Friday, 23 February 2018

Digital File Preparation

Using Adobe Photoshop or Photoshop Elements

How to re-size a JPEG file.

All digital images will be judged at a resolution of 1400 x 1050 pixels.  The 1400 pixels is the maximum width of an image and the 1050 pixels is the maximum height of an image.  All images, whether landscape format or portrait format, must be constrained to these pixel dimensions.  Images will be shown against a black background.

  1. Open your image.
  2. Photoshop users go to Image>Image Size.  Photoshop Element users go to Image>Resize>Image size. The Image Size dialog box will appear on screen.
  3. At the bottom of the Image Size box, tick all three boxes – that’s Scale Styles, Constrain Proportions and Resample Image.  Use Bicubic (best for smooth gradients).
  4. In the Pixel Dimensions section at the top of the box, change the units to show pixels.
  5. Enter the width as 1400.  The height will automatically adjust, maintaining the proportions of the image.
    1. Before clicking OK, check the height in pixels.  If the height is more than 1050, then you need to enter 1050 in the height – this will reduce the width to less than 1400 pixels.  Click OK.

NB Several people talk about “file size” or “ppi” – none of this is relevant here, you are measuring in pixels only.

How to change the Mode of an image.

  1. From the Image menu, choose Mode.
  2. Tick on both RGB and 8 bit/Channel so that a tick appears to their left.  These may already be ticked and will not, therefore, need changing.

How to convert your image to the sRGB colour space profile.

  1. In newer versions of Photoshop go to Edit > Convert to Profile - as this produces the best result, if a change is required.  In older version of Photoshop go to Image>Mode>Convert to Profile.  The Convert to Profile dialogue box appears.  At the top of the box, the Source Space, Profile needs to be sRGB IEC61966-2.1.  If it is not, then a different profile may actually be attributed to the image.  If the Source Space is not sRGB IEC61966-2.1 then select that profile from the Destination Space, Profile drop down box and click the OK box at top right, to convert the colour space.  Click OK.
  2. In Photoshop Elements set up Color Management by going to Edit>Color Settings and select ‘Allow Me To Choose’.  That lets you choose sRGB when opening untagged files.  Alternatively, go to Image>Convert Colour Profile and choose ‘Convert To sRGB Profile’.  If that option is greyed out, you would think that the file must already be sRGB, but this is not necessarily so – you must still check the colour space when saving your image as a jpeg file – see 4. below.

How to save your image as a jpeg file.

  1. From the File menu, choose Save As.  The Save As dialog box appears.
  2. Select the folder you want to save to.  Type in your File name.  For our programme to run smoothly, this file name (excluding .jpeg) must not be longer than 24 characters – a space between words counts as a character.  Titles may be longer on the paper Titles List form but must be cut short at the 24th character for the digital file name.  The title read out will be that from the Titles List form.
  3. Check that the Format field is set to jpeg.
  4. Check the colour space is sRGB IEC61966-2.1  It’s near the bottom of that dialogue box.
  5. Click the Save button.  The jpeg options dialogue box appears.
  6. Set the amount of compression to apply to your image.  Set the quality to 12, this will ensure you will retain the quality of the image.  Make sure the Format Options is set to Baseline (“Standard”).
  7. Click OK. 

October 2014


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