When would you use a small shutter opening angle?

[slashmaster]

I just realized the cam I have now only has a 170 degree shutter and the one I had before had 220. So thought I'd ask when is it best to use something with a smaller opening? I'm guessing my picture won't be as sharp but will be better for action shots? Is it common for people to take a camera apart and cut a shutter a little wider?

[Angus]

The smaller shutter angle means a shorter exposure. The one disadvantage is that you need more light to expose your shot (not good for low light filming in the days of K40) but it will give sharper pictures and better rendition of fast moving objects.

My first sound camera was a Chinon 12SM which has either a 150 or 160 degree shutter, I used it to film a couple of sportscar races and it did a good job - better than an XL type camera with 220 or 230 degree shutter. It also gave super sharp images when making more 'normal' shots, but it had poor low light performance despite the f1.2 lens.

So, use it when you have sufficient light - probably easier these days with 100D and the negative films than in the good old days of K40. All assuming you don't want to blur motion a lot.