Thursday 26 June 2014

7 tips for low-light landscapes


The vast majority of landscape images are taken during the hours of daylight, with the ‘golden hour’ around dawn and sunset finding particularly favour amongst enthusiast and professional photographers.
However, the hours before dawn and after sunset can also be very productive with long exposures creating images that transform night into day.
We’ve put together a few tips that should set you on the right track if you fancy giving low-light or nighttime landscape a try.

7 tips for low-light landscapes the pros all swear by: 01. Check the moon

1. Check the moon

You need some light for nighttime photography and this can be provided by the moon, or more correctly the light from the sun reflected by the moon.
It’s not essential that the moon is full, but it’s helpful if it’s fairly large in the sky, so check the phase of the moon and weather to decide the best dates for your shoot.
You can find information about the phase of the moon on the internet or, if you have an iPhone or Android phone, you might like to install MoonPhase (iOS) or the MoonPhase Widget (Android).
When you’re composing a long exposure image at night avoid including the moon in the frame as it will move while the shutter is open and be recorded as an oval.
Alternatively, you could shoot a couple of images, one long and one short and perform a little cloning to make a composite.

2. Set a low sensitivity value

In very low light it doesn’t matter how high you push the sensitivity value you still won’t be able to use a safe hand-holdable shutter speed.
In any case, you don’t want to introduce lots of noise by using a high setting, so it’s better to use a low value and put the camera on a good, solid tripod to keep it still.
Ideally keep the sensitivity to ISO 400 or lower.

7 tips for low-light landscapes the pros all swear by: 02. Select a low sensitivity value


3. Focus manually using live view

7 tips for low-light landscapes the pros all swear by: 03. Focus manually using live view

Ideally when shooting a low-light or night-time landscape, you should arrive early so that you can compose the image and focus the lens in decent light.
Once the scene is in focus, set the camera to manual focus so that it won’t adjust or hunt when you press the shutter release.
In the real world, you may not be able to arrive early, or you may want to photograph more than one composition during the same evening, in which case you will have to focus and compose in less than ideal conditions.
Unless the moon is very bright most AF systems will struggle to focus in very low light and it’s a good idea to focus manually.
This is tricky with an optical viewfinder, but if your camera has an electronic viewfinder the gain applied to the image should make the scene easier to see so that you can focus.
Alternatively, use Live View (which also applies gain) and compose the image on the main screen with a magnified view of the target area (ideally at the hyperfocal distance).
You may find it helps to shine a torch on the subject when focusing. If this fails, use the distance scale on your lens to focus.

4. Use a remote release


7 tips for low-light landscapes the pros all swear by: 04. Use a remote release

A remote release, either cable or wireless enables you to trip the shutter without actually touching the camera and setting it and/or the tripod wobbling.
Although it’s good practice to use mirror lock-up or exposure delay mode with a DSLR to give the vibrations set off by the mirror movement time to die down before the shutter opens, it’s not strictly necessary with exposures that are several seconds or more long.
It’s also not an issue with compact system cameras as they don’t have a mirror.

5. Use long exposure noise reduction


7 tips for low-light landscapes the pros all swear by: 05. Use long exposure noise reduction

Most cameras have two types of exposure reduction, high sensitivity and long exposure.
This is because the noise that appears as a result of a long exposure tends not be random like high sensitivity noise, but occurs as a result of variations in the sensor and ‘hot pixels’.
In long exposure noise reduction mode the camera records two images in succession, the first is the actual image while the second is a ‘dark frame’.
This is taken with the same duration as the original image exposure, but with the shutter closed.
The camera then analyses the dark frame and extracts the noise that it finds from the normal image automatically.
This system usually works very well, but it can be frustrating having to wait for exposures that are effectively twice the length they would normally be.
If you prefer you can perform dark frame subtraction manually using specialist software or Adobe Photoshop to reduce the length of time each exposure takes.
However, the dark frames should be created periodically throughout the shoot as the sensor heats up during long exposures and this creates more noise.
Each dark frame should be the same length as the image exposures and are recorded with the lens cap on and the viewfinder covered.

6. Use graduated ND filters


7 tips for low-light landscapes the pros all swear by: 06. Use graduated ND filters

Graduated filters can be just as useful for low-light landscape photography as they are in normal daylight as the sky.
They’re especially useful around sunrise or sunset when the sky can be significantly brighter than the ground beneath it.
It’s often tricky to position the graduation correctly in low light, so it may help to take an image or two at a high sensitivity setting (to allow a relatively short exposure) purely to check the position of the graduation on the back of the camera.

7. Don’t forget


7 tips for low-light landscapes the pros all swear by: 07. Don't forget

Naturally it’s harder to find your kit in the dark, so don’t take anything that you don’t need to avoid expensive losses.
A torch is essential in most cases for helping you find stuff in your bag and it may come in handy for locating controls on your camera or providing light for focusing.
A head torch is a real bonus because it keeps your hands free and shines the light where you’re looking.
If you’re going to shoot in long grass or vegetation it’s a good idea to take along a picnic blanket or piece of old sheet that you can spread on the ground to place your bag on.
That way, if anything falls out of the bag it will be caught by the sheet and not disappear into the grass.
 





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