Tag Archives: Image processing

Converting your image to black and white

The mill on the Rye. Taken in a local park this mill presented a wonderful opportunity to capture the early morning sunlight. However, I think it might look good in black and white. Nice contrasty subject matter makes a good conversion.

The mill on the Rye. Taken in a local park this mill presented a wonderful opportunity to capture the early morning sunlight. However, I think it might look good in black and white. Nice contrasty subject matter makes a good conversion.

Converting properly to black and white gives you greater control

I argued previously that you should not photograph your pictures in black and white. While you might get a credible picture it is not necessarily going to yield the best result. In my experience black and white, as processed by the camera, tends to be flat and lifeless. So how should you do it?

First look to your shot

Not every shot will work best in black and white (B&W). Some shots look flat and lifeless regardless of how you treat them. To get a good B&W shot try to look for pictures where the tones vary widely. Big contrasts in the colour and the texture of a subject will show big differences in the B&W ranges. Some colours convert better than others too.

The second point to look for is to shoot in RAW. If you are shooting with *.jpg files you will restrict the ability to post-process your shot effectively afterwards. The whole point of shooting in colour and converting to B&W is that you are able to fully manipulate the process to draw out the best that B&W can offer. RAW provides the depth of tones with which you can do that.

The conversion to Black and White

Converting to B&W is not difficult. However, you need to know the most effective process. In most editing applications there are two methods. These are…

Photoshop: [ Click – Image menu | Adjustments | Desaturate ] Or [ Hold down Shift + Control + U ]
All colours resolve to a grey colour if mixed correctly with another colour. The tendency to create a grey from a specific colour is to desaturate it. However, all colours will resolve into the same grey if it were not for variations in brightness/lightness. The standard desaturation option in image editors is a program for reducing the colours to greys leaving the variations in brightness to create the grey tones. The ‘Desaturate’ option is limited. It does the same as a camera when shooting in black and white. Using this option you have no control over the conversion.

Photoshop: [ Click – Image Layer | New Adjustment Layer | Black & White ]
This option allows you full control over the colour brightness before the conversion to grey. As the brightness determines the grey tones this gives you the opportunity to vary the intensity of the grey in the final conversion. In Adobe PhotoShop you are presented with a dialogue box that provides a slider for each available colour. As you slide them back and forth you will see the grey tones change. These changes are what allows you to adjust the strength and depth of the blacks and whites in your picture. The adjustment brings out subtle variations to emphasis the depth and three dimensionality of the picture. In addition, colours, tones and brightness/lightness varies for every picture. Using the sliders you will be able to adjust these variables to suite your scene. This is something your camera or your ‘Desaturate’ option cannot do. As a result you will be able to create a subtle variation that brings out the best in your picture.

Although I have used Adobe PhotoShop as the example here most applications have two options for the creation of B&W pictures. You can access your help files to see which you want. The most effective is the adjustment option – so look for a term that describes that sort of control.

To see what the difference is between the methods I include two B&W conversions of the picture above. The first uses the ‘Desaturate’ version…

The Mill on the Rye - Desaturated version. Not bad, but a little flat

The Mill on the Rye – Desaturated version. Not bad, but a little flat

The second picture uses the ‘Adjustment’ method. The colours have been adjusted to create a greater contrast in the black and white range of the picture. This gives a better grey tonality and creates a greater sense of depth in the picture…
The Mill on the Rye - created using the 'Adjustment' process for converting to black and white.

The Mill on the Rye – created using the ‘Adjustment’ process for converting to black and white. There is a greater range of tones.

EXIF Data – Understanding Your Shots

Image files hold hidden data about the file and the image itself

'The Kick' - an image file has EXIF data stored inside

'The Kick' - image files store EXIF data about the file itself. See below for data in this image file.
Make - Canon Model - Canon EOS 5D Mark II
Orientation - Top left
DateTime - 2011:04:09 11:04:14
Artist - Damon Guy (Netkonnexion)
Copyright - Photokonnexion 2012
ExposureTime - 1/640 seconds
ISOSpeedRatings - 100
ApertureValue - F 4.00
Flash - Flash not fired
FocalLength - 280 mm
ExposureMode - Manual
White Balance - Manual
SceneCaptureType - Standard

In your image files is information about your photos. The aperture value, shutter speed and ISO settings are three important pieces of data. However, there is a whole lot more.

The stored data is called EXIF. It stands for Exchangeable Image File Format. The EXIF data is stored by a number of image formats including JPEG, JPG, Tiff, RIFF and WAV files. It’s also found in many camera RAW formats. EXIF data is not supported by JPEG2000, PNG or GIF image formats.

EXIF is a great source of information. Once you understand it you can find out how the shot was make. Look at images by other people. It is an insight into the way they made a that image. When you see a picture you like view the EXIF data. You can tell from the values what settings were for that shot. Bear in mind EXIF data can be removed from a photo. So, it may not always be there.

EXIF data is a great learning aid. You can look at the EXIF data in your own image files. Check out the settings at the time your shot was taken. If the shot did not go well you can analyse what went wrong. Next time you will know better.

Getting the EXIF data

EXIF data is available in a number of ways. You can get it from most image editors when you open your file. Irfanview, an image viewer and editor, has a dialogue box for reading and copying EXIF {press ‘altgr’ & ‘e’ together}. Photoshop and Elements have read and edit tools for EXIF data. GIMP External link - opens new tab/page has the same facility. To use these editors to see EXIF data consult the help pages for your version.
More after the jump…

You can also get the EXIF data using Windows Explorer…

  • Windows XP: Right click the image file; left click “Properties”; click the ‘Summary tab’; click the ‘Advanced button’
  • Windows Vista/Windows 7: Right click the image file; left click “Properties”; click the ‘Details tab’
  • Mac OS X: view EXIF data with ‘Finder’. Do a ‘Get Info’ on a file; expand the ‘More Info’ section

In some versions of Windows you can edit the EXIF data as well as read it. However, the data about the file itself remains in the file. You can remove the private data and edit the camera data. Although you can edit the information in Windows XP it is inadvisable as a bug sometimes corrupts the data in JPEG/JPG files.

Editing your EXIF data

Data from EXIF files includes camera settings data stored when the shot was taken. There is also copyright data you can edit in-camera or add while editing.

Being able to edit your EXIF file is useful. You might want to put extra data into the file that’s not collected by your camera. For example you may want to save contact and copyright details. Or, you might want to remove some of the data. Some photographers do not publish EXIF data to prevent publishing information about the shot.

Not all cameras support all fields. The EXIF format is supported by at least the Japanese camera makers. There are many other cameras supported too.

EXIF data – many ways to use it

There are many ways to use the EXIF information. The first stage is to look at the data in your own image files.

You can also set up your camera to create EXIF data. It will store your copyright information and other data in your images when you make a photo. You can also add other types of data beyond the pure EXIF data. See your camera manual for instructions.

Have fun with your EXIF data!