September 02, 2014, 05:29:41 AM

Author Topic: Can a (DSLR) flash cause permanent eye damage?  (Read 6856 times)

sandymandy

  • 6D
  • *****
  • Posts: 599
    • View Profile
Can a (DSLR) flash cause permanent eye damage?
« on: June 07, 2013, 03:46:45 AM »
Hi,

out of curiosity and since i just remembered as a kid i accidently fired off my compact camera flash directly in front of my eyes (  ::) ) im wondering if permanent eye damage is possible with my inbuilt 1100D camera flash for example. Some external flashes are able to burn plastic bags as can be seen on youtube. Oh and the compact camera flash just gave me purple vision for some time but nothing permanent.

Just wanna see some calculations of the mathematics/physics experts here (i suck at this) like

1.) Whats the minimum flash power needed to cause retinal burn or other permanent damage

2.) If its even possible to happen in real cuz light travels different inside the eyeball onto the retina than in the air i guess etc.

im just curious so please satisfy my scientific needs :)

canon rumors FORUM

Can a (DSLR) flash cause permanent eye damage?
« on: June 07, 2013, 03:46:45 AM »

bycostello

  • 1D Mark IV
  • ******
  • Posts: 910
    • View Profile
    • London Weddings
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #1 on: June 07, 2013, 04:30:29 AM »
yes.. but you'd have to be an idiot to get that close and powerful...

SwissBear

  • Rebel SL1
  • ***
  • Posts: 89
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #2 on: June 07, 2013, 05:13:03 AM »
a fully powered 580EX II can leave some patterns for about week or so on stressed eyes.

By stressed eyes i mean 3-5 days in row 1-2 hours exposure to direct sunlight in a snowy environment at midday at high elevation (no sane person would do this, we told all the kids is was mandatory to wear some eye protection during the midday ski break, but some would not listen).

Sometimes, communication between my 600D and the flash clogs up and it goes of at 1/1, thats how i "tested" it.

But then again, i guess that also a starting fluorescent tube would have caused trouble to these two kids.

But as the flash in the 1100D has less than a forth of the power of the 580EX II, you might get some patterns in your eyes that last for maybe some hours if you fire a 1/1 flash at close distance in pitch black environment.

For physical background: all i remember is that the amount of light is proportional to the square  of the distance to the light source. (double the distance results in 1/4 lightpower)
EOS 50D, 600D - 24-105L - 40f/2.8 - 85f/1.8 - 580ii - Lensbaby Muse, Composer with Plastic, Double Glass, Edge 80
Tokina 11-16f/2.8 - Sigma 150mm OS Macro
Flickr

Mt Spokane Photography

  • Canon EF 600mm f/4L IS II
  • ********
  • Posts: 8481
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #3 on: June 07, 2013, 09:58:59 AM »
The Press 25 bulbs that everyone used to use did not cause damage, and they gave off extremely bright for a far longer time than the 1/10,000 sec of a electronic flash.  I have a few dozen of them stashed away.  They keep getting more and more valuable every year.
 
 And then there were the Sylvania FF33 bulbs.
http://www.flashbulbs.com/CresImgs/PagePics/MegaFlsh/PF3300_350.gif

nvsravank

  • PowerShot G1 X II
  • ***
  • Posts: 50
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #4 on: June 07, 2013, 10:16:28 AM »
For newborns yes they can hurt. Try to minimize for newborns and babies. For adults you have to really try hard to damage, but it is possible. Kids are more susceptible. So not too many flashes on them.

unfocused

  • Canon EF 300mm f/2.8L IS II
  • *******
  • Posts: 2036
    • View Profile
    • Unfocused: A photo website
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #5 on: June 07, 2013, 11:16:38 AM »
If there were any risk of permanent eye damage the American trial lawyers would be all over this like white on rice.
pictures sharp. life not so much. www.unfocusedmg.com

AudioGlenn

  • 7D
  • *****
  • Posts: 351
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #6 on: June 07, 2013, 12:04:47 PM »
I too am curious about 3rd party batteries for my mk3.  I had 2 wasabi batteries for my T3i when I owned one and they worked well but I only had that camera for about 5 months before I sold it. 
5D mkIII  |  40 f/2.8 | 8-15 f/4L | 24-70 f/2.8L II | 70-200 f/2.8L IS II | 1.4x III TC | 600ex-rt | 430 ex ii | EOS M+22mm f/2 | EF to EF-M adapter

canon rumors FORUM

Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #6 on: June 07, 2013, 12:04:47 PM »

Skirball

  • 7D
  • *****
  • Posts: 341
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #7 on: June 07, 2013, 12:47:43 PM »
I'm confident that if you place the flash physically on the eye and fire it will cause permanent damage.  Caveat Emptor.

jdramirez

  • Canon EF 300mm f/2.8L IS II
  • *******
  • Posts: 2295
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #8 on: June 07, 2013, 01:37:53 PM »
 we need to get Adam and Jamie on this...  during sweeps weeks when all the gloves are off of what they are allowed to do.
Upgrade  path.->means the former was sold for the latter.

XS->60D->5d Mkiii:18-55->24-105L:75-300->55-250->70-300->70-200 f4L USM->70-200 f/2.8L USM->70-200 f/2.8L IS Mkii:50 f/1.8->50 f/1.4->100 f/2.8L->85mm f/1.8 USM->135L -> 8mm ->100L

GuyF

  • Canon 70D
  • ****
  • Posts: 317
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #9 on: June 07, 2013, 01:38:37 PM »
I recently saw a programme about Nobel prize winning physicist Richard Feynman who worked on the Manhattan project to build the first nuclear bomb. He said, "They gave out dark glasses that you could watch it with. Dark glasses! Twenty miles away, you couldn’t see a damn thing through dark glasses. So I figured the only thing that could really hurt your eyes (bright light can never hurt your eyes) is ultraviolet light. I got behind a truck windshield, because the ultraviolet can’t go through glass, so that would be safe, and so I could see the damn thing.

Time comes, and this tremendous flash out there is so bright that I duck, and I see this purple splotch on the floor of the truck. I said, “That’s not it. That’s an after-image.” So I look back up, and I see this white light changing into yellow and then into orange. Clouds form and disappear again – from the compression and expansion of the shock wave.

Finally, a big ball of orange, the center that was so bright, becomes a ball of orange that starts to rise and billow a little bit and get a little black around the edges, and then you see it’s a big ball of smoke with flashes on the inside, with the heat of the fire going outwards.

All this took about one minute. It was a series from bright to dark, and I had seen it. I am about the only guy who actually looked at the damn thing – the first Trinity test. Everybody else had dark glasses, and the people at six miles couldn’t see it because they were all told to lie on the floor. I’m probably the only guy who saw it with the human eye."

So there you go, as long as there's a sheet of glass between you and the light, you might be fine 8)

Mt Spokane Photography

  • Canon EF 600mm f/4L IS II
  • ********
  • Posts: 8481
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #10 on: June 07, 2013, 01:39:32 PM »
I'm confident that if you place the flash physically on the eye and fire it will cause permanent damage.  Caveat Emptor.

Actually, for certain types of eye exams, they do place a ring flash and camera on your eye to photograph the retina.  My Retina specialist does it every day with no issues.
 
If the light is strong enough and lasts long enough, as in a arc welder, your cornea will get burned.
 
Time of exposure, wavelength as well as brightness are factors.
http://doctor.ndtv.com/faq.aspx?fid=6852

Skirball

  • 7D
  • *****
  • Posts: 341
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #11 on: June 07, 2013, 01:46:28 PM »
I'm confident that if you place the flash physically on the eye and fire it will cause permanent damage.  Caveat Emptor.

Actually, for certain types of eye exams, they do place a ring flash and camera on your eye to photograph the retina.  My Retina specialist does it every day with no issues.


Obviously the level of brightness of the light will have an impact, but that's not what I was referring to.  Have you ever placed a speedlight on your skin and fired it?
« Last Edit: June 07, 2013, 01:48:27 PM by Skirball »

sunnyVan

  • Canon 70D
  • ****
  • Posts: 254
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #12 on: June 07, 2013, 02:08:10 PM »
A friend of mine is an eye MD. I'll see if I could remember to ask him when I see him.

I suspect damage is possible if a powerful flash is firing directly at the eyes and the eyes happen to focus on directly on the light source.

By the way, if you open the aperture all the way and point the camera directly at a bright sun, can it damage the sensor?
6D, 24-70 2.8L II, 16-35 F4L IS, 17-40L, 100 2.8L, 70-200L F4 IS, 85 1.8, 135L, Sigma 35 1.4, 600Ex-RT, Rokinon 14mm, EOS M

canon rumors FORUM

Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #12 on: June 07, 2013, 02:08:10 PM »

Skirball

  • 7D
  • *****
  • Posts: 341
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #13 on: June 07, 2013, 02:17:57 PM »
By the way, if you open the aperture all the way and point the camera directly at a bright sun, can it damage the sensor?

It's the same answer as the flash and the eye.

sunnyVan

  • Canon 70D
  • ****
  • Posts: 254
    • View Profile
Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #14 on: June 07, 2013, 02:55:35 PM »
By the way, if you open the aperture all the way and point the camera directly at a bright sun, can it damage the sensor?

It's the same answer as the flash and the eye.

 Kind of. But there's difference too. The eye can only regulate amount of light coming in by changing size of iris. Camera has iso, aperture, and shutter speed. To destroy the sensor I think you must be in manual mode and deliberately expose.

 When a flash fires at the eyes, they blink but not fast enough to keep out the immense amount of light. The iris contracts but probably not fast enough either.

Therefore I think it's much harder to mess up the sensor than the eyes by intense light. Just my two cents.
6D, 24-70 2.8L II, 16-35 F4L IS, 17-40L, 100 2.8L, 70-200L F4 IS, 85 1.8, 135L, Sigma 35 1.4, 600Ex-RT, Rokinon 14mm, EOS M

canon rumors FORUM

Re: Can a (DSLR) flash cause permanent eye damage?
« Reply #14 on: June 07, 2013, 02:55:35 PM »