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Leonard Levy March 19th, 2010 12:44 AM

help custom white balance on 5D
 
I have just spent the better part of a day trying to understand how to use my friends 5D. Either I have gotten alot dumber recently or this is the worst manual I've ever seen and the most un-intuitive camera I've ever touched.

Maybe I'm just not used to DSLR's.

What is up with white balancing? Why can't I just hit a button and white balance like I can with a point and shoot?

OK all ranting aside , can anyone explain in English how to get a custom white balance?

I gather I have to shoot a white card then use that as a reference . But whenever I try to follow the manual's instructions nothing happens. It says to choose the custom white balance icon in the white balance menu item - The choose the shot wish to use for a custom white balance - Well I don't see how to choose any shot. Nothing happens at all. I am hopelessly lost with this beast.

Jon Fairhurst March 19th, 2010 01:52 AM

You're on the right track.

Shoot a white card, preferably in large RAW format. Make sure that it's not overexposed. It doesn't have to be in focus or cover the whole frame.

Select Custom WB in the WB menu. It looks like a flower to me. Make sure to hit "SET" to select it. Sometimes I have put my cursor on the selection, then I hit another button, like halfway on the shutter release, and I think I've selected it, but I haven't.

Okay, one more step: Navigate the the menu item below WB. This is where you select the source for custom WB. Select it. Press SET and it will bring up your most recent photo. Hit SET again and you're good to go.

Best of luck!

Leonard Levy March 19th, 2010 09:52 AM

Thanks Jon,
Now I get it. Still sucks though.
What's happening exactly here? Is the camera analyzing a Raw photo to make determinations for WB. Why do they say it doesn't matter what color temp you use when taking the pic. And what does that say about the color temp of the photos themselves? Are they always raw as well like in a Red? Don't look like it in the viewfinder, or is that just an overlay. But video isn't raw though. Sorry to be so dumb.

Also is there a way to store a whole bunch of custom White Balance photos to draw on when working fast? You don't want to have to search through hundreds of stills.

I would imagine that with this H264 picture that you want a WB as close as you can get it in the field before color correction later.

I just bought a T2i which doesn't have the Kelvin adjustments. Would this be a serious handicap?

Jon Fairhurst March 19th, 2010 11:24 AM

Hi Leonard,

Yeah, the photo images are analyzed right off of the sensor to measure the white balance. Come to think of it, I would guess that Custom WB works when snapping JPEGs too. The photo is taken in RAW, the WB analysis is done, and the JPEG is stored with a WB estimate. So when you select an image for custom WB, the camera just grabs the number(s) and sets the WB adjustment.

There are a few ways to set WB.

1) Select a preset, such as sunlight, shade, etc.
2) Set a color temp. (Not available on all cameras.)
3) Set the basic color temp and apply a 2D offset. (The 5D has WB Offset. Not sure on the 7D and T2i.)
4) Custom WB from white card. (Reflect the light.)
5) Custom WB from an Expo Disc. (Look at the light source and diffuse the light.)

You can select any photo on your card for custom WB. Usually, I snap a new one. But often, I just grab a preset. One example is for shooting sunsets. If you custom balance a sunset, the result will be neutral or blue. It's better to choose a preset, such as cloudy or shade, to show off the orange hues.

Also, you don't always want to be changing your WB. We did a snow shoot on a cloudy day with an Expo Disc using a new custom WB for each shot. The color of the snow ended up being all over the map. We were near trees and a house with warm tones. It's possible that we kept the skin tones really consistent, but small changes in the color of the snow were really apparent. It made for more work in post, but we were able to grade it just fine.

The bottom line is to not be afraid of the presets, and to not worry about getting each shot perfect. Sometimes a consistent color balance from clip to clip is better than a WB that bounces around.

As an example, snap a photo including a white item in a shot with complex colors. Have something cast a subtle shadow over part of the white item. Open the image in your photo editor. Click the WB eyedropper in different areas of the white item. Watch how the color of your image varies. That's the kind of variation that you risk from clip to clip. I'd rather have all my clips slightly warm or cool than to have each clip vary.

Best of luck with your T2i!

Leonard Levy March 19th, 2010 11:42 AM

Jon,

Thanks for the input.
I've been shooting for many years so I do understand what you were saying about sticking with one white balance throughout a scene. Good tip especially about snow though.

For outdoors I agree that the pre-sets look like they give you a lot of choice. I was wondering more about flourescents or even creating a series of presets that might work like the Kelvin choices in the 7D and the 5D. So you could have presets say for interior home tungstun so that its not to warm or to warm up a tungstun setting? I think the T2i will still have the R-B and M-G compensation, so that will help though speed concerns me. I'm trying to think ahead about what is needed t be able to move as fast as I'm used to shooting B roll in video.
Maybe that will be impossible with a DSLR though at least regarding color.

I'm wondering also if the heavily compression of the DSLR video would make it more important to be pretty close on color than it is on video. How much color correction can it take before it gets destructive - say dealing with florescents. I'll have to do my own tests.

Its a brand new world.

Jon Fairhurst March 19th, 2010 04:38 PM

That's a great idea. Shoot a number of photos with varying color temps, store them on your card, and use them as custom presets. Brilliant!

I don't have the T2i, so I can't verify that this would work, but it seems reasonable.

As I recall from a Canon Intermediate DSLR class I attended last year that their cameras don't look at the whole frame for white balance. That means that you could include some text along the edge of your images that specify the color temp or offsets that you've applied.

Of course, we want to get the WB close, but I find that making small adjustments isn't too destructive. Don't sweat perfection, but don't confuse tungsten and daylight either. :)

I believe that a good exposure is much more important. On our snow video, we used histograms, and while we avoided clipping, the exposures needed a lot of tweaks. This added unwanted contouring.

On the other hand, more recently we've been shooting with Magic Lantern's zebras. We can simply nail the face tones (at 0xb000), and avoid clipping (0xf000). We had problems with the shadows though. Don't trust the LCD!

Recently, I bought a Marshall HDMI monitor for my employer's kit. It includes false colors. I'm REALLY looking forward to using it to nail all the levels in a single view.

One reason that exposure is critical is that the RAW sensor info gets an S-curve applied during encoding. If faces are in the middle, you have many bit values to work with. Put the faces at one end or the other, and the bits get shallow.

Using ML zebras, we shot a seven minute film in which the face tones all matched right off the card. We had to tweak just four clips to get everything to conform from clip to clip.

Regarding color correction, I just picked up Colorista. If you start with well-exposed material, you can grade very nicely without tearing things up. If you use high bit depth in After Effects, Colorista has an almost buttery feel to the controls.

FWIW, we're shooting with the Natural picture profile with Contrast and Sharpness at minimum and Contrast just under mid level. It looks dull out of the camera, but lets you push things around.

Leonard Levy March 19th, 2010 07:29 PM

Jpn,
Thanks for the suggestions. We did some testing also and agree about contrast and sharpness down. There is no magic lantern for the 7D or the T2i yet ( I hope?) as I would love to have zebras.

I had to return the 5D this morning so didn't try out the multiple white card idea. 1 question is could you make a folder that only held your white cards, and is that easily accessible when you do the white balance routine. 2nd is how much trouble is it to save that folder everytime you download & erase cards.

Let me know how you like the Marshall. Oddly I had some input on that monitor. Last year at a trade show they showed me a prototype and the flesh tone colors were set at 80% and I told the salesman he was way overexposed for flesh - apparently that's what his engineers had been told. He got really upset and brought a bunch of other guys over to talk to me . I saw him again at the same show in SF a month ago and he flagged me down to show off how they fixed it. But now the flesh tone color was at 55% which I felt was now a little too low for my taste - I like 60% for HD.

I may need an HDMI monitor. I own a Panny 80W but its heavy and needs a blackmagic adapter to turn the HDMI into SDI. But its a great monitor with a waveform.
Don't know if the cheaper alternatives like the Lilliput or the Ikan are worth a damn. I like having a waveform. The Small looks good, but no waveform. Marshall says they'll give me a discount as a courtesy but I was dubious about the color thing.
You can email me privately about the Marshall.

Just looked at the T2i manual. It has the same color balance system as the 5D but no Kelvin adjustments . However the Blue / Amber bracketing adjustment looks like its about 100 degrees @ (5 mired units). In combination with the presets you could probably hit about every Kelvin temp though its a little slower for sure. May not have folders though.

Jon Fairhurst March 19th, 2010 07:54 PM

Hopefully, Magic Lantern will unlock the 7D and T2i cams. By that time, it should include scripting. I'd love to be able to quickly cycle through key zebra levels at the touch of a button. The problem with the current ML code is that it's slow and clumsy to operate. Then again, nailing the exposure saves a ton of time in post and re-shoots, so I can't complain.

I don't know that folders would work for WB pics. The camera saves all the photos in a flat structure. Still, you could keep a folder on your PC and copy them over.

From Magic Lantern, it's a bit of a logistical challenge. I start the day with my ML files on the cards and in a folder. The wrangler can run a full card to the PC and offload it to a couple of drives. Then he/she can delete the clips from the card. Some always want a fresh format. To do that, you need to run back to the camera, format, run back to the computer and load the ML (or WB) files. Personally, I've never had a failure just removing the files.

Some claim that this will cause fragmentation, but CF cards are fragmented by design to spread the wear across the chip. It's not like it has to move an armature back and forth to read the data.

So far, I like the Marshall. The 5D2 switches to 480p, so the monitor goes dead for a moment or two. The aspect is then wrong. A press of the button fixes it. A press of another button toggles false colors. (False colors made the sale.)

I'm awaiting delivery of the batteries that were "lost" during the UPS shipment. I'm also waiting for mounting hardware. I've played with the monitor, but I haven't yet used it in anger.

Leonard Levy March 19th, 2010 11:35 PM

Let me know if the false colors are working well for you. 55% for caucasian faces sounds low to me so I fear it would tend toward underexposure - though that's better than the reverse. Maybe it works fine though.

Does the peaking work well? I have that on my Panny but its too aggressive and sometimes shows red peaking where it really isn't sharp yet. The peaking on the EX-1 viewfinder in phenomenal and totally reliable.

Jon Fairhurst March 20th, 2010 12:32 AM

Yeah, 55% seems low to me too. 60 - 65% seems a bit more desirable. Though, frankly, as long as I get the shadows out of the noise, the whites from clipping, and the faces in the linear part of the curve, I can do what I need in post.

BTW, the 0xb000 zebras in Magic Lantern would be 11/16 or 68.75%. From my experience with the 5D, that's a bit on the hot side. It starts to get into the curve and can start to look a bit plastic.

With experience, I should be able to cheat the 55% skin tones toward the hot side and get a good result.

Leonard Levy March 20th, 2010 01:18 AM

Most people know used to shoot SD at 70% but went down to 60-65% with HD.

Steve Cahill March 20th, 2010 05:02 AM

Jon can you elaborate...."So far, I like the Marshall. The 5D2 switches to 480p, so the monitor goes dead for a moment or two. The aspect is then wrong. A press of the button fixes it............"

Can you further explain the button on the monitor, does it keep the 16x9 or just enlarge the picture in SD?

What sharpening tools in post do you find most useful when shooting 5D2 when in camera sharpening is set to none?

Jon Fairhurst March 20th, 2010 10:04 AM

You can assign functions to hot keys. The one I press is simply an aspect change. I wish I could program a size and position too. Sometimes I want to see the information around the image. Other times I'd like to fill the screen with the video. (In general use, I need to see all the info when I set up the shot. Once I start recording, I just need to see the video. Then again, it's nice to be able to see the status when shooting so you don't second guess the settings.)

Here's a feature request for future video cams: Give us 16x9 monitors and LCD screens. Fill the display with the image. For photos, put some icons and stuff on the side. And let us specify a 16x9 photo crop. For most of us the biggest display in our homes is a 16x9 TV.

Note that on a DvSLR body, there is no room to make the LCD taller, but it can go wider. The 4x3 photo market would not lose an information with a larger 16x9 screen. And, with full time 16x9, we maximize the use of our monitors.

For sharpening, I usually use the "Sharpening" effect. ;) Seriously, I haven't done anything fancy. In general, they use an "unsharp mask", where they apply a softening filter, subtract that from the original and add the resulting detail to the original.


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