Single image hdr

before

after

I know that you can process a single raw image in photomatix as well as in CS5 with some good success. I've been trying a new technique and getting, what I think, is much better results. It's simple but requires a few more steps in the beginning.

Shoot raw

Open the Raw image in photoshop. I don't think the version matters.

Save this first image as a tiff. That's your mid-range exposed image

Open an Exposure layer in the layers pallet

Change the Exposure to +2 and save this as a TIFF. Make sure that you give it a meaningful name. "+2" will work

Now change the Exposure to -2 and save as a TIFF. Give this image a meaningful name also.

Do the same thing with -1 and +1.

You now have a single image with 5 different exposures all saved as TIFF files.

Open photomatix and process as you normally would.

Let me know how this works for you.

Color correction - a tutorial

I realize there are many ways to color correct your pictures. Here's the way I do it.

Before we start there are a few "one time" steps that should be done.

From the Tool Pallet, open the "color sampler" tool. At the top you'll see "Sample size". For high res images, set it to 5x5. For low res, 3x3.

1. Open a "curves adjustment" layer. There are 3 eye droppers on the left hand side. Double click on the top eye dropper. Set the RGB numbers to 7,7,7 and click OK. Next click on the middle eye dropper and set the RGB numbers to 128, 128, 128 and click OK. Last, click on the bottom eye dropper and set the RGB numbers to 247, 247, 247 and click OK.
   
   This is the only time you will will have to set these numbers.

In the Layers Pallet, open a "Threshold" adjustment layer

Move the little white triangle all the way to the left, the "Threshold level" is 1. Slowly move it back to the right until a meaningful shape appears

In the tool bar, I choose the "color sampler" tool. Hold down the shift key and click inside the meaningful black area. This places a circle with the number 1 at that spot. This is my Black point

Now I move the same white triangle all the way to the right. The "Threshold level" is 255. Change the "Threshold level" to 254 and look to see if any new white pixels appear. If yes, I hold down the shift key and click on that pixel. A number 2 appears. This is my White point. If no pixels appear at 254, I move to a lower number until one does appear. (Note: There are times that I have to zoom in on the picture to see the areas while looking for this white pixel) I'm looking for the first white pixel below 255. If I use the white pixels showing when the "Threshold level" is 255, no correction will occur in the next step.

In Versace's new book, "Welcome to Oz 2.0", he adds the following step to find the mid-point. Actually, he learned this from Dave Cross, one of the Photoshop Guys. It works great.

Creat a new Layer > Edit Fill, select 50% Gray from the Contents dropdown menu > click OK.

Change the blend mode to Difference

Select the Threshold adjustment layer and move the slider all the way to the left

Move the slider to the left until you see the first or second black pixel

Zoom in and place a sample point on the pixel

Discard the Threshold and 50% gray layers

Your image should now have 3 sample points

I have located my Black point (1) and my white point (2) and mid-point (3)

Next, I open a Curves adjustment layer again

On the left hand side I again locate the 3 eye droppers. Click on the top eye dropper. This will set my black point. I move the cursor over the point #1 and click. I see a change on the graph in the Curves dialogue box.

Click on the bottom eyedropper back in the Curves dialog box. Move the cursor over the second point I set (2) and click. This will set our white point.

Do the same with the middle eyedropper to set your mid-point

Vincent even goes so far as to use 3 individual Curve layers so he can go back in and make some additional correction if needed. I understand that for the type of work he does, but for my work I don't find that necessary.

The image is now color corrected.

This process takes a few more steps, however I find it to be very accurate.

A Basic HDR Tutorial - Part 3

In this part of my tutorial series I'm going to tell you some things I've learned through trial and error.

Here are a few keyboard shortcuts that will help speed up the experimental process.

Windows:

• Ctrl + Z (undo/redo)
• Ctrl + Alt + Z (step back)
• Shift + Ctrl + Alt + E (stamp visible)

Apple:

• Cmd + Z (undo/redo)
• Cmd + Alt (step back)
• Cmd + Opt + Shift + E (stamp visible)

Remember that there are no rules when it come to processing HDR pictures. After the image comes out of Photomatix I strongly suggest that you take the time to analyze it. I can't stress this enough. Use the "image mapping" process I described in Part 2 if necessary. It will slow you down and give you time to develop a Processing Strategy. The picture may be dull and lack contrast. The colors may be muted. There may be areas that are blurred, etc.

This is what I do after Photomatix:

• Develop a strategy
• Work from Global Corrections to Local Corrections
• I follow my normal work flow but I remain flexible. Every picture is different
• Color correct. There are many ways to do this. Pick you favorite
• Proceed to the process explained in Part 2 of this tutorial series if I need to combine areas from different images, i.e. replace or repair the sky with the original, fix moving objects

At this point I stop and again analyze the image. Now I start looking for the areas that need Local Corrections, i.e. contrast, sharpening, saturation, special lighting, etc. There are many tools in Photoshop to do these adjustments. All of these I do on separate layers utilizing a black layer mask. Then I use a soft white brush set to about 20% and paint in the look I'm after. By using a 20% brush I can slowly bring out the effect. (Think of yourself as an artist painting on a canvas).I can always back up if I've gone too far, (Ctrl or Cmd + Z).

I then try my favorite plug-ins. This is pure experimentation. I keep my eyes focused on just the area(s) I want to enhance. Remember, the Black mask I'll add will hide the entire effect. I'll just paint in what I want with a soft white brush. Am I repeating myself? That's how important the mask is. The plug-ins I use make adjustments faster and easier.

• Topaz Adjust - I try different filters
• Color Efex Pro 3 - There are great filters in this package. The magic grail is Tonal Contrast. Used locally it's wonderful
• Viveza2 - The "U" point technology saves time
• Imagenomic - Great noise reducing software

(Here's a hint. If you have a child or know a child in school, grammar school, high school or collage, check out Academic Super Store for these and other programs. You'll be shocked at the savings.)

One of my all time favorite filters in Photoshop is "Lighting Effects", (filter > render > lighting effects). This is how I do it.

• I duplicate the layer or use the "stamp visual" keyboard short cut
• I change this layer into a smart object (Layer > Smart Object > Covert to Smart Object) This will allow me to go back into the filter dialog box and make changes
• I set the style to "Soft Omni" and play with the other sliders. You'll thank me for this one

• Noise reduction. I like to do this near the end of my processing

Work the image. Look for little details. The process is the same. The more times you do it the easier and faster it becomes. Experiment and practice.

I invite you to visit the following sites. Not to copy what you see, but to see what can be accomplished.

1. Stuck-In-Customs - Trey is the "Jedi Master" of HDR
   
2. HDR Spotting

Suggested reading:

1. A world in HDR - Trey Ratcliff
   
2. Complete Guide to High Dynamic Range Digital Photography - Ferrell McCollough

I leave you with some final thoughts.

• Good HDR pictures start with a good image at the point of capture. There is no substitute for this.
  
• Take time to analyze the image that comes out of Photomatix and develop a strategy
  
• There is no right or wrong. Experiment and develop your own style.
  
• Above all else "HAVE FUN".
  

I'm available to answer questions at akesselhaut@hotmail.com.

(from time to time I'll update this HDR tutorial. I'll post the update on this blog)

A Basic HDR Tutorial - Part 2

Now that you have your 3 images at +2 / 0 / -2 on the computer, you're ready to bring them into Photomatix for processing. I hope that you took the time to look at the Photomatix website for their tutorials. If not, click here and take a quick tour. They explain their product in great detail with some very fine illustrations. If you care to go further, they also have some good videos.

Photomatix shows how to load the images to be processed in step 2 of their tutorial. In the next step there are some choices.

With the "Generate HDR - Options" dialog box open, this is what I recommend.

Align source images - I have that box checked. It doesn't hurt to do that, even if you used a tripod.

I do not check "Reduce chromatic aberration, Reduce noise and Attempt to reduce ghosting artifacts." These corrections can be made in Photoshop later if there's a problem.

I click "Generate HDR" and Photomatix will merge the 3 pictures into a single HDR image.

Don't get scared when you look at the screen when Photomatix is finished. What you are seeing is a 32bit/channel image that your screen can't handle. The next step is where the fun starts.

Tone Mapping converts the 32bit/channel into a 16bit/channel TIFF or JPEG image that the screen can handle. At the bottom of the dialog box, I click "Tone Mapping". That brings up a dialog box with a lot of sliders. I'm only going to use a few of these to start. Once you get the hang of all the previous steps and process multiple images, you may want to experiment with the others. I don't bother with them at all. I'll show you my settings below, but first, a major point. Every image will be different. These setting will work fine as a starting point, but over time you will find the ones you like. Personally, I don't like the over-the-top HDR images. My settings will reflect that bias, however I invite you to experiment and find what works best for you.
This is the dialog box you will see. Start at the top and work your way down. We'll be using the "Details Enhancer" process, so make sure that's on. Please pay attention to the histogram and the preview image. The preview image will give a general idea of what the final processed picture will look like, but remember this is only an approximation. The histogram is important. Try to get as much information as possible centered in the box, with little or no highlight or shadow clipping.

Strength: I leave this at 100.

Color Saturation: I like to do my color enhancing in Photoshop where there is more control, so I stay in the 50%-60% range. Move the slider back and forth to see what looks best.

Luminosity: This controls the brightness of the image. Moving the slider to the left makes it darker and to the right to makes it lighter. This can be modified in Photoshop later, so don't worry about it at this point and experiment to find the settings that suit you.

Microcontrast: This slider increases or decreases detail. I keep my slider between 1 and 2. Move the slider back and forth until it looks good to you.

Smoothing: This determines the overall look of the image. The higher the setting the more natural the look. The lower the setting the more unnatural. I keep mine set to High.

White Point and Black Point: I move the sliders back and forth until most of the histogram information is centered.

Gamma: I leave at 1.00.

I don't do anything with the other sliders.

Click Process

Here's an important trick. If you don't like the way the processed image looks and you want to start over and change your settings, just press and hold Control+Z to step back to an earlier screen in Photomatix.

I have talked to other photographers who have tried Photomatix HDR processing and didn't like the results for one reason or another.

THIS IS THE KEY CONCEPT FOR HDR: Processing with Photomatix is only the beginning of the HDR process. The image that comes out of Photomatix usually looks flat and may have other issues. It must be brought into Photoshop for further processing. You can use your normal work flow and/or introduce corrections from plug-ins. You can process it again in Photomatix. There are no hard and fast rules for HDR Processing. Experiment, experiment, experiment. You can always use the "Control + Z" keyboard shortcut to move back one step or the "Control + ALT + Z to move back multiple steps, or just start over.

The first thing I do is take a few minutes to study the image. I learned this trick from Vincent Versace. Maybe it's not a trick but it certainly helps in my work flow. He calls it "Image Mapping". Image Mapping is a process by which he creates a new layer, clicks on the pencil tool, increase the Master Diameter to a good working size and draws out his strategy by making notes on the image. In the beginning it helped me to analyze my images and plan my correction strategy. (See the image below.) Give it a try.

Now that I'm in Photoshop with my 3 original pictures and my Photomatix processed image, I want to combine them and use the best parts of each. I may need all three of the originals or just one. Most of the time, I use the darkest and the middle exposed pictures. In the following example, I'm only going to use the image where the people are not blurred but the same steps will hold true if you use 2 or 3 images. I always make the big corrections (global corrections) first and then work towards the details, (local corrections). In the example above, I have indicated that I want to replace the blurred figures with those that are in not blurred. Here's how it's done:

I open the Photomatix processed image

Next, I open the original pictures where the people are not blurred and process it in Photoshop to have the same visual qualities as the Photomatix image. It won't be exact but it should be close. I click on the "Move Tool" ("V"), hold down the "shift key", click, drag and drop it over to the Photomatix image. I will now have the 2 images in perfect registration and both layers will be shown in you Layers Palette. I like to name my layers so I'm not confused later. To do this, I put the cursor on the layer name and double click. Type in something like "reduce ghosting".

At this point, we should discuss "Layers" and "Layer Masks". Layers and Layer Masks are the backbone of the final processing of our images. Here and here are additional tutorials for you to see. I strongly suggest you take the time to learn and understand them both.Next I add a "Layer Mask" to the top layer. (click the "add layer mask" icon at the bottom of the layers pallet [the gray square with the white circle]).

Here's another tip from Vincent Versace. He calls it the 80/20 Rule. If you're going to use 80% (+/- ) of the top picture, you'll use a White Mask, revealing the entire top image or, if you're going to use 80% of the bottom picture, you'll use a Black Mask which will hide the top layer completely and reveal the bottom layer. I hope that makes sense but once you try it you will find it easier to understand.

Here's the 20% (+/-) part. If I have applied a white mask I do the following:

I make sure that the Foreground and Background colors are at their default setting by pressing the "D" key. I have the Foreground color set to Black. I can switch the Foreground and Background colors by pressing the "X" key.

I click on the Brush Tool ("B") and check to see that the Opacity is set to 100%. I use a soft brush in a size required to accomplish the task at hand and change the size by using the right and left bracket keys as needed.

I make sure that the Layer Mask is active in the Layer Panel by clicking on it. I paint over the areas of the Lower Layer that I want to reveal. I don't worry if I make a mistake. If I do, I can switch the foreground color to White by pressing the "X" key again and paint over the area I want to fix with a White brush.

If I applied a Black Mask revealing the entire bottom layer, I would set my Foreground color to White and paint with a White brush and make corrections with a black brush.

When I have completed the work with these layers, I "Merge Down" by pressing and holding the Control Key + E. If I then want to introduce parts of another Original Picture, I do the same steps over again, using another image.

At this point I use my noiseware filter. I have found that Imaginomics Noiseware Pro works great using just the default settings. If I want to introduce some noise, I use the Opacity slider.

I given you a lot of information. Practice the above steps. Don't be afraid to experiment and make mistakes. In Part 3, I'll discuss some addition tricks and suggestions to help complete the process.If you have any questions, please email me at akesselhaut@hotmail.com