DRI stands as the title says for Dynamic Range Increase. Normally a digital camera can't capture the whole contrast spectrum of a scene like our eyes. Depending on how well it's sensor is made it can capture more or less contrast, but it's always less than our eyes can. Even my DSLR for 700€ can't capture the whole contrast like my eyes, but it can at least capture more contrast than my small compact camera.

Making a DRI Photo means to put multiple exposures of the same photo together and only use the well exposed part of each. On this way you can get beyond the contrast of every digital camera. Of course, the more contrast your camera can capture the less work you have.

Photos Suited for DRI

Photos for DRI should be taken with a tripod so they match 100% exactly onto each other. You can also use freehand photos, like I did in this guide because I didn't had no better ones, but then you should use a panorama align tool like Hugin to match them over each other. This is also the reason why my photos are looking a bit uncommon.

Other things you should be aware of is that your photos must not contain any movement because if you lay them over each other the movement doesn't match, except your camera can take all different exposures at once. Even the wind can mess a picture up if you have trees or grass or other wind sensitive objects in your photo. I had luck with my ones, it was a silent day. Moving clouds can also be trouble.

Needed Software

I would suggest you GIMP because I'm used to it but I think every image software that supports layers and partial transparency for these will do. Don't wonder why my GIMP looks a bit different than the normal version, I've used GIMP Photo based on GIMP 2.4.3 but don't worry, I'm not using any thing that isn't included in the normal GIMP 2+ versions.

If you want to use freehand photos I would suggest you also Hugin so you can align them to each other. Normally it's made for aligning panorama parts together but it does a good job for DRI aligning too.

Making the DRI

Now let's get started, for this DRI guide I will only use 2 different exposures. You can use more but I'm not done with learning how to do that the correct way, most of my DRI's with more than 2 parts are not really good and only most of my 2 part DRI's turn out well.

Loading the Photos

First load your photos into GIMP. The easiest way is to open the underexposure and load the other exposure(s) with "File > Open as layers (Ctrl + Alt + O)". Alternatively you can just drag them onto the opened darkest photo, they will get loaded as layers that way too.

Correct Order

The order is important for this guide, you need to order the exposures starting with the lightest on top going down to the darkest at the bottom. To do that you can Shift + Click the eye on the left of a layer to only show this layer. Then find out if its the darkest, the lightest or something between and drag it either on top of all other or below all others or where ever it should be. As you can see on this screen shot: I'm dragging with the left mouse button the layer that got the eye, which shows it's the only visible, below the other layer cause the one I'm dragging is the dark one. The other one is the lighter one. The black line shows where the layer will land when I release the left mouse button.

This screen shot shows the 2 layers,on the left the lower and darker one, on the right the upper lighter one. I cut the half away from the lighter one so I can show you that they match together. You don't need to cut your photos yet.

Getting it DRI

Now that you have correctly ordered your photos we can make the unneeded parts transparent. To do this, right click the lighter layer and click on "Add layer mask".

Then the "Add layer mask" window will appear where you select "Greyscale copy of layer" and check the "Invert mask" checkbox.

This is also the reason why the lightest photo needs to be on top, the inverted greyscale copy will make all parts of the picture transparent depending on their luminance. This means that the lighter parts will be full to nearly full transparent while the darker parts will be nearly to full non-transparent.

This is where the simple DRI guide ends. Of course you can get even more out by optimizing the layer mask and using more than only 2 exposures but these are things I have to learn my self first. But compared to the base photos the result isn't bad. It's a simple but still nice DRI photo.

I hope this guide will help you to make some nice DRI photos too.

The last page shows the final DRI and the split screen from before so you can compare them.

Thanks for reading.