CI Photocommunity

Register a free account now!

If you are registered, you get access to the members only section, can participate in the buy & sell second hand forum and last but not least you can reserve your preferred username before someone else takes it.

RAW Processing and Image Saving

laurence2

Well-Known Member
I thought I had read somewhere that when processing RAW in the Sigma proprietary software, that if you change the White Balance on a RAW image, that it automatically defaults to changing the original RAW image?

If so, what do you do to get around that, if there is actually a way in the software?

Of course, I could always Save As and put the original RAW in its own folder, but that seems like extra space and an extra step.

Any suggestions would be appreciated!

Laurence
 

foveonfan

Well-Known Member
Laurence, any change in the WB setting manifests itself as additional information in the RAW data. However, as I understand it, that's not the end of the matter as you can change it back and forth at will as the original data always retains its integrity.

Sincere regards, Jim Roelofs
 

laurence2

Well-Known Member
Good! I was rather puzzled by what I read (wish I could find the passage). I didn't really WANT to have to take too many extra steps to save the original RAW.

Thank you for the tip! It is appreciated.

Laurence (or Larry)
 

Guest .

Banned
Laurence, any change in the WB setting manifests itself as additional information in the RAW data. However, as I understand it, that's not the end of the matter as you can change it back and forth at will as the original data always retains its integrity.

Sincere regards, Jim Roelofs

Perfectly right! The WB-record is nothing but an additional information which is added to the RAW-data with each shot! (This is different when using JPG-mode, where colour-info is really (lossy) manipulated.

Going RAW, you can adjust your WB anytime on your computer. Therefore all these endless "Which WB-setting is best and when...??" discussions are awkward.

In most of the cases the SIGMAs do quite well with AWB-mode. In the few instances in which the cam gets it wrong, because a camera neither can think nor can it assess the scene, you can tune things later on your computer.

see you with nice pictures

Klaus
 

laurence2

Well-Known Member
Perfectly right! The WB-record is nothing but an additional information which is added to the RAW-data with each shot! (This is different when using JPG-mode, where colour-info is really (lossy) manipulated.

Going RAW, you can adjust your WB anytime on your computer. Therefore all these endless "Which WB-setting is best and when...??" discussions are awkward.

In most of the cases the SIGMAs do quite well with AWB-mode. In the few instances in which the cam gets it wrong, because a camera neither can think nor can it assess the scene, you can tune things later on your computer.

see you with nice pictures

Klaus

This is invaluable information. Specifically because it is meted out in layman's terms. Thanks so much, Klaus.
 

foveonfan

Well-Known Member
This is invaluable information. Specifically because it is meted out in layman's terms. Thanks so much, Klaus.

Another thing, Laurence, is that once you open the file in SPP, you will notice that one of the options listed in the drop down menu is "Original".

Sincere regards, Jim R
 

laurence2

Well-Known Member
Another thing, Laurence, is that once you open the file in SPP, you will notice that one of the options listed in the drop down menu is "Original".

Sincere regards, Jim R

I see. I would assume that would take you back to the original untouched RAW file, sort of like "revert" in Photoshop?

Best,
Laurence
 

kakou

Active Member
Perfectly right! The WB-record is nothing but an additional information which is added to the RAW-data with each shot! (This is different when using JPG-mode, where colour-info is really (lossy) manipulated.

Going RAW, you can adjust your WB anytime on your computer. Therefore all these endless "Which WB-setting is best and when...??" discussions are awkward.

In most of the cases the SIGMAs do quite well with AWB-mode. In the few instances in which the cam gets it wrong, because a camera neither can think nor can it assess the scene, you can tune things later on your computer.

With most cameras this is true, but in the case of Sigma, it's not.

Although there is a white balance tag in the file, the X3F data itself is slightly different depending on the camera's white balance setting. You can see this by simply looking at the size of the raw file. I recall it being around 10% difference which is a lot more than just a different WB tag. X3F files are compressed so their size does vary, but if the only difference is a tag, the sizes should be the same (or very close to it).

Another way to check is take a series of photos with various white balance settings on the camera, such as sunlight, shade, incandescent, auto and custom. Then open the raw images and try to match their white balance. What i've found is that you can generally get close but never exactly the same, and sometimes it's even hard to get close.

If it were just a tag, you would be able to match it, whether you white balanced before or after.
 

Guest .

Banned
Hmmmm,

that WB-info is just an additional tag to the RAW-data is widely accepted general knowledge along all pieces of information I ever got ... (which does not mean that I know everything!);)

Anyway, the difference in file size between different shots cannot prove your finding above.

Just try to just do two different shots with completely unchanged camera settings??! They most probably will differ in file sizes. Just fail perfect focus adjustment and your file loses details and file size.

Beyond this ... there are such an awful lot of photo-scenes that simply do not allow any kind of sensible WB settings .... have a look:

-DAWN-.jpg

Which WB-setting would you go for?! In my humble opinion, there is none.

Even later at your computer there is nothing neutral grey in the pic to have it adjusted. You simply have to take a decision ... I took the one above!!

See you with nice pictures

Klaus
 

kakou

Active Member
Anyway, the difference in file size between different shots cannot prove your finding above.
True, but it suggests that there's more than just the tag that's different. You could dump the raw data and analyze it but that's even more work. :)

Try a couple photos at different white balances (especially taken in indoor lighting) and then try to match the colours.

If it's just a tag it should be easy...

View attachment 1203

Which WB-setting would you go for?! In my humble opinion, there is none.

Even later at your computer there is nothing neutral grey in the pic to have it adjusted. You simply have to take a decision ... I took the one above!!

Whatever you picked, it's the right setting. The photo looks nice and that's really all that matters.
 

laurence2

Well-Known Member
In a way, it's NICE that there is a variation between white balance settings that clearly affects the image! It raises the possibilities of getting "what you want"! In this case, Klaus, the image is stunning. Beautiful gradations of color, and of course a greatly balanced image in its composition.
 
Top