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Photo Forum / Digital Photography / Digital Photo / September 2005Technology to stop a digital camera from taking a picture
Hi all, I have put up an article on www.dimagemaker.com about some early research work being done to block digital cameras of taking a picture of something or someone that is to be protected. Food for thought. Cheers, Wayne Wayne J. Cosshall Publisher, The Digital ImageMaker, www.dimagemaker.com Assistant Director, International Digital Art Award Freelance writer and educator in graphic design, photography, digital technology Personal art site www.artinyourface.com wayne@dimagemaker.com Wear theodolight jewelry ? Might work if flash is used. Gene > Hi all, > [quoted text clipped - 15 lines] > Personal art site www.artinyourface.com > wayne@dimagemaker.com >Hi all, > [quoted text clipped - 3 lines] > >Food for thought. Quick, someone invent film! wayne <wayne@dimagemaker.com> spewed: > Hi all, > > I have put up an article on www.dimagemaker.com about some early > research work being done to block digital cameras of taking a > picture of something or someone that is to be protected. A direct link would be appreciated. Attempting to navigate that site hurts my weary eyes... blue, green, red, yellow, black, blinky ads... *squint*  SignatureVisit My Site: http://www.rubbertoe.com > wayne <wayne@dimagemaker.com> spewed: > > Hi all, [quoted text clipped - 5 lines] > A direct link would be appreciated. Attempting to navigate that site hurts > my weary eyes... blue, green, red, yellow, black, blinky ads... True, but the link took all of 2 seconds to find. Even so, it seems to me, this idea is easily subverted simply by putting the camera into manual mode and the correct use of shutter and aperture settings. Don't talk rubbish! The link took all of 2 seconds to find? Yeah, FO. > In article <Q8zYe.15877$ib1.6514@tornado.ohiordc.rr.com>, > > True, but the link took all of 2 seconds to find. Even so, it seems to > me, this idea is easily subverted simply by putting the camera into > manual mode and the correct use of shutter and aperture settings. > > wayne <wayne@dimagemaker.com> spewed: > > > Hi all, [quoted text clipped - 9 lines] > me, this idea is easily subverted simply by putting the camera into > manual mode and the correct use of shutter and aperture settings. No, if I remember the article, it used infrared to measure the reflection from the coating of the lens, and then turn on a strong light to overexpose anybody taking a picture. Obviously there the solution is to get cheap uncoated lenses :-) Or possibily a new lens coating that doesn't reflect the light bakc. SignatureMichael Meissner email: mrmnews@the-meissners.org http://www.the-meissners.org >No, if I remember the article, it used infrared to measure the reflection from >the coating of the lens, and then turn on a strong light to overexpose anybody >taking a picture. Obviously there the solution is to get cheap uncoated lenses >:-) Or possibily a new lens coating that doesn't reflect the light bakc. I don't think it has anything to do with lens coating; it depends on the camera behaving like a retroreflector, like the eyes of people or animals. If the shutter is open, and the aperture is reasonably wide, and the lens is focused at about the distance of the IR source, then the lens collects a fair bit of IR and focuses it on the film or CCD. Some of that light is scattered back towards the lens, which then collimates it back into a parallel beam and sends it back towards the source. This is called autocollimation, and it's a method used to determine whether a camera/lens pair is focusing properly at infinity. It's also how glass-beaded retroreflective road signs work. Adding an IR-absorbing filter would prevent this from working, since no IR would be returned. An IR-reflecting filter (hot mirror) would work just as well too, since the reflection wouldn't go back towards the IR source. But just keeping the shutter closed until exposure time is just as good. Dave Wayne For someone with such artistic talent (www.artinyourface.com), your website is terrible! > Hi all, > [quoted text clipped - 15 lines] > Personal art site www.artinyourface.com > wayne@dimagemaker.com Robert and Tom, The site was put up 3 months ago. I've been concentrating on content but a redesign is in the works. Cheers, Wayne Wayne J. Cosshall Publisher, The Digital ImageMaker, www.dimagemaker.com Assistant Director, International Digital Art Award Freelance writer and educator in graphic design, photography, digital technology Personal art site www.artinyourface.com wayne@dimagemaker.com > I have put up an article on www.dimagemaker.com about some early > research work being done to block digital cameras of taking a picture > of something or someone that is to be protected. > > Food for thought. Indeed. I'm hoping it's technically unfeasible; that seems fairly likely. Otherwise we need to resort to making it illegal, much as I dislike the invocation of state power. SignatureDavid Dyer-Bennet, <mailto:dd-b@dd-b.net>, <http://www.dd-b.net/dd-b/> RKBA: <http://noguns-nomoney.com/> <http://www.dd-b.net/carry/> Pics: <http://dd-b.lighthunters.net/> <http://www.dd-b.net/dd-b/SnapshotAlbum/> Dragaera/Steven Brust: <http://dragaera.info/> > > I have put up an article on www.dimagemaker.com about some early > > research work being done to block digital cameras of taking a picture [quoted text clipped - 5 lines] > likely. Otherwise we need to resort to making it illegal, much as I > dislike the invocation of state power. Geez! What're you people doing, taking stupid pills? Here's a tip: Its not feasible and even if it is, its easily side-stepped simply by placing a camera into manual mode or using a powerful telephoto or zoom lens. Actually I am not sure. Yes, going manual could help with the current system but I can conceive of ways to overload the actual CCD. The long telephoto or zoom lens also may not be an answer. I learnt a long time ago that when it comes to engineering, if someone says it can't be done, they are usually wrong. The right question is whether it can be done in a cost effective (whatever that means) and readily deployable manner that can cope with real world variance. The reality is that after posting the article I sat down and worked out a number of other possible approaches that could readily be used to shutdown a digital camera by attacking the electronics. Not hard if you don't mind the risk of frying the odd camera or two. Cheers, Wayne Wayne J. Cosshall Publisher, The Digital ImageMaker, www.dimagemaker.com Assistant Director, International Digital Art Award Freelance writer and educator in graphic design, photography, digital technology Personal art site www.artinyourface.com wayne@dimagemaker.com >Actually I am not sure. Yes, going manual could help with the current >system but I can conceive of ways to overload the actual CCD. The long >telephoto or zoom lens also may not be an answer. No, it's a turkey. As the article itself points out, it won't work with cameras where the CCD is covered before exposure. That means all DSLRs, and that's what professional paparazzi are going to be using. But there are P&S cameras that will close their mechanical shutter simply by turning off the LCD display and using the optical viewfinder instead. In addition, it seems like the system is going to be triggered by retroreflective safety strips or paint used in some clothing, since they will return a stronger reflection than the camera. I have one Tshirt that does this, my backpack has a strip of it, and some jackets and even shoes use these reflectors. In addition, human and animal eyes act as retroreflectors. If the system isn't sensitive to them, it's also not going to detect some of the small P&S cameras that have smaller apertures and reflect even less light back than a human eye. So any such system is going to have lots of false alarms, triggering the "light projector" to "blast" the nearby spectators needlessly. I predict the system would be so annoying that it would quickly get turned off. >The >reality is that after posting the article I sat down and worked out a >number of other possible approaches that could readily be used to >shutdown a digital camera by attacking the electronics. Not hard if you >don't mind the risk of frying the odd camera or two. If it can affect a digital camera at a distance, it can also affect or damage cellphones, PDAs, computers, hearing aids etc. Depending on strength, it might affect pacemakers. You're suggesting this could be set up in a public place and left to fire automatically whenever it detects a camera? Dave Dave, I can certainly think of places where a government would be willing to do that. Can't you or am I just more cynical about governments? Cheers, Wayne Wayne J. Cosshall Publisher, The Digital ImageMaker, www.dimagemaker.com Assistant Director, International Digital Art Award Freelance writer and educator in graphic design, photography, digital technology Personal art site www.artinyourface.com wayne@dimagemaker.com >I can certainly think of places where a government would be willing to >do that. Can't you or am I just more cynical about governments? I can think of areas where governments would like to know about *all* of the electronics you are carrying, and whether it can transmit or record audio or video. It seems to me that the best way to protect such areas is to search people entering them, not to use devices that indiscriminately disrupt most electronic devices. But this particular gadget was proposed as a way of protecting people who don't want to be photographed in public. For that purpose, I think both it and your inventions are not practical. Dave > Actually I am not sure. Physical reality doesn't care whether or not you are "sure". > Yes, going manual could help with the current > system but I can conceive of ways to overload the actual CCD. The long > telephoto or zoom lens also may not be an answer. The inverse-square-law will have a word with you. > I learnt a long time ago that when it comes to engineering, if someone > says it can't be done, they are usually wrong. They were wrong because their statements were not backed up by empirical evidence/theory. Are yours? > The right question is > whether it can be done in a cost effective (whatever that means) and > readily deployable manner that can cope with real world variance. And the answer is, right now, "almost certainly not". > The > reality is that after posting the article I sat down and worked out a > number of other possible approaches that could readily be used to > shutdown a digital camera by attacking the electronics. Not hard if you > don't mind the risk of frying the odd camera or two. The fact of the matter is that the counter-measures are trivial and inexpensive, while the other end of the problem is difficult and likely to be very expensive (both in terms of cost and power requirements). You tell us: who is going to lay out alot of money for a system that can be easily defeated? (Excepting the USG who is still doling out billions on 'star wars' ineffectiveness). Who would even bother trying to build as much without a _solid_ theory, and corresponding analysis? Personally, it would be alot cheaper, and vastly more effective, to just wand people with NLJD's (see http://en.wikipedia.org/wiki/TSCM) at the door and kick in the teeth of anyone who trips them. But hey, knock yourself out if you want... Why the aggression in your replies? Inverse square law does not apply to this. If you are close enough that the inverse square law has not dimmed the light reflected by the subject so much that you can't get a pic then it will also not have dimmed any countermeasure. Actually to my comment about engineering I was referring to your reply. You seem very definite, so to mirror your statement, can you back your statements up? Since your inverse square reference shows a lack of understanding, I suspect the issue my be with your reasoning. No, I agree, probably not possible right now. But that can change real fast. As to who would use, I actually never thought it would appeal to many beyond government. Cheers, Wayne Wayne J. Cosshall Publisher, The Digital ImageMaker, www.dimagemaker.com Assistant Director, International Digital Art Award Freelance writer and educator in graphic design, photography, digital technology Personal art site www.artinyourface.com wayne@dimagemaker.com >Inverse square law does not apply to this. If you are close enough that >the inverse square law has not dimmed the light reflected by the >subject so much that you can't get a pic then it will also not have >dimmed any countermeasure. Sure it applies. The detection system is vulnerable to the inverse square law - the amount of light returned by the camera to the detection system is reduced to 1/4 if you double the distance to the camera. So the system won't work beyond some particular range for a given camera. If you're using a point&shoot camera, this may place you beyond flash range (inverse square again) but shooting by ambient light is still possible. And if you're professional paparazzi, you'll just bring a larger flash and/or increase ISO so you can shoot from further away. Dave >>Inverse square law does not apply to this. If you are close enough that >>the inverse square law has not dimmed the light reflected by the [quoted text clipped - 13 lines] > > Dave ...or a telescope if my subject is on a different mountain. Signaturejer email reply - I am not a 'ten' Dave, Sorry, but you don't seem to get what I mean. Yes, the inverse square law applies, of course. But it applies to everything. So if you are going to get enough light to make an exposure, then the countermeasure can also put out enough light to upset the exposure system. The area most vulnerable is the IR detection system, but I think the real issue is actually the field of view issue with longer lenses. And of course if you are using an SLR then the issue goes away except for a very small time window when the mirror pops up and the shutter opens. Also, if I remember my optics correctly, the inverse square law applies to point sources. For area light sources, ie light reflecting off of real objects the relationship is a bit different. I've never noticed a 2 stop extra exposure if I halved the distance to a real subject. Cheers, Wayne Wayne J. Cosshall Publisher, The Digital ImageMaker, www.dimagemaker.com Assistant Director, International Digital Art Award Freelance writer and educator in graphic design, photography, digital technology Personal art site www.artinyourface.com wayne@dimagemaker.com > >Inverse square law does not apply to this. If you are close enough that > >the inverse square law has not dimmed the light reflected by the [quoted text clipped - 13 lines] > > Dave >Sorry, but you don't seem to get what I mean. Yes, the inverse square >law applies, of course. But it applies to everything. So if you are >going to get enough light to make an exposure, then the countermeasure >can also put out enough light to upset the exposure system. Sure, but that's not what *I* meant, nor the person you were originally replying too. The inverse square law matters in determining whether the IR detection system can detect the camera. If the system cannot detect the camera, it does not trigger, and the photograph is taken without interference. It simply doesn't matter whether the countermeasure system *could have* put out enough light if it had triggered, since it did not. >Also, if I remember my optics correctly, the inverse square law applies >to point sources. For area light sources, ie light reflecting off of >real objects the relationship is a bit different. I've never noticed a >2 stop extra exposure if I halved the distance to a real subject. It certainly does apply to light from the subject, but it doesn't change the exposure. If you halve the distance to a real subject, the lens does capture 4 times as much light from each point on that subject. But the image also occupies 4 times as much area on the image plane, so the intensity per unit area remains the same, and that's what determines the exposure you need. Dave in genera, if you can lock it, you can unlock it. There is no such a thing as unbreakable lock or code. Someone will find a way around it. to stop cameras from firing, they would have to be fitted with some sort or receiver. Currently, none has it. mirrors, lasers etc - can do much harm, there is always a pola filter, there are skilled retouchers to correct an image. but you can increase a distance or put extra few feet of a fence. May help, may not. >>>I have put up an article on www.dimagemaker.com about some early >>>research work being done to block digital cameras of taking a picture [quoted text clipped - 11 lines] > side-stepped simply by placing a camera into manual mode or using a > powerful telephoto or zoom lens. I think the only way this would work is for a mandate for all digital cameras to have a special radio or IR sensor built in, and for protected targets to have the appropriate signal to disable cameras aimed at it. Obviously that would (a) raise free speech issues, and (b) create a cottage industry of technologies to circumvent it. > > > I have put up an article on www.dimagemaker.com about some early > > > research work being done to block digital cameras of taking a picture [quoted text clipped - 7 lines] > > Geez! What're you people doing, taking stupid pills? Why pick on me? I *said* I thought it was "fairly likely" that it was "technically unfeasible". SignatureDavid Dyer-Bennet, <mailto:dd-b@dd-b.net>, <http://www.dd-b.net/dd-b/> RKBA: <http://noguns-nomoney.com/> <http://www.dd-b.net/carry/> Pics: <http://dd-b.lighthunters.net/> <http://www.dd-b.net/dd-b/SnapshotAlbum/> Dragaera/Steven Brust: <http://dragaera.info/> just finished the article. Locks are to keep HONEST people away. such stupid idea, sorry for harsh word. it is not going to work, I can already use something to beat it. But I will not tell you, not to make your life easier. If you want to keep something away from prying eyes, do just that. Hide it. If it is on a public display, you will not be able to control it. A knowledgeable person will find a counter-method. Quicker than you think. Show me one piece of software that would not be cracked by youngster cracker? All the schemes from microsoft, adobe, symantec,autodesk..... Some museums, (Vienna)use difficult illumination and ban you from taking photographs. Yet I managed to do, what I wanted, without a flash (with digital camera). >Hi all, > [quoted text clipped - 15 lines] >Personal art site www.artinyourface.com >wayne@dimagemaker.com Wouldn't something like this be effective? http://www.glock.com/g17.htm >> Hi all, >> [quoted text clipped - 19 lines] > > http://www.glock.com/g17.htm Yes, but that means all cameras suddenly become downgraded to "single use" units... :) >Hi all, > [quoted text clipped - 15 lines] >Personal art site www.artinyourface.com >wayne@dimagemaker.com 1> Why detect, why not just protect? In other words any such system that needs to 1st detect a digital camera "before" it activates a counter measure(s) would be next to useless. 2> Blanket the area with something that virtually all cameras can "see/record" by "humans can't. UV & Near IR comes to mind & powerful enough laser(s) fired into a high speed rotating mirror might blanket an area with enough energy to impend/impair a quality digital image from being recorded, especially @ night. This could probably be done without much if any concern to harming human eyesight. Then again if a government or corporation was that concerned about privacy, I wonder just how concerned they might be as to possible long exposure to there countermeasures? 3> If such concerns for human eyesight or health wee not much of a concern, there are many much more effective countermeasures that could be used. 4> Here's a scary thought. How about requiring the manufacture's of digital cameras to incorporate some type of RF ID tag system that not only transmit's it's unique code to ID the likely user/owner but also to shut down the camera for x amount of time? Just hypothetical ideas/questions? Respectfully, DHB "To announce that there must be no criticism of the President, or that we are to stand by the President, right or wrong, is not only unpatriotic and servile, but is morally treasonable to the American public."--Theodore Roosevelt, May 7, 1918 yoda2k@verizon.net writes: >2> Blanket the area with something that virtually all cameras can >"see/record" by "humans can't. UV & Near IR comes to mind & powerful >enough laser(s) fired into a high speed rotating mirror might blanket >an area with enough energy to impend/impair a quality digital image >from being recorded, especially @ night. A digital camera's spectral response is easily restricted to visible light with the appropriate filter. Casual photographers won't have one, but professional paparazzi will once they encounter this system. Dave > Hi all, > [quoted text clipped - 3 lines] > > Food for thought. The technology already exits: mass media and cops with guns. Jeff > > Hi all, > > [quoted text clipped - 5 lines] > > The technology already exits: mass media and cops with guns. The Thunderbirds organization has had an automatic camera detector since the 60s so I'm sure others have developed similar technology |
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