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Would it be possible to add a degree indicator showing the Kevlin temperature of the light source when adjusting the color of the light from warm to cool? Having this feature would allow one to reference the color of light selected against know temperatures for such things as incandescent, outdoors high noon, etc., light sources.
ACDSee Pro 3 Beta - General Discussion
Develop/Submode/White Balance/ Temperature Adjustment
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(10 posts)
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bckoenig@sentex.net
MemberPosted On June 1, 2009 - 05:11 PM (5 months ago) (Permalink to this post) -
Marc Sabatella
ModeratorI'm not clear on what you'r asking here. The actual temperature of the light source is not / cannot be known, but the camera's best guess is recorded as the As Shot white balance, which *is* displayed. Are you just wanting that As Shot vlue to remain visible while you ove the slider, so you don't have to remember it?
Posted On June 1, 2009 - 07:58 PM (5 months ago) (Permalink to this post) -
wotan_odyn
ModeratorI think the point is the currently selected temperature should also be presented in Kelvin (as in 2.5) and not only with -100/+100 scale.
Posted On June 1, 2009 - 09:36 PM (5 months ago) (Permalink to this post) -
bckoenig@sentex.net
MemberI just posted another item on this feature, so part of this is somewhat redundant. The temperature issue is even more complicated than I imagined. First, the Kelvin temperature only appears when processing RAW images. It is not shown when working with JPEG and TIFFs. Why I ask? If moving the slider alters the warm/cool light throughout the entire image, then it shouldn't matter what type of image is being processed. What is needed is the following:
1) When using the temperature slider, I would like to know the temperature change of the light as I alter it from either warm or cool. This feature should be available for processing any type of image.
2) When processing any type of image, I would like added the option of choosing the various fixed color temperature settings (Sunny, Cloudy, etc.) that are presently only available for RAW images.
The "AS SHOT" feature in Beta 3 seems to work somewhat differently than you describe. I believe it indicates the White Balance setting that was selected on the actual camera, and if one isn't selected, it simply says AS SHOT, with no indication of white balance afterwards. In fact, the white balance for some of my photos shows up as "AS SHOT (auto)." And, AS SHOT works the same if I'm shooting in RAW or some other image mode.
Posted On June 3, 2009 - 03:56 AM (5 months ago) (Permalink to this post) -
Marc Sabatella
ModeratorI think the point is the currently selected temperature should also be presented in Kelvin (as in 2.5) and not only with -100/+100 scale.
But it *is* presented in degrees Kelvin, hence my confusion.
At least, it is for RAW, which is the only type of file you could directly set WB for in 2.5. As for why temperature isn't used with JPEG, see Tony's comments in another thread. There is an inherent difference in how RAW and JPEG work in terms of WB. The concept of current color temperture really has no meaning in JPEG. I mean, some program might attempt to make up numbers based on some sort of analysis of the image itself to guess what the light tempoerature might have been, but that's just a guess, and a very bad one at that. Consider: if AWB works "perfectly', there would *no difference whatsoever* between JPEG images taken under tungsten light or overcast skies. oth would show up completely neutral. Whereas for RAW, the actual imag data would be uncorrected for WB, and the WB setting used by the camera is encoded within the RAW file.
Posted On June 4, 2009 - 04:27 PM (5 months ago) (Permalink to this post) -
Marc Sabatella
Moderatorbckoenig@sentex.net said:
The "AS SHOT" feature in Beta 3 seems to work somewhat differently than you describe. I believe it indicates the White Balance setting that was selected on the actual camera, and if one isn't selected, it simply says AS SHOT, with no indication of white balance afterwards.
If you're talking about JPEG, see my comments above. Reporting color temperature does not make sense for JPEG as it does for RAW, due the different nature of the formats (JPEGs already have the WB "cooked" into the data, not separated out as in RAW). To extend the cooking analogy, displaying and controlling WB temperature for RAW is like controlling the amount of sugar to put into a cake *before* you bake it. It's obviously simple to see exactly how much sugar you're putting in, and change that before baking. Once the cake is baked, it's pretty impossible to tell from the finished product how much sugar was present, much less change it after the fact. Sure, you can add more sugar, or add salt or something else to try counteract the effect pf the sugar thatwas already added, but there would be no way to display the results in terms of how much sugar there is total if you don't know how much sugar was there in the firstpalce- and that's pretty much the way it is for JPEG.
In fact, the white balance for some of my photos shows up as "AS SHOT (auto)."
Mine do too on in the drop down, but on the temperature slider, it should report the actual temperature in degree Kelvin, at least for RAW. The image I'm looking at right now says "As Shot (Auto)" on the drop down, but "Temperature = 3715 K" right below that. Similarly for the rest of my RAW files. Are you seeing something different for your RAW files?
Posted On June 4, 2009 - 04:36 PM (5 months ago) (Permalink to this post) -
sales@scalesusa.com
MemberShowing a Temperature in Kelvin is pretty much worthless. The image should be adjusted so that it looks natural or however you want it to look. Setting a slider to a arbitrary Kelvin temperature will not do this. This is why the idea doesn't appear in lightroom, it just doesn't do what some think it will.
Posted On June 4, 2009 - 05:00 PM (5 months ago) (Permalink to this post) -
bckoenig@sentex.net
MemberThanks to all who have responded to my post. It was educational for me. Last night I did some shooting indoors in the dark with only an Incandescent light source. I shot once in Raw, in JPEG, & in TIFF, with the White Balance set at Incandescent. I shot again with the White Balance set at Daylight/Outdoors. I then compared all the images in Pro 3. Some interesting results surfaced. I managed to take the RAW "temperature number (inside the box to right) and translfer it to the TIFF and JPEG photos. Yes, they were not "right on", but I did managed to adjust them to "my liking".
All this leads me to this question and I am only asking this to those at ACDSee:
When I open a JPEG or TIFF photo, the TEMPERATURE slider always goes to ZERO. In the "white balance" box above the TEMPERATURE slider, I might also find information like "INCANDESCENT," "CLOUDY", etc.
What does ZERO "represent" or "indicate"? Since the Scale Label says it represents TEMPERATURE, then what does the TEMPERATURE scale represent when it "ZEROs OUT in these various white balance instances? Midway between +100 and -100 represents what?
Now the harder part, as I move the slider to the right or left, is the TEMPERATURE changing? If yes, How is it changing? Some type of mathmatical formula was designed for the slider. What is it?
************* All of my posting might seem a little weird, but I guess I'm a bit weird. I taught stage lighting design for some 35 years, which involved working with hundreds of color filters and various light sources (incandescent, carbon arc, quartz, etc.). One of the fun experiments I would undertake with the students was to record a dimmer LEVEL setting (1 to 100), that resulted in a particular color of "white light" on stage. Based on the color seen and the level setting, the "trick" was to determine if the dimmer used was a "resistance dimmer," an "auto-transformer," a "tube-amplifier", or an "SCR dimmer." All of these dimmers would produce a different color of light at a particular setting. The LEVEL SETTING was important as all of these types of dimmers existed then and knowing their individual "Curve" was important. (At least three of them still exist today.) So, what does this all mean? --- I think there is a problem with using the label TEMPERATURE when working with TIFFs and JPEGs. I may be wrong, but after working with the TEMPERATURE slider I believe it functions more like an "old fashioned" "warm" or "cool" photographic filter.
Posted On June 5, 2009 - 01:56 AM (5 months ago) (Permalink to this post) -
Marc Sabatella
Moderatorbckoenig@sentex.net said:
When I open a JPEG or TIFF photo, the TEMPERATURE slider always goes to ZERO. In the "white balance" box above the TEMPERATURE slider, I might also find information like "INCANDESCENT," "CLOUDY", etc.
What does ZERO "represent" or "indicate"?
Indicates you haven't changed the color from whatever was "cooked" into JPEG. It's impossible to know what WB value was actually used in the generation of that JPEG - such info is simply not recorded in any standard way for JPEG. So all ACDSee can tell is you how much you are *changing* this unknown value.
Since the Scale Label says it represents TEMPERATURE, then what does the TEMPERATURE scale represent when it "ZEROs OUT in these various white balance instances? Midway between +100 and -100 represents what?
No idea, but I'm guess nothing, really - just the number of steps ACDSee happens to give you. Kind of like if someone asked you rate something on a scale from 1 to 10 and you asked, what does those numbers "mean"?
Now the harder part, as I move the slider to the right or left, is the TEMPERATURE changing?
Depends on what you mean by temperature. The actual light used in taking the picture had a temperature, but of course you can't go back in time and change that just by moving a slider in ACDSee. Even for RAW, when an actual temperature is recorder, what you are really soing is not changing the temperatue of the light to the reported value, but rather the *opposite* of that - you are *correcting* the picture *as if* the light had been the reported temperature. So when it repots, say, 4000K for temperature, that means it is assuming the light was 4000K and is now trying to correc thte picture to look neutral. If you change move the slider left to a lower temperature, that represents a more red/yellow/orange color of light, but the picture doesn't become more red - it becomes *less* red. That's because the slider is your way of telling the camera, "let's pretend the color of the light really was X, and I want you to remove tht color cast". So you are telling the camera the light was actually a lower temperature than it really is - that it is really orange instead of of fairly neutral. And then ACDSee tries to compensate by *removing* this orange color cast, resulting in a bluer picture.
This behavior, BTW, is not unique to ACDSee - it's the way image processing orograms work.
The numbers in the box don't represnt anything in particular - they are just "clicks" in whatever scale ACDSee uses. The only number that has meaning is the temperature numebr displayed for RAW files, and that is the actual color temperate of the color cast ACDSee is attempting to remove.
So, what does this all mean? --- I think there is a problem with using the label TEMPERATURE when working with TIFFs and JPEGs. I may be wrong, but after working with the TEMPERATURE slider I believe it functions more like an "old fashioned" "warm" or "cool" photographic filter.
Perhaps so, but again, it's really standard practice in the photographic world. People familiar with other image processing programs would have a fit if ACDSee were to work differently from the rest of the world for no good reason.
Posted On June 5, 2009 - 05:00 AM (5 months ago) (Permalink to this post) -
k h
Focus Groupbc, here are some good articles on color temperature and white balance...
http://en.wikipedia.org/wiki/Color_temperature
http://www.cambridgeincolour.com/tutorials/white-balance.htm
Posted On June 5, 2009 - 07:18 AM (5 months ago) (Permalink to this post)
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