Pointing a a RED at the SUN

[JohnF]

If you're shooting T-lapse there is a machine that rotates a lens cap like protector over the front of the lens between shutter firings.

Works something like this.

Activate machine

Starts exposure
Ends exposure
Covers Lens
Waits selected interval
Un-covers Lens
Starts exposure...

etc etc

Ends all worries about external conditions f**king up your shot and camera but I've forgotten the name of the bloody thing but I think that Panavison hire it out.
(I made one once, fairly simple too when using electro-mechanical type cams but all digital cams like RED might require more skills)


JohnF

[Jim Arthurs]

John, it's simply called a "capping shutter". Lots of different types, most are home brewed DIY'ish...

Most all older cameras with spinning mirrors would benefit from a capping shutter when there's long delays between exposures, as there is always a greater potential for light leak vrs something like a rack-over Mitchell...

Over the years I've found that if you want to test the film path of any camera for the faintest of light leak, simply run film through it at noon on a bright day at a frame per second or slower...

[JohnF]

Cheers Jim,

That was bugging me as it was on the tip of my tongue!

JohnF

[I Bloom]

Aside from ND's are their specific filters could you use to protect the chip from the sun?

And while I'm at is there a rough guide to just how much direct sunlight the chip can handle per lense, per time of day. Be great to have a chart, if you end up doing a lot of timelapse.

IBloom

[JohnF]

Outside of ND's (and polarisers) there is very little one can do about it.

If your T-lapse is an all day "sun-in-shot" job then a capping shutter is the best protection. (or sit with your camera shading the lens manually in between frames).

At sea-level the suns power is at both infra red and visual wavelengths go to the top of high mountains and you start to get a bit more UV thrown in too.
Because of the sheer amount of energy focussed by the lens and the broad wavelengths involved there is very little one can do except bung strong ND's on the front or cover/shade the lens.

JohnF