Saving the WB Shift//BKT setting (1D MKIV)

[mgrabow]

So, I ocasionally shoot pics and videos of my reef tank with my Mark 4.   However because of the 20,000K color temp of the aquarium lights some white Balance adjustmentsn are needed.   I register a white balance reading to the camera but that only gets it in the ball park.  I need to fine tune it with the WB SHIFT/BKT feature.   However I cant find any way to save it so I can go back to it later.  

Here is a vido in case you all are curious...

http://youtu.be/1wNoDkaKSeA

[mgrabow]

Thanks for all the suggestions.  and I know it can be corrected in photoshop.  Apparently the WB?SHIFT can not be saved to be called up again later.    I will work on my photoshop skills.

[jrhoffman75]

See page 239 of the camera manual.

[mgrabow]

Thanks JRHOFFMAN as this is close to the perfect answer.   It dows save all settings and thus achives what I am looking to do.  However it saves it to the media card and as most of us swap cards regularly it is an issue.

[RobertTheFat]

---

@ebiggs1 wrote:

If he is using RAW and PS, it should not matter.

---

Is that really the case? It's something I've wondered about for a while. When you adjust WB in post-processing, the only way to do it is to remove the colors you don't want until the color balance is satisfactory. Inevitably that costs you light and increases the probability that you'll have to increase the brightness to compensate, with the possibility of increasing visible noise.

OTOH, if you can set the WB correctly in camera and the camera is smart enough to adjust the exposure accordingly, you may not have to apply as much compensation in post, which should reduce the effective noise level. Are cameras that smart, or am I just dreaming?

[ebiggs1]

Bob from Boston,

Not exactly.............

When you make an exposure the sensor records the amount of light that hits each pixel, or photo site, whichever you cal it. It records it as a voltage level. Depending on the camera either 12 or 14 bits depends on how much is recorded. If 12 bits then each pixel can handle 4,096 brightness levels, if 14 bits then it can record 16,384 different brightness levels. This is all that is saved by the camera.

In raw mode when it is later loaded into PS and then saved as a TIFF or PSD file it can be exported in 16 bit mode. The 12 or 14 bits are then spread over the full 16 bit workspace. A JPG is only 8 bit mode and you can only ever have 256 brightness levels to work with.

There is no WB saved in the RAW file. It holds exactly what the sensor saw and recorded. Nothing more. Nothing less. This allows you to set any color temperature and/or WB you want with no image degradation. There is a cheat sheet, however, saved by the camera so the WB it saw can be applied.

There is no free lunch but shooting RAW and using PS is the best way there is to make a photo be the best it can be.

So this is true, ebiggs1 wrote: "If he is using RAW and PS, it should not matter."

[RobertTheFat]

---

@ebiggs1 wrote:

Bob from Boston,

Not exactly.............

When you make an exposure the sensor records the amount of light that hits each pixel, or photo site, whichever you cal it. It records it as a voltage level. Depending on the camera either 12 or 14 bits depends on how much is recorded. If 12 bits then each pixel can handle 4,096 brightness levels, if 14 bits then it can record 16,384 different brightness levels. This is all that is saved by the camera.

In raw mode when it is later loaded into PS and then saved as a TIFF or PSD file it can be exported in 16 bit mode. The 12 or 14 bits are then spread over the full 16 bit workspace. A JPG is only 8 bit mode and you can only ever have 256 brightness levels to work with.

There is no WB saved in the RAW file. It holds exactly what the sensor saw and recorded. Nothing more. Nothing less. This allows you to set any color temperature and/or WB you want with no image degradation. There is a cheat sheet, however, saved by the camera so the WB it saw can be applied.

Yes, I understand all that. But a camera in automatic WB mode computes an adjustment that must be made to the relative strengths of the recorded R, G, and B values in order to normalize the image to what the human eye would think it sees. To avoid the risk of blown highlights, the adjustment must take the form of a reduction (applied to all pixels) of the strength of one or two of the three colors. But at least in principle, the camera knows what that adjustment will do to the apparent brightness of the image and could increase the exposure accordingly.

One could argue that the exposure correction is meaningless, since turning up the overall brightness in post-processing has the same effect. But we've been led to believe that turning up the brightness increases the effect of noise, while increasing the exposure does not. So letting the camera adjust the exposure should result in slightly better IQ. No?

There is no free lunch but shooting RAW and using PS is the best way there is to make a photo be the best it can be.

Any decent editor can handle a color temperature or brightness adjustment. There are undoubtedly things that PS does better than any other editor, but I don't think WB correction is one of them.

[ebiggs1]

Bob
Boston, Massachusetts USA

Bob I think where you are getting hung up is, the camera does not apply any WB or any thing else when you shoot RAW.  It is simply an electronic signal strength of how bright or dark a sceen is.  There is a seperate tag that tells you editor what you set in the camera but it in no way influences the photo unless you want it to.

Of course you can over saturate a photo site or not gine it enough "signal" to recored anything.  This is the DR of the sensor and, in fact, may be out of a range that can be corrected in PS.

Actually PS doesn not do any of this.  It is ACR or Adobe Camera Raw that does.  Then it is opened in PS for further editing.

Here is ACR and where you can apply or not any and all corrections.  This is a "As Shot" which for this photo seems about right.  This approch is the best way for the OP to be successful.  ACR is better then even Canon's own DPP, in my humble opinion of course.

[mgrabow]

The corrections on PS are easier said then done to a aquarium photo.  If the WB is set for AWB or any of the other camera settings the antinic lighting leaves all sorts of ghosting and overblown halos on the photo.  I have not found it easy at all to eliminate these in the raw image using PS.   aomply adjusting the WB/Shift function when shooting eliminates this Ghosting and Halos.

Yes, I know it can be done in PS.   But thats for the PS forum and not here.

Thanks for all the input.  Saving it to the media card will need to do...

[jrhoffman75]

If you are set up for the WB setting save to the new card, or copy the files to each card via your computer.