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2015 Blackflash Revisited

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Okay Hag's House members, I'd like to start a discussion on image capture illumination. I do not want to start a debate comparing white flash, low-glow, no-glow, red-blob burst, black flash, etc. Also, I'm not a video guy, I prefer still pics. I have a feeling though we might need to learn a few lessons from technology adopted in the video world. In other words, "how to capture an illuminated image in the dark without a detectable flash or glow".

 

We should be able to do this, right? Commercial cams like Reconyx, Browning, etc are utilizing black flash tech. (I actually don't know as I've never bought one...I just threw some names out there..) I'm considering a non-detectable "flash" at the 940 nm wavelength. I don't think 850 nm is good enough, but maybe?

 

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What is holding us back? Money? Access to materials? Programming?

 

Is it the image sensors that are holding us back? I realize we maybe limiting ourselves with hackable point-and-shoot cameras?

 

Where are companies like Reconyx getting their LEDS, image sensors, fixed lenses, sd card writers, etc?

 

 

Members, please share your thoughts and experiences. Maybe as a team we can start a project and develop something?

 

I'm willing to take the lead and fund some development work.

 

-Paul

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I build blackflash video cameras every week using the DXG125. Completely blackflash using 940nm leds. Actually the exact led that reconyx uses from the exact same supplier. Myself, EgbertDavis, and BowGod tested this stuff for over a year before we finally got it right. I sale the led arrays and drivers on my website. I will be glad to answer any questions anyone has.

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Jim, have you by chance tried pairing one of your arrays with an IR camera? I know you are way past using the P32's. I would love to know how they work with one of them though. I recall in the past when people tried the blackflash with the point and shoot cameras the pictures were really fuzzy.

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Thanks for chiming in Jim. I know you've spent a lot of time testing the 940nm LEDs. In your opinion, could we pair the array with a point and shoot camera converted to IR as s2s suggested? Say an A503, pl200, w200, etc. I'm guessing you guys tried that? Turning the array on and off during image capture? Maybe these cameras don't see the 940nm wavelength very well?

 

Are there any new video cams that convert to IR lenses that you know of that take stills too?

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I have done a lot with the IR Leds and cameras. I have not paired up a p32 with IR Leds but did do a 503 with 950nm LEDs. The thing I like about the LEDs are that they do not consume any battery power until used. That means I can sometime get by for a whole season with one set of batteries for the LED array. The largest problem is the arrays usually need to be very large to put out enough light for the camera to see well and give you a good picture. Usually what happens is the picture is dim enough that the iso end up being real low and the exposure takes a long time resulting in blurred pictures from the animal moving. This has not been a problem for me because I can usually tell what the animal is and what time it is moving which is enough information for hunting.

 

As far as the ccd image sensor in cameras, I have tested them out to 1000nm LEDs and the cameras could all see the light from the array. Trying to get blocking material for a flash I had picked up some lens for the dslr that blocked up to 950nm and tested that for flashes. It worked but watching the flash go off I could see small amounts of light bleeding through areas that I had not sealed perfectly. Here is a link to the type of material I used with the flash:

http://www.ebay.com/itm/52mm-950nm-Infrare...ooAAMXQhpdRvuDo

It was actual glass and not plastic so you need to be extra careful cutting this or it will shatter.

 

With my 503 test camera, I noticed that the deer did not see the array light but they could hear the camera shutter on the camera that the 503 makes. The deer would stand in front of the camera for 4 or 5 minutes at night bobbing their heads trying to figure out what was making the sound and if it was a danger. I think the flash would be the same in that even if it was completely invisible the flash charging would make that high pitch sound alerting the deer that it is there.

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The DXG125 takes still photos as well as video. I have built several units using the spare opto on the Critter Getter PRO that will do color still pics during the day and ir blackflash video in 720p HD at night. The Sony point and shoots do not see the light AT ALL!! PERIOD. Have not tried a 503. The three of us spent and wasted so much money playing and testing this stuff it was crazy. With Rick Gray's help we PERFECTED the led array and driver. It works great. But the dxg is still the camera of choice in my book. And since I done a tutorial for everyone on how to get the lenses perfectly level they should be fairly easy for anyone to build.

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Great feedback gentlemen. Happy thanksgiving! Glad to hear some of the point and shoots can see different wavelengths. Sounds like the Sonys may struggle.

 

I'm thinking about doing a LED build, just need to do a little brainstorming. I've been eyeing up this Pelican 1170 case, looks like it will give me more room to experiment with adding an array.

 

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Great feedback gentlemen. Happy thanksgiving! Glad to hear some of the point and shoots can see different wavelengths. Sounds like the Sonys may struggle.

 

I'm thinking about doing a LED build, just need to do a little brainstorming. I've been eyeing up this Pelican 1170 case, looks like it will give me more room to experiment with adding an array.

 

Here is a dxg build I did with an array in it and the 1170 case. Case is nice and big with lots of space in there.

 

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Here is a look inside with everything in it. The case only opens 90 degrees so can't layout a whole picture. Just the battery holders are in the door section. The project box I think is the 6x4 size which holds the array. The array is the 30 of the 10mm 940nm with a 1000mah driver. This should give you an idea of how much space you will have to work with on the pelican 1170.

 

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If you decide to move ahead with testing let me know and I can send you some of my test arrays that I have built (no cost to you). You could try them with some IR cameras to see how they perform. Don't expect these arrays to be anything great. 2 of these arrays I only built for testing and have never used them in builds. The 30 led array is the same thing I have in the dxg camera and you would likely need 2 of these to work with any still camera.

 

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The 1010 led is bright for what it is but the leds are too close together and give a flash light effect. This setup may be the best hope for use with a still camera. It is using a pulse driver so the led is on for only a millisecond but has double the voltage across the led. This gives off a lot of extra light but is only on 1% of the time. The other 99% it is off and cooling. This happens 100s of times a second so to the camera and the eye the light appears to be on all the time. This is the same thing that the commercial cameras do. If this showed enough potential I could show you how to build the circuit up to build a larger array. I even used a picaxe in this one so you might be able to work code if needed. The picaxe does produce a flicker in the light though from time to time.

 

The black leds are the 950nm leds and again by itself is not very bright. The 30 led array could likely be hooked up to 5.5volts and survive without a driver for testing (if it did not - who cares since it did not cost you anything). Let me know if you would like any of these arrays for testing and I will send them to you. Each one is a little different and will need some explaining to get them to work for you.

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Rick, I'm liking what I'm reading! Thank you for sharing your thoughts. My gut reaction is to maybe concentrate on the "1010" type array with the pulse driver for pairing with a still camera. Sounds like you may lean that way due to the increased light output. Thinking about the possibility of expanding the footprint of that array type. How many LED's will get us proper illumination?

 

Does anyone know how many 10mm LEDs on average commercial cams use? The goal is to outperform commercial cams.

 

Thinking about powering an array... I would like to use rechargeable NiMH AA cells rather than the sealed lead acid rechargeable batteries. I don't have any experience with the SLA's, so maybe that's why, but also they seem cumbersome to me. In my opinion a good set of Eneloops AA's and a smart charger is tough to beat.

 

Thanks for the Pelican 1170 pics too. That project box fits in there perfectly.

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The pulse driver should be the brightest option but the most difficult to do. Current drivers and just hooking up LEDs are very easy. The 1010 array should run from 6 to 8 volts the higher the voltage the brighter the array would be. So that would likely be 5 or 6 nimh batteries to run the array. Each camera is going to be different so we will likely need to do some testing for proper lighting. The reason I have these test arrays is what I usually do is mount them on a board and go outside with the camera and turn more and more of the arrays on while taking pictures so I can see how the camera responds to the light. I am thinking this comes down to more what lens the company used and programming for the auto settings of the camera. I have not had the best luck setting a bunch of program settings on the camera like on the flash camera builds.

 

Most of the commercial cameras that I have seen have had between 50 and 100 5mm leds.

 

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I had a 503 ir that I could use for a quick test with the 1010 array that will show you somewhat of the challenge you are facing.

Here is the first picture. It is really dark. But if you look at the details of the picture it is using an exposure of 1/30th a second and iso 200.

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Here is the second picture. It appears much brighter but the exposure is 2 seconds with an iso 100. Really slow and would blur most any motion by the animals.

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These were taken just holding the camera and the array. I aimed it at the wall of the house looking down it just to give it something to bounce off of. The 503 is not know for being a good night picture camera without a flash. Looking at the fstop it is 3.2. For the dxg cameras we are get an fstop around 1.2 or so.

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Hmmm. There are plenty of challenges to think about here when trying to pair a point and shoot with an array. For example, I believe most digital point and shoots use the preflash to set exposure. But in my typical a503 builds with the vivitar 2800, I don't even drill a cam flash hole so I don't know how it 'sees' it's own preflash. So maybe my previous understanding is false.

 

Syncing the camera maybe difficult. For starters, I may have to think about providing a longer duration of light, then trim the duration down during testing and programming? Extra light just burns battery power, so I need to consider efficiency.

 

I'm taking a look at some additional camera options. Taking aperture into consideration is important. Well stated about the dxg 125 ( f/1.2) or example.

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In my program where people want still pictures at night in blackflash I simply turned on the array before powering on the camera. I would leave the array on in trail mode allowing the camera to snap a picture whenever it sensed movement and turned off the array after the camera turned off. In my opinion it takes the led a full second to reach maximum brightness using a constant current driver like the Buck Block. Battery consumption seemed no worse than running the camera in video mode. But even with the DXG125 most of the still pictures had motion blur if the critter moved any at all.

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