1.4 vs. 1.8

[D-50]

I am looking at the Nikon 50mm prime 1.8 and 1.4 the 1.4 is more than double the price of the 1.8. Aside from the difference in aperature is there any difference in quality between these two. I will be shooting a rock concert in a small dark club. will 1.8 be enough to capture the band at an ISO of 400 on a D50?any examples would be great

 

[Garbz]

The 1.8 is sharper in the centre but shows poor border performance surprisingly. The 1.4 also has better lateral chromatic abberation. Also surprising really. So really the 1.4 is a better all around lens in most ways.

With concerts you'll never quite know what the lighting will be. I've been to a concert and managed to get f/2.8 1/250th at ISO400, been to another where I gave up because I couldn't get a decent picture which didn't blur at f/1.8 ISO800 :S