Proper exposure of K-40

[shralp]

Hello Everyone! New to the forum and super 8 in general. I've been shooting on 16mm for years, but I'm shooting a film this year that will be shot entirely in the backcountry on snow, (its a ski/snowboard documentary). I've just purchased a Nizo professional for the shoot and I plan on shooting with K-40 and Plus-x. Can anyone give me suggestions for metering for Kodachrome in the snow for proper exposure? I get the impression after reading various posts that Kodachrome should ideally be underexposed a half stop or so to look the best. I'm just wondering if shooting in an essentially white situation changes this suggestion. Any thoughts on the Plus-x as well? I'm not sure how the light meter in my Nizo is calibrated, i.e.-center weighted, multi point, etc. but I do plan on using my hand held Sekonic the majority of the time since thats what I'm used to using on my Arriflex. Thanks for any input!

[cameraguy]

Generally speaking the cameras auto exposure will expose the snow perfectly but subject may be dark. So overexposing a touch is needed there. The latitude of Super 8 K40 will not be as good as what you are use to in 16mm.

I would personally shoot at least one test roll with the Nizo using the external meter and see how things come out. Since the manual f/stops displayed in the Nizos viewfinder may not be precise and youwould have to "learn" to compensate if it is off.

[Alex]

I agree with everything cameraguy said.

Plus, different camera motor lubricants behave differently as the temperature drops. Because of this, your actual filming speed could be slightly lower.

I definitely recommend "bracketing" some exposures at the location you plan on shooting, and doing it in similar temperatures.

In general, if you are shooting at 24 FPS with Kodachrome 40 in the snow, you'll probably shooting around F 11,...(just a guess, you could end up at F-16, or just barely under F 11.)

Keep in mind, if you have forest type of backgrounds, they can affect your f-stop.
One autoexposure technique to consider is frame your shot so that half of the frame is snow, the other half sky, take that reading and then probably over expose it by 1/2 to 1 stop.

The most important thing is to REMEMBER what you tried, so that you can begin to rely on a tried and true technique.

<font color="#a62a2a" size="1">[ November 29, 2002 09:29 AM: Message edited by: Super8 Filmmaking in the DigitalAge ]</font>

[Greg Crawford]

Automatic metering in snow is problematic....The meter would like to see the world at Zone V (that's Mid gray) or about three stops darker than white snow in sunlight.

If people are important to your scene measure the skin town and set the F stop to that reading.

If you are shooting a scenic then you can measure the snow in sunlight and open up the exposure , making the snow look whiter. Depending do you want any detail in the snow?

I would modify the zone system concept to fit with what I know about Kodachrome and telecine. I would not place pure white snow about zone VI ...no higher than VI-1/2. That means opening up your f stops. If the meter reads F-11 on pure white snow open up the exposure to F8. But that's with good contrast blue sky and green trees in the background bright color skiers on the sloops etc.

If it's a white out situation, I would under expose. F-11-1/2 F-16.

Be advised of a couple of side issues... Kodachrome tents to make pine trees and forests look darker. And on bright sunny days in snow country are very contrasty. The differences between a sun let ready and a reading under foliage is usually 3-1/2 stops. Which is about the range that Kodachrome can Handel.

Don't try to get good looking snow in bright sunlight and grate detail in scenes on the dark side of buildings or in deep tree cover. It won't work without reflectors HMI's etc.

On cloudy days all this talk goes out the window. You have less reason to bracket. Lower contrast rations between bright snow and shadow detail under foliage.

If all this is to teckey for you...just take Alex and Camera Guy's advice and bracket. Have a good time, take some notes as to what you did and why. and you'll be able to learn from your own experiences the next time.

Happy shooting!

[shralp]

I appreciate all the feedback guys. I'll definitely be shooting some test rolls up on Mt. Hood before I begin this film. Any thoughts on shooting with Plus-x or Tri-x? Will it be easier to meter than the k-40? Does it have any more latitude, basically more forgiving, or the opposite. I'm also thinking of shooting my black and white with a yellow or orange filter as well to bring out the sky apart from the clouds a bit and add a bit of contrast. Any recommendations? Thanks!
(I'm also trying to figure out who to order filmstock from in an effort to not get stuck with the malfunctioning cassette shells that cause your image to jitter. Anyone have any luck on this?)

<font color="#a62a2a" size="1">[ October 13, 2002 10:31 PM: Message edited by: shralp ]</font>

[Mike Buckles]

Maybe try a polarizing filter if it's a sunny day to reduce glare on some of the scenes...I agree with doing a test roll first, then you know what looks good to you!

[Alex]

I'm going to start a topic about Gray Cards because I think it isn't as easy as it sounds. [img]wink.gif[/img]

[Actor]

Buy a gray card from a photo shop (about $5 U.S.) Get in close enough so that the gray card fills the viewfinder and note the reading. Then set your exposure manually using the reading from the gray card.

If using a separate light meter get in close enough that the meter is reading light from only the card.

Tilt the card so that a perpendicular to it bisects the angle from the sun to the card to the camera, i.e., as though it were a mirror you were using to reflect light from the sun into the camera.

[Greg Crawford]

Plus X reversal is a wonderful film stock. I love Black and White ......t

Plus X reversal is snappy but to my eye a little more forgiving than Kodachrome.

With that being said choosing black and white or color, seems to me would be a choice based on your goals not the ease of shooting.

As fair as using a yellow filter again test. I have found that shooting at higher elevations can sometimes be brighter than you meter for, creating a little overexposure...also filter factors can be off at high elevations where the color of the light is not what it is at sea level.

I have a lot of experiences shooting large format 4x5 Black and White in Colorado.

[lightfeat]

I really agree with bossjock dp. Kodachrome has a latitude of about 3 stops, which is less than just about any other stock you're likely to use.

Black and white plus x is a much better option for such ultimately contrasty scenery. Snow is super bright, obviously, and I've never shot in it, but it seems that it will be very hard in K40, because it is already so high contrast that even in normal conditions you get a bit of white out or dark underexposed areas. K40 likes flat bland overcast low contrast shots to expose well, or else it looks "arty" which may be OK for your needs.

Hope this is helpful