Difference between Auto WB and Custom WB.

In this case under tungsten lighting at night, indoors.

Since my XS's WB presets weren't giving a good result for shooting in these conditions(my house) I decided to try out Cutom White Balance. As I don't have an 18% Grey or White card, I had to use house hold paper.

These are my results, ordered as AUTO WB-white reference-Custom WB:

In my kitchen under one tungsten light with AUTO WB

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Well, one technique that has been put out is to use a white paper coffee filter over your lens. Switch to MF, take the shot and it becomes your target for either a custom WB or, if you shoot Raw, your reference shot for quick WB adjustment.

tonylong wrote in post #10136717
Well, one technique that has been put out is to use a white paper coffee filter over your lens. Switch to MF, take the shot and it becomes your target for either a custom WB or, if you shoot Raw, your reference shot for quick WB adjustment.

Hmm, should try that too. Though I imagine in that case I'd have to point the camera toward the light source right?

fedaykin wrote in post #10136743
Hmm, should try that too. Though I imagine in that case I'd have to point the camera toward the light source right?

No, just point it into the scene -- the filter collects and diffuses the ambient light. It's worth a try. For a lot of indoor/artificial light situations, WB is a "best guess" on the part of the camera, so you do your best.

tonylong wrote in post #10136768
No, just point it into the scene -- the filter collects and diffuses the ambient light. It's worth a try. For a lot of indoor/artificial light situations, WB is a "best guess" on the part of the camera, so you do your best.

Haha I just saw a DIY project someone did where he cut out a round piece of coffee filter and placed it inside a UV filter to use as an Expodisc of sorts. Seems like a good idea.

Why does it seem that incandescent light is so hard for AWB to handle? AWB does a decent job in many other situations but misses by a mile under a century old lighing technology.

mike_d wrote in post #10136842
Why does it seem that incandescent light is so hard for AWB to handle? AWB does a decent job in many other situations but misses by a mile under a century old lighing technology.

I've thought about this myself, would like to know as well.

Good idea for quick raw white reference

Thank goodness I shoot RAW, I don't need to bother about this, lol

Did you try setting your WB to tungsten?

mike_d wrote in post #10136842
Why does it seem that incandescent light is so hard for AWB to handle? AWB does a decent job in many other situations but misses by a mile under a century old lighing technology.

It might be due to the cyclical nature of incandescent lighting. As it runs at mains voltage, the lights are actually flickering due to the frequency cycle (50hz in the uk, 60 in US IIRC). Its imperceptible to the human eye which has approx a 25hz refresh (not sure what the correct term is ). As the camera will sample the light in an instant (way less than the 0.02secs of the cycle), it will inevitably miss part of the cycle and hence the WB will be off.

This is also the reason that at certain shutter speeds in gyms and other indoor shoots you get inconsistent exposure across a frame (green or yellow tint at one side)

RAW is of course the easiest solution as you can adjust the WB yourself to suit.
Incandescent is a setting which takes account of the cycling (and doesnt sample the light conditions) therefore giving more consistnt results.

I use CWB all the time, the exact way you did it. A nice white sheet of paper. I just can't imagine that a "special" piece of something white would be all that much better.

Dave

Gatorboy wrote in post #10137404
Did you try setting your WB to tungsten?

yes, and it came out almost exactly like the Auto WB setting.

neilwood32 wrote in post #10137521
It might be due to the cyclical nature of incandescent lighting. As it runs at mains voltage, the lights are actually flickering due to the frequency cycle (50hz in the uk, 60 in US IIRC). Its imperceptible to the human eye which has approx a 25hz refresh (not sure what the correct term is ). As the camera will sample the light in an instant (way less than the 0.02secs of the cycle), it will inevitably miss part of the cycle and hence the WB will be off.

This is also the reason that at certain shutter speeds in gyms and other indoor shoots you get inconsistent exposure across a frame (green or yellow tint at one side)

RAW is of course the easiest solution as you can adjust the WB yourself to suit.
Incandescent is a setting which takes account of the cycling (and doesnt sample the light conditions) therefore giving more consistnt results.

Thanks, I didn't know that.

tracknut wrote in post #10138394
I use CWB all the time, the exact way you did it. A nice white sheet of paper. I just can't imagine that a "special" piece of something white would be all that much better.

I'm considering getting a white card or something but mainly for the portability.

Question Do you guys have a preferred way of adjusting WB in post process? Auto correction, stretch contrast? Using levels, curves?

In my case, I try to get it right in camera, but if it's off I generally use the white balance selector in curves to adjust.

Dave

In most cases when I'm taking casual photos I'll use auto white balance, it's just easier to have the camera decide and in 95% of the time, it's near spot on.

When I'm taking formal photos for a friend, like engagement photos that can't redone easily and need to be right proper, I'll use custom white balance using either a gray card or Expodisc. I can adjust in post but it's so much easier to have all of the photos already done even before I down load them.