Sunday, June 10, 2012

An introduction to HDR

High dynamic range images (HDRI) is used in many different places. Some of them may you be familiar with. Places like games and animated movies are some of them. This Word “HDRI” or “HDR” are a method to process images/videos. This allows a image/video to have a greater dynamic range between the lightest and the darkest areas.

HDR is also used in Photography. This is possible when taking multiple images of the same motive with different exposures and batch them together with a Photo editing software.

Not all Photo editing software can Batch images together. Some that can are for example Adobe Photoshop or a HDR software named Photomatix. Photomatix can be bought for about 40$ for the Photomatix Essential, and 100$ for Photomatix pro. I will recommend starting with Photomatix essential for those who are new to HDR.

A HDR image made of 3 exposures. (-2. 0. +2) 

How to take a HDR image

Like I said. An HDR images is a high dynamic range image aligned with multiple exposures edited in a HDR software.

What you have to do to make a HDR image is taking three images of the same motive with different exposures. Some cameras have a function called bracketing which is found somewhere in the menu.

When taking three pictures, a tripod is recommended to use. This will reduce the shaking that makes something called ghosting when we have putted three images together.

An image with “Ghosting”, after too much shaking when taking sources multiple images. 

Starting out

I will in this guide learn you step by step have to make HDR in Photoshop. I have basically described how, when using CS5. Earlier editions of Photoshop may have the same approach but, CS5 has the best HDR processor of them so far. So I recommend upgrading if you have any earlier edition.

When you have your multiple exposures photos ready, open up Photoshop and click file>Automate>Merge to HDR pro

Click on “Browse”, find your images and then “OK”

The Processing

A good rule to remember when I process images is, if it looks good, then then you have done something right. Anyway, with this rule in your mind, you have to follow a checklist to achieve a good HDR image.

Do not overdo images
Do not take the “HDR effect” to the top just because it is cool.
You have to remember what HDR are meant for.

HDR is as said, High Dynamic Range Images, which means that shadows and highlights do not loose details, and the images feels more “alive”. So use the different sliders carefully.

Halos
Halo is a glow that may appear around edges in different parts of the picture. This glow effect is not gooda good thing, and destroys the outcome of an image. The only way to avoid this problem is sacrifice some effects, and pull for example the “strength” slider downward.

Halos appear more often near bright backgrounds like oceans and skies. Try to avoid getting detail in front of these places. 

Skies are possible to not getting halos if there are white clouds in the sky.

And finally
Use HDR what it is meant be used as. Like I said make details in the shadows and in the highlights. This Will make Your Pictures outstanding.


Some personal tips

Experiment with different textures like rust, wood and stone. This will make interesting results.

Use light as an effect, but do not use Speedlight, no matter if the Speedlight is compatible with bracketing, this will destroy the natural effect of the image. Use tripod instead if there is a lack of light around you.

And the most important thing. Do not forget to look after possible motives around you. Be at Your guard. ALWAYS.

DOWNLOAD

This guide is also available on PDF for those of you that want to have it on the mobile,tablet etc.
You can Download it here.




No comments:

Post a Comment