50/1.8 vs 1.4

[Jay Todd]

Is there an obvious image quality difference to justify the $200 difference, or should I hang on to my 1.8II?

More directly, I do shoot mostly wide open, and wondered if the 8-blades give a better look than the 5 on the 1.8 for out-of-focus...again with enough defference to justify cost.

[Belmondo]

The 1.4 is 1 f-stop faster.
That's obvious.

The difference in optical quality is very slight, getting squarely into the 'so what' factor. I have done side-by-side comparisons of the two lenses, and in most cases I really can't tell the difference. Build quality is a lot better on the f/1.4, however. Over time, this will likely be important.

[Scottes]

But Tom, over time you could buy 4 of the 1.8s for the price of a single 1.4....

Glad I bought a 1.8...

[Guillermo Freige]

Sorry, but the 1.4 isn't a stop faster, only 2/3 stop faster, but the 1.8 below f/2.2 is very soft, so probably the 1.4 has a more "usable" 1.8. Also the 1.4 has a focusing scale and a metallic build, compared to the plastic 1.8.
Said that, I've tempted by an 1.4, but finally bought an 1.8, and I'm very happy :)

[Belmondo]

No arguement there. This situation is unique with these two lenses, although also exists to a lesser degree with the 70-200 f/4L and f/2.8L (non-IS). In that case, the cost of one f-stop is just about double, but the build quality is equivalent.

[Belmondo]

Sorry, but the 1.4 isn't a stop faster, only 2/3 stop faster

I stand corrected. Thanks.

[scottbergerphoto]

You can compare the optical quality of the two at www.photodo.com under products. They are virtually equivalent in optical quality by MTF tests. The 1.4 is built better, is a litttle faster, and has a more pleasing bokeh(talked about on www.luminous-landscape.com ). Whether those things are worth the money to you is a personal choice.
Regards,
Scott

[Tom W]

From my own anecdotal experience, I've found the 1.4 to be just a little sharper in the range below about f/4.0 - that is, the 1.4 appears to be as sharp at f/1.4 as the 1.8 is wide open at f/1.8. Like most lenses, they're a little softer wide open, but the 1.4 sharpens up a tad earlier as you stop down. So if you're really critical about low-light, this is an advantage albeit a small one.

[jfretless]

I just picked up the 1.4. Shooting extremely low light concerts, the extra 2/3rds will be invaluable. Everybody talks about sharpness, but in situations were you need to shoot wide open, at that point, sharpness is not the main issue, getting a usable shot is. If you want to talk about sharpness, how about the difference between a motion stopping shutter speed versus a subject moving blur. I think that's where the price difference is justified.

Correct me if I'm completely wrong, but in a case where you a have a lens that is a full stop faster, wouldn't you be able to drop your iso setting from say, 3200 to 1600 at the same exposure settings? That would be huge difference.

John

[MarkH]

Correct me if I'm completely wrong, but in a case where you a have a lens that is a full stop faster, wouldn't you be able to drop your iso setting from say, 3200 to 1600 at the same exposure settings? That would be huge difference.

John

Sounds right to me.

I bought the 50 f1.8, I am happy with my decision. To me the f1.4 was too expensive, I don't use primes much and the f1.8 gives me the sharp portrait lens with wide aperture and shallow DoF when I want that. If I used the 50mm a lot then maybe it would be worth getting the better constructed lens with distance scale and metal mount.

The real question:
Will you use the lens enough to make it worth spending the extra on the 50 f1.4 for the better build, better bokeh, distance scale, wider aperture, etc.

The out-of-focus question is one I have seen on www.luminous-landscape.com and I remember they said that the 8-blades did produce more pleasing Bokeh. Once again, if you use this lens a lot with wide aperture and the Bokeh matters to you then it may be worth spending the money on the f1.4.

My opinion:
The 50 f1.8 is a good lens that is well worth the very reasonable price.
The 50 f1.4 is an even better lens that is worth the cost to those that use a 50mm lens a lot and will get the value out of this lens.