18% grey card and white balance setting

[ivans75]

Okay, I want to learn to master white balance so I bought a set of cards from ebay (white, 18 grey, black) they appear to be just like normal credit card size. I have trouble taking a shot of the card to cover the whole frame. Seems impossible.
Question is that do I really to have the entire cards covering 100% my camera view finder? or can I just take the shot as long as the round circle on the middle of my view finder aimed at the color?
Thanks in advance.

Do you need to set white balance for everything or just leave it as auto on most general purpose, daylight on landscape and shade on indoor portrait?

[ricktas]

If you shoot in RAW, you can easily set your white balance in post processing.

Learning how to use a grey card can be an interesting experience, but for day-to-day use, I cannot recall anyone I know using it consistently.

Your camera is a great tool and for 99.9% of situations it is very good at automatically working out what setting to use. So set it to auto, shoot in RAW, and forget about white balance in most situations. If you shoot in RAW you can correct it on your RAW processor.

[ivans75]

If you shoot in RAW, you can easily set your white balance in post processing.

Learning how to use a grey card can be an interesting experience, but for day-to-day use, I cannot recall anyone I know using it consistently.

Your camera is a great tool and for 99.9% of situations it is very good at automatically working out what setting to use. So set it to auto, shoot in RAW, and forget about white balance in most situations. If you shoot in RAW you can correct it on your RAW processor.
Yeah thanks Rick, when i first started i used auto wb as i didnt understand much about it. Then after reading some articles about it i was tempted to look more into this as i want to have my shot appears as it should be (white is white / black is black) then i use different settings for different occasions as i said above. But to be honest it doesnt make any difference in my eyes on my pc screen than auto setting so i wanna see if using grey card makes some difference or better. And you re right i can adjust everything on post process as i do shoot raw

but yeah i think u re right i ll set it on auto to make my life easier :)

[arthurking83]

Okay, I want to learn to master white balance so I bought a set of cards from ebay (white, 18 grey, black) they appear to be just like normal credit card size. I have trouble taking a shot of the card to cover the whole frame. ....

So, if you want to take a WB reference image to set up a custom WB in camera, just get the card as close to the lens as possible while still trying to keep the current ambient lighting source on the grey card(or white card .. doesn't matter which).
Doesn't have to be in focus either .. just the colour has to be the predominant colour in the image.

That's just one way to use a grey card.

Like Rick said, you shoot raw, and set WB in PP via your software.
This in itself has multiple meanings.

eg.
1. you can do it the easy, but less accurate, way where you guess the WB in your software either by choosing an ambient lighting setup(eg. incandescent, or cloudy, sunny, fluorescent .. etc)

OR!

2. you can use this type of grey card the way it's designed to be used.
That is, place it in the scene you want to whitebalance and use it as the reference white/grey/black point for PPing via your software.
Use the WB dropper tool in your software(if your software doesn't have this feature, change software!!)

The obvious observation now is that your image will have a white/grey/black card in it if you do it this way, and will look silly/ugly/messed up/etc. Clone it out, or use that as a reference shot only.
Your software should also allow the ability to set WB on any image in the series using a single reference image.

ie. you'd select whatever images were shot in those ambient light conditions, and use that same 'click to grey' WB value made via the image with the card in it.
Alternatively, the cards are made small like that so that they don't take up a lot of physical area in a scene .. if your software has cloning, you use it first as a WB reference point. Once set, clone it out of the image!

[John King]

Some cameras can use a plain white sheet of paper to obtain a custom WB. What brand /model do you own?

[ivans75]

Some cameras can use a plain white sheet of paper to obtain a custom WB. What brand /model do you own?
Thanks i ll try using a white reflex paper sheet and see how it goes. I am using 5diii

[John King]

I don't know what the 5Dlll needs. All my Olympus cameras can use a sheet of plain white paper for CWB.

Check your manual.