I've done quite a bit of this stuff and have a few suggestions. I work in 2K and have used many digital images from a Nikon d-70 to replace skies. I lived in New Mexico and like you have seen fantastic sunsets and clouds.
Its good to answer these questions before shooting. Get all that figured out so when you are on set you can concentrate on getting what you need. I don't know how many times I've gone to prep only to find out the visual effects happen the next day.
Never underestimate the power of good planing. I plan carefully because I know when I get on set every thing is there and waiting on me.
I know most of you know this but just in case.
1. keep track of the lens information.
2. you want your clouds to match. Wide angle clouds or sky need to closely match the lighting and lens distortion of you foreground. best to shoot with same lens.
3. if you are needing to pull mattes off the sky be careful and you will get a clean Luma or Green screen . DP can help with your issues and help match color space between a raw still and whatever stock he is using.
4. keep in mind you may want or need to do some tracking. You need a spot to place a tracking mark or two in the shot.
Hope I helped some. If you solve the technical issues during prep you will be free to be creative and possibly get some goods shots.
BMJ
quote name='Roberflowers' date='Aug 9 2007, 02:32 AM' post='187185']
hello all,
I've been discussing the sky replacements with my director, and I've seen the blip on the web with guy doing it in after effects. I'm wondering if anyone has experience with this. After I have shot the scenes that I intend to do the replacement, is their any considerations for what I use as the replacement. Do I have to shoot those sky shots with 35mm motion picture film as well, can it be digital still? if so at what resolution and what format?
We've shot test footage that is being scanned at 2K this week, so we'll be able to manipulate it soon and try different things before we begin principal photography.
any thoughts.
Just for FYI our workflow is this
originate on 35mm,
edit dvcam
2k scan to dpx files
input in Assimulate Scratch
conform/color
output to DS Nitris
output to HD D5 Master
've
