On Screen Text

Can i kick off a discussion.
Are there any guidlines givin out for any channel, on the best sizes for text onscreen.
How small can you go and they will still be readable? How big is too big? Are there any colours that simply dont work (like web safe colours)
When they change from 4x3 to 16x9, does this send the text squiffy?
Should onscreen text have a small edge of, say, black to stop colour bleed - or does that not matter in this day and age.
If you wanted a shadow behind the text, are they guidlines on best practice on that.
And how transparent can you go.

?????
If there are any guidelines, sky has obviously ignored them all with their recent facelift!

ste

The only guidelines would be in-house, unless the 'dogs' were adveritsments I should think. I suppose the ITV could come into it if there was a really big ITV etc.. logo in the corner of the screen that covered up peoples faces.

On-screen text doesn't need the black boundaries around it, just some way of guaranteeing that the text is visible against any background. That's generally done by bringing up a coloured background behind the text, or as you say putting a black shadow behind it.

There aren't any guidelines, but obviously there comes a point where on-screen text starts to look ridiculous when it's too big. On a widescreen image of course the text has to be a certain distance from the left and right sides of the screen, to stop it disappearing off the sides on non-w/s TVs.

(Edited by jason at 9:47 am on Feb. 6, 2002)

This depends primarily on the type of equipment used to generate the captions.

There are basically three ways of overlaying text onto a video image:

1. Spot colour
2. Spot colour with keyline
3. Anti-alias

(1) Are captions that are single-colour only (usually white) and are generated by the older/cheaper devices such as the Chiron, and also some versions of Quantel Cypher. There is no outline because only one colour can be used. Sometimes, this is also the case when using equipment that can use more than one colour, but is keyed-in to the picture using a 'luma-key' channel. This is where there are only two video levels detected - black and peak white. Anything in-between is rounded up to black or white.

(2) These are as (1), but using a setting (usually on the mixing desk but sometimes on the character generator) to add a black outline around the edge. In the days where almost all text was 'luma-keyed' onto the background, if the background was light, or indeed, white, this setting would have to be turned on in order to make it readable. Just about every caption on trailers in the mid-late 80s and early 90s was done this way, especially on the BBC. The outline was usually generated by the mixing desk itself rather than the character generator.

(3) These are captions generated by equipment that uses various shades of grey (or in-betweens of the text colour) around the edges of the lettering. Some versions of Microsoft Windows have a similar feature, labelled 'Smooth edges of screen fonts'. These are keyed-into the background image in various ways, and whether you get an outline or not depends on the abilities of the mixing desk and associated equipment in the studio where the caption is generated. You could have 'soft-edge' where the text is basically 'superimposed' or 'double-exposed' on the image, or 'hard-edge' where anything 'non-black (or non-background)' is substituted with the background image. Depending on how well it detects the anti-aliased edging, you may get differing amounts of black (or dark) outline around the anti-aliasing.

BBC Fault captions would appear to be type (3), although the Nations do have different ways of doing this. BBC Network have readily created slides that say 'We apologise for the break in this programe...' and similar, that were composited on a Quantel Harry or similar device (or perhaps in a digital paint package) where the text has been 'burned in' to the image - i.e. the balloon backdrop has been imported as a still image file (hence why it doesn't animate) and the text has been added to it, and the composite has been saved as an image.

The Nations, however, use a blank balloon background and 'key in' captions live from a generator, using anti-aliasing and hard-edging. BBC Northern Ireland's break captions, for instance, show a markedly different 'kerning' (letter spacing) and a slight black outline around the edges of the lettering. However, the lettering looks slightly smarter - as if it's generated by a word processor or DTP package.