Useful Photoshop Tips and Tools
Photo Library Image Preparations

Photo Library Image preparation is essential if you want to make sure your images are accepted for sale.

I remember when I first wanted to sell my work through an image library and I was amazed at all the rules concerning the quality of the images from resolution and sizing to colour space and file saving.

However, when you consider that people who want to buy images will want the highest quality possible, then you can understand why a photo library only wants to promote the best images possible.

Below are some Photoshop tips and general advice on how to polish and prepare your images for submission.

Remember, photoshop can help make sure your images meet the requirements of these libraries but always read the specifications of the photo library you are submitting your work to, as often they may have their own special requirements that may differ.

Camera Requirements and Workflow

1. Make sure the resolution of your digital camera is large enough to meet the requirements of the library you are submitting too. The higher the resolution the bigger the prints, so some image libraries are happy to except 6mp +, while others will accept nothing less than 10mp.
2. Use a SLR camera rather than a compact, as they will produce a higher quality of image even if the resolution is the same. This is mainly due to the quality of the lens optics.
3. Shoot in RAW format, this will give you more control over the image in Photoshop.
4. Never sharpen the image before submitting to a library, as they will do any sharpening that may be required. So make sure your in-camera setting for sharpening is set to a minimum.
5. Make sure your Photoshop settings are set for the RGB (1998) colour space. Hit Ctrl+Shift+K to bring up the colour settings window and then choose Adobe RGB for the working space.

Improving Image Quality in Photoshop

Colour casts are caused when the wrong white balance setting has been used when taking the picture or that the lighting conditions were difficult and the setting was unable to remove any cast completely.

By using the Photoshop eyedropper in the raw converter window, colour casts can be adjusted to produce a much better quality image.

1. Open the Raw file in Photoshop.
2. In the Raw converter window, click on the eyedropper tool in the top left hand corner.
3. Click on an area of your image that should be a neutral grey such as concrete. The colours in the image should then adjust to a much more natural neutral tone. This process can be done several times until you are happy with the colour.

Use Levels to Enhance the Contrast and Exposure

Often images can appear a little flat and lack a full range of tones. This is simple to adjust using levels.

1. With the image on screen (not in the Raw converter window), open the levels tool by Hitting Ctl+L
2. There should be no gaps on either the left or the right of the histogram. Slide the sliders to where the histogram starts on both sides, if need be.
3. You can also use the middle slider to adjust the exposure slightly. Keep an eye on your preview image to make sure you do not over do any adjustments.

Retouching

Make sure there are no specks of dust or hairs on your image that may have been caused by dirt on the camera sensor. Any marks should be removed before submitting to a photo library.

There are two Photoshop tools that can help you remove any blemishes:

The Clone Stamp Tool - this copies pixels from one area of your picture and covers the blemish.

The healing tool - This is a similar tool but is able to blend the pixels better especially in smooth clear areas such as sky.

To use these tools see the page about removing blemishes.

Once you have removed the mark, zoom in on the area at 100% magnification to make sure that all signs of the blemish have been removed.

Interpolation and File Size

Photo libraries require images that can be printed to a high quality at large sizes. Because of cropping and ambiguity between cameras regarding mega pixels, the industry uses megabytes when they talk about the size of an image.

To check what size your final image is:

1. Open menu Image>mode and make sure both 8 bit and RGB colour are ticked.
2. Now look at the size of your file, which is indicated at the bottom of your screen in the bar that runs across your screen.

Your image library may require you to submit a 48mb file to them (check that your photo library will accept interpolation). So you must interpolate (adds pixels to your image) your image to reach this file size. To do this:

1. Open menu Image>Image size
2. Tick Constrain Proportions
3. Tick Resample Image and select Bicubic or Bicubic Smoother from the drop down menu.
4. Select Percentage in the drop down menus next to both Width and Height boxes.
5. Enter 150% into the width box. You will see the size of your file go up. Increase the percentage if required to reach your desired Mg size but do not go above 200%.

Saving Your Images

Check which file formats your photo library prefers to receive images in.

JPEG - This is really only suitable for saving RAW file to because there is a slight drop in quality. However you will be able to save more files onto a CD.

To save with this format:

1. Click menu File>Save As...
2. Select JPEG from the format menu
3. Type in name of file followed by .jpg
4. Choose where you want the file saves to and click Ok
5. Choose 12 for quality and OK

TIFF - This is a better quality file format but is a much larger file to store. There is a LZW compression format that if acceptable to the image library can be used to reduce the file size.

To save with this format:

1. Click menu File>Save As...
2. Select Tiff from the format menu
3. Type in name of file followed by .tif
4. Choose where you want the file saves to and click Ok
5. Choose LZW for image compression, IBM PC for byte order and tick 'Discard layers' and OK.

Your images should now be ready for submission to your chosen photo library.