’s irresistible. As another example, on Sunday, one of the local grocery stores had a rack full of herbs. I could not help myself and had to do a little rearranging.


Are you going to the grocery store? Remind me to one who works there.
So, Sharpie has this great display where people can try out many colors of their permanent markers.


They even provided a little pad of paper for people to try out their markers on. There’s a sign over the paper that reads, “Try Me”. And surely, nobody would mark anywhere but the provided paper, right?


“Try Me” you say? Don’t mind if I do!

I’ve been watching this display for a while. When it first went in, although pristine, I recognized it for the degenerative folly that it would eventually become. Here’s part of the display which shows a picture of a little girl a few months ago:


And, more recently:


I <3 poop

LOL! Beware of the quips of marker wielding idiots! The differences are subtle, but clearly more artists have contributed as time has gone by. People even took the opportunity to mark on the shelving to the side of the display.


Here, you can see that someone wrote a greeting to the world not once, but twice, just in case the world wasn’t paying attention the first time. World, you’ve been greeted. And finally, there was at least one brony representing:


They at least had the decency to leave the message on one of the provided Post Its instead of defacing the display or store property. I realize that most of this graffiti is likely the work of under attended children, but it illustrates a part of human nature that never really goes away. As we mature, we learn to rise above it, but it never fades completely. We’ll always have that prankster that wants to press the button or rearrange the herbs or scrawl “I <3 poop" in a speech bubble on the Sharpie display. Note to all you marketing people out there; make your product labeling witty and humorous enough that your prospective customers won't want to deface it when their attention is drawn to it. awesomesauce

Because seriously, who would want to mess up a perfectly good jar of Awesomesauce?