PowerRetouche photo editing software - Our photoshop plugins are for most photo software and graphic software like Fireworks, Corel Draw, PaintShopPro and others
   
 

The left side is the original. Right side is filtered with the plugin. Notice all values and hues of the color are preserved. HDR - High Dynamic Range Image Compression - A Photoshop Plugin

Brighten dark areas and darken lights in high contrast photos. Use it for shadow illumination. Make you photos match what the eye sees in nature by revealing what's hidden in dark areas. Shift the images entire dynamic range or stretch the range to perfect white and black point. Our method does not create halos!

photo software, photo restoration, photo editing, image editing, photoshop plugins, digital photo software, image editor, plugins, photo editing software, plugin, tutorial, tutorials, photoshop tutorials, free demo, photo retouching, picture editing, photoshop plugin, graphic software, graphic design Power Retouche Photoshop plug-ins are also for Paint Shop Pro, Corel Draw, Illustrator, Fireworks and other graphic software or photo software for photo editing, restoration and retouching (Mac & Win) see list

Introduction to the PowerRetouche Photoshop plugin: Brightness Editor
 

Dynamic Range Compressor plugin - Tutorial

The plugins are for both OSX and Classic
The plugins are for all versions of windows

Benefits
of the plugin

Illumine shadows without overexposing lights Illumine shadows without overexposing lights.
Darken lights without darkening shadows. Darken lights without darkening shadows.
Reduce contrast by reducing the dynamic range. Reduce contrast by reducing the dynamic range.
Master all aspects of dynamic range like offset and white- and blackpoint stretching. Master all aspects of dynamic range like offset and white- and blackpoint stretching.

The Dynamic Range Compression plugin works with these image modes (Win and Mac):
8 & 16 bit / channel: RGB, Grayscale, Duotone, Lab, CMYK, Multichannel.

Tutorial

Tutorial as pdf

Buy plug-ins now

Products overview

Brightness Editor
controls

Click to see the brightness editor plugin at full sizeThis is the Dynamic Range plug-ins control panel. Click on the photo or the links to the right to see the plugin at full size. The filter has four groups of controls:

1. Range Compression - darks and lights
2. Graduated effect
3. Range adjustment - offset and black point
4. Overall effect and saturation

See Windows plugin

See Mac plugin

Download Win plug-ins

Download Mac plug-ins

Download tutorials

Example - The left image has its high dynamic range compressed in three degrees

Original photo
slight compression
adequate compression
high compression

The Dynamic range Compression plugin is indispensable for making high contrast photos look like what the scene really looked like when you took the picture. Original is leftmost.

How the plugin filters the photo PowerRetouche Photoshop plugins tutorial
   





 

What is HDR - High Dynamic Range - and why is it a problem?

High Dynamic Range (HDR) and its problems

A photo's dynamic range is the pictures span from its darkest value to its brightest value. If the darkest value is black and the brightest white, then the dynamic range is fully utilized. Most pictures don't cover the entire range and are offset from either white (most common) or black or perhaps both. This is not necessarily a problem as it can be a way to control the photos expressive power.

What is a problem, however, is the annoying fact that the camera or scanner - or the monitor - is not as sensitive to the entire dynamic range as the human vision is. In other words the human vision has a higher dynamic range. In a scene where the eye will perceive details in both the light and dark areas at the same time, the camera or scanner will only be able to capture one end while rendering the other as an underexposed or overexposed mass. With our filter you can correct that and restore the original impression.

 

What is High Dynamic Range Compression?

High Dynamic Range compression

... is also called High Dynamic Range expansion

"High dynamic range compression" is also sometimes called "high dynamic range enhancement", "high dynamic range expansion" or "high dynamic range extension" This is because if you want to expand the visible range, you have to compress the image data.

As you can see in the large example just below, the camera is not as sensitive to small variations in the dark range as the eye is, so we have to compress the dark values in order to reveal what the photo hides in the shades. Fortunately the camera is not blind, but does capture much information in the dark areas of the photo, so we can reconstruct what the eye perceived.

Since the photo already covers the entire dynamic range, we can't improve the image by overall brightening - that would overexpose the lights. Proper dynamic range compression stays within the photos given dynamic range and will compress either the darks or the lights. In this case we have made the given dark range cover a much wider dynamic range and have thus restored the original impression of the scene.

 

Example of full filter use when compressing shadows

High dynamic range compression of shadows


Original photo


Shadows% 100
Compr. factor 90
Offset 32 (until white alert is just off)
Black Point 8 (until black alert is just off)
Saturation% 60

 

Example of full filter use when compressing highlights also

High dynamic range compression of highlights also

You will find that most of the discussions about correcting HDR, high dynamic range, images, is concerned with how to compress the shadows and expand visibility into the dark areas. However, images can improve considerably by compressing the highlight range.


Original photo


Shadows% 90
Compr. factor 85
Highlights% 20
Compr. factor 85
Offset -90
Saturation% 60

In this case we lowered the offset a bit below black alert in order to darken the lights as much as possible before compression.

 

The Controls

Range compression

 



Range adjustment





Overall effect

First group lets you compress either shadows or hightlights.

 

 

Second group lets you change the outer limits of the density range. Here you can make the lights brighter and the darks darker. In other words you can move the histogram up or down (offset) or expand the histogram in either direction.



Third group lets you adjust saturation and also reduce the effect by mixing with the original.

 

Graduated effect

 

These controls are common for many of the Power Retouche plug-ins. Using graduated effect will cause the filter to apply it's filtering at full strength in one side of the image and then fade the effect out towards the other side. You can change direction by right clicking the preview. Midpoint will shift the balance between how large an area will be filtered at full strength and how much will have a faded out effect. Contrast will change the accelleration and spread of the fade-out.

In this example we applied a graduated effect towards the bottom, setting midpoint to the edge of the gray clouds. This retouch brought light into the underexposed foreground, bringing it forward, without altering the sunset.

 

Examples of what the controls do

 

Shadows %

This determines the amount of high dynamic range compression - at a given compression factor.

The example was compressed 100% at factor 85.


Original photo


Sh. 100% factor 85

 

Compression Factor

This determines the power of the high dynamic range compression.

Settings between 80 and 90 are normal.
Above 92 are considered high.
Above 95 rarely have any use except when you set the overall effect to less than 100.

The example is filtered the same as above (100%) but now at factor 90.


Sh. 100% factor 90

 

Highlights %

Color problem when compressing highlights

In the same way as with the shadows, you can compress the lights. This is less common a need, so by default it is set to 0 (off).

Here the mountains are correctly exposed with the result that the sky is overexposed and the mood lost.

The filtered example was highlight compressed 100% at factor 85.

As you can see better results are acquired by compressing the shadows. This is because more color information is retained in the underexposed areas than in the overexposed - so when compressing overexposed areas the lights tend towards gray rather than a hue.


Original photo


HL 100% factor 85

 

 

Other Controls

 

Offset

 

 


Black Alert

White Alert

This slider offsets the entire range from either black or white. In other words if you image ranges from dark gray to bright gray, you can change its black offset so the image ranges from black to mid gray - or change the white offset, so it ranges from mid gray to white.

If you want to change both offsets, then you have to stretch the range. You do this by setting the white offset with the offset slider, then stretch the range towards black by using the black point control.

Use the Black Alert and White Alert indicators to see when your offset reaches -or crosses - zero. Areas darker than black or whiter than white will be shown as negative in the preview (when alerts are on).


Original photo


Offset 100

 

Black Point


More control than levels adjustment

This slider stretches the given range down towards black. It scales the entire range.

The Original dark photo shown just above was changed with offset 300 and then added black point compensated 67.

As a result the image encompasses the entire dynamic range from black to white, as a histogram would show. This is a nicer way to do levels adjustment because you have full control over the offset at either end of the scale and work on the luminance only with extra control over saturation since the plugin utilizes Power Retouches unique photographic saturation algorithm.


Offset 300


Black Point 67

Compared to adjusting levels in Photoshop, you preserve more color information in the highlights with our method.

 

Shadow Depth

Shadow Depth operates within the given dynamic range and, in contrast to Black Point, does not push the darkest pixels further towards black. It does an inverse compression within the range set by the darkest pixel and the value of the Shadow Threshold slider.

In the example to the right we fist compressed the shadows 100% at factor 90, then deepened the shadows 100% at Shadow Threshold 150. For the sake of illustration we have separated the two operations. In reality its better to do all operations in one go in order to preserve the most information. (Offset can be performed separately since it does not change image information beyond offsetting the histogram).


Sh 100% factor 90


Shadow Depth

 

Shadow Threshold

Shadow Threshold is a pair with Shadow Depth. It sets the brightness value above which no shadow deepening should occur.

 

 

Output Adjustments

 

Overall Effect

Compressed high dynamic range images are made by combining several exposures of the same image. This slider lets you control the combination algorithm. This control is particularly useful when compressing with factors above 95%. One of the advantages of this is that it can preserve more detail-contrast in the mid tone range.

Saturation

This slider lets you adjust the color saturation. It is an implementation of the power retouche photographic saturation

Web-design by Power Retouche photo-software plugins, tutorials and photoshop tips Web-design by Power Retouche photo-software plugins, tutorials and photoshop tips  
   
 

Photo credits

All photos by courtesy of Charlie Bustamente

 
Web-design by Power Retouche photo-software plugins, tutorials and photoshop tips
 

 

Graphic design by Power Retouche photoshop plug-ins for photo restoration and photo editing.
P A B B B C C D D D E E G G I L L N P P P S S S S S T T W W x A B B B C C D D D E E G I L N P S S S T T W
x P P F I P A P P P P P x x x -