I will attempt to answer Walrus' question about why the usage of the CGI raised a red flag to me. First, there is nothing wrong with using CGI to illustrate something which is occurring, as long as the viewer can reasonably ascertain the imagery is computer generated. The glacier scenery is harmless because it represents reality. Nothing is going on there in that scene except a view of glaciers. The scenery is beautiful, and maybe even enhanced using the computer. Nothing wrong with that at all. So far so good.
I have not seen Al Gore's movie, so I have not read the credits. I have tried to locate the credits using Google unsuccessfully. It likely is a moot point whether permission was granted to place the scenery, as it is only a few seconds of footage, does not damage the movie from which it was borrowed, and the messages of both movies are similar. As was pointed out, one of the (original) movies' directors was delighted that scene was included. There probably is no lawsuit to worry about because the message of both movies are in agreement.
All in all, that CGI shot in and of itself is not a big deal. As I said, I have not seen the movie credits, so there may well be mention of the borrowed segment. However that mention should be there if it is not, and this is why.
It used to be that it was easy to tell if something was a special effect. Computer generated imagery is so good nowadays that it is hard to tell what is real and what is not. I watched a show on tv a couple months ago which was about scientists in a sailboat time machine. They started in modern times and went further back in time on each successive voyage, stopping awhile during certain time periods and diving underwater with cameras. I started watching this show about a half-hour into the action. To make a long story short, I was completely fooled that what I was watching wasn't real, until it was obvious the sea creatures were computer generated. In other words, the CGI was so good (along with the dialog) I thought the giant sharks these scientists were "filming" were real. I thought the show I was watching was modern day reality. It wasn't until they started diving amongst giant crocodile-like creatures that I began to realize something was amiss. I was completely fooled for about an hour into the show (having come in after it had started and not knowing the nature of the movie.) Needless to say, this was a little disconcerting and confusing to me because I thought they were filming the real thing. I thought I was watching real footage of prehistoric creatures somehow existing today. Some new and fantastic discovery being filmed. Once I realized it was CGI, I couldn't believe that for awhile I thought what I was watching was real. It was that good.
Here is the problem as I see it. This day and age it is pretty easy to fool people with CGI. There is a danger it will work its way into news clips, and I believe it has already been done with photography in the newspaper. Of course we all know about photoshop. The bottom line is, folks are wary of this and become rightfully upset whenever it is exposed being used by trusted news sources.
There is no real harm done by the short CGI segment in Gore's movie if it is properly identified as being CGI. The harm would come if it is not identified as being CGI, presented as real. Not so much from the harmless clip segment of a glacier just being there, but from the idea that CGI was used for that segment and could have been used in other parts of the movie too. And then the question arises, which other parts might it have been used in? While not intentionally lying perhaps, a seeming harmless and minor oversight on the part of a director or whoever is responsible for movie credits and pertinent information, could undermine a movies' trustworthiness. It could potentially call in question source credentials required of an educational film presented as a documentary. Gore's movie is designed to move people to action. Naturally it is under close scrutiny.
If the credits mention the presence of CGI, then any concerns of visual manipulation and, by extension, possible misinformation would be properly addressed and not an issue. If the credits are not there, it is an oversight which should be tended to.
Les
