Exercise 5 – File Types & Sizes

1. Width of the image in pixels:2500 Pixels
2. Height of the image in pixels:2000 Pixels
3. Calculate the size of the image in Megapixels:5 Megapixels
4. What is the specified resolution of the image:30 Pixels/Inch
5. Width of the image in cm:21.17 cm
6. Height of the image in cm:16.93 cm

Select ‘File -> Save As…’ and save the image in the following formats. Name the files to clearly identify them.
After each save close the image and reopen to save to the next format. Use the Finder/File Browser to record the sizes of the files created.

1) The original .tif file:15.2 MB
2) TIF file using LZW compression:10.6 MB
3) Photoshop .psd file:15 MB
4) Jpeg file – Quality level 12:4.2 MB
5) Jpeg file – Quality level 10:1.9 MB
6) Jpeg file – Quality level 5:721 KB
7) Jpeg file – Quality level 1:442 KB
8) GIF file – 256 colours – no dithering:2.9 MB
9) GIF file – 256 colours – diffusion dither:3.5 MB
10) GIF file – 16 colours – diffusion dither:1.5 MB