I'm all about friendly advice. I just don't like the brand bashing from fanboys!
Is prime the brand of the lens? And I'm guessing that the f1.2 is just a higher quality model over the f1.4?
Like Graph said its a fixed focal lenght (they are most often referred to as prime lenses) the F number refers to the apature,the lower the F number the larger the apature and hense the faster the lense(can capture light) F1.2 can be quite expensive in primes and anything lower that F1.2 goes into stratispheric costs (not that the average person would need it). 50mm f1.4 is a good compromise as it can perform very well for most of the situations you will be likely to use it in, you will also get some exercise from it due the "manual" (walk closer or further away) focus element to using one.
no bashing from me as its all about the image produced and not about the equipment that produced it.
Canon Pimp Club #003
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