A Thank You and Apology

For me the best use of CGI is always when you have to be told they used a CGI effect*. The best example was The Dark Knight, where they only had two or three CGI shots in the entire film. The only two I know of where the Bat Pod comes out of the wrecked Tumbler, a scene that they realised they could not do with practical effects**. The second was in digitally removing the huge pole that flipped the truck in a slightly later scene.

In other cases CGI is the only option, the Spiderman films had to use CGI for the web-swinging because no human could have done those scenes without loosing an arm. Of course Spiderman is a comic book character who lends himself well to such 'over the top' effects by his very nature and the 'reality' in which he exists. You could not really get away with the same sort of effects with the Punisher even though both technically exist in the same universe.

This is in a way the 'realism' that can be lost by writers/directors who overuse CGI, as in concentrating on showing what they had in mind rather than thinking things through in terms of what really needs to or should be shown. In fairness they are almost certainly being affected by the studios demanding that they top the 'action' of the last successful film. (Rather as all the studios jumped on the 3D bandwagon Avatar started). The 'universe' in which some films are set lends itself well to heavy (and overt) use of CGI, since those worlds are clearly more fantastical than our own. Star Wars, Star Trek***, Spiderman and Superman are the first four such settings that spring to mind.
Other worlds don't lend themselves well to such use of CGI, as they are meant to have a high degree of 'reality' in them. Batman is the prime example here****, and I'd probably add Captain America (at least the first film) to this as well for the most part.

When you have settings or characters who fall between the two extremes you need to be very careful as to how you use the CGI. I think here The Avengers was a good example as to how you can get it right, as the story (and of course the proceeding five films in what is turning into a bigger franchise than Star Wars) manages to flow into the CGI heavy scenes in a more natural way. If you look at the film closely you'll notice that there is only one clear occasion when one of the characters was rendered entirely in CGI during a fight***** - Although the Hulk was CGI, a comment which is a no brainer, this was an effect placed on top of the actor - who was on set wearing a strange and humiliating suit. He probably could have just worn an orange jumpsuit, but hey...directors should be allowed to have a little fun with actors....

(*I'm excluding green screen shots for backgrounds ect, as well as digitally removing wires and the like from practical effect shots. Such effects can be done using other techniques, but CGI is cheaper, faster and better than the alternatives.)

(**They did try to work out how to do this shot as a practical effect, but realised it would be too complex and expensive a build for the second or so it would be on screen. So they went with CGI as a viable alternative.)

(***Not just Wars and Trek, but any sci-fi that requires large vehicles to be on screen. Making a model spacecraft that is movie quality can take six months or more and cost in excess of $250,000. And then you are limited as to what angles you can film the model from, as well as praying that no idiot drops the model or runs the camera into it - Or in the case of the model of the USS Excelsior glues extra parts onto the model that you can't remove without wrecking the original 'hull'.)

(****It is going to be interesting to see how they are going to balance the 'realistic' nature of Batman with the CGI heavy 'fantasy' of Superman and Wonder Woman in the upcoming film.
Yes, you heard me right - Wonder Woman is in the film as well as Bat's and Supes - or at least the character has apparently been cast. Personally I'd rather see a Wonder Woman film first, but I guess they were nervous about making one given that she hasn't appeared in a live action anything since the 1970's and the big budget Green Lantern film tanked.)

(*****The minute long sequence that follows the action from one Avenger to the next near the end contains an entirely CGI Captain America. That or the actor is capable of jumping eight feet in the air and performing a spin kick twice without touching the ground.)

May The Farce Be With You.