[Blue]

If you shot the same subject under teh same conditions wide open at f/1.2 and f/1.4 with, say, their "A" versions, printed them big (assuming both are in focus, exposed properly, etc), and laid down a series for a Coke vs. Pepsi face-off, you'd probably see no difference in practical viewing unless someone knows how to count aperture blades (9 for 1.2, 8 for 1.4). Good luck with that.

For aesthetic performance, no difference.

As for the comments about newbies getting a fast fifty. Absolutely. Great advice. It gets people moving their feet and allows for greater DOF and isolation opportunities that are the bread and butter of good photography.

This was a discussion from 7 months ago. The thread was brought back by the question on whether the f1.2 lens openyourap was cost effective to have some repairs done to it.

As far as the difference between an A 50mm f1.4 and an A 50mm f1.2, the big difference is at wide open. Also, due to the physical size differences in the elements, there are possible other things going on with differences in optical vignetting and natural vignetting (aka light fall off) but whether or not the differences can be noticed, it would come down to the characteristics of the shot and the test you describe is very vanilla and unlikely to push the lens for aesthetic differences. I can tell you with certainty that my FA 50/1.4 and A 50/1.2 are different beasts during night shooting.

Edit: Here are a couple of hand held shots from them.

1/13, f1.2 ISO 800 & K200d

1/60, f1.4 ISO 1600 & K20d

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Last edited by Blue; 07-21-2010 at 11:59 AM.

[Pentaxor]

If you shot the same subject under teh same conditions wide open at f/1.2 and f/1.4 with, say, their "A" versions, printed them big (assuming both are in focus, exposed properly, etc), and laid down a series for a Coke vs. Pepsi face-off, you'd probably see no difference in practical viewing unless someone knows how to count aperture blades (9 for 1.2, 8 for 1.4). Good luck with that.

For aesthetic performance, no difference.

As for the comments about newbies getting a fast fifty. Absolutely. Great advice. It gets people moving their feet and allows for greater DOF and isolation opportunities that are the bread and butter of good photography.

this is basically the wrong impression that some people have with the 1.2. having handled both lenses, the difference is night and day in terms of practical and aesthetic performance.

to those who think that the half-stop advantage of the 1.2 to the 1.4 does not show any relevant difference, you are wrong.
the light transmission of the 1.2 is so strong that would make the 1.4 shot look like underexposed by more than just a half-stop. this advantage is very practical and evident in lowlight shooting. at stop-down, the differences would be in the specular highlights.

as mentioned already, even at wide open the difference would be noticed, but not just for light transmission but bokeh rendering as well. a 1.2 has a unique bokeh that a 1.4 lens could not replicate no matter what. they are just completely different and more like comparing apples to oranges. this is not like a comparison between a 55/1.8 and 55/2 that are similar in optical design.

for lowlight or night shooting, the 1.2 would just trump the 1.4.

[urje]

@Blue: I agree these two shots are very different, but with different cameras and an 1.5 stops difference in exposure (assuming the same conditions, and that my late-night math doesn't fool me), I find it hard to compare these shots. Voe's examples on page 3 were much more convincing to me:

I would get the f/1.2 instead of f/1.4 first for the bokeh difference because of the shorter DoF and second for the better low light ability.


Zeiss Planar 50mm f/1.4 @ f/1.4




Pentax K 50mm f/1.2 @ f/1.2



For me it's better to "cry" once when I buy the Pentax f/1.2 but then smile every time I take a photo with it.

(i hope it's alright to hack broken imagelinks into a quoted message...)

[Pål Jensen]

this is basically the wrong impression that some people have with the 1.2. having handled both lenses, the difference is night and day in terms of practical and aesthetic performance..

No. He is right. I have owned both lenses and no one can say wether a shot is with one or the other wide open. That different lenses display different bokeh is nothing new and that is matter of taste.
BTW I haven't seen a single wide open image that wouldn't benefit from stopping the lens down!

[Blue]

No. He is right. I have owned both lenses and no one can say wether a shot is with one or the other wide open. That different lenses display different bokeh is nothing new and that is matter of taste.
BTW I haven't seen a single wide open image that wouldn't benefit from stopping the lens down!

You just side-stepped the light gathering ability just like he did. We aren't talking about just shooting at 5:30 pm in the summer but also at 9:30 pm. Furthermore, the A 1.2 can be used any other time as well so both of you have demonstrating why the 1.2 lenses are superior over all to the 1.4. Plus, some situations benefit from not being stopped down . . . that also goes to taste/preference.

[Blue]

@Blue: I agree these two shots are very different, but with different cameras and an 1.5 stops difference in exposure (assuming the same conditions, and that my late-night math doesn't fool me), I find it hard to compare these shots. Voe's examples on page 3 were much more convincing to me:



(i hope it's alright to hack broken imagelinks into a quoted message...)

I realize they were on different bodies. I had to punch up the ISO on the K20d to 1600 so the FA could hang with the A 1.2. That did result in a better shutter speed for the FA. I would have liked to have switched lenses around on the bodies but it was very dark where I was standing. and didn't want to risk dropping something.

Edit: We all know the K200d's sensor is inferior to the K20d sensor so it had to be the lens.

[Pentaxor]

No. He is right. I have owned both lenses and no one can say wether a shot is with one or the other wide open. That different lenses display different bokeh is nothing new and that is matter of taste.
BTW I haven't seen a single wide open image that wouldn't benefit from stopping the lens down!

not true. please refer to the post with images preceeding yours. 1.2 shows much shallow depth and is exposed brighter than the 1.4. this has nothing to do with taste or preference but rather lens capability. the difference is right there and for sure the images show how different they looked and can be easily identified. the subjective bokeh that you were referring also is an admission in itself that both lenses are in fact, different.

[Pentaxor]

You just side-stepped the light gathering ability just like he did. We aren't talking about just shooting at 5:30 pm in the summer but also at 9:30 pm. Furthermore, the A 1.2 can be used any other time as well so both of you have demonstrating why the 1.2 lenses are superior over all to the 1.4. Plus, some situations benefit from not being stopped down . . . that also goes to taste/preference.

if he says that there isn't really a difference, would he be willing to trade his A50/1.2 for an M50/1.4? just say the word and I would gladly send my M50/1.4 right away.

market price shouldn't be a discussion since they are practically, not different. right?

anyway, I'm not kidding about the trade. Pal, just send me a pm if you're serious.

[Digitalis]

"no one needs f/1.2"


...I wonder what this guy would think of my use of the Leica 50mm f/1.0 noctilux on the subject of the pentax 50mm f/1.2 Vs f/1.4 lenses, I can say that with my collection of over 160 50mm lenses it is my qualified opinion that f/1.2 lenses are indeed something special. And while their prices are high I cannot say they they are unjustified. You aren't just buying a slightly faster lens you are buying a lens that will bring you freedom to shoot in places where other photographers with their "fast" f/2.8 zoom lenses would have packed up and left. The differences don't end there either, most f/1.4 lenses don't perform as well as f/1.2 lenses typically do at f/2 and there are differences in the number of apeture blades, differences in handling of flare,coma,corner sharpness, micro contrast and lastly, bokeh rendering. All you need to do is take a look at the images photographers make with f/1.2 lenses in general and compare them against the images from f/1.4 lenses typically people who slap down the kind of money needed to buy an f/1.2 lens knows what they are doing.

[Pentaxor]

"no one needs f/1.2"

this notion is somehow contradictory due to the fact that he owned a 1.2. thus brings out the question of purpose of his ownership of such lens, much less so usage at f1.2. the assumption or generalization that people buy the 1.2 and never use it at wide open is nothing more than his own personal preference that he would insist that others do as well is rather a fallacy and is not even a fact at all. the existence of faster f-stops and images shot at such wide openings is a testament that such notion is false.

personal taste at shooting stop down or at smaller apertures has nothing to do with the lens capability. it's more like driving a ferrari at 50 miles per hour and say that a Honda SUV can run that fast as well.

[Blue]

"no one needs f/1.2"


...I wonder what this guy would think of my use of the Leica 50mm f/1.0 noctilux on the subject of the pentax 50mm f/1.2 Vs f/1.4 lenses, I can say that with my collection of over 160 50mm lenses it is my qualified opinion that f/1.2 lenses are indeed something special. And while their prices are high I cannot say they they are unjustified. You aren't just buying a slightly faster lens you are buying a lens that will bring you freedom to shoot in places where other photographers with their "fast" f/2.8 zoom lenses would have packed up and left. The differences don't end there either, most f/1.4 lenses don't perform as well as f/1.2 lenses typically do at f/2 and there are differences in the number of apeture blades, differences in handling of flare,coma,corner sharpness, micro contrast and lastly, bokeh rendering. All you need to do is take a look at the images photographers make with f/1.2 lenses in general and compare them against the images from f/1.4 lenses typically people who slap down the kind of money needed to buy an f/1.2 lens knows what they are doing.

You had to go and bring up the 1.0. However, why stop there? Bring out the 0.95! You may have to sell 80 of those 50s though.

[Kerrowdown]

For me, both the bright viewfinder and its low light capability makes it the best tool for the kind of work I do, that's why I bought it.

Go on treat yourself now and then.

[vizjerei]

I sold my FA50 1.4 and keep my K50 1.2, I guess I am the "no one" :P

half stop of light may not mean much, where you can say one can just pull it up with RAW. But you can't recreate the DOF. By getting a 1.2 lens you just give yourself a extra range of choice in aperture to use. Can you live without it? sure. Is it nice to have? Of course! Does it worth the $, to me yes. It is just another creavtive tool, just like someone asking 12mm lens and 14mm lens.

[Blue]

I sold my FA50 1.4 and keep my K50 1.2, I guess I am the "no one" :P

half stop of light may not mean much, where you can say one can just pull it up with RAW. But you can't recreate the DOF. By getting a 1.2 lens you just give yourself a extra range of choice in aperture to use. Can you live without it? sure. Is it nice to have? Of course! Does it worth the $, to me yes. It is just another creavtive tool, just like someone asking 12mm lens and 14mm lens.

People have a tendency to overlook the fact that a half of a stop is more at the larger apertures than them smaller ones. In other words its not linear.

[Pentaxor]

yes, it's true with UW lenses as well. 2mm difference means a lot in the wide range as opposed to the 20mm differences in the longer end.