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Old Mar 10, 2005, 12:14 PM   #1
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Hello Digital Experts,

I finally entered the digital world and bought a new D70 camera. So far I am really enjoying it. However, I am a bit confused in regards to adjustments on the camera vs Adobe Photoshop. I am pretty new to both.

What I have noticed that after I have taken some pictures I use my computer to make some adjustments to the digital image. The program I use is Adobe Photo Shop. In this program, I use the LEVEL adjustments to correct the picture usually lightening the image. What I am trying to understand is:

1. Is this LEVEL adjustment the same thing as what the camera calls "White Balance"?

if not.

2. What is the difference between these two and is it better to do it in once place rather than the other.

Any help would be appreciated.

Thanks,

Pete

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Old Mar 10, 2005, 2:58 PM   #2
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White balance is not the same as photoshop levels. White balance is adjusting the sensitivity of the sensor to suit the available lighting. The most obvious example you can try is take a photo indoors without flash and lit by a normal bulb. If you set the camera white balance to auto the photo will come out withvery orange tones. If you take the same shot setting the white balance on the camera to the bulb symbol the colours will be much more natural looking.

style="BACKGROUND-COLOR: #000000"If you are using Photoshop CS you can adjust the white balance of RAW files while reading them in. With this you can select any of the camera presets or adjust the temperature & tint to get the best colour rendition.

style="BACKGROUND-COLOR: #000000"A useful feature on the D70 is the preset white balance which allows you to take a reading from a white or grey card under the conditions you plan to take your shot. This is useful in unusual lighting conditions that the presets don't cater for.

style="BACKGROUND-COLOR: #000000"I always shoot RAW and try to set the white balance correctly on the camera and if that fails use the Photoshop RAW converter to correct the white balance when processing.

style="BACKGROUND-COLOR: #000000"I use levels after I've loaded the file to adjust the tonal range of the photo but only after correcting white balance.
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Old Mar 11, 2005, 2:57 AM   #3
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Hi, Nagasaki.

Are you sure the white balance deal with the raw files?

As far as I know, the white balance only is applied to jpg files. As for the RAWs - they just store the white balance information, and use it when opening the RAW file. But the RAW file itself is "raw" indeed, and is influensed by ISO settings only.
Am I right?

Dear Peterob, first of all:
do shot JPG files, or RAW files?
Then, if you use the RAW files, what program do you use for opening them, as Photoshop itself can not open the RAW files, it needs a plugin for that, or you can open it with any Nikon program, which are usually supplied with a camera on a CD.
(The Nikons RAW files have an extention NEF)

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Old Mar 11, 2005, 4:10 AM   #4
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Yes I'm sure about the white balance and RAW files. It stores the white balance setting you shot with and applies this. What is different between RAW and JPG files is that you can change the white balance in post processing on the computer. For example I took some shots under available light using a preset white balance. I then took some more shots with flash and without changing the white balance setting. When I looked at the shots on the computer later the available light shots looked fine but the colours in the flash photos were wrong. I changed the setiing on white balance to flash and bingo perfect colours.

As a fairly extreme example I'm attaching an underwater shot.

As shot colour temperature 6800 tint +1
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Old Mar 11, 2005, 4:26 AM   #5
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And corrected Colour temperature 9000 tint +150

Shot as RAW only adjustment is white balance, resizing and unsharp mask. Same resizing and unsharp masking applied to both versions.


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Old Mar 11, 2005, 6:23 AM   #6
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A great shot!!!


As for WB,
You wrote White balance is adjusting the sensitivity of the sensor

I'was always thinking that only ISO settings adjust the sensor sensitivity.
WB, as I understand it 100% software issue. In case of JPG - camera process the raw image and apply WB , Sharpening, Tone compensation, saturation, etc... then convert it to JPG file.

In case of RAW files, WB informatin is just written in file as shooting info, no changes to RAW picture data. When you open the RAW file on computer is usually processed for viewing according to WB settings stored in shooting info. In Nikon Editor, for example, by default, RAW is processed by WB setting stored in RAW file, but you can choose "NO" WB correction and then you'll get the RAW file, as it was recorded by sensor.

That is as I understand the process...
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Old Mar 11, 2005, 8:09 AM   #7
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You are right my explanation was probably not the best. As you say adjusting the ISO adjusts the sensitivity of the sensor. With white balance it is I think just software and it's adjusting the mix of the Red Green Blue elements recorded to restore the correct colour balance. I've not seen a setting of no white balance in the software I'm using.
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Old Mar 11, 2005, 9:44 AM   #8
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Hello and thanks a lot for the reply,

It sounds like I am getting over my head as a newby but I would like to see if I understand what has been said. Please tell me if I am close or way off track.

White Balance: This is the camera's adustment that portrays colors in a certain manner. By adjusting the white balance you will change how your camera interpretts these colors. Since lighting (natural, flash, and floresence) affets how the camera reads the colors, the camera can be adjusted to correct these to the users liking?

Photoshop Levels: I have attached a screen capture of a photoshop screen. Often indoors, I find that I have to adjust levels on the pictures since they seem to be coming out darker than I want. Since I am new to this camera most of my pictures have been on one of the auotmatic modes. So my two questions are:

1. In photoshop adjusting levels, Imove the triangle on the right (one of three adjustment points) toward the left, I am lightening the picture but what am I doing to the image? I know I can make adjustments to brightness and contrast but this "LEVEL" tool seems to work the best. I guess I am just to dumb to know exactly what I am doing? Any ideas?

2. Since my images indoors seem on the dark side, what recommendaitons do you have on what adjustments should I make? Can I leave it in program and change ISO or what settings might be best to adjust.

3. You talk about Nikon Software for Raw images? Do you recommend buying this or can I just get download an addon for Photoshop?

Thanks for any help.

Regards,

Pete

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Old Mar 11, 2005, 1:27 PM   #9
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Your explanation of white balance is spot on.

Your example of the levels tool is a very good one. You can see by the histogram that the picture is underexposed because it is shifted towards the left and there is very little data at the white end (the right). What the levels tool allows you to do is shift the histogram so that by moving the right hand pointer towards the left you are resetiing the white point. Usually you'll set this to the most right hand end of the actual data. the data is then redistributed over the scale and the picture will appear lighter. The left hand arrow can be used to set the black point in the same way if there is no true black in the picture there will be no data at the left hand end of the histogram. Shifting the lefthand arrow toward the right resets the black point and will improve contrast in a picture. The middle pointer sets the mid point of the image and can be used to lighten or darken the image. In most cases the Levels tool is a far better tool than the brightness and contrast tool as it gives you more control over the final result.

With all that said you could use exposure compensation on the camera to increse the exposure of the original shot. If you use RAW and have installed picture project Photoshop should be able to open the RAW files and provides an exposure compensation slider that is very good for lightening under exposed shots. If you have Photoshop CS and download the updated RAW converter that is even better than the supplied Nikon converter.

Finally I'd ditch Picture Project and download the free Nikon View 6.2 from the Nikon website. It's a far better piece of software that the picture project program supplied with the camera.
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Old Mar 12, 2005, 2:52 AM   #10
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1. The levels are much more powerful, than contrast and brightness. The most advanced tool is "curves", but they need a lot of expearence to work with.

As for levels -- keep in mind -- in most cases you can move the outermost marks to cut off the "empty" parts of histogram. this will increase the contrast. But if you cut a pare of curve you can lost some information.

For example: On your screen capture, the white mark is a little bit too fare to the left. This small part of histogram (to the right of white mark) is responsible for the light tones. If you cut them, as we see on your histogram, you may have white spots on faces.

2. If you want to have a really good indoor pictures you'll need either a good external flash, or a good lenses with a wide apertura (or both!)

Of course the most easy way is to increase the ISO - but on levels above 400 you'll notice that the noise is increasing and on 800-1600 levels you'll need a good noise reduction program.

On you snap shot you can see, that the curve is moved to the left (dark) part of histogram. In most cases this is not good. You just "not use" that "empty" patr of histogram, which means that you reduse the quality of your shot. On the other side if your histogram is wider than tha scale you will loose some information in lights or in dark parts of picture.

3. The Nikon View 6.2 is a good tool. When installed, Photoshop, usually use it's RAW convertor for opening NEF files.


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