What was your favorite regional ITV station growing up?

The film ones in the 50s and 60s were used as video stabilisation measure. Early b/w TV sets lacked what's called 'DC Restoration' circuitry. What that meant was the picture when supposed to be black, was never jet black, but a washed out grey. Also, there would be picture instability, (due to poor EHT regulation) if the signal changed instantly from white to black (or vice versa). To avoid this impairing the first second or so of an advert, an animation was inserted before and between each ad, to gently build up the picture brightness.

Break bumpers were a novel feature for me in 1991 in tyne tees land, on holiday in Whitley Bay. But, I seem to recall Tyne Tees, in 1988, used a break bumper first used in the late 1970s!

Not quite, it was an old animation they used for promos in the late 70s. Still looked very odd in 1990 (not 88 ). I suspect it was probably an engineer tinkering with the kit one afternoon, and it just stuck - no branding exercise would have resulted in that...

That or management at the company went down south one day and came back saying "we should have one of those" but didn't provide any budget for it 😁

LWT brought in a break bumper c. 1984 (the logo in the red/orange/yellow gradiented stripey circle spinning backwards), with a replacement as part of the 1986 package (like the Solari ident, but with the vertical blinds wiping the entire logo off-screen). The 1989 'generic' one was kept right up until September 1996!

In the days when break bumpers were known in the trade as 'opticals', they were more common than you'd think. The Southern star has already been mentioned:

- ATV had one in the early part of the colour era where the two 'eyes' merged into one and then 'zoom'ed out

- One which I think a few stations used had a St Andrew's cross effect which wiped between black and white - I've seen it in use on STV off-airs and they kept it until c. 1983

- Thames also had one until c.1975 where the horizontal wipe used in its first idents opened to a blank screen

- ...and, lest we forget, the Rediffusion spinning adastral - hence why it became shorthand for "vintage adverts", real or parody

'Opticals', I guess, fell out-of-fashion as more adverts became sourced from videotape, so almost all companies just stuck with black space into commercial breaks.

Some companies also used 'flashes' between any ads played off telecine - e.g. the LWT squares, the Westward/Channel revolving hexagon - that idea was revived on *some* region's breaks between 2002 and 2004 with the blue/yellow squares.

I'm sure in the early 70s LWT had one, a series of white squares, each one getting larger, until the final one filled the screen ?

I think they were quite common in the 60s and 70s, I think at least partly they served some technical purpose with the old telecine machines and the quick cutting to and from adverts that could have caused picture disturbance, I think? Stopped being an issue once adverts started being played off tape which is likely why they'd vanished in most places by the 80s. I have seen a late 70s LWT ad break which has the flashes before film adverts, but not before the couple of VT sourced ads in the break.

Edit: Notice MarkyMark has covered this above.

Ah yes, my memory of 40 years ago has got confused there!

That one always makes me think of It'll Never Work and their spoof adverts. They'd have a voice shouting "commercial break" over it.

It wasn't anything related to the broadcaster's end of things, although it might have been helpful for the transmitter output klystrons ?

It was to allow for inadequateness in domestic TV receivers (professional monitors didn't suffer, because they had the necessary stabilisation circuitry) By the time colour tellies arrived in the late 60s, they were fine, because they needed to be ! b/w tellies even into the 80s, and until anybody stopped making them, still didn't usually have a DC clamp

Although the Pye/Philips CT200s still had an unfortunate tendency to balloon and bounce/flicker when changing from dark to light images! I was unfortunate enough to have one of these into the early 1990s, damn thing refused to die. Eventually the tuner box fell apart and I was unable to source a replacement cheaply so it went to the tip. Shame really as despite its general crapness it actually gave the Japanese TVs a run for their money in reliability terms.

'Ballooning' of pictures was a feature to some extent or other of CRT tellies; consigned to the past along with geometry, colour convergence, and purity issues, thanks to the modern miracle of flat screens, (though getting inky blacks again took a while still, arguably not really until HDR came along ?)

True but the Pye was especially bad for it. Very poor power regulation was the attributed cause. The chassis was an attempt to match the 1970s Sanyos and Hitachis on price but performance suffered greatly as a result.