How to create ‘High Dynamic Range’ images:
What is HDR ?
HDR means ‘High Dynamic Range’. Using these technique you can get excellent details in both highlights and shadows. You will be impressed by the artistic effect it creates.
You can get impressive results like this.

What do you need ?
1. Digital SLR camera, [or a camera which supports taking pictures in RAW format]
2. Tripod,
3. HDR software – photomatix.
You can also use Photoshop to create HDR. But photomatix is excellent software which gives you some more controls which is not there in photosohp.
You can also create HDR from jpeg image. But since jpeg is a compressed format, you will lose all details. The RAW file contains all details which we are looking for.
Taking Pictures for making a HDR
1. First set your camera in "Manual mode". Because the shutter speed or aperture should not change since we need the same depth of field in all photos.
2. Take a picture of your subject by setting aperture and shutter speed manually.
3. Then take more pictures with +2 EV and -2 EV. Now you have three pictures with +2,0,-2 EV. You can also take five pictures with +2,+1,0,-1,-2 EV. It is up to you. The time taken for combining 5 photos is larger than combining 3 photos.
4. Next we will see how to generate a HDR image.
Using a single RAW file to create HDR
Often we don’t get chance to take three or more pictures. You can use a single RAW file to 3 or 5 multiple exposure pictures. The main advantage to this is that you can produce a HDR shot with moving subjects such as people or cars. The disadvantage is that if you use an image with very dark shadows and you’re trying to boost the exposure, the result will be quite noisy.
Create 16-bit TIFF from RAW file
1. If you have 3 RAW files open in photoshop and save them as TIFF files.

2. If you have a single RAW file open in photoshop and adjust the Exposure values to +2,-2 etc., and save them separately.
Note: If you are using some other RAW editor, save the image as a 16bit TIFF without any metadata such as EXIF info. This is the important part. If you save it with EXIF info you will find that Photomatix relies on that info to produce the HDR shot. The problem with this is that the shutter speed and aperture values will be the same across the 3 images and Photomatix won’t know which image is -2, 0 and +2. Set the exposure level to 0, save that and then set it to +2 and save that image.
3. Now you will have 3 files. The size of each tiff file will be very large around 50 MB for a 10MP photo. Don’t worry.
Using a JPEG file to create HDR
All we need is 3 images with multiple EV values. Open photosohop, then load the jpeg image.
Add the exposure adjustment layer and set +2, 0 , -2 values. Save each file separately as 16 bit tiff.


Choose File –> Save AS –> and choose TIFF file type. [leave the default options as it is]
Generating a HDR image
Open the 3 images into Photomatix. From the menu select ‘Generate HDR’. Photomatix will ask you if you want to use the 3 opened images or load in some. Make sure it has “Use opened images” selected and click ok. Now Photomatix will confirm the exposures for each image. Many times it will get it right, but just in case make sure that each image has the correct exposure settings. Click ok, then check that “use standard response curve” is selected. If you are using 3 images taken at the scene tick the “Align LDR images before generating HDR image” option just so that Photomatix aligns the images for you. Click ok.



Be patient. Have a cup of coffee. It will take some time
Now you will be little disappointed with the outcome. Don’t worry because the magical thing is yet to happen.

Tone Mapping
This is the magic part. Using the Tone Mapping feature in Photomatix will convert your HDR image into something usable. Goto the HDR menu and select Tone Mapping.
You can see different options like this. Play with the sliders to get a sweet spot.
Luminosity
Strength
Color Saturation
White Clip – Black Clip
Micro-smoothing:
Light smoothing
Microcontrast
In my opinion, Luminosity and Light smoothing affects the photo more. So carefully adjust the sliders.
Increasing strength creates an artistic effect. Increasing colors saturation also increases noise.

Play with the settings. Don’t use the Default settings of Photomatix. I normally use the strength around 20 to get realistic kind of image. Be careful while increasing the color saturation. It adds more noise.
Break the Rules!!

After everything is over click PROCESS. Save the file as 16 bit tiff.
Post processing in photoshop
Next open the 16 bit tiff in photoshop. Adjust contrast, colors etc., using levels and curves adjustments.[In my case i added some yellow using curves adjustment]
One important thing you might have to do is reduce noise. you can use Filter –> Noise –> Reduce noise in photoshop.
There are lot of photoshop plugins available for this purpose. "Noiseware" , "picture code noise ninja" etc., use them.
Go to Image –> Mode and choose 8 bits / channel. Then save your image as JPEG.
DONE!!!!

comments and suggestions are welcome.