Pointing camera at Sun, etc.

Wed Feb 03, 2016 5:27 am

Hi everyone,
I read in the FAQ that I'm not supposed to point the camera directly at the sun (or lasers, or super bright light sources). I'm sure other camera manufacturers tell you not to do this as well, but to tell you the truth I do it all the time. I guess I'm a bit more nervous to mess up a more expensive camera like this. But I like flares a lot and use them, pointing my camera right into bright objects like the sun or bright HMI's, etc. How seriously do you think I really need to take this disclaimer? I'm not interviewing the sun or anything, but I do let it hit the lens directly and at a pretty open aperture for a few seconds at a time. I'm happy avoiding lasers, but if I have to avoid the sun I'm in trouble. I never thought about it too much on rentals before, but now being an owner, I don't want to mess up my baby's eye!
Also, I remember on a commercial I shot one time with an Alexa I got a purple circle in the sun when it was in frame, and I was hoping that problem was fixed... is that still happening to people? I've never noticed that with other cameras.
Thanks!
Stout Film
 
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

Re: Pointing camera at Sun, etc.

Wed Feb 03, 2016 9:54 am

Hi,

first off there is a real possibility of damaging the sensor by pointing it at the sun. The lens in front of it acts like a magnifying glass and will focus the energy on a very small area. This effect is even stronger with lasers and we have seen sensors damaged from very short exposures to lasers. While it is possible to shoot towards the sun it is necessary to take precautions by adding sufficient filtration and reducing the time the sensor is exposed to the sun. This also applies when the camera is not recording or is switched off. In general if you would hesitate to look at it with your own eyes you shouldn't point the camera sensor at it either.

As to the purple circle in the sun you describe, that is generally called the black sun effect. This effect can be seen on other cmos sensors as well and it occurred on the ALEXA when it was overexposed by more than 8 stops beyond clipping. This has indeed been corrected in the ALEXA mini.
Silvan Liu
Service ARRI East Asia Pacific
Silvan Liu
 
Posts: 35
Joined: Mon Nov 23, 2015 7:11 pm
Location: Hong Kong

Re: Pointing camera at Sun, etc.

Wed Feb 03, 2016 11:47 am

I second that, Silvan!

Think of it like this:
https://www.youtube.com/watch?v=N7nJ3wIxt3o

So in short:
Timelapse of the bright Californian sun moving along the cloudless sky - bad idea.
Shooting in a club - disco lights, moving lights, lens flare-pans - will do.

Caution with lasers though!
This might result in something like this - damages photosite-clusters on the sensor:
laserdamage1.jpg

laserdamage2.jpg
Jan Heugel
Application Engineer
Jan Heugel
 
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Joined: Wed Aug 13, 2014 3:15 pm
Location: Munich, Germany

Re: Pointing camera at Sun, etc.

Wed Feb 03, 2016 6:04 pm

Hi,
it is also fair to say that ARRI cameras are not more vulnerable to sunlight and laserlight than other digital cameras and people point cameras into the sun and it works. You should probably not leave cameras pointing into the sun for a long time or focus the sunlight on a very small spot. Regarding lasers it is also dependend on the power of the laser - a simple laser pointer will probably not damage the sensor.

We cannot give clear recommendation as situations vary and the danger to damage the camera is a real one. If you do it, you are doing it on your own risk.

We had the black sun effect fully corrected on ALEXA Mini, but we chose to slightly take it back as the overall image quality benefitted from it. In extreme situations a slight black sun effect may still appear.

Best,
Michael
Michael Jonas
 
Posts: 20
Joined: Thu Mar 26, 2015 3:28 pm

Re: Pointing camera at Sun, etc.

Wed Feb 10, 2016 4:02 am

Thanks guys, this is helpful information. Yes I think avoiding lasers and long timelapses with the sun in the frame are totally avoidable for me. I will proceed with caution pointing towards the sun for flares, etc, and not hold it there for long periods at a time, and being sensible with aperture and filtration. But since I've never had an issue with any other camera, and Arri's are no more susceptible, I'll also try to not let my paranoia get outta control :) Thanks for all the thoughts on this helping me shoot safely!
Stout Film
 
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

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