Ten Tips on How to Shoot HDR Photos without a Tripod

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1 Ten Tips on How to Shoot HDR Photos without a Tripod As a teacher of HDR (high dynamic range) photography, one of the suggestions I give my new students is that they need to have a tripod and use it to create the best, sharpest, HDR images. However, while that s the ideal situation, it s not always possible. This article is about how to best tackle shooting HDR hand held, without a tripod, the times when you have no other option. In May of 2011 I travelled to Turkey on a tour. I took a small tripod with me (called a Gorillapod - sometimes you can get away with this guy where a regular one isn t allowed, plus it s small to carry) and a backpack that with a clip to hold it on the outside. I was all set for some great HDR images in some historic places or so I thought! One of the first locations we visited was the Topkapi Palace in Instanbul. As I passed through the entry gate, security confiscated my tripod and told me I could retrieve it upon exiting the palace grounds. So, on to plan B shooting hand-held. I was a bit disappointed, it was also a major pain in the butt getting my tripod back and I almost lost my tour group as I had to go back around to the entry gate, while we were all meeting at the exit. Inside Topkapi Palace - Istanbul Fast forward to Hagia Sofia mosque, I thought I d try again to get the tripod inside. Ha! Sometimes I feel like somebody s got it out for us photographers, you know? Can you cut us a break please!? Needless to say, they took it again and I had a repeat performance of running out the exit, squishing out past everyone else running around back to the front, pushing my way through what seemed like a thousand people in line, to the entrance security booth only to discover that there, they move them to the exit for you. You ve got to be kidding me! Argh! By the time I convinced the security guy at the exit to let me back in that way, and got my tripod I really had to hoof it back to my group. Sweaty again. Time for a new plan.

2 What follows are some of the steps and settings I use to get the best results when I have to shoot without my tripod, which as you can see, happens quite often. Inside Hagia Sofia Mosque - Istanbul There are several reasons why you might have to use these tips, and shoot hand held. tripod use is often restricted or forbidden in some museums, churches and other venues you simply don t have one with you you re in a busy location and setting up a tripod in a crowded place isn t an option If any of the above are the case, follow the tips below and try shooting your HDR images hand held. I do it quite often, with a high level of success, because I follow these guidelines. 1. Set your camera on Auto Exposure Bracketing (AEB) to shoot variable exposures automatically. Different camera models have different settings for AEB. I use a Canon 5D Classic, and this and most other Canon models allow for a maximum of 3 bracketed shots. For most scenes that is sufficient IF you shoot those images at 2 stops apart. So you will end up shooting exposures at - 2, 0 and +2. If you can set what order the camera shoots them in, choose to shoot the +2 one first (you ll see why later).if you shoot Nikon you may find that you can only bracket in one stop increments, so if that is the case shoot 5 images: +2, +1, 0, -1, -2 and just delete the +1 and -1 images, you really don t need them. Some Nikons give you the option of shooting 7 or even 9 bracketed shots, but I d also shoot no more than a maximum of 5 images (that you will keep) total. So you could shoot, for example: +3, +2, +1, 0, -1, -2, -3 but dump the +2, 0 and -2 images and keep the other 5. Using more than 5 makes it tougher to get the images aligned in the processing stage because there s more chance of you moving between the exposures, and can result in a final image that s not very sharp or has edge alignment issues. So I recommend using 5 exposures maximum to create your HDR image.

3 3 shots using AEB - Shot at 32mm, f5.0, ISO 250, and shutter speeds of 1/4000, 1/1000 and 1/ Set your camera on Aperture priority mode. This will ensure that when it takes the bracketed exposures it will only change the shutter speed, not the aperture. Changing the aperture from one shot to the next will cause changes in focus in the images from one to the next and will create major alignment problems, sharpness issues and could cause really odd halos around things. For that reason, you always want to change the shutter speed only when doing HDR, this is no different. So setting to Aperture priority mode you will make sure the aperture doesn t change from one shot to the next. Now, having said that you also need to keep an eye on your shutter speed and see what the camera ends up shooting at, especially for the +2 or +3 shots. That s why I mentioned setting the camera to take the most over exposed shot first, so that you can see what shutter speed it will use to take the longest exposure and if you will end up with a shutter speed that s too slow to keep the image sharp. 39mm focal length, f5.6, ISO 200, shutter speeds 1/2000, 1/500, 1/125th

4 What shutter speed is too slow? How do you know when you ve gone too far with your shutter speed? What we want to avoid is what s commonly called camera shake. This is literally the camera movement caused by your hands holding it. You can t hold the camera steady for long exposures, even if you stand really still. We have a limit, that s why tripods were invented. But if you follow this rule of thumb it will give you an idea of how slow is too slow (as a starting point, you may be super steady or super shaky, to try with your own equipment to find your limits with your camera and lens combination) and make sure your shutter speed stays above that setting to avoid camera shake. Ready for it? - Keep your shutter speed faster than 1 over the focal length of your lens! Huh?! Okay, what that means is if you are using a zoom lens at the 200mm setting, you need to shoot at 1/200th of a second or faster to keep things sharp at that focal length (200mm). If you re at 50mm than 1/50th will do it. The longer the lens the more amplified camera shake is, so you need a faster shutter speed to keep it sharp. So what happens then if you set up your bracketed shots and your longest one is too long? Keep reading, we ll put it all together shortly! 3. Keep your ISO set as low as possible. The HDR process of tone mapping and combining exposures tends to add noise into images, especially in the dark or shadow areas. So to minimize that, you want to keep your ISO as low as possible ideally 100 or 200. However, in some situations you may not have an option but to bump it up a bit. Using the tip above, if your shutter speed on the longest exposure is falling in the 1/15th range and you simply need to get more to avoid camera shake, you have two options. Option #1 open the aperture on your lens to the widest or wider one (f/2.8 for example). But you may not want to do that because that will sacrifice depth of field, OR you simply may not have that option with the lens you have if its

5 maximum aperture is say f/5.6 and you re already there. So then there s option #2 increase the ISO just enough to get the desired shutter speed. Keep in mind that if you do this your final image may require some noise reduction prior to the tone mapping process, and some more noise reduction afterwards. If it s a case of getting the image or getting nothing though I d probably bump my ISO and get a noisy image as my preference over none at all. I had to bump the ISO to 800 to get this shot and keep my shutter speed to 1/20th for the longest exposure. I shot with a 17mm lens at f/3.2 (its max) so my only choice was to use a higher ISO. The final tone mapped HDR image had odd color shifts I couldn't remove (possibly from the noise and high ISO setting used) so this ended up b/w but I think it's still successful. 4. Set up focusing. The issue with focus is that as you fire off your 3-5 bracketed exposures, you do not want your camera trying to refocus between each shot. It may miss or change slightly and you ll end up with big problems. If your camera has an AF/AE-Lock button (most Nikons have one to the right of the viewfinder or eye piece), set it up to lock both the focus AND the exposure. Then press it down to lock both, hold it in and then press the shutter button to take your bracketed shots. For most Canons, they have some version of this option in custom settings (check your manual), where you can set it up to use the * button on the back of the camera, to lock the focus independent of the shutter release button. So you focus using your thumb on the * (you don t have to hold it once it locks) and take the exposures with our index finger. If your camera doesn t have such a thing, you can also focus using your lens autofocus, then turn it off to manual. This is a bit clunkier though and you can end up moving while you re doing that. Another thing you want to make sure of is that your camera s focus (AF) setting is on single for Nikon, and one shot for Canon, that ensures that camera isn t trying to continually focus. Lastly make sure your camera is set to single point focusing, meaning you choose which point the camera focuses on. You do NOT want it choosing where to focus!

6 28mm lens, f/5.6, ISO 250, shutter speeds of: 1/640-1/160-1/40 - I could get away with 1/40th only because I used a 28mm lens. Had I been using a 200mm lens I'd likely have gotten a blurry image due to camera shake. I wanted to use f/5.6 to get a bit of depth to my focus and get the rock walls sharp all over. 5. Next, brace yourself and get a reference for your image framing. What I mean by that is, as you look through the viewfinder (if you shoot using the Live View mode and look at the screen instead of through the eyepiece get used to shooting the other way and turn off live view unless you re doing video, it s MUCH harder to hold the camera steady shooting in Live View mode) make a mental note of how the image is framed. What s in each corner, is there something dead smack in the center you can concentrate on keeping in the center? Basically you want to make sure you move as little as possible from one frame to the next to make for better, more accurate alignment later. If your camera has an option for touring on a grid inside the view finder, use it to keep the image aligned. Brace yourself the best you can, keeping your elbows in tight to your body, and your left hand under the lens, not on top of it. Breathe out and hold it, or just hold your breath. Lean on something solid like a table or wall if you have the option. Just get as solid as possible and don t move!

7 If you take a real close look at this image, especially around the window and the pillow in the lower right corner of the frame, you can see that it's not perfectly aligned and there's a greenish color fringe on the edge of the pillow. This is likely caused from my longest exposure not being 100% sharp (at 1/15th) or perhaps I swayed or twisted the camera angle slightly between shots enough to make it an issue. I still think it's a good shot, but I may reprocess it and see if I can get it aligned better. This is why you want to be still!

8 6. Set your camera on high speed shooting mode, or motor drive, to shoot the frames as fast as possible one after the other. If your camera shoots 3 frames per second that s good, if it shoots 10/second that s even better. The idea is you just want to press the shutter once, let the camera rapidly fire off all 3 or 5 you re bracketing, then release your finger. This will help minimize camera movement between frames as well. 7. Use your exposure compensation to adjust all the exposures if you need them a bit brighter or darker. Your histogram will tell you if you have enough information in the shadow areas of the darkest image ideally you want a gap in the histogram on the left hand side. Likewise on the highlight side (bright areas) you want a gap there on your darkest exposure and no flashing highlights that are blown out. If you shoot your 3 bracketed exposures and take a look at the graphs but that s not happening, let s say your darkest one is still too bright. You can shift all 3 of the bracketed exposures down by using the Exposure Compensation setting. Dial in -1 or -2 and the whole set will move down the scale accordingly. Shoot again and see if that set is any better. If in doubt, do a couple options and see which process better later in computer.

9 8. Shoot it, then shoot it again! Because what we re trying to do here is quite challenging the results can sometimes be disappointing later when you try and process the images, shoot a backup. So, just like you are bracketing the exposures, bracket the whole set by doing it twice. Usually one of them will come out better, sharper, easier to align often the second set. 9. Review your set or sets of images and flipping through them see how well you did holding still. If you scroll through them and you see drastic jumps from one image to the next in the series, you may want to shoot it again before moving one. Then zoom in on your camera to see them closer up. Check for focus and sharpness and if there isn t any you may need to shoot again and review your settings, particularly shutter speed. Once you leave the location you can t fix it later, so make sure you ve got what you want and it s sharp before you move on. 10. Lastly, a computer step, as I mentioned earlier you may need to do some noise reduction on your set of images prior to using Photoshop or Photomatix to do the HDR tone mapping process. This will reduce the amount of noise going in, if you ve used a higher ISO. My HDR software of choice is Photomatix but sometimes for hand held images that are tougher to align, I will use Photoshop CS5 instead which does a better job on challenging situations. Try both and if you re not getting a good result on one, try the other. Sometimes I ll even do the alignment process in PS CS5, save the HDR image, then open it and tone map it in Photomatix, which I find does a better job of that part. It s all about the workflow you develop and what works for you, this seems to work for me. Here s a couple more HDR s done hand held.

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