View Full Version : Solar Eclipse = CMOS Damage?
Craig Kovatch May 19th, 2012, 04:23 PM Hello.
There's a solar eclipse tommorrow and I'd like to get some timelapse footage with an EX-1R, but I'm worried about damage to the sensors. Is there anything I should be aware of? Is this even a good idea?
Thanks.
Craig
Cliff Totten May 19th, 2012, 05:39 PM I wouldn't try it with an EX.
I did burn out a CCD sensor on a point and shoot camera while shooting a "Solar Halo" in Miami. Got 5 or 6 awesome pix but then started getting thick red lines shooting vertically up the sensor that end in a colored "dot". This was several years back. I had to throw that little camera away.
I would try it with an old camera that I didn't care about but never my EX1R.
CT
Bill Koehler May 19th, 2012, 06:47 PM I would be very cautious about this. Considering it is common advice to use some kind of heavy filter for viewing with your eyes, it's easy for me to believe there is a real risk of damage to any kind of camera. At the very least, crank that aperture down as small as possible, crank the ND filter all the way up, add a lot more, and then consider backing off as needed, assuming you have enough filtration.
For more authoritative info, read this all the way through. It should give a good starting point.
How to Safely Photograph the Sun (A Photo Guide) | Solar Eclipses | Space.com (http://www.space.com/15733-solar-eclipse-safe-photography-tips.html)
Robert Turchick May 19th, 2012, 07:42 PM I read everything I could find on safely photographing and videoing the eclipse and decided the risk is too great. Had I been a little quicker in finding out about the eclipse I could have bought the proper filters. I don't think the standard ND filters on the video cameras are strong enough and several sites stated the variable ND filters which rely on polarizing filters still let a significant amount of UV and other potentially damaging rays through.
I have to second Bill's thought that the experts say a welders mask is good protection for the eyes so we are talking about some serious filters for video and photo. One site suggested a 4.0 ND
NOT a .4 or 4x!! I couldn't find any stronger than 1.0 on BH's site but I didnt look real hard.
Anyway, I'm not going to chance destroying my cameras.
Allan Black May 19th, 2012, 07:51 PM I remember reading there were reports of brand new Sony video cameras having sensor damage through the air cargo deliveries from Japan being bombarded with rays from solar flares during the flight. Sony started diverting those flights to avoid this. Delta takes this seriously ..
Delta reroutes planes following massive solar eruption | Fox News (http://www.foxnews.com/scitech/2012/01/23/strongest-radiation-storm-in-7-years/)
A google shows many forum folk think like Robert.
Cheers.
Craig Kovatch May 19th, 2012, 08:40 PM I do have an x16 ND filter for my camera which I use for daytime timelapse with long exposure times, but this probably won't be enough. I'll sit this one out as well. Thanks for the advice guys.
Craig.
Duncan Craig May 20th, 2012, 01:40 AM ND500 (http://lightcraftworkshop.com/nd500.html)
Might be some use in these situations...
Luc De Wandel May 20th, 2012, 03:56 AM I've shot solar eclipses many times (see attached example) without any specials filters on my Canon 5D mk II. Just close the aperture to 22, set shutter speed to 1/5000th or so and reduce the ISO to the minimum. Videocamera's are another story of course, but with the aperture almost fully closed and the most dense ND-filter switched on, there 's should be not problem, I guess. I's all just a matter of lumens...
Dustin Moore May 20th, 2012, 05:46 AM The 5D has a physical shutter that will keep the exposure short. The
EX video cameras have no physical shutter to prevent the sensor from heating up.
If you want to photograph the sun safely you need something with an optical
density of 4 or so. Baader Planetarium and resellers sell some 3.8 film that
is good. It is too late to be mailing ordering in stuff for the eclipse.
You might be able to find welder's glass at a local welding supply store.
Remember, don't look into the sun with welders glass unless it has a density of
5.0 or so. The 4.0 is great for the camera but too bright for a person.
The problem with the welders glass for cameras is that it isn't polished
flat so you will get some aberrations from it.
Mylar may also work but I haven't tried it so I don't know if it as easy as
going to the party supply shop and picking whatever is off the shelf. The
Mylar tends to be optically flatter than the welders glass.
If you do have a cheap telescope (2" tasco type thing) you can do a projection from
the telescope on to a white sheet of paper. Quite amazing what you can see then
when it is blown up to decent size. Not as good for photography but great
for showing the kids what is going on because you can point to it and it is
big.
Dustin Moore May 20th, 2012, 06:17 AM One can do some math to see if the F/22 plus the 1/64 ND is enough.
If we compare F/22 to F/5.6, that's about a factor of 0.06 in the intensity on
the pixel. If we throw in the 1/64 ND we get another factor
of 0.0156. Relative to the f/5.6 no ND position, the F/22 plus the heavy ND is
0.06*0.0156=0.0009 times the intensity.
This is similar to using an ND with optical density of 3,0 or so, not enough. If
you had an optical density 1.0 ND filter that you could throw on the front of the EX1,
that would get you to the optical density of 4.0 equivalent.
Also, if you did try to do this a lot sun light energy is being dissipated
in the iris and the ND filter. The cement in the glass is also going to get
hot which is not something one wants.
Replacing the lens on an EX1 is a ~$2000 operation so probably not worth it in
the end.
Annen James May 20th, 2012, 10:50 AM I've got a Heliopan vari ND. If I use all the ND on the camera, crank the Heliopan all the way, f22, and use 1/5000th, do you think i'll be in the ball park, or is it just not worth it?
Tyler Schimpf May 20th, 2012, 01:06 PM Would a Letus adapter help at all?
Donald McPherson May 20th, 2012, 01:57 PM What about pinhole photography onto a white sheet and video that.
Cees van Kempen May 20th, 2012, 02:23 PM Also depends on the time of day the eclipse is there. We had a solar eclipse here last year just at sunrise. Shot it with my EX3, no problem at all. Like there is no problem either when shooting a 'normal' sunrise or sunset. We all do so, don't we? So it is not necessarily so that filming the sun is risky.
Annen James May 20th, 2012, 05:24 PM I'm going to try tonight. I'm in Salt lake, and the eclipse is from 6:30p to 8:30. I'll fire off a timelapse and post the results. I tested with the heliopan, with all the ND it had, 2 ND on the camera and 2000th shutter and the sun looked fine in the viewfinder. We'll see!
Annen James May 20th, 2012, 10:19 PM https://vimeo.com/42525016
Alister Chapman May 21st, 2012, 12:59 AM On a video camera the shutter makes no difference whatsoever as it is not actually a shutter as such, just a shorter sensor readout speed. The chip itself is always continuously exposed to light.
You must use external ND of some sort to shoot directly into the sun for extended periods. If you don't you risk damaging not only the sensor, but also the cameras built in ND filters which as they are behind the lens can be overheated.
The best is proper solar film available from any good telescope supplier, it's not expensive. Normal ND's while reducing visible light often don't reduce infra-red sufficiently to reduce heating effects.
Jack Zhang May 21st, 2012, 02:13 AM Contemplated doing this when it was sunny in Vancouver. Then the rain came the day it was supposed to happen...
Did a timelapse of the changing brightness under the clouds. I know, boring right?
I went F16 with ND64 on that sunny day, and I couldn't bear zooming in. Still overexposed, so I was not going to directly point my EX1R at the sun. Ended up on that cloudy day locked in at 1/60th shutter, S&Q 1fps recording at 30fps, ND1, and F4.
My editing machine is undergoing a major modification at the moment, so I can't edit together at the moment.
Jack Zhang May 22nd, 2012, 10:51 PM Here's the video now that my edit machine is back up and running:
http://vimeo.com/42675521
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