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Old Jun 22, 2005, 10:29 AM   #11
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Buy a night vision scope, attach to camera

pianoplayer88key wrote:
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What do you do using a Canon S1 IS when you can't use the flash or get close to the subjects (and you don't want to alert them to the fact that you have a camera), and you're already at ISO 400 and F/3.1, and you want less image noise, AND the subjects are moving a lot (enough to blur at 1/40") but you can handhold at 1/8" at 380mm (I can), and you're shooting a moonlit scene at a distance of 50 feet and you don't have time to move closer?
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Old Jun 22, 2005, 2:46 PM   #12
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What is a good night vision scope that's inexpensive?

Or, Is there a good external infrared slave flash I could get, say, one that runs on 8 AA batteries and puts out about 250,000 watts of IR light for about 0.1 seconds? (except that I wouldn't be using the on-board flash, so how would it know when to fire unless I fire it manually? (maybe it could have a button that fits over my shutter on the camera.))

Or, a light that when constantly lit is putting out about 250 watts of IR? I'd guess with the same # of batteries it could probably run solidly for several minutes. Having it constantly lit would maybe not give me quite as much light, but would give me more room for error when I turn it on and activate the camera's shutter. (maybe if I learn how to use it properly I could crank the power up to something like 5,000 watts, turn it on, take the pic, and turn it off.)

Would something like that be powerful enough to get a good IR exposure at F/8.0, 1/1000", ISO 50, in total darkness, on a subject approx 250 feet away?
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Old Jun 22, 2005, 3:17 PM   #13
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Not to be a night vision snob, but I don't believe there is a "good", inexpensive night vision device. You can probably get "ok" images with a Gen 1 tube but they will be distorted and noisy, and the system will not produce a net amplification of light really. They are probably $150-$200 for an OK one.

Gen 2 is about $1k-1500 and has much better gain and less distortion but is more grainy.

Gen 3 produces really nice images (relatively) but is expensive... $2k-$3k.

I have some Gen 2 and 3 images on my website at http://www.talinia.net/img/nvd ... keep in mind a camera adapter wasn't used for any of those so the focus might not be perfect.

As for your question about an external infrared illuminator, that's an excellent idea, but it all depends on the infrared sensitivity of your camera. And uh, I don't think 8AAs contain 250KWh of power

What I would recommend doing is buying one of those cheesy 5,000,000 candlepower "Thor" lights or whatever for $50 and slapping an infrared filter on it. Depending on the quality of the filter your subject may see a dim red glow from it. The better the IR filter, the less the glow.

However, that still may not be enough... I really don't know. It all depends on your camera's IR hot filter.

On some Sony models you can enable Nightshot mode which flips that IR filter out of the way. I have not heard of this feature on any other brand of digital cameras.

Sonys with nightshot can produce very good, low-noise image with external illumination -- better than a night vision scope, and are significantly cheaper. Of course, that really doesn't help your current camera.

I guess it all comes down to how much quality you need and if you want to use external illumination or not.

You can always use the previously mentioned spotlight without the IR filter and get a nice color image, but whoever you're taking a picture of is going to be aware of the fact someone's pointing a very bright light at them.

pianoplayer88key wrote:
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What is a good night vision scope that's inexpensive?

Or, Is there a good external infrared slave flash I could get, say, one that runs on 8 AA batteries and puts out about 250,000 watts of IR light for about 0.1 seconds? (except that I wouldn't be using the on-board flash, so how would it know when to fire unless I fire it manually? (maybe it could have a button that fits over my shutter on the camera.))

Or, a light that when constantly lit is putting out about 250 watts of IR? I'd guess with the same # of batteries it could probably run solidly for several minutes. Having it constantly lit would maybe not give me quite as much light, but would give me more room for error when I turn it on and activate the camera's shutter. (maybe if I learn how to use it properly I could crank the power up to something like 5,000 watts, turn it on, take the pic, and turn it off.)

Would something like that be powerful enough to get a good IR exposure at F/8.0, 1/1000", ISO 50, in total darkness, on a subject approx 250 feet away?
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Old Jun 22, 2005, 4:04 PM   #14
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If I was going to spend that kind of four-digit money, I'd get a digital SLR that would fit in the small mini-pocket in my pants, has a 360,000mm zoom lens, (and here, I can't decide what aperture I want - I want something wide like F/0.125 to let in enough light, but narrow like F/128 to get good depth of field (everything from dust 0.1mm in front of the sensor to infinity to be in razor sharp focus)), has 0.000 uS power on to picture snapping shutter lag, several terapixels of resolution, standard deviation noise measurements of < 0.001, enough sensitivity to get a 1/60,000" shutter speed in near total darkness (something that would require an 8 hour shutter speed at F/1.4 and ISO 3200 to get a proper exposure), a movie mode such that worst, it'd make 1920i HDTV (or whatever the highest res is now) look like old 1970s computer / console graphics / text, enough memory for several days of constant movie shooting (and enough battery life for the same run time assuming constant zooming and focusing when in movie mode, and zooming and focusing and firing the flash, and with the LCD monitor constantly on for every still pic), and ability to preview with the multi-way foldable (when open it's something like at least 8" by 6", and 1200dpi resolution) LCD.

However, since nothing like that exists, is there ANYTHING out there? I know of visible light flashlights that are about $20 to $30 or so and run on 4 D cells, and up close they're maybe within about 8 stops of proper exposure, and a TV remote I think is reasonably priced (even though at 15" ISO 400 F/2.8 it's still a bit underexposed in close quarters).
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Old Jun 22, 2005, 4:58 PM   #15
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Heh... even Gen 3 night vision costs less than a "professional" SLR lens -- I don't think you'll get very far in SLR-land with the funds for a Gen 3 scope. If it makes you feel better, the units have been increasing in value lately due to the heavy demand from the Iraq war, so my scope is actually worth more than I paid for it.

But, night vision scopes do have limited photography applications.

The 4D flashlights give maybe 60 lumens of illumination, I'm really not sure if thats enough for 50 feet away using a fast 100-200 ISO exposure... but I doubt it.

My roommate's Sony F-717 using Nightshot took decent pictures in a dark room illuminated by a TV remote, but the IR diode there has no focus and not much throw to it, and is probably only about 1 lumen anyway.

You can buy a cheap flashlight -- the biggest and best are the "5,000,000 candlepower" Thor or Vectors, which are probably about 500 or 1000 lumens depending on which model you get and tend to have good throw. You can stick an IR filter on them if you reaaaallly need to.

I'm still not entirely clear what you're trying to photograph. Is being covert necessary?

The best pictures will always come when you illuminate the target with bright, white light.

pianoplayer88key wrote:
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If I was going to spend that kind of four-digit money, I'd get a digital SLR that would fit in the small mini-pocket in my pants, has a 360,000mm zoom lens, (and here, I can't decide what aperture I want - I want something wide like F/0.125 to let in enough light, but narrow like F/128 to get good depth of field (everything from dust 0.1mm in front of the sensor to infinity to be in razor sharp focus)), has 0.000 uS power on to picture snapping shutter lag, several terapixels of resolution, standard deviation noise measurements of < 0.001, enough sensitivity to get a 1/60,000" shutter speed in near total darkness (something that would require an 8 hour shutter speed at F/1.4 and ISO 3200 to get a proper exposure), a movie mode such that worst, it'd make 1920i HDTV (or whatever the highest res is now) look like old 1970s computer / console graphics / text, enough memory for several days of constant movie shooting (and enough battery life for the same run time assuming constant zooming and focusing when in movie mode, and zooming and focusing and firing the flash, and with the LCD monitor constantly on for every still pic), and ability to preview with the multi-way foldable (when open it's something like at least 8" by 6", and 1200dpi resolution) LCD.

However, since nothing like that exists, is there ANYTHING out there? I know of visible light flashlights that are about $20 to $30 or so and run on 4 D cells, and up close they're maybe within about 8 stops of proper exposure, and a TV remote I think is reasonably priced (even though at 15" ISO 400 F/2.8 it's still a bit underexposed in close quarters).
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Old Jun 22, 2005, 5:24 PM   #16
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It is very important that the subject not be able to see me, even when she's looking straight at me.

And, what's a good <$10 IR filter to get for my 4D Maglite? I could probably (for now, temporarily) limit myself to about 1/125" at 25 feet, F/3.1, and ISO 100.

And how much brighter would one of those lights you mentioned be, and would they be the same price? I don't mind if battery life is worse than my maglite so long as it's considerably brighter.

And, maybe 8 AA's don't contain 250 kilowatt-hours of power, but do they contain 250 kilowatt-seconds?

FYI, my camera can see a TV remote LED fairly brightly on the LCD. If I put the camera's lens right up to the remote's LED, set the ISO to 50 and aperture to F/2.8, and spot meter, I get approx a 1/60" to 1/100" shutter speed.

And, about getting a Sony camera, a while back I was looking for a good deal (< $40 or so including 512+MB memory stick and 2 good batteries) on a DSC-V1, but I gave up for now on that. Also, in addition to using it in the dark, I'd be using it in bright daylight, and you can't manually set the shutter speed, aperture, or ISO while in nightshot mode, resulting in extremely washed out (not just overexposed, probably mostly white) images.
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Old Jun 22, 2005, 5:52 PM   #17
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You can pick up Maglite IR filters on eBay for pretty cheap-- perhaps you should give one of those a try and see if your flashlight is bright enough?

If you don't want to spend any money at all, the ghetto IR filter of choice is some developed, but *NOT* exposed, film negatives. You will have to layer them.

If the Maglite is sufficiently bright and the filter isn't good enough, you'll need wratten (wrappen?) Hell, I can't remember anymore, it was something like that though, they were the best and run about $50-60 IIRC. From what I read they had a pretty tight wavelength tolerance range so your target should not be able to see any leaking visible red light. It's been so long since I read about it though my memory could be hazy.

Anyway, if that's enough illumination to make the shot work, you should be set.

If not, consider looking into one of those stupidly powerful spotlights or a Sony Nightshot camera/camcorder that is sensitive to IR.

A gen 1 night vision scope will also work but it will have poor image quality... then again, it will allow you to effectively bypass your camera's IR filter. I would rather buy a used Sony with Nightshot off eBay than a gen 1 scope though, gen 1 is pretty terrible.
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Old Jun 22, 2005, 6:02 PM   #18
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I must have been editing my post while you were replying.

How do I convert # of stops of increased brightness to # of lumens? Is 2 lumens 1 stop brighter than 1 lumen, 4 lumens 2 stops brighter, 8 lumens 3 stops brighter, 16 lumens 4 stops brighter (and so on), or is 2 lumens 1 stop brighter, 3 lumens 2 stops brighter, 4 lumens 3 stops brighter (than 1 lumen), or how does it work?


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Old Jun 22, 2005, 7:47 PM   #19
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Lumens aren't directly related to stops. A lumen is the measure of all the light emitted from a light source. It's a good way of comparing the outputs of flashlights.

A better unit for photography is lux, which is lumens per square meter. This tells you more about a light's throw or "hot spot".

I don't know any way of converting lux to stops, though. It should be possible in theroy given the distance, however, to solve.

To answer your question about a 4D Maglite vs. a spotlight, a 4D Maglite puts out about 60 lumens of light. That's not bad, but... one of the spotlights can do anywhere from 500-1000 lumens (1000 lumens is the output of both of your car's headlights on low). Actually that's exactly what the spotlights use... car headlight halogen bulbs hooked up to a 12V lead acid battery. Crude, bulky, yet very effective.

Lumens are a linear measurement so they're literally 10x brighter or so. Halogen bulbs are even less effecient than normal incandescants, so that means they'll have greater infrared output as well.

Anyway, not to bore you with geeky stuff.
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Old Jun 30, 2005, 2:00 AM   #20
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One other idea i had as far as IR photography...

get an IR filter for my S1 IS (I have the conversion lens adapter)
attach several 1-AA flashlights in a ring around the lens, each with an IR pass / VL block filter

Would that be a decent option for when portability is a must? I really need both hands to work the controls on the camera.
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