[Steve in Pudsey]

The initial launch idents and stings were real, it was the later additions, the “lifestyle” idents that featured people, that had a CG balloon.

I don't think it was computer generated, but real footage composited over the action.  Film the balloon against a clear blue sky and chromakey out the sky is probably the basic technique.

[Spencer]

I remember hearing that the coastal ones such as Needles, Blackpool Tower and St Michael’s Mount had to have the balloon edited in, as hot air balloons aren’t allowed to fly over the sea.

Thinking about it logically, for the wind to have carried the balloon over the Needles, it’d have to be blowing away from the land. And if that’s the case, you’re not coming back!

[Stooky Bill]

The balloon was always a real one - not CG - but the setting it was seen in wasn't necessarily all real

This is a good example, it's all real but it's not a real scene - the people are sped up, the birds have been added and I think there's a bit of airbrushing on the left (either that or it just so happens they filmed it when the building that's there had been demolished for redevelopment as it was around that time)

Mod note (Frappé) - Link removed. As per rules do not embed Youtube clips that have clearly been taken from a presentation website

[AaronLancs]

The balloon was always a real one - not CG - but the setting it was seen in wasn't necessarily all real

This is a good example, it's all real but it's not a real scene - the people are sped up, the birds have been added and I think there's a bit of airbrushing on the left (either that or it just so happens they filmed it when the building that's there had been demolished for redevelopment as it was around that time)

Mod note (Frappé) - Link removed. As per rules do not embed Youtube clips that have clearly been taken from a presentation website

I'd hate to burst your - pun unintended - balloon but this page from the BBC Motion Gallery archive mention that at least one Balloon was CGed over the footage. Mind you, it was from the second tranche of idents released.

I thought something rang a bell with the later ones being CG ones.

www.ravensbourne.ac.uk 

Balloon Above St. Michaels Mount - ident (1998) | Ravensbourne University London
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  Source: www.ravensbourne.ac.uk

[Spencer]

I presume for idents like the St Michael’s Mount one, because the camera’s moving, there’d have to be some 3D motion tracking which would have required CG modelling with the texture of the balloon mapped onto it.

[AaronLancs]

Also there's another one over on the Gallery of the ident at The Angel Of The North from the same tranche that was CGed.

[Mike]

There were restrictions over the use of hot air balloons over the sea ISTR which is why some of the later ones were also CGI, that and the cost of actually inflating it, and flying it and paying the relevant people probably outstripped the budget.

[ViridianFan]

I think a few of the stings were footage of the balloon superimposed onto the landscape. The one over Edinburgh, the chalk giant and the white
Cottage. I had read somewhere too they had used footage of the balloon and superimposed that onto the landscape the balloon couldn’t fly over. 

The only ones I do w question if they are CGI are some of the special idents:
- the eclipse ident 
- the blue plant ident

I could never tell though if the 2001 Christmas ident if the balloon was CGI or not. 

The 1999 you can see it’s real footage of balloon superimposed onto the night sky, similarly the 2000 with Father Christmas dropping the present (although I’m guessing minus Christmas pudding jets) but it’s hard to tell with the 2001 as all rest is clearly CGI but you never zoom in close enough the balloon through the window.

Edit - should have been balloon not blow

[Kojak]

I think a few of the stings were footage of the blow

I think you're getting mixed up with the BBC Two Powder ident, no?

[justinh]

Some of the CG balloons were noticeably CG if you had access to high-quality renders. They certainly have a shiny, smooth appearance as compared to their surroundings. But analogue and SD was enough to cover for that.

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