Day for Night
Posted 30 July 2005 - 12:27 AM
shoot on a bright sunny day with tungsten film to increase blue.
Posted 30 July 2005 - 01:24 AM
Im not sure what using two polarizers will achieve since..... two polarizers will cancel each other out at an angle of 90 degrees to each other letting very little light pass through.
So lets see ...the polarizer in front of the lens lets polarized light through but the one behind it then basically as you rotate it away from 90 degrees allows some light to pass through....Its acting more like a variable ND filter cutting light(allowing less or more light to pas through as you rotate it).
So im not sure what you intend to achieve..with two polarizers for day for night??
Here are some interesting links on polarized light and polarization
with examples :To cut glare off the road buy polarised sun glasses with their polarization axis perpendicular to the road.
This one is fascinating reading about
Polarization Compasses.... how auroras are polarized.....bees and polarization...the vikings and polarization.....Display sytems and polarization ( like LCD screens have a polarisation filter)
So lots of interesting stuff on Polarized Light .........
Posted 30 July 2005 - 08:12 PM
Posted 31 July 2005 - 05:25 AM
Rotating two polas against one another to darken a scene?
I used to do that shooting Slit Scan many years ago! to fade out part of the image! Slit Scan was the effect Doug Troumble (spelling) used on 2001!
Stephen Williams DP
Posted 31 July 2005 - 04:39 PM
I think it's an interesting idea but as an all in one solution it's rather contingent on what you're shooting...
Posted 31 July 2005 - 06:35 PM
If you use one pola which blocks some of the polarized light, then underexpose, your are also underexposing your highlights, effectively reducing your contrast range within the image. If you use both a linear and cirlcular pola and do not underexpose your highlights, but let your shadows go black, your are increasing your contrast and yielding a more extreme result.
I guess you have not tried this.
Posted 06 August 2005 - 12:12 PM
I've tried it by eye but it doesn't make day look like night. There are a lot of things you need to do with day for night photography. Keeping the sky out, keeping scene backlit by the sun, putting massive sources in windows to simulate failing light etc.
What worries me most though is calculating the exposure. A polar is 1 2/3 stops okay. Two is 3 1/3 in theory but that depends on the rotation. You can achieve almost no light transmission.
Posted 06 August 2005 - 03:20 PM
When he talked about it, I think he mentioned something about wanting to get rid of hard reflections on the water by using the Polas, since hard reflections on waves would clearly show the sun, and be very hard to paint out digitally. The sky was in shot (but not the sun), and digital stars were added in Post.
I don't think the film has been released yet.