High Dynamic Range (HDR) photography

2014.09.30 update: If you do not understand HDR photography, I suggest you read the post and then come back here for an update. In an email from HDRSoft , they pointed out something so obvious I cannot understand why I did not see it before. While you want a series of photographs that are several stops apart for HDR, the reason that cameras change the shutter speed rather than the actual f-stop to achieve this result, is that changing the f-stop (while keeping the shutter speed constant) will not just affect the amount of light getting into the camera, bit also alter the depth of field; on the other hand, changing the shutter speed (while keeping the f-stop constant) only alters the amount of light getting into the camera, and not the degree of focus anywhere in the photograph. As Homer Simpson says, “Du-u-h!!!” I also became aware of an excellent FAQ they have.

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I have had a few emails from people asking me to explain High Dynamic Range (HDR) photography a little more. Below is a photograph produced using HDR software that I recently took at Gilson Lake in New Hampshire. (More photos from that shoot to follow as soon as I can.) After that, the individual photographs used to create the final photograph are also shown.

The problem often facing photographers is how to manage scenes with both deep blacks and bright whites; or, in other words, scenes with a high dynamic range of light. If you open the aperture (also referred to as ‘f-stop’ or ‘stops’) enough to expose the parts of the scene that are dark, the bright sections will wash to pure white. If you close the aperture down to expose the bright areas properly so that you can see their details, the dark areas are just black.

HDR always uses an odd number of photos: a ‘normal’ baseline shot and then some number of photos with the aperture closed down and then the same number of photos with the aperture opened wider. Experience has shown that the best results are gained when each photo is two aperture settings away.

Thus the simplest HDR set of photos is one baseline photo exposed normally, one dark photo with the aperture closed down two f-stops and a third photo with the aperture opened up two f-stops above the baseline photo. Because of an article I recently read that experimented with the process and found no improvement over a five photo spread using 2 f-stops between each, that is what I use, and explains the count of photos I show below.

It is curious that while HDR talks about opening and closing the aperture, this is not what cameras actually do. In fact, modern cameras set up to take HDR photo sets simulate the effect of changing the f-stop by actually playing with the how long the shutter is left open: longer exposures are like stepping down the aperture up, shorter exposures are like stepping the aperture up.

Newer cameras come with the ability to do HDR photos in the camera. However, I have not seen any photograph produced this way that was nearly as good as one made using separate photographs combined afterwards using a good software product. For HDR shots, I use Photomatix by HDRSoft, which is generally agreed to be the best. Although at just under $100 it is not cheap, no one ever got into photography to save money, and the investment quickly pays for itself quickly with stunning photos. Even when taken by someone like me!)

Any camera set to take HDR photos must be in a manual mode, usually aperture priority mode. Most, if not all, Canon DLSRs can be set up to take HDR photos, by: 1) setting up Exposure Bracketing to two f-stops, and 2) setting the shooting trigger to high speed continuous. (I am sure manufacturers do the same thing. The HDRSoft website has both tutorials and a list of supported cameras.) That way the camera automatically takes the correct number of photographs with the aperture changes pre-selected automatically. While shooting from a tripod is preferred, steady, hand held shots also work well. (In fact, the sample below was hand held.)

And that is all there is to it. HDR photography is actually very easy and once you start you realize how many situations arise where it helps you create amazing photos.

Before viewing the photographs, I would also like to invite you to visit the poetry blog, the Book of Pain. As always, special thanks to my dearest Lyn, She Of Great Taste In All Things But Men, who does most of the photo selection. Thank you for dropping by the Book of Bokeh.

Produced via HDR:

IMG_2930_1_2_3_4

 

Normal, “baseline” shot:

IMG_2930

 

Four f-stops down:

IMG_2931

 

Two f-stops down:

IMG_2932

 

Two f-stops up:

IMG_2933

 

Four f-stops up:

IMG_2934

 

All photographs and comments ©2014 by John Etheridge with all rights reserved; not to be used without the expressed written permission of the copyright owner.

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31 thoughts on “High Dynamic Range (HDR) photography

    • Please, if you are interested, give it a try. My explanation takes about ten times longer to read than to actually do, because it is very, very simple. For me the hardest part, once I have set up HDR shooting, is to turn it off. A hundred times I’ve just turned the camera off and forgot about it and when I turned the camera back on for another shot, forgot that it was set up for HDR! In fact, honestly, I STILL do this! Plus, I should have mentioned in the tutorial that the software is free for the first 30 days, so there really is no down side. Plus the tutorials are excellent.

    • Thank you, and I wish I could take credit for the final shot. Alas, all I can take credit for was the purchase of the software! 🙂 To me, it is amazing to look at the individual shots and see that the final is so much more than their mere sum. Sometimes it is spooky, the effect!

      • Do you think that the HDR result brought the photograph closer to what your eye saw at the scene? I am having a friendly philosophical discussion about this with my son who thinks he wants to see everything as shot. I am always trying to get things up to my vision of what I saw, or thought I saw :-).

        • This is a very interesting question! The answer I think is both ‘yes’ and ‘no’. ‘Yes’ in the sense that our brain does do a lot of post image processing to enhance/straighten/color balance/fill in and detail any image we are looking at. That is why many photos we look at afterwards are so disappointing: what we ‘saw’ was better. ‘No’ in the sense that what HDR produces is probably more than the total amount of post processing our brain does. That is why when we look at such images they can really stand out in their uniqueness and detail. The line I personally do not want to cross is creating in a photo what is not there in the first place. (There are, for example, people who fill in pictures with dull skies, with partial images of turbulent clouds for the effect. That’s too far for me.) But if it’s there and the camera can capture it, even if my eye cannot, I am all for it. But I appreciate that this is my philosophy and I respect other people’s approaches on this point. Some go with ‘absolutely no editing’ and some feel there is no boundary that can be broken. My line is (I like to think) somewhere in the middle.

          Great discussion point, by the way! Thank you for raising it.

          • Thank you so much for your thoughtful response. After reading it, I thought a little more about boundaries and believe I am in the middle, with a few experiments onto the wilder side just for fun. I think your work with HDR is beautiful and quite subtle, a good example of post-processing.

            • Thank you very much! And like you (I don’t recall you saying that any of your photos are directly a result of HDR, but obviously you take a lot of care in balancing light and dark very, very well) it is important to me to balance beauty and reality. I have come to appreciate that some photos (and I am just as guilty as others on this) get to be too “overcooked” (as one of my correspondents called it) and just do not sit right on the eyes.

              Oh well, as everything else, live and learn!

              • I have done a little with HDR. If you would like to take a look in my archives section, one is Yellowstone Falls 12/8/13. I did this in Photoshop Merge to HDR. I thought it brought out the greens and that were too dark as shot. Another is Devils Tower 7/13/13 which was done with my Nikon in-camera HDR. There are a few more, but a small percentage overall. I’d like to try Photomatix, but haven’t bought it yet.

                • That Yellowstone Falls picture is fantastic, as is the elk photo. But that flowing water from the shoot photo is amazing! If you’d like to compare the Photomatix version to the Photoshop version of HDR, send me the originals and I’ll do one for you. If you don’t have the originals do another high range series of shots, send those, and we’ll compare the two. It would be interesting.

    • Thank you. I wish I could take the credit, but it really is the software. That’s the sort of thing it does perfectly. When I get around to posting all the pictures there is one where the green of the trees seems to shimmer vibrantly on the water. You almost feel like you can touch it!

  1. This is very cool! I didn’t know about this technique. I sometimes do similar by taking one shot ,putting it into photoshop, copying and reproducing as many as two or three copies as separate layers and then changing exposure values as well as color values on each of the separate layers and finally erasing off parts of the layers to expose the desired light or dark section.My results are probably not as effective as HDR but I like my results.Still, now I am curious about trying HDR.The images you have are so dynamic.

    • If you have gone to that much trouble in Photoshop then you will ADORE HDR. That software I talked about, and the free tutorials they offer. Check it all out. In fact, I think the software is free to try for 30 days. With your outdoor technique and expertise I am certain that you will find a great use for it!

    • photoshop does automated HDR merges:
      Choose File>Automate >Merge to HDR Pro. This works on Photoshop CS2 – CS6 (CS2 Doesn’t have auto align and it’s called “Merge to HDR on versions older than CS5. If your images were not taken on a stable tripod, this step may require checking “Attempt to Automatically Align Source Images” (which greatly increases processing time).You should be able to find plenty of tutorials online as well.

      • I’ve not used the Photoshop process, it would be neat to do a comparison of the two software’s approach on the same set of images. When I got into HDR the general consensus was that Photomatix was the best, but software mutates pretty quickly. Do you have any examples you really like?

        • I think here it is best to insert the old saying, “If it ain’t broke, don’t fix it.” The photos from your site prove that there is nothing broken about them, however you are doing it, so keep it up. The thing that amazes me about spelunking is the courage to squeeze through a tiny little channel and risk getting stuck. For me…not in a million years. I really admire your courage! 🙂

    • Well, thank you…although as is also clear from my shots, the perfection part is done by the software, not by any genius on my part! 🙂

        • Gosh no! Please forgive my bad writing if that was the impression I gave. In fact, it is very easy to do. The website I mentioned has several wonderful tutorials and their software is free to try for 30 days. My best piece of advice is for everyone to try it. IT’s just that if you get hooked on it, don’t blame me! 🙂

    • Priya, thank you! Yes, certainly, “overcooked” (an excellent word, by the way) is a good way to describe some of the things that you can do with HDR. I also find that if the original shots were hand held in low light and that each picture varies too much postionally from the other, the final tends to be a little over-cooked…like the software is doing too much compromising between scenes.

  2. Thank you for explaining this in terms I can understand. It seems better to let a camera do the ‘mixing’ for you but I can see where others may prefer to do it afterwards. Great looking final photo.

    • John, thank you! Encouraged by your site I experimented with the camera in my Motorola Razr. Oops, no go. Obviously the Galaxy has a much better camera and now I’m jealous…just one more thing I need to buy! 🙂 Although I am not convinced that a new phone/camera will give me shots as good as some of yours!

      • Thanks! The cam is nice but will not replace the traditional Canon or Nikon any time soon. But the manufacturers have come a very long way.

        Phone cameras in my view are fast replacing traditional cameras for the casual photographer.

        But say your taking a holiday in Bermuda, I wouldn’t trust the phone cam for those photos….

        A regular camera is less likely to have an OS meltdown and poof – all your photos are gone!

        • I have looked at ‘bridge’ cameras to carry when MY DSLR is too cumbersome, but at $400-$500 they are pretty expensive for the occasional use. Especially since their technology is improving steadily. On the other hand, the point and shoot Nikon I bought (see the Assault on Mt. Washington post) was a disaster. It’s partly Nikon (which I just do not like) and partly my expectations. I know Nokia sells a phone with a 40 megabyte (?!?!?) camera but that uses a Windows operating system and doesn’t have the 40+ hours of operation my Motorola has. Apple’s phones also have great cameras but I think they are otherwise poor bang for the buck. The Galaxy S5 is supposed to be a great camera but its battery life is poor. Aaaarrrgggghhhh!!!! What is the poor photographer got to do to get the absolutely perfect device?!?!? 🙂 Especially since I think of ‘patience’ as two four letter words smacked together!

          But I must say, I love many of the shots on your site. You have an eye and a sensibility that you use to make your camera work for you.

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