Cineon white point settings in 16bit

Does anyone know how Adobe (or whoever) arrived at the Converted White Point of 16-bit to 32768 instead of 65535? And more importantly why?

Code is much simpler, therefore faster, if there is "headroom" above the maximum value within the 16-bit quantity you're working on. Calculations with 16-bit variables can overflow and it can easily be detected. If the max value was 65535, you'd need to do the computation in a longer variable in order to deal with overflow.
The reason for 32768 instead of 32767 as the max value is because many algorithms benefit from having an exact center point between min and max values. Since 16-bit format is an integer format, you can't have the value of 16383.5 which would be the center point if the max value was 32767.
There are also some other computational tricks you can play when using 32768 as a max. These tricks improve performance.
And, oh yeah, After Effects does it that way because Photoshop did it that way first. Why rewrite code that already exists and has been tuned for max performance?
(I swore at it the first time I discovered 32768, but I learned better.)
Bob Currier
Synthetic Aperture

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Open the same raw file in PS5 with two different White Balance settings

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Also look at the "Snapshots" feature of Camera Raw itself. It allows you non-destructively to keep multiple sets of settings for a single raw file.
Learning about it far exceeds the scope of what can be done in this particular forum. I would recommend this book as essential reading:
http://www.amazon.com/Real-World-Camera-Adobe-Photoshop/dp/0321713095/ref=sr_1_1?ie=UTF8&q id=1313502199&sr=8-1
Additionally, there's a dedicated Adobe Camera Raw forum:
http://forums.adobe.com/community/cameraraw
Wo Tai Lao Le
我太老了

Setting a White Point and Black Point

I would like to suggest for future versions of lIghtroom to have an ability to set the white point and black points similar to levels and curves in Photoshop. This would be in addition to setting middle grey in the white balance settings currently in Lightroom. I find that the method of using Threshold to find the closest white and black pixels and then using these points to set the black and white points in curves or levels provides a better way to fix a color cast than the methods available in Lightroom.

MB,
There is no real need for Black and White point eyedropper type tools in Lightroom. By holding down the Alt key while changing the Blacks or Exposure sliders the display will show the areas that are being clipped. This is much faster than looking around for the darkest and lightest areas manually. If you just like to click to taste (like using the White balance dropper) then forget the Alt key and just move the sliders until you get the desired look.
Remember that the problem with Photoshop is that there are so many ways to do the same thing that it has become difficult and bloated. Lightroom strives to keep the interface as clear as possible.

Setting black and white points

Dear friends,
I am shooting some pics with a "Whibal like" target card which has a white, black and 18% neutral grey shades.
In Camera Raw I I can easily correct the white balance with the provided eyedropper on the top row by clicking on the grey target.
I cannot find any way to set the black and the white points though and have to resort doing that for EACH picture in Photoshop via a levels or a curves adjustment layers.
It would be great to be able to set those in Bridge/Camera Raw so that I can then copy those settings to other similar shots.
Any ideas ? Thank you
Marco

I am having the same problem, although its now Camera Raw 7 - where can you set the white, mid, and black points in Camera Raw with the eyedropper tool. It seems you have to create a new psd file in Photoshop to do this, which does not make much sense since it is a basic levels adjustment. I am batch editing a bunch of CR2 files, and I just need to select the black, mid and white points on a grayscale that I've shot in the images - is there a way to do this in Camera Raw 7? Thanks!!

CS4 Camera RAW White Point

Setting White Point in Camera RAW 5.7 CS4
I am trying to make pictures out of scanned old slides/negatives which often have colour casts.
Some pictures do not have a suitable white spot for setting the point.
I often find that the "As Shot" or any of the default settings do not look right.
Please what is the best way to set the white point for these ?

Photoshop, or even Elements, would have more options than Lightroom for fixing colors or a color-cast in images that have not been added by the scanner, but is already in the images, themselves, a color cast usually caused by different rates of deterioration of the various pigments in the photo paper or film.
Trying the different Options in the Photoshop Levels command can be helpful.
You can tweak the RGB channels differently in Photoshop Curves.
Elements has a Remove Color Cast command that works for simple cases and is similar to the Auto WB in LR or ACR.
Sometimes you need to duplicate one of the color channels and substitute it for one of the other color channels. For example if the red is entirely faded, then duplicate the blue channel and paste it into the red channel and see how things look, or perhaps use the green channel, instead, depending on the mix of colors in the original. There are techniques for adjusting skintones at the expense of other colors in the image.
There are tutorials for fixing underwater images that would be somewhat applicable to photos heavily faded by prolonged exposure to sunlight or indoor UV sources.
Tweaking the HSL sliders in LR or ACR can be helpful if the image is mostly fixed by prior adjustments.

Webcam White Balance Settings?

Hello,
I just got a Satellite S855 and I had found at some point an option to change the camera's white balance settings to things like "sunny" and "cloudy" but now I cannot seem to find those options anywhere! I can't remember how I accessed them the first time. I have tried to find somr answers and some mention being able to do it through Skype but I sure can't figure out how. I want to record a video and the white balance is terrible. Any clues?

If your webcam is like mine, activate the camera, hover your mouse near the bottom of the picture, click on Settings, click Scene, scroll to the right and you will find Sunny, Cloudy, Rain and Night as well as a few others.
C.B.
C.B.
Toshiba Sat. C75D-B7260 Win 8.1 64 Bit--Toshiba Sat. L775D-S7132 Win 7 HP SP1 64 Bit and Win 10 PRO Technical Preview--Toshiba Sat. L305-S5921 Win Vista SP2 32 Bit

White balance settings always display 5000K 0 Tint

Been searching on this, found a few things, but nothing helpful.
In the past few weeks, it appears that Aperture is no longer interpreting my cameras white balance settings properly. The colors themselves are fine, however, the adjustment applet always shows 5000k with 0 tint. I'm not quite sure when this started, but it's quite frustrating. This appears to be happening on everything newly imported. (I can only verify JPG at the moment, as I'm seeing this on a Canon S95 and 60D, which both don't have RAW support yet in Aperture).
Anyone ever see this happen, or no of a solution? I'm using Aperture 3, latest updates etc. on OS X 10.6.4. My older files all appear fine, it's just these recents, from these two cameras. Unfortunately, I've sold my other gear, and don't have an older cam around to test. Either way, other products, Adobe, seem to be reading things properly.
Thanks for any input.

So all these files are JPEGs?
Note that white balance works very differently with JPEGs and RAW files. There really is no "white balance" information in a JPEG, and you can't adjust them the same way. That's one of the big advantages of RAW files. I suspect once Aperture supports the RAW files for those cameras, then you'll get proper white balance. Until then, with JPEGs you're kinda SOL. It's a bunch more work. But that's the nature of the medium.

Setting white point in LR

I'm almost sure I'm missing something but I cannot find a solution. I'm using LR (currently 2.2) for quite a while (since 1.2) but I simply cannot find an easy, user friedly and predictable way how to set a white point of edited pictures.
In PS, CR, DPP and most other editing SW and RAW processors, there two typical easy tools how to set the white point.
1) a white point picker which (when used) defines a desired tone as white and the relevant SW then redistributes the tones accordingly;
2) in "levels" or "curves" dialog (or their equivalents it is possible to move the "White level" treshold below which the remaining tones are redistributed accordingly - the iterface varies (sometimes it is the border of the histogram or curve diagram that can be moved (DPP), sometimes it is the slider in histogram or curve diagram setting this limit
botw ways generally lead to the same and quite uniform result. I.e. I'm usually able to get almost identical result by setting white point in PS, DPP, CR, .... and other SW by such simple operation when working over identical picture data.
However in LR it is virtually impossible to achieve similar result in LR. No white point picker, no slider enabling setting the white limit, no chance to move borders in the histogram chart. The only available tools for this purpose are
"Exposure" and "Brightness". None of them providing for the desired functionality alone - their combination giving sometimes acceptable but hardly predictable results (definitely not as predictable as achieved e.g. in PS by simple and single move of white limit slider in "level" dialogue or equivalent step in CR.
Do I really miss something important (I hope so) in this respect or is LR completly lacking this (for me really core/basic) functionality present in all other photo and RAW editting SW I know - even from Adobe?
thanks

I agree with the original poster - I find it troublesome to set the white point in an image. In a situation where a traditional (PS, Aperture) levels control would make it convenient to push a particular tone to white, I find myself going back and forth between exposure and the tone curve a fair amount. Another description of what I want, effectively, is a 'recovery' slider that goes up as well as down.
(See end of post for replies to a few specific points.)
An example:
Here is the original image, with its histogram and tone curve - black to middle gray:
I want to push the small hatch/door to white, but that also overexposes my middle grays (I haven't yet touched the tone curve):
So now I go to the tone curve, and pull down both darks and lights:
However, at this point I've lost my whites (they are not quite clipped any more); and probably more importantly, since the tone curve is at the extreme low values, I have little working room or control.
Rather than working together or providing complementary functions, in this case exposure and the tone curve, to me, seem to be fighting; it requires back-and-forth to get the desired effect.
(To be clear, most of the time - that is, when my white point starts out more or less where I want it - being able to drag the histogram and smoothly-transitioned segments of the tone curve is brilliantly easy and useful. It's specifically the exposure control's nonlinear behavior/effect that I dislike, as it makes it difficult to adjust near-white tones.)
Responding to specifics:
> Also, hold the ALT key (David Edwards)
Cool! (However, not a fix for this issue.)
> the controls themselves are not linear (Lee Jay)
> attempts to preserve highlights (Lee Jay)
> the exposure slider is almost exactly equivalent to the white point slider in Photoshop's levels/curves (Joa V. L.)
I think this is the root of the issue, for me - the exposure control is being intelligent in a way to protect hilights, which is counter to my intent. My experience leads me to disagree strongly with Joa's comment (though I would be very happy to discover I was wrong) - my problem is specifically that adjusting exposure up (brightening the image with exposure) affects tones less, the brighter they are.
> I need to decrease the Brightness (Henry_Deer)
> you may need to generate a higher-contrast tone curve and work with that (Lee Jay)
The brightness adjustment seems analogous to my use of the tone curve, though it's an alternate approach I haven't tried. However, both seem to suffer from the 'several rounds' problem.
Edited to reply to a few specific points

Colour Calibration / White Point setting - Is Imac Display really professional quality

I am trying to calibrate my imac 27" using i1 Display2 calibration software. I am trying to set a traget of 6500 using the software but it advises the current is only 5600 and suggests moving the RGB sliders to get this current white point up to my 6500 target. Unfortunatly i have no idea where i find these sliders on my imac. Can anyone advise how i change my current white point to get to the 6500 target?
Also, on the brightness issue, does shades work to reduce my brightness or will it simply interfere with my colour calibration?
Finally, i was going to use my iMac for professional photography. (Mainly on line but some print work required). Honestly, is the iMac display up to the job or should i consider changing
Thanks
Gary

Corbybhy, the glossy screen is the biggest and silliest myth out there. Really.
I have been a professional art director & designer for over 26 years, and by the way, for many years my high end professional CRTS were made of glass (and glossy). Another myth is that the screens cannot be calibrated, and are too bright. Hogwash. I use Spyder3Pro and have had few problems, guessing your device will be the same. Actually, the monitors seem to stay consistant for a heck of a lot longer than the old high end CRTs did. In the old days, most professionals calibrated to 5000k, but these days 6500k is the standard.
The amount of MISINFORMATION that is being spewed always amazes me. If you can keep your lighting consistant and somewhat dim, your life will be easier. Reflections are simply not a major issue, and are also overblown as a issue (by the way, my iMac sits next to a window, I just use shades to dim the ambient light).
I work mostly in print, and produce mostly publications, advertising & marketing materials. I have ZERO issues with my screen matching my proofs. ZERO. I do a huge amount of imaging, retouching & post-processing... all from my 27" iMac.

Establishing White Point and Black Point

Hi,
How do I Establishing a White Point and a Black Point in Lightroom 1.4.1 and especially in Lightroom 2 Bata?
Thank You,
Hersul

The last post by OP might have closed this thread, but given the relative lack of activity on this and LR2 forums (summertime?) - I'll go a little deeper.
i White point
- If your white balance is right from the start, you just use the Exposure slider to set the white point. If not, first set the white balance - that effectively sets a preliminary white point for each channel separately, or, to be more precise, matches the right side of the histogram for each channel - then set the Exposure. So, with the white point you have complete control over the histogram, as well as over each channel.
i Black point
- here the situation is different. You can move the left side of the main (composite?) histogram using the Blacks slider, but there's no means for moving channels separately. In theory, with digital capture, there probably should not be need for this, blacks should be always black, so that's OK, but...
I once had a batch of pics scanned from film. The film was poorly developed so it has some strong brown-magenta cast in the shadows. In Photoshop it was a piece of cake to set the black point by dragging the left ends of each channel to the left edge of the histogram (heck, even Auto Level did a wonderful job). In Lightroom, there's just no way you can correct this, because you can't control the channels separately.

How do I get white balance settings for my Olympus cameras in Aperture?

I have an E-500 and E-510. I was able to figure out from previous posts how to get the white balance listing in the metadata. The information it provides is a 0 or a 1. My sense is that the 0 could represent the auto white balance setting and the 1 any other setting. I have 7 possible settings for white balance on my camera. Is it possible to get specific white balance settings listed in the metadata for my cameras. Thank you for any help.

I can tell you how to display it; I haven't set out to find out what the numbers mean, although that would be pretty easy to do.
Select the Metadata Tab. At the pop-up in the top left select "List-Expanded." Then select from the Gear pop-up in the upper right "Edit List-Expanded." A whole set of options will appear, including White Balance. Check the box and it will be added to the List-Expanded.

Change preferences for Auto black/white point in Camera RAW

Hey guys,
By hold shift and clicking on the slider for whites Camera RAW automatically sets the white point, same goes for the black. However, it always gets pushed to 255 (white).
Is there some way that you can edit this preference?

I don't know, but somebody may know for sure over in the camera raw forum:
https://forums.adobe.com/community/cameraraw

Setting White Points in Camera Raw

When setting white points in Adobe Camera Raw, while holding down Alt (on a PC), are the red marks what I should look for? Because white marks also appear? Which ones are relevant for the white point?

ACR doesn’t work that way. There is an eyedropper for the overall white-balance that you can set by clicking on a relatively bright, neutral area, but there aren’t black and white-point eyedroppers. But, what is clipped black or white is determined by the output colorspace you have set at the bottom and you can get some idea of what will be clipped black and white by turning on the clipping indicators and watching for the areas you’d be eye-droppering on (the black and white patches in your grayscale) to start showing the clipping color overlay for black and white, but any further toning adjustments will move data in and out of what is darker than black and lighter than white so what is clipped for output will change as you fiddle with the various toning sliders.
The reason things are different: In PS, when you set a black-point and white-point in Levels and click Ok, the data below and above those is thrown away and that is the starting point for the next adjustment. In ACR, things are non-destructive and all the adjustments occur simultaneously, rather than sequentially as in PS, and no clipping occurs until you create the output file. This means that the pixels that are darker than your black-point and lighter than your white-point are still there, and can be moved into the black-to-white range if you do further toning adjustments. Having more headroom of the pixels that are outside the black-to-white range is good because you won’t get the posterization or banding that occurs when colors and levels are clipped after each adjustment in PS.
Can you describe what you intend your overall workflow to be on an image: how much adjusting will occur in ACR and how much, if any, might happen in PS, after the image is opened into PS from ACR, or opened from a file saved from ACR? There might be other ways to approach what you’re trying to accomplish.

White Point Presets?

Hello all, I am using the trial version of Aperture2 and so far, I really like running a native pro image editor. I was using Lightroom (still am, mainly at the moment), and it has built in white point presets (daylight, shade, tungsten, etc). Does Aperture have this too? I was looking and I have to admit I haven't looked too thoroughly, but it's not so easy to find if it's there.
Thanks for any help you can offer!

there are no built in white balance presets... but you can create your own ...
here is a post on a blog that i used to make my white balance presets ...
http://blogs.oreilly.com/aperture/2006/11/create-your-own-white-balance-1.html

Using white point for White Balance (instead of gray point)

Dear All,
I am looking to buy Aperture 2.0, but one point annoys me a bit : it seems that we can only use gray point to make a White Balance. I use to use only white points in Photoshop, as my photos of products rarely include gray colors. I take the photos on white background only, and when doing WB with a white point, my product gets nice colors, and more important, appears to "float" on a totally white background.
Also, I do not want to bother with a gray card, as by experience it didn't prove to be as effective.
My question is : is there any means or plug-in to use white point to make a white balance ?
Thanks a lot !
Arn'

Arn,
Hate to break it to you but.... It doesn't matter if you use white or grey as long as the actual color is neutral (no tendency towards blue etc.) what does matter regarding white is to make sure that there is enough color information in all the color channels to make an accurate assessment of the color of the light in the scene.
As there are a million ways to do something in PS I don;t know exactly what you are doing but it sure sounds like you are actually doing a couple of things to the image in one step. In Aperture if I assume you are using the white balance control brick to manipulate white balance that is the only thing that is being changed - nothing else (like the contrast).
RB

Cineon white point settings in 16bit

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