Originally Posted by coupekid
Specifically the one i am looking at is the 50mm f1.8, at around 70-80 pounds.
However, I have also seen an F1.4 lens but this is well over 200pounds.
So my question is this, what is the difference, and will the f1.8 be good enough to compliment my extension tubes, and for portrait photography, or should i spend the extra?
I had the 1.8 and then got the 1.4 for a few reasons.
I never liked the awful narrow manual focus ring that's right on the end of the lens. If you use the square 'Cokin' type filters you can't even get to it with the 'filter holder' on. The 1.4 has a lovely big wide ftm ring.
Also, out of focus highlights can be very bad, being pentagon shaped, as Ian said.
It is however a very sharp lens although not great wide open. It's not 'usm' but there's really little in it focus speed wise compared to the 1.4.
My 1.4 is much, much sharper wide open than the 1.8 but by F11 they are the same.
If I started again I would certainly get the 1.4 knowing what I know now. If you don't you will always be wanting one, like I was.