Deciding between the 50 1.4 and the 85 1.8:

I´ve got some questions:

a) Which one hast the better optical quality at the same aperture belonging sharpness, contrast, CA, Vignetting and Distortion?

b) Is the 1.4 useable at the 50 1.4? Or is it really unsharp then?

c) Is the AF of the 85mm really much faster, more precise and unerring?

d) Are the two Fix Focal Lenses better than my Tamron 28-75 2.8 at same apertures?

e) Is the 50 1.4 really mechanically sensitive? I heard that the USM breaks quite often...


Well, the most important thing for me is the optical quality and i can´t decide between the two lenses...

Without knowing anything about you and your shooting preferences, I'd say get the 50 if you have a crop body and the 85 if you have a full frame. I think the optical quality of the 85 is a little better.

I have both these lenses and use them on both 1.3 crop and FF bodies. I think....and I stress the word "think", I agree with what Chris says about the optical quality being maybe better on the 85. I have never really done side by side testing to confirm this, but it's just a bit of my gut feeling. I do thing the 85 has a more pleasing bokeh.
They are both good lenses in my opinion, and I use and will keep both.

Considering you have the 28-75, what is your focal length preference? That would be the ideal way to decide.

I have both, the 50 & the 85, and I use the 50 more. On the other hand I think the 85 has better optical quality as well as built quality, the 50 is quite usable at 1.4.

tkbslc wrote in post #10720817
Considering you have the 28-75, what is your focal length preference? That would be the ideal way to decide.

Well that´s not the matter, as i could complete my available focal lengths.

stephan902 wrote in post #10721031
Well that´s not the matter, as i could complete my available focal lengths.

How can focal length not matter? Those are very different focal lengths. Regardless, that is still my advice. Decide whether 50mm or 85mm suits your style and needs more appropriately and then you have chosen your lens.

i've had both and i like my 50 1.4 way less prone to ca... at least my copies

I love my 85 1.8, my favorite portrait lens. The 50 1.4 is nice, but not what I pick up for portraits most of the time. Depending on what conditions you are using the lens, the 50 has a tendency to hunt in low light situations.

I prefer the 85/1.5 as it's AF is better in all regards, faster, a bit more accurate, and a lot more resilient to damage. It's sharper than the Tamron at any comparable aperture. The problem with the 85/1.8 is CA especially wide open with high contrast areas.

I've had a couple Canon 50/1.4 and the AF died after someone's shoulder bumped into the front element. Not a fan of it for other reasons as well and I'd recommend the Sigma 50/1.4 over it, even if you have to send it in for calibration.

Do what I did: rent them both and then decide.

I went for the 85 based on preferred FL, optical, and build quality.

I have the 85f1.8 and a Sigma 50f2.8 macro, so I can't comment on the use of the 50f1.4 wide open. Once you get to f2.8, most 50 mm lenses will be alike in image quality.
The 50 mm on a crop gives you a field of view that is comparable to 80mm on film or full frame. I compared the field of view of my Minolta 85f1.7 on a film body and the 50 mm Sigma on a crop, and couldn't tell them apart.
The 85 is a very nice lens outside. It is sharp and has very fast focus. Inside, it will do for head shots, or head and shoulders in a large space. It will do more in a pretty large space. It needs a high shutter speed, since the field of view is like a 135 on film or full frame.
A fast 50 will do more for you indoors in most cases. I was concerned about the frequent reports of problems on the 50f1.4 and that is why I got the Sigma macro lens.
I use the 35f2 for candids in natural light, and wouldn't mind a faster version. F2 will work in most cases, especially with the T2i. Most reports are that the 50f1.4 will do fine at f2.

http://www.the-digital-picture.com/Reviews/

good reviews on lenses...