Canon 40mm vs 50mm f/1.4

[pensive tomato]

I've seen many comparisons of the shorty forty and the nifty fifty, but not much info bringing the 50mm f/1.4 into the mix. I know of the obvious difference in focal length and the 2-stop advantage of the 50mm. I've owned the 50mm for almost two years (my first prime), yet it never felt "right" even after I moved to FF with the 6D. I think going a bit wider may be the answer. So I'm asking for clarification on the following from all the more experienced minds around:

1) How do these lenses compare on sharpness f/2.8 through f/8?
2) Is there any improvement on AF speed/accuracy on the 40mm?
3) Any thoughts on FTM functionality and motor noise (I've never used an STM lens, yet I've found the 50mm's USM implementation lacking)?

 

[Mt Spokane Photography]

If your 50mm does not seem right, have it checked at Canon. It does not have true USM, but is plenty fast to focus, faster than most lenses simply because it does not have to move the barrel very far. The focus mechanism can be damaged and slow down the lens focusing. It still appears to be working, but is slow.

The 40mm is a very simple lens. It is slower to focus, but quieter. It is faster to focus on cameras optimized for STM, but there are no FF cameras that are.

As far as sharpness, that's a term that misleads a lot of people, we all use it. I suspect you refer to the overall IQ. For example, a lens image can look very sharp because of high contrast and low chromatic aberrations even though its measured resolution is not that high.

http://www.cambridgeincolour.com/tutorials/sharpness.htm

For the price, the 40mm is a super buy, and it produces beautiful images, even at f/2.8

 

[Rienzphotoz]

If your 50mm does not seem right, have it checked at Canon. It does not have true USM, but is plenty fast to focus, faster than most lenses simply because it does not have to move the barrel very far. The focus mechanism can be damaged and slow down the lens focusing. It still appears to be working, but is slow.

The 40mm is a very simple lens. It is slower to focus, but quieter. It is faster to focus on cameras optimized for STM, but there are no FF cameras that are.

As far as sharpness, that's a term that misleads a lot of people, we all use it. I suspect you refer to the overall IQ. For example, a lens image can look very sharp because of high contrast and low chromatic aberrations even though its measured resolution is not that high.

http://www.cambridgeincolour.com/tutorials/sharpness.htm

For the price, the 40mm is a super buy, and it produces beautiful images, even at f/2.8

+1

 

[skfla]

Pensive tomato, Dude the 40mm is $80 refurbished at Canon USA right now. Probably sold out but if not, just pick one up. For that price you can do your own comparsions & then use it as a body cap-or paperweight!- if you don't like it (or just stick it on your back up or sell to friend). Good luck! sk

FYI, The wider angle than the 50mm is nice & the colors seem better than on Canon's old 35mm f/2 (somewhat comparable price range). I do like using it on my 5D2 for fun but not when I'm shooting anything serious. & the focal length on either of my back ups (both are crop sensor) is not really very functional.

 

[pensive tomato]

Mt. Spokane, I may take your advise and send my 50 to Canon. It's always been slower and less accurate (AF) than my 85 and 100 primes. I'd blamed it on the older lens design and my own skills, but there may be something else going on.

skla, you're right in that the pancake is an easy buy and perhaps worth a shoot.

Thank you all for your comments on IQ and the healthy reminder on keeping lens characteristics straight.

 

[Dylan777]

I used to own 50 f1.4...AF speed is better than current 40mm. @ f2.8 50mm is very sharp. Same for 40mm. I don't like the AF noise on 40mm. It feels cheap, but hey, it's $150 lens cap . 40mm is great lens if you want to go light.

The new Sigma 35mm f1.4 is not a bad idea in term of sharpness @ wide open.

 

[kennephoto]

I have the 50 1.2L and the 40 2.8 and I used to have the 50 1.8 I and II I love my pancake so much. It's my eveyday lens on my 5D mark II it's image quality is superp mine is very quiet focus is quick. I like the bokeh I can get with it. It keeps up when I am photographing my cat. It's amazing and so much fun to use on my full frame camera! I just leave it at 2.8 and shoot away! I've used the 50 1.4 in the store but it didn't do anything for me. I'd rather have the discreetness of the pancake.

 

[pdirestajr]

I also like that the 40mm has a closer MFD.

 

[florianbieler.de]

Quite a bit difficult to compare a 2.8 lens to a 1.4 lens. That's two stops. The 40 basically is a real bargain, offers great quality for its size and weight and just has style somehow. I owned it for some weeks and was quite satisfied with its performance. Of course if you own a Sigma 35 1.4 like me, you won't put on such a 40 2.8 that often, except if you want to go ultra light.

 

[rihanishtiaq]

The STM lenses Can be used to do Continuous auto focus during video shooting.. but you will need A canon body having that compatibility like the t4i

 

[bahula]

Given how much overlap you have with the 24-105 and 17-40, I'd go for the 40 and it call it a day. It's a great lens before you consider how cheap it is and it's just fun to use. You should have a pretty good idea of what primes would be useful to you with the range covered by your zooms- if your budget allows for it and you know it'll see good use, the Sigma 35 (as mentioned above) is better than the 40 and very much "worth it." I'd probably skip the 40 if you're going to pick up the Sigma unless you have need for a light, unimposing lens.

 

[Hector1970]

I have both lens but rarely use the 40mm. That's because I love the 50mm 1.4. It often gets a bad wrap here but I just love the photos I get with it. Maybe I have a good copy (or good +\- tolerance matching with the camera). The 40mm is good but lacks a specialness. I like shallow depth of field. STM is not of much use without a body that can use it. My lens collection has grown but the 50mm always comes along.

 

[RLPhoto]

The 50mm 1.4 is decent. It's not great but @ 2.8, It's IQ is nearly identical to the 40mm. Plus, you get those Two stops when you need them.

 

[silversurfer96]

I have both... For the quality it delivers, can't go wrong with the prices on either one. I love the light weight of the 40mm. Essentially, it's a P&S DSLR.

 

[LOALTD]

I have both lens but rarely use the 40mm. That's because I love the 50mm 1.4. It often gets a bad wrap here but I just love the photos I get with it. Maybe I have a good copy (or good +\- tolerance matching with the camera). The 40mm is good but lacks a specialness. I like shallow depth of field. STM is not of much use without a body that can use it. My lens collection has grown but the 50mm always comes along.

Amen to that, 90% of my photos are shot with the 50/1.4

It’s odd that it get such a bad rap on here…it’s nearly 5X cheaper than the 24-70 II (which is worshipped) and it’s just as sharp if not sharper, and can give you two more stops of light when you need it.

I wish it had IS though ;D