Wb xf305

[Matt Ford]

I always manual WB. I have noticed though if I try and dial in the equivalent into preset, say 3200k the settings have a different cast and I cannot get them to match by scrolling through temp settings in preset. So a manual setting of 3200k is cooler than the dialled in preset equivalent, which is warmer! The preset I have to say looks more accurate on the LCD.

Am I missing something?

[Chris Dickinson]

You're not missing anything - its pretty common with all cameras.

I am not techie enough to go into details but my understanding is, in very basic terms (NB: I am not being completely accurate to the way the signal is processed):

the image is composed of R, G and B, and a white balance setting of, for example 3200K, can actually be composed of different values of R, G and B. Hence, two settings at seemingly the same 3200K can have different looks as they are composed of different RGB values.

I'd expect the presents dialed-in values to have a better, more balanced look. When doing a manual white balance you may well be subjecting the camera to a light source that is far from ideal - i.e. one that has spikes or inconsistencies which may cause it to overcompensate in certain areas and thus cause a slightly cooler look...

In larger broadcast cameras its possible to go into the WB menu settings and change the R and G gain etc of your A, B and presets, and in the XF cameras you can go into the Custom Pict settings to tweak gain in white balance - you could try this, or go into the colour correction settings...

When white balance I will often do two different white balances on A and B, compare the two and then see if I prefer the look if I dial in the K setting manually... and then just go with what I prefer.

Hope that helps.

Chris

[Martin Koch]

Thanks a lot for this explanation Chris. It makes perfect sense. I used to think that Custom White Balance does automatically adjust the RGB gain when using a non ideal light source with different amounts of RGB. But it obviously does not. I always had a slight color cast even when using Custom White Balance and lighting with matched color temperature. I tried to fix it using the Color Matrix settings but was never fully satisfied.

Thankfully you mentioned this Custom Picture White Balance adjustablility which I had totally forgotten and overlooked. Using this I was able to set a technically perfect WB under my lighting condtions.

What I did:

After setting Custom White Balance I zoomed in on a neutral grey card so it filled the frame entirely.

Then I switched on the Vector Scope and went to Custom Picture > White Balance > R

If there's a color cast the Vector Scope dot representing the neutral color cast free grey will be off the middle. It was indeed by a tiny, barely visible amount.

I was able to adjust the R, G, B gain until the dot was exactly in the middle.

The neccessary movement of the dot (R-2, G0, B1) was optically very, very tiny but the difference was stunning: a technically perfect color cast free image.

[Graham Bernard]

For me this has been the very best thread, on this subject, in yonks. Thanks gentlemen.

I've been experimenting (playing) with the Colour Balance FX in SONY Vegas, and was becoming very aware of the way to "WHITE" by adjusting and adjusting back the RGB sliders and checking Vegas Scopes. That was an eye opener too.

Grazie

[Matt Ford]

Chris, a belated thank you for your response. A great reply. Its mainly interior lighting I find that gives the different colour casts with equal colour settings , but I have learnt to trust my eye with the dialled in value, I have set the LCD to the point where I can dial it back to about right. I have noticed that when I balance the 305 against a Panasonic or Sony 2/3 broadcast camera I can get vastly different values for the same look though, I trust my eye for now!

[Matt Ford]

Originally Posted by Martin Koch

Thanks a lot for this explanation Chris. It makes perfect sense. I used to think that Custom White Balance does automatically adjust the RGB gain when using a non ideal light source with different amounts of RGB. But it obviously does not. I always had a slight color cast even when using Custom White Balance and lighting with matched color temperature. I tried to fix it using the Color Matrix settings but was never fully satisfied.

Thankfully you mentioned this Custom Picture White Balance adjustablility which I had totally forgotten and overlooked. Using this I was able to set a technically perfect WB under my lighting condtions.

What I did:

After setting Custom White Balance I zoomed in on a neutral grey card so it filled the frame entirely.

Then I switched on the Vector Scope and went to Custom Picture > White Balance > R

If there's a color cast the Vector Scope dot representing the neutral color cast free grey will be off the middle. It was indeed by a tiny, barely visible amount.

I was able to adjust the R, G, B gain until the dot was exactly in the middle.

The neccessary movement of the dot (R-2, G0, B1) was optically very, very tiny but the difference was stunning: a technically perfect color cast free image.

Im going to give this a shot. Thanks Martin.

[Robert Turchick]

I just dealt with this yesterday. Perfect explanation and I made the decision to use the preset instead of manual. Worked great! With the explanation of how to use the grey and vector scope, it should be easier to do manual WB accurately! Thanks!

[Chris Dickinson]

Hi - glad to help - and glad my explanation made sense :o)

I have found the XF white balancing to be a little awkward on occasion, but have had more severe results with EX cameras - which at times can been VERY off.

Adjusting the CP white balance the way Martin suggests is a good way to go if you're not happy with the whites.

Its funny - when I started shooting we were using the BVW400 - with nothing more than a b&w VF, and never worried - you pressed the WB button, the camera said 'ok' and all was good... Simple as that! I sometimes think these technical advances just make our lives more complicated! ;)

Chris

[Matt Ford]

Originally Posted by Martin Koch

Thanks a lot for this explanation Chris. It makes perfect sense. I used to think that Custom White Balance does automatically adjust the RGB gain when using a non ideal light source with different amounts of RGB. But it obviously does not. I always had a slight color cast even when using Custom White Balance and lighting with matched color temperature. I tried to fix it using the Color Matrix settings but was never fully satisfied.

Thankfully you mentioned this Custom Picture White Balance adjustablility which I had totally forgotten and overlooked. Using this I was able to set a technically perfect WB under my lighting condtions.

What I did:

After setting Custom White Balance I zoomed in on a neutral grey card so it filled the frame entirely.

Then I switched on the Vector Scope and went to Custom Picture > White Balance > R

If there's a color cast the Vector Scope dot representing the neutral color cast free grey will be off the middle. It was indeed by a tiny, barely visible amount.

I was able to adjust the R, G, B gain until the dot was exactly in the middle.

The neccessary movement of the dot (R-2, G0, B1) was optically very, very tiny but the difference was stunning: a technically perfect color cast free image.

Thanks, much better! only out a little but slight movement make a big difference.

[Mike Ayotte]

Originally Posted by Martin Koch

Thanks a lot for this explanation Chris. It makes perfect sense. I used to think that Custom White Balance does automatically adjust the RGB gain when using a non ideal light source with different amounts of RGB. But it obviously does not. I always had a slight color cast even when using Custom White Balance and lighting with matched color temperature. I tried to fix it using the Color Matrix settings but was never fully satisfied.

Thankfully you mentioned this Custom Picture White Balance adjustablility which I had totally forgotten and overlooked. Using this I was able to set a technically perfect WB under my lighting condtions.

What I did:

After setting Custom White Balance I zoomed in on a neutral grey card so it filled the frame entirely.

Then I switched on the Vector Scope and went to Custom Picture > White Balance > R

If there's a color cast the Vector Scope dot representing the neutral color cast free grey will be off the middle. It was indeed by a tiny, barely visible amount.

I was able to adjust the R, G, B gain until the dot was exactly in the middle.

The neccessary movement of the dot (R-2, G0, B1) was optically very, very tiny but the difference was stunning: a technically perfect color cast free image.

Martin
Is this custom picture W B adjustment a global setting or do you have to do this for each custom picture preset you use?

[Matt Ford]

Im sure its per CP file.

[Mike Ayotte]

Thanks Matt.

[Martin Koch]

Originally Posted by Martin Koch

What I did:

1) After setting Custom White Balance I zoomed in on a neutral grey card so it filled the frame entirely.

2) Then I switched on the Vector Scope and went to Custom Picture > White Balance > R

3) If there's a color cast the Vector Scope dot representing the neutral color cast free grey will be off the middle. It was indeed by a tiny, barely visible amount.

4) I was able to adjust the R, G, B gain until the dot was exactly in the middle.

The neccessary movement of the dot (R-2, G0, B1) was optically very, very tiny but the difference was stunning: a technically perfect color cast free image.

I would like to add an update to the procedure above.

1) A grey card is for setting exposure and will give different (less accurate) results than a dedicated spectral correct white balance card which I use now.

Before step 2 I now go to OTHER FUNCTIONS > WFM and set the vectorscope gain to 5x. The dot size increases but with the 5 times zoom it is much easier to center the dot and it is also 5 times more accurate.

[Matt Ford]

So now we have the manual WB on A + B sorted do we now adjust the dialled in values with the vector scope so it centres under identical natural lighting conditions and Kelvin values? It's a little green in comparison.

Or shall I leave well alone?

[Al Bergstein]

Amazing differences, especially in overcast days with window light. The blue is gone. Colors are right on (at least in the VF & LCD). Thanks for this essential info.