Can the flash of a camera have a negative effect on a CRT?

[Lawfer]

If you take a picture of a CRT screen like 5 centimeters/2 inches away from the screen, can it have nefarious effects? Like it damages the electron gun? Or the chassis? Or something else?

[SamIAm]

The electron guns and the chassis, I just can't imagine being in danger. The phosphors on the screen, however, are something I've been wondering about myself.

Now, a camera flash is so short-term, I'd still be very surprised if it could cause damage. The threat of camera flashes to paintings, for example, is known to be exaggerated. Direct sunlight, on the other hand, can really cook a CRT screen. Here is a quote I found on another forum:

Many years ago I sold major appliances for K-Mart. The manager was a firm believer in sidewalk sales, especially in the summer months. He instructed me to have our sign dept. create a number of 8" X 10" Sale signs and neatly tape them to the center of each console TV screen. After sitting in direct sunlight for the weekend each TV had a VERY disticnct rectangular dark spot pemanently displayed in the center of each CRT. It cost the store many $$$ to have all the picture tubes replaced (not a warranty problem):(

What I'd like to investigate is indoor lighting. Was the effect of the sunlight in the post above strictly thermal, or did certain wavelengths cause chemical breakdown, such as when UV light causes certain organic pigments to decay? Are any harmful wavelengths more prominent in particular types of lighting, such as fluorescent? Could keeping a desk lamp close to a CRT screen cause damage, or is the light intensity just not enough? Is there anything to be gained by covering the screen with something when it's not in use?

My money is on "probably not", but I've got a backup CRT stored high on a shelf close to a bright hanging light that I've covered with a thick cloth just for peace of mind.

[ChuChu Flamingo]

Here is what my research has pointed at.

CFL/Fluorescent bulbs do fade stuff, but it takes a lot longer than direct sunlight and even indirect sunlight. If you want proof just look at yellow baked Neo Geo MVS arcade marques that had fluorescent tubes lighting the marque or displays at walmart with brand new games sun faded.

Standard incandescent lights also seem fine, but the problem is in close proximity they give off heat which prematurely ages stuff. Definitely avoid Halogen bulbs as those give off a lot of heat and UV. Standard ones give off insignificant amounts of UV. Their UV spectrum is green and yellow.

LEDs seem like the best bet if you want to have light and keep your stuff looking good. Most LEDS have almost no UV and their spectrum of light is massively shorter than say fluorescent. A lot of museums have retro fitted their lighting fixtures for this very reason. I say if its good enough for museums its good enough for me.

Ultimately what sunfades stuff the most is ultraviolet rays as it fuels the decomposition of elements hence it fading. With this in mind all light contributes to fading to some degree.

Here is a pretty good article on it

https://www.nedcc.org/free-resources/pr ... ght-damage

[Xyga]

Direct sunlight, on the other hand, can really cook a CRT screen.

Thanks, you just had me remember that yesterday I've left one in a position where it would have remained exposed most of today's.
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Question for OP now; why use the flash anyway ?
Not that I have a lot of experience in taking pictures of CRTs lol, but the few times I did the camera flash definitely wasn't needed, rather the opposite as it would have quite obviously gotten in the way considering the highly reflective nature of glass. So I am genuinely not sure I understand why/what you're asking...

[Lawfer]

Question for OP now; why use the flash anyway ?

My camera won't let me take pictures without using the flash unless it detects that there is enough lighting, if not it will automatically use it.

[Xyga]

Ah ok, unless you can trick the sensor that'll be tough indeed. One thing could be taking only half crt / half a bright surface like a bright white wall behind.
But I don't know if you'll be satified with demi pictures. ^^