Ok, I think it’s about time I actually wrote something a little less self indulging- my first tutorial 
So this one is a ‘how to’, and the how to in this case is this;
Click the image for a big version. And in case you’re wondering, it’s Sheffield, UK.
This particular picture is made up of 25 exposures, blended into 5 HDR images, and then merged into one HDR panoramic. I’m using Photoshop CS4, but I know this is possible in CS2 because I did it
This tutorial assumes you have a knowledge of basic photo editing in Photoshop, and are comfortable using RAW to tweak images. This tutorial covers neither, only HDR and Panoramic photos.
So, I’m guessing if you are reading this you are probably interested in HDR and panoramic images. Unfortunately you have to know a little technical stuff about HDR at least before you can begin.
HDR simply means, ‘High Dynamic Range’. The dynamic range is the tonal range of the luminesce of an image. Simply put, it’s how much visual information that can be gathered from an exposure. A HDR image tries to replicate what the eye would see if looking at the scene you want to capture. Unfortunately, the dynamic range of even the top of the range cameras today, is no way near what is seen by the eye. If you expose for one area, there will always be other areas which are either under or over exposed. The HDRs role is to mimic light in the real world, by preserving detail in both highlights and shadows.
So what we do is take multiple exposures, and combine them into one HDR image. That is, we give our image a high dynamic range. To do this we have to take a few shots of the same subject, making sure we take each picture one stop apart. So for these I took five exposures, starting at -2, all the way up to +2. You’ll need a tripod for this, or the images won’t merge properly. You also need to shoot RAW.
Because I was aiming for a panoramic too, I simply rotated my camera around on the tripod, taking five bracketed exposures at each new location. You have to make sure the images over lap a little each time you shoot. This is because the way Photoshop merges the pictures later is by comparing pixels which are similar in multiple pictures, and then automatically using a blend mask to merge them.
Ok, so import your images, and have a gander. Not all that special at the moment are they? Should look something like this,
Not pretty huh? Notice the extreme over and under exposing I’ve got going on here.
Open them one at a time in RAW, you should be aiming to bring out the details of each shot, to maximise the tonal range of the area of the picture you exposed for. For example, in the -2 image, play around with the sky. In the +2 photos, you want to be evening out the tones in the darkest areas. Save your files. I’ll leave you to that. You could automate the process with a batch, but that’s cheating and it’ll effect the quality.
In Photoshop again, go to File>Automate>HDR. Select your five exposures you have for each picture. These are about to become a HDR. Click ok to begin. It’ll take a while, so leave it be. When it’s done, yo’ll get the option to play around with a setting I forgot the name of. Just move the slider around until you are happy with the exposure you are seeing. You want to make sure your sky isn’t blowing out in the highlights, although if you did a good job with your exposures, this won’t be a problem. Save it as an HDR.
Ok, now you just repeat that until you have all your HDRs.
Now comes the panoramic part. In Photoshop, go to File>Automate>Photomerge. An option box will appear asking how you want your image to be processed. This depends entirely on the type of shot you want to create, but for me I knew I wanted as much of the image to be shown as possible, and I didn’t mind the curved buildings and skies created by the wide angle lens. Auto works brilliant if you’re less ambitious.
Load your files and hit Ok. Then go and get a cup of tea, because this will take an hour or two. Maybe get a bath too, or watch a film or something.
So when it’s done you’ll have your HDR Panorama. Yay! You did it! Now you can tweak it to get the effect you want/desire. If like me you can’t resist editing without the rest of the adjustments under Image>Adjustments, then covert the image to a 16bit image via Image>Mode. You’ll now have access to the options you want. I duplicated the image, and separated the sky and buildings so I could work on each one separately.
