The most important part to digital exposure blending is to autobracket the correct way, giving you a solid base to edit your image in Photoshop. You can’t create a stunning photo in post process – you can only improve upon a great image.
With that in mind, I’m going to show you how to execute an autobracket the correct way so that you can capture images with an outstanding tonal range, like this one:
I’ll also explain how to bracket your images manually for those instances where autobracketing is too limiting for your environment.
It’s very important that you have a sturdy tripod – one that’s capable of withstanding the weight of your camera, lens, and your tripod head. Solid legs with a good grip are imperative to not only hold your camera in place, but to make sure it stays there when you change your settings, adjust your focus, or if a strong wind comes along. Even the slightest movement can alter your alignment, making it more difficult to exposure blend in Photoshop.
Place your camera on your tripod and adjust your focus properly. Please read my focusing tutorial here as this is a very important step to ensure that you have consistent images.
Switch into aperture priority mode so that your camera will only change your shutter speed to alter the exposure and NOT your aperture – otherwise you’ll have an inconsistent depth of field, making it near-impossible to exposure blend accurately.
Follow the instructions in your camera manual to turn on your auto-bracketing. This is usually a simple process with a few clicks and adjustments.
Hold down the shutter button while your camera takes three consecutive images. When finished, review the histogram to make sure that you’ve have the proper tonal range to work with – meaning that it indicates you captured one image with no blown highlights and another with no blocked shadows.
When finished, you should see something similar to the images below:
Your base image – one that has been metered on average (evaluative).
Your longest exposure – horrible for the sky but it eliminated the blocked shadows from your foreground rocks nicely.
Finally, your least exposed image – the blown highlights in the first two photos have been eliminated (except, of course, for the center of the sun) and has given some nice shape to the sun as well.
At times, you may find that your camera’s autobracketing system is too limiting for the tonal range you’re working with – usually only +/- two full stops. If you’re shooting a high-contrast scene with many highlights and dark shadows (such as the sunset above), two stops will certainly not give you the full tonal range where all your shadows and highlights are recovered.
When this happens, you’ll have to abandon the autobracketing and do it manually, which is also quite simple to do.
Autobracketing is great because you can press some buttons and capture three exposures without having to adjust your settings. In reality, it’s only a time saver – autobracketing does nothing more than what you can do manually.
Repeat step 1 above and set up your tripod, but instead of turning on your autobracketing, just meter your image (in aperture priority mode) and make a note of your settings. The aperture you choose to use should always remain the same throughout your images – instead, you’ll be adjusting your shutter speed.
Switch into full manual mode (your instructions will tell you how to do this) and set your aperture and shutter speed to what it was when you metered. Take one image, then adjust your shutter speed two stops faster (underexposed) to capture another image. Check your histogram for any blown highlights – if you still see some overexposed areas, keep increasing your shutter speed until they disappear. Repeat this step for your shadows as well – continue to decrease your shutter speed (overexpose) and check your histogram until you see that your unrecoverable shadows are fully exposed. During this process, never change your aperture or ISO to ensure that you have smooth exposure blending.
Hi Chris, great ebook I’m learning a lot! I have a Nikon D90 and when I’m selecting options for raw files it has raw+fine, normal or basic. I am thinking in your reference to low res you mean basic? The raw file part is new to me so I’m really a beginner.
Thanks Lainy
Hi Lainy – you are correct
All this will do is save on memory space, so don’t worry too much if you choose a high-quality jpg preview. In fact, if you know you might want to work in JPG and bypass RAW editing all together (such as a sports event where you’d be taking hundreds of images), then it would be best to just shoot in fine-quality JPG. But for landscapes and other situations where you know you want to do a lot of editing, and want the best possible image, you’ll find that RAW format plus a low-quality JPG (for preview purposes only) is your best option, and is how I normally shoot.
Hello Chris,
Sure appreciate your time and advice so succinctly given. My question is, when manually stepping down or up the exposure can I just leave my camera (canon 5d II ) in aperture mode and just apply the quick stop settings on the scale bar without having to switch to Manual
Hi Denise –
I’m happy you found this helpful
You can certainly leave your camera in aperture priority mode and let your camera’s autobracketing feature do the work – that is what I usually do (unless I am shooting panoramic). The only issue with that is sometimes, you need to step outside of your autobracketing limitations (usually +/- two full stops) in order to capture the full tonal range of your image. So if you autobracket your image, and find that the underexposed bracket still has blown highlights, or the overexposed one has blocked shadows, you will need to go into full manual mode and adjust your shutter speed manually until you’ve recovered all the detail.
Thank you Chris, There is an Exposure Compensation quick selection on my camera that goes from -2 to 0 to +2, I guess my remedial math question is… Do you consider that a four stop or two stop range? Also was wondering, what would be the widest Exposure extreme you would use to keep it natural looking?
Hi Denise –
Theoretically, -2/+2 would give you a four stop total range from the fastest to slowest exposure. However, if you’re shooting in RAW format, you have a “safety net” of two exposures in either direction. Ideally you should obtain the correct exposure in camera for the highest quality, but if you factor in the ability to adjust your exposure in RAW (which allows you to + or – your exposure up to two full stops)….you would have an eight stop total range with autobracketing.
Your exposure range is entirely dependent on your scene…and could be many stops depending on your intent. I’ve had images where the shadows were so deep I had to go 8 full stops over my base exposure to eliminate them. Although it did not look natural to completely eliminate those shadows, I wanted to have that data to work with for post processing and in the end, I burned those areas to at least appear as though the shadow remained – in reality, all the data was there, just near-black.
You’ll find that there’s a delicate balance to all of this, but ideally you want to capture as much data with your camera as possible, and then you can always remove it later in post process if it does not have a natural appearance – it’s much better to have the data and not need it than vice versa