If you set the recording quality to 'economy' then you are applying a lot of compression to the video and therefore small items such as text will be affected. The sharpness of the text will be lost and make it much more difficult to read. The same thing happens when you apply compression to jpeg images in an image editor, the quality goes way down. And once it's gone there is no way of getting it back as the data has been discarded. What handout are you referring to?

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