Luminous Landscape Forum
Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: orc73 on October 05, 2014, 01:52:27 am
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Hi
I'm getting electricity from the camera body, fingers and feed burning.
I experienced it on two shootings. In both I was at a higher point in the studio to shoot from above.
I was very strong yesterday, almost had to drop the camera. I could not have been shooting this way. The assistant was so friendly to give me his rubber flip flops, which solved the problem(if I wouldn't touch something else with my body).
First time was on a macbook pro 2012, yesterday on a new imac from the studio I shot. Both with the original firewire cable and with the firewire to thunderbold adapter(yesterday I used the studios adapter).
This happened also with the iphone connected to usb, which I connected to the studios imac yesterday.
best regards
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Were you using a sync lead direct to flash pack? If so try a radio trigger?
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no it was with Pocketwizards once, the other time with Elinchrom Trigger
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You are telling us that two devices (camera and phone) connected to the mac computer gave you shocks. You are also telling us that it happened with two different mac computers. Therefore, the only thing that is common between these incidents is the plug the computers were connected to.
It seems that your house wiring should be checked.
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That situation could arise if the devices are connected to different outlets.
Best regards
Erik
You are telling us that two devices (camera and phone) connected to the mac computer gave you shocks. You are also telling us that it happened with two different mac computers. Therefore, the only thing that is common between these incidents is the plug the computers were connected to.
It seems that your house wiring should be checked.
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I'd suspect the power outlets. In the best case it's just bad grounding of the camera or Mac, or a lack of grounding on the outlet, and you're getting some leakage. This is a nuisance but not really dangerous. In the worst case it's a bad ground in the whole studio, and if there were a short circuit of a power phase to ground elsewhere in the studio you can be set up for a dangerous ground loop with all the "grounded" metal casings of your equipment going hard-live. I'm probably talking out of my ass, but I suspect this scenario could kill you. Reality is probably somewhere between these extremes.
Of course, I'm just making this up as I type, someone who knows about power engineering will probably have a smarter opinion.
Edmund
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It actually was is in two different studios.
Not really concerned it would kill me, though try to shoot with a camera that is "burning" in your hands.
If it is grounding issue, how can I solve it? And funny if i stayed on same hight level as the computers, its not an issue. Only if I go up. And I had to go up.
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It actually was is in two different studios.
Then exchange the cable connecting the computer to the power outlet and any adapter you normally use with your computer and brought with you in the other studio. If this does not solve your problem, have your computer checked.
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It actually was is in two different studios.
Not really concerned it would kill me, though try to shoot with a camera that is "burning" in your hands.
If it is grounding issue, how can I solve it? And funny if i stayed on same hight level as the computers, its not an issue. Only if I go up. And I had to go up.
Electromagnetic induction affecting whatever you were standing on? Why don't you get a voltmeter and probe for differences between camera case voltage and the voltage of whatever you're standing on? I'm assuming its a conductor or the flipflops wouldn't have made a difference. The different studios issue is confounding, by measuring electrical potential differnces with a voltmeter should help you track it down. Keep in mind that the voltage could be ac, dc, or both.
Jim
Jim
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There isn't enough voltage in the tethering cable from the computer to cause a shock normally. Also odd is that the problem occurred only when you went up. Was your ladder leaning on any conduit or wires or touching any walls? I assume that since the flip flops help you, that the ladder or support you went on is metal and part of the electrical path that is problematic.
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It was a stair in both locations, and yes they have metal.
I dont need a volt meter, i can feel it burning. It happens in different locations, different computers, different computer cables, different thunderbolt adapter,same camera, same firewire cable.
I assume only identical parts can responsible, camera probably being the one as the one.
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Neither the firewire cable nor the Hasselblad could carry voltage over 12V if the computer /mains supply were working properly. Therefore, the computer or mains supply are not working properly. The voltage must come from somewhere. The camera battery is certainly not delivering 110V. The firewire specs do not see that this interface should deliver 110V. So where is the 110V coming from, uh?
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Neither the firewire cable nor the Hasselblad could carry voltage over 12V if the computer /mains supply were working properly. Therefore, the computer or mains supply are not working properly. The voltage must come from somewhere. The camera battery is certainly not delivering 110V. The firewire specs do not see that this interface should deliver 110V. So where is the 110V coming from, uh?
Right, except he doesn't know whether it's 110v or not. He doesn't even know if it's ac or not.
Jim
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I've seen buildings where the hot and return lines were reversed at the circuit breaker box. This can cause things that are normally grounded to have a potential. Reversed wiring is easily tested for with one of the plug in testers sold at hardware stores.
When I went to UC Berkeley, my cheap landlord got tired of having blown fuses in the building and instead of upgrading the old electrical wiring and service from the pathetic 60amps (for 4 units) he replaced the fuses with short sections of copper pipe. This worked for about a year until the copper got oxidized. After that the pipe would thermal cycle with load and change dimension and have varied resistance. I could watch the lights dim and get bright. One day some of my appliances and light bulbs burnt out. I put in a voltmeter to the wall and saw that the voltage which is normally about 117VAC was ranging between 80VAC and 180VAC. That's when I discovered the pipe in the fuse box. The return or neutral side pipe had collapsed and lost contact and therefore there was no path for the electricity in the building wires to ground. Some appliances were 220 v which brought both hot legs together and this is what made up the over voltage. Very dangerous situation. PG&E red tagged the building and he had to fix everything and pay all the renters for the burnt out appliances. These days most transformers are world ready meaning they can accommodate the range of 110-220 but then in the 90's only a few were.
Anyhow for the OP, I'd check the building mains… I can't imagine getting a shock from the camera or notebook as neither has enough voltage to give you a shock.
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Right, except he doesn't know whether it's 110v or not. He doesn't even know if it's ac or not
If one feels a shock, it is more than the 12V than the thunderbolt to firewire adapter delivers.
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I'm not at a power plant.my home and most of the studios.
Does it matter? my camera is connected to the computer, not in the power plug.
And of course it is not the hasselblad battery, as written above it only happens tethered, it only happens when I move up 2-3meters, not always, sometimes stronger, sometimes less.
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When I went to UC Berkeley, my cheap landlord got tired of having blown fuses in the building and instead of upgrading the old electrical wiring and service from the pathetic 60amps (for 4 units) he replaced the fuses with short sections of copper pipe. This worked for about a year until the copper got oxidized. After that the pipe would thermal cycle with load and change dimension and have varied resistance. I could watch the lights dim and get bright. One day some of my appliances and light bulbs burnt out. I put in a voltmeter to the wall and saw that the voltage which is normally about 117VAC was ranging between 80VAC and 180VAC. That's when I discovered the pipe in the fuse box. The return or neutral side pipe had collapsed and lost contact and therefore there was no path for the electricity in the building wires to ground. Some appliances were 220 v which brought both hot legs together and this is what made up the over voltage. Very dangerous situation. PG&E red tagged the building and he had to fix everything and pay all the renters for the burnt out appliances. These days most transformers are world ready meaning they can accommodate the range of 110-220 but then in the 90's only a few were.
What you are describing would only be possible in countries using the same power distribution systems as the USA. In France, for example, you would not be able to dispense with neutral (using the ground for return), it would immediately trip the main switch. Also: reverse-phase 220V power only exists in some 110V countries, like the USA. In Europe, mostly, we only have single phase 220V and tri-phase power supply (the later being only common in some countries like Germany).
Why am I writing this? I don't intend to make a discourse about power distribution on a photo forum, obviously. I just want to point out that we do not know where orc73 lives, so we should not assume he is using the power distribution system we are used to.
This being said: if the camera is hot, there is either something wrong with the computer or with the mains power. It simply cannot happen via a firewire connection that conforms to specs.
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well how do you define shock, definitely it's burning strong enough that I can not hold the camera. It's not that my hair goes up.
I don't know how 12v feel.
I only know how electric fence feels for the sheeps :) and that is a pulsating power fed by a car battery.
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I don't know how 12v feel.
You would not feel anything with 12V.
I only know how electric fence feels for the sheeps :) and that is a pulsating power fed by a car battery.
There is a device between that car battery and the fence that makes sure the fence is energised with considerably more than 12V so that the sheep feels the fence.
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I'm on a job in Thailand actualy. 220v. the buildings are of different age.
As far as I know between the laptop and the power plug, the apple charger has a transformer. So I don't understand why it matters.
But then I'm a photographer and not and a power pro. :)
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What happens when you unplug the laptop from the mains power?
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I'm on a job in Thailand actualy. 220v. the buildings are of different age.
As far as I know between the laptop and the power plug, the apple charger has a transformer.
Your Apple charger has tiny prints on it. Somewhere it says "Input" and then some. If it says "Input 100-240V" (like mine), you don't need a transformer.
What happens when you unplug the laptop from the mains power?
That is a good question. Additional question: do you have anything connected to the computer and to the mains as well (e.g. an external drive)?
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Yes I was thinking about unplugging the laptop to try what happens, that will not be a solution for the imac or computers in commercial studios.
Attached to my macbook is usually a wacom. Attached to that imac was usb drive.
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Attached to my macbook is usually a wacom. Attached to that imac was usb drive.
The Wacom digitiser is not connected to the mains (unless it is the one with a display...), so it does not count. The USB drive will only count if it has its own power supply, connected to the mains.
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You have to understand that the feeling/sensation the OP is mentioning is from higher voltage AC. This is distinctly different from the low-voltage DC that is in the cabling of your devices. It is possible there is a ground loop from plugging into different outlets with a different ground potential.The only time I had ever been shocked when using your camera was when the polarity of the sync cord was backwards and the high-voltage AC in the trigger was bleeding through
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I understand that the OP has a problem, and at this point he seems to be lining up for a Darwin award (http://www.darwinawards.com/darwin/).
"Photographer in Thailand complained about getting shocks from his camera and fetched rubber shoes which made shocks disappear. Then to take perspective shots, he placed metal step ladder on metal drain, and held camera in one hand while grasping ladder rungs in the other. Ambulance arrived late and were incapable of reanimating."
I may not be much of a photographer but I do know something about electricity. I strongly urge the OP to stop posting and go seek professional assistance.
BTW what usually kills people AFAIK is the fact that they suffocate because their lung nerve input has been overloaded by the 50Hz AC frequency. It doesn't take much of a current to do this.
Edmund
You have to understand that the feeling/sensation the OP is mentioning is from higher voltage AC. This is distinctly different from the low-voltage DC that is in the cabling of your devices. It is possible there is a ground loop from plugging into different outlets with a different ground potential.The only time I had ever been shocked when using your camera was when the polarity of the sync cord was backwards and the high-voltage AC in the trigger was bleeding through
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ok I might be a photographer and I made be stupid.
So if you are so much cleverer I'm sure you are able to give advice in a way so also the most stupid guys understand, right?
And that's why we have forums, because some guys know things or have experience about things, other guys don't have.
It's never a shame to ask questions, it is a shame not to ask and do stupid things.
To keep in the topic, it seems there are problems with electricity in Thailand in general as I found out. Grounding problems usualy.
Now calling a professional will not help. He will know as much about electricity as your grandmom, and just lucky enough, never got hit to strong so he can still work in this job. Besides they will not change the cabling in the house, because some foreigner has an electricity problem.
What can I do?
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What can I do?
Track it down. But you've already rejected my suggestion to start probing around with a voltmeter, saying you don't need it because you can feel the shock.
I dont need a volt meter, i can feel it burning.
There's an electrical potential developing. You need to find out what parts of your studio are at the same potential, and what parts are at different ones. Make a map. I bet you'll find a clue there. However, you can't do that without a voltmeter, and you say you don't need one to solve your problem. So I'm out of ideas.
One thing you might do to help us troubleshoot the problem is post some pictures of the studio and setup.
One thing you might do to help yourself solve the problem is run a wire from the ground of the outlet the sompute is plugged into to where you're taking the picture and touch the ground and see if you get a shock. Let me be clear that I think this is dangerous and inexact, and that I recommend the -- now rejected -- voltmeter.
Jim
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@Edmund: besides even obviously get fed intelligence on the baguette you don't need to talk to the other forum member about the OP and make jokes. As you can see the OP can read himselves a bit too. so you can adress directly with your constructive suggestions.
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thanks Jim for your concrete formulations, you might be right about the voltmeter, I just will not be able to interprete the results.
As for the plan I don't really have much to plan, there is a plug in the wall, a cable to the computer, and a firewire to the camera.
For dummies:
As far as I can follow you, in this plan, the problem must be in the wall. to be precise in most walls of thailand.
Even if I could get it fixed in my home, I will have the problem in every location.
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thanks Jim for your concrete formulations, you might be right about the voltmeter, I just will not be able to interprete the results.
Show us pictures of the studio with circles and arrows and explanations. Show us the outlet the computer is plugged into. Show us where you're standing. We'll suggest places to do measurements. Tell us what they turn out to be. Maybe we can do this by remote control. Is there no one available who knows anything about electricity?
Jim
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I certainly won't get any circuit plans.here is one location, the 2nd one looks similar. except the macbook is replaced with an imac.
I forgot to draw the hdmi cable to the monitor.
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I certainly won't get any circuit plans.here is one location, the 2nd one looks similar. except the macbook is replaced with an imac.
I forgot to draw the hdmi cable to the monitor.
Good diagram. How about some photos?
Jim
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I am not going to tell you to setup experiments with wires between your equipment and anything else because my feeling is that such experiments could kill you and I don't think that would be funny.
There are always competent guys at electric utilities and larger installations like big hotels - something like a $20 bill should cover an hour's work for a guy and his tools, over in Thailand.
Edmund
@Edmund: besides even obviously get fed intelligence on the baguette you don't need to talk to the other forum member about the OP and make jokes. As you can see the OP can read himselves a bit too. so you can adress directly with your constructive suggestions.
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Thanks Edmund, I'm also not able to classify if the danger of the situation.
an answer like "Dude your life is in danger, don't tether in that country anymore" would be discouraging but clear :)
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Orc73,
I'm sorry for any inappropriate language. I think your life may be in danger. The only way you can tether safely is with no external screen ( HDMI wire unplugged) and with the computer and camera running off battery power, all power adapters completely unplugged from camera and computer.
:)
Edmund
PS. There are intuitive guys and systematic guys. I can do the systematic calculation stuff, but basically I'm mostly intuitive. There is something about your story and the installation diagram which I simply don't like.
Thanks Edmund, I'm also not able to classify if the danger of the situation.
an answer like "Dude your life is in danger, don't tether in that country anymore" would be discouraging but clear :)
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I certainly won't get any circuit plans.here is one location, the 2nd one looks similar. except the macbook is replaced with an imac.
I forgot to draw the hdmi cable to the monitor.
From this plan, I strongly suspect the Dell screen. I may be wrong, of course.
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From this plan, I strongly suspect the Dell screen. I may be wrong, of course.
The guys in aviation call this the swiss cheese - normally nothing can fall through, but if the holes suddenly line up - bang!
Yes, one path for the leakage might be via the HDMI from the Dell screen - that's one hole -, but of course there should be no real path to anything live on that HDMI cable so something would need to be wrong on the Dell side -second hole- which may mean that the screen has a fault or the ground of the Dell is already live, which it may already be because it is live at the outlet etc etc.
I don't like this whole setup. Sorry. One more hole that lines up and there may be a real life-threatening issue. Which is why I am clearly telling Orc 73: "Dude, please stay away from this".
Edmund
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Sounds like the charger is faulty and leaking earth to active, (or you are using a faulty extension cord).
Is it non genuine, (meaning it wasn't new with the computer as non genuine ones can still be marked Apple)?
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Ok after some research basically there is electricity "leaking" everywhere in this country and nobody want's to do shit about it.
Be aware of that if you ever travel here.
Anyway it is not camera related then. Thanks for everybody who was trying to help!
Even when working on the computer, as soon I touch the metal ladder next to me that goes up, it will transfer. In Fact the USB Wacom having the worst effect(even when the laptop is not connected to the charger), the dell also has strong effect, unplugging everything reduces the problem.
I could never have imagined, the wacom tablet could have this influence. Especially I can't imagine where the power comes from then, as the laptop battery is the only source in this case. Or the ladder gets it somewhere.
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Probably someone screwed the ladder into the wall and one of the screws hit a wire inside the wall or if the building wires are in metal conduit pipes, sometimes they get pulled or bent and the wires can come into contact with the metal pipes - especially at junction boxes where the insulation has been taken off for connection to switches etc. I've seen a lot of that kind of stuff in industrial spaces where fork lifts and shelving are present for example.
That's just a guess but perhaps its a good idea for you to keep your shoes until you find out the source of the power - maybe even wear rubber boots and gloves?
You can track the source down by starting to eliminate things one at a time - pull the laptop charger off the computer, use a different monitor, different tether cable, or switch off one fuse at a time in the buildings electrical breaker box. When the shocks stop, you know at least what part it was coming from.