Paint Shop Levels

The Paint Shop Levels adjustment in the digital darkroom is somewhat analogous to increasing or decreasing the amount of time photo paper is exposed in the traditional darkroom. With most images the adjustment will also improve the contrast.

The intent of the adjustment is to expand the tonal range of an image so that it covers the full lightness range from 0 on the left (the shadow area) all the way up to 255 on the right (the highlight area).

The tonal range is seen in the image's Histogram and here is one that covers the full range ...

Ideally the best image will have pixels at each level from 0 to 255 in a shape somewhat similar to this one. The perfect histogram will be a nice bell curve shape but this one is pretty good.

Analyzing An Image

In this tutorial I will be using this image of Libby (one of my two Miniature Bull Terriers) with her favorite ball during a bit of down time.


Libby	Histogram

I like the picture but it is a bit dark. This is confirmed in the histogram. Most of the pixels in the image are grouped from the high shadows to the low mid tones, hence the dark image.

The right end of the histogram is the highlight area and remember that ideally the full tonal range will extend right up to 255. In this image the first pixel in the highlight area is at position 211 so 44 levels of lightness are missing and that amount of missing information will have an effect on the image.

If you feel so inclined you can find this out for yourself with your image. Move your cursor over one end of the horizontal line, left click and hold and then drag the cursor along the line.

The information on the right side of the histogram will change according to the cursor position.

Back to the image - if I want my shot of Libby to cover the full tonal range then some adjustment is required. That adjustment is the Paint Shop Levels adjustment.

Paint Shop Levels

You have two choices to do a levels adjustment - directly on the image or with a levels adjustment layer.

Use the adjustment layer - here it is ...

You can click on one of the buttons on the right side of the dialogue to make adjustments ...

Contrast - automatically adjusts the contrast of the photo.
Color - automatically adjust the photo's color balance.
Levels - automatically adjust both the contrast and the color.

You can also select one of the colordroppers and click on the image letting Paint Shop Pro make the decisions for you but that is somewhat hit and miss unless you press the ALT key and work in the Before pane (the one on the left) of the Preview window.

What this does is automatically determine the white, black or gray point. As you move the cursor around in the Before pane with the Alt key pressed through the light, dark and mid-tone areas, the appropriate colordropper is activated and you simply click to set the point.

In this screen shot the cursor is hovering over an orange area which is a mid-tone.

The left colordropper is clicked on a black area.
The right colordropper is clicked on a white area.
The middle colordropper is clicked on a neutral gray area.

There are three little diamonds below the levels histogram and this is what they do ...

The black (left) one adjusts the shadows.
The white (right) one adjusts the highlights.
The gray one (middle) adjusts the mid tones.

With the Libby image there is some highlight information missing (remember - the first pixel in the highlight area is at position 211 so 44 are missing).

The way to correct this is to put your cursor over the highlight diamond (the one on the right), left click and drag it to where the histogram starts to rise. It doesn't have to be at 211 - make sure that Preview is checked and watch the image.

If you wish to be exact then either watch the little box on the right below the highlight diamond or just double click in the little box and enter the number.

I just moved the diamond to 211 and this is how it looks ...

And this is how the image of Libby looks now ...

Now that is much better and Paint Shop levels is such an easy adjustment to make - here is the new histogram (the new adjustment layer has to be merged with the background to see the resulting histogram) ...

paint shop levels histogram

As you can see the highlight area has been moved up to the right side at position 255.

The major part of the histogram is still in the high shadow/low mid tone area but that's OK. It's part of the charm of this image.

If I wanted to lighten the ground around my little girl then I could move the mid-tone slider to the left after making the highlight adjustment but - nah. I like it the way it is.

I bet you want to see it anyway.


Both the Highlight and Mid-Tone Adjusted	The Histogram

The background is now rather bland and that is apparent in the histogram because the curve does not extend all the way to the shadow end anymore. Every image is different and the second adjustment to the Paint Shop Levels may cause your image to pop beautifully.

The first adjustment (highlights only) is the only one that was needed with this picture.

Examples

Church Spire

	This is not a bad image and could probably stand on it's own as it is.
	The Histogram shows that information is missing in the highlight area
	The Highlight slider was moved up to 218 which brightened the image. This adjustment caused some of the highlights on the front of the steeple to become far too light so the mid-tone slider (the one in the middle) was moved toward the highlight area (just a tad) to restore those areas.
	The adjusted image.
	The final Histogram. Now the graph extends from the Shadows on the left to the Highlights on the right.

Dog Walking Park

	I took this picture in a local dog park. What I saw through my viewfinder and what downloaded to my computer were two completely different things. The scene was much more colorful with more contrast. This is flat with muted colors.
	The histogram is missing a lot of information in the shadow area.
	The Shadow slider was moved from 0 up to 80 to improve the shadows.
	Now that's more like what I saw at the dog park! Paint Shop levels did an amazing job with this image.
	The histogram after the Levels adjustment now stretches the full width of the scale. Look at the left end of the histogram - see that large spike there? That's called clipping and it means the adjustment caused some part of the image to be totally black with no detail whatsoever. This really isn't desirable so I am pretending I did it to demonstrate clipping.

Swan

	This is another one of those images that looked wonderful when you're looking through the viewfinder but left a lot to be desired when it was downloaded. .
	The histogram is missing a lot of information at the shadow end as well as some information in the highlights. At least 78 levels of lightness are missing in the image - almost 25%!
	The Shadow slider was moved from 0 up to 62 to improve the shadows and the Highlight slider was moved to 239 to spark up the highlights.
	There is more drama in this image. The Swan's neck is kind of a muddy brown from sticking it's head in the water. This would be a good place to do a soft light layer dodge and burn.
	The final histogram now stretches from the shadows to the highlights.

Church Door

	Does the Paint Shop Levels adjustment layer work with black and white images? It does.
	The histogram is missing a lot of information in the highlight area.
	The Highlight slider was adjusted to the left to position 216 and then the mid-tone slider was moved to the right to perk up the mid-tones. Really, the numbers are not important unless, of course, they are important to you.
	The bricks have more life and the archway is no longer flat and bland.
	Now this is an interesting histogram! The vertical yellow lines are realy holes in the histogram. When information that originally spanned 80% of the range from 0 to 255 (about 205 levels of lightness) is stretched to cover the full range then something has to give. Some levels of lightness are not included in the image now but they are impossible to see.

A Difficult Image

Sometimes it's embarassing to show one of my really crummy images. This is one of them ...

And here is the histogram ...

paint shop levels historgram

After our journey thorugh Paint Shop Levels do you have any idea what's wrong with this image (other than you really can't see what it is)?

In my defence it was getting dark and it was raining.

Anyway - there is a very tall spike at the left side of the histogram which says the blacks (aka shadows) are clipped and there are virtually no highlights other than the headlights and reflections on the wet pavement.

There are a few different ways to work with a difficult image like this ...

Delete it.
Blend Modes.
Paint Shop Levels.

You won't learn anything if you delete it so that is not a very good option and maybe there is a photographic gem hiding under all that darkness!

Blend Modes are great and will handle this quite nicely. Youll find Blend Modes here.

This is a Paint Shop Levels tutorials so let's work with them.

The procedure is simple - create a new Levels Adjustment Layer and drag the Highight slider to the left until you come to the place where the histogram starts to rise. With this image it is at that first little bump around position 73 and the mid-point slider was moved even further down to 17.

Remember the lightness range spans 256 levels (0 to 255) and this image only covers about 73 of them!

Here is the image after the adjustment ...

Now that made a huge difference, didn't it?

paint shop levels post adjustment histogram

The new histogram of the merged layers shows that the lighness levels extend all the way from 0 on the left to 255 on the right.

There are, however, some gaping holes in the shadow end and there is still some clipping in the shadows.

The mid-tones that didn't exist in the original, are well represented in the adjusted image.

I agree that while the Paint Shop levels did bring out the image it's still not perfect. It's nice to know that you can rescue an important image with Paint Shop levels if your really need to.

Summary

When you open any image check out the histogram to see what you have. If there is any information missing create a levels adjustment layer and make your adjustments. When you like the results click OK and merge the layer down.

This will give you a tonal range that spans the full brightness range (the perfect starting point) so now you can move ahead with whatever other adjustments you need to make.