The SMC Pentax 50mm F1.2 is the original version of Pentax's fastest SLR lens. It was later replaced by an A counterpart. A special gold-plated version was briefly made together with the Gold LX.
I can recommend the SMC Pentax 50mm F1.2: Yes |
Price (U.S. Dollars): $400.00
| Rating: 8
Pros:
Fast , Creative DOF, Sharpness, Build quality
Cons:
Hard to manual focus (inherent to aperture), Non-A lens
This one is all about the 1.2. I have the FA 1.4 and the M 1.7 also, and you would be hard pressed to find significant differences between them from f/2 upwards. What this one brings to the table (aside from the obvious light-guzzling ability) is decent sharpness at 1.2 and 1.4, and the creative aspect of the shallow DOF and strong bokeh in situations where you wouldn't normally expect it. All in all, it offers composition choices that just aren't available in any other way. And MASSIVE bragging rights
One thing that surprised me was that (to me at least) it seems that, although the resolution is close to superb, contrast and saturation are rather muted - of course, in our digital raw post-processing age, this could count more as a strong point, giving the shooter more leeway.
I can recommend the SMC Pentax 50mm F1.2: Yes |
Price (U.S. Dollars): $375.00
| Rating: 8
Pros:
Fast, Low Light Ability, Extreme Shallow DOF
Cons:
Manual Focus,
The build quality of this lens is incredible (easily 2-3 times the weight of a kit 18-55mm lens). The lens is fast. It can capture subjests in low light situations with little trouble. I was surprised to see that it was quite sharp wide open. The real treat with this lens is the extreme shallow depth of field that it can bring to the table. The bokeh is like no other. You can sit at a table snap a picture of a friend and reduce everything but your subject into a pleasant out of focus bokeh blur. Great for shooting in clutered or tight areas where you need to obsure the background. The other feature with this lens is that you can stop it down and get good depth of field which makes it a real double edged sword. And like the review before me stated, the lens comes with bragging rights.
I can recommend the SMC Pentax 50mm F1.2: Yes |
Price (U.S. Dollars): $300.00
| Rating: 8
Pros:
it is f1.2, it is unique, creative DOF and bokeh
Cons:
manual focus
It is old, it is heavy, difficult to focus because narrow DOF.
It creates beautiful bokeh, more smoothly than that from FA50/1.4 even with bigger apperture.
It is full metal with quality of typical K series lens.
No "A" setting means no EXIF data. No better than other 50mm's when stopped down.
Softness Controversy: Contrary to reputation, this lens isn't really soft wide-open. It is quite usably sharp. Three factors contribute to the "softness" reputation:
1. The depth of field when used on an APC camera at f1.2 and about 6' distance is roughly 3". (For those nice flower pictures others have posted, the distance is about 3' and dof is about 1/2"). Given that almost any 3-D object you photograph will be bigger and deeper than a couple of inches (that includes a person's face), some portion of the picture will always be "soft".
2. There is a certain type of spherical aberation that shows up as a "coma" around pictures taken at f1.2 (it only shows under certain lighting conditions), but it contributes to the "softness" factor.
3. Contrast is lower at f1.2, so it appears less sharp. (This is true even if using the FA1.4 wide open).
Those three points aside, if you take a picture wide open against a flat object using a tripod, I think you'll be surprised at the wide-open sharpness of this lens. I have a large collection of autofocus and manual 50mm lenses, F, FA, DFA, A, M in 1.4, 1.7, 2.0, 2.8, flavors and the 1.2 will hold its own against any of them. (Stopped down, they all perform very similarly)
The Bad: The reality of it is at f1.2, if you do the mathematical calculations for f stops (in terms of how much light area being let in), it really is only 1/3 stop faster than an f1.4 lens. In fact, in actual usage, I discern little to no difference in speed difference between this lens and my FA1.4. Disappointing, but true. (Update 2/10/09: I have upgraded to a K20 and strangely enough, I can now see a clear difference in brightness of the pictures between my FA@1.4 and K@1.2 )
The Good: If this lens is no faster (in practice) than a 1.4, why am I recommending it? This lens is a joy to use. It is more than just the smooth focusing, the feel of the metal and the low light ability (which I have in almost all K and M series lenses). The relatively rarity of this lens, the reputation, the nice bokeh, the shallow DOF, and even the weight lends a certain excitement and challenge to using this lens which just makes it so much more fun than just "taking a snapshot" using an autofocus lens. (Or perhaps it is just the price, 4x that of a M f1.4 lens, which is very nearly as nice in most regards.)
Useful Tip (No Stop Down Metering Necessary!): Most people probably never bother using M and K series lenses under the camera's AV mode. This is because Av mode can only be used wide open for lenses that don't provide "A" functionality. However, in the case of THIS lens, the Av mode is invaluable because why else did you want a f1.2 lens? To use it WIDE OPEN of course. So in essence, the most useful f-stop setting (f1.2) is available for use in Av mode on this lens. (It still won't work with the flash, but then again, you didn't get a f1.2 lens to use with a flash did you?) So no more green button!
Update 2/10/09: I recently found out from some other forum members that you can apply a piece of scotch tape to the area on the lens where the camera contacts are to prevent them from shorting. The result is you can now use all "K" and "M" lenses in Av mode for the first 3 stops by adjusting the aperature ring and compensating by setting the Exposure compensation by the same amount. This allows much more accurate metering and faster usage than the "Green" button stop down method. It works really well and does not damage the lens in any way!
When you decide to get your own 50mm f1.2 lens, don't fool yourself. For quick and efficient work, this lens is no match for a FA1.4. The purpose of this lens is for thoughtful composition, use of creative DOF, interesting bokeh, and possibly most important, to have a unique piece of Pentax history. If you're going to stop it down all the time, why bother? Any of the other 50's will do and probably be much cheaper.
Oh yeah, and I recommend getting a hood due to the extremely large and exposed front element causing flare and reduced contrast.
I can recommend the SMC Pentax 50mm F1.2: Yes |
Price (U.S. Dollars): $266.00
| Rating: 10
Pros:
Speed, quality, sharpness & bokeh.
Cons:
Perfection comes at a price!
To be honest when I bought this lens about a year ago, I wasn’t overly impressed. I already had the K50/1.4 & K55/1.8, which I both liked and I mostly bought the K50/1.2 to complete the set of K series standards released in 1975. The K50/1.2 is the biggest of the three standards and even for a K series lens seemed rather large and heavy, more like a telephoto. (Of course the size and weight is due to the optics required to produce an f1.2 lens, notice there is no “M” version of this lens.)
I travel a lot and seemed to always take the smaller K50/1.4 or K55/1.8, so the
K50/1.2 did not get a lot of use. A few months back I started to really use this lens around town and have completely changed my opinion. This is a totally different lens than the other K series standards and is more of a creative specialty tool.
Reasons:
- The fast f1.2 makes for an incredible bright view finder even when shooting at night.
- Amazing 3D images that you can create when you play around with the DOF.
- The incredible bokeh, with or with out using a ND filter.
- Sharper than the K50/1.4 and equal or better than the K55/1.8.
I also do not think it is fare to dock points when reviewing this lens, because it’s a manual focus or does not do this or that on a DLSR. Would you criticize a 35 year old Ferrari because it does not have an AUX jack for a MP3 player? My review is based solely on using this lens on a KX & K2 film camera.
The K50/1.2 was a revelation when it was released in 1975, “The Worlds First 50/1.2 Lens” and almost 35 years later it is still (along with the "A" version) the fastest Pentax lens ever produced. This lens belongs in the optical hall of fame and giving it a rating less than 10 is an insult to Pentax. Yes it’s that good.
PS: Make sure you get either the square or round dedicated Pentax lens hood, which fits the other K series standards. (52mm filter size)
I can recommend the SMC Pentax 50mm F1.2: Yes |
Price (U.S. Dollars): $290.00
| Rating: 9
Pros:
great build, smooth focus, sucks in light
Cons:
tricky to use wide open, needs appropriate hood, heavy
I will not go into details here because I have a thread with real-world examples of the sorts of shots you can get with this lens wide open and stopped down. For the modest amount this cost, this lens is a great deal, fully usable at f/2 and very nice at f/1.2 if you take care. It is a bargain compared with the more convenient A version.
I can recommend the SMC Pentax 50mm F1.2: Yes |
Price (U.S. Dollars): $385.00
| Rating: 9
Pros:
speed, IQ, build quality
Cons:
weight (for 50mm)
This is one great lens to own.
It's built like a tank, and it weights just about as much too. But then you would expect it from f1.2 lens with fully metal build.
It's bit bigger than other 50s and roughly 2x the weight. But that's just about as much of a negative I can find on it.
The IQ is simply great. Lens is perfectly usable even at f1.2. The problem here is that the DOF is minimal at this setting so it does need to be properly focused, and split screen comes handy. I would not try to use it at f1.2 without split screen!
Stopping down to f2 IQ gets just fantastic and holds it's own until f11 easily.
Colours and contrast are great and OOF rendering is superb (smoother at any f stop than OOF areas of DA*55, FA43 and K55/1.8).
Focusing ring is smooth (though not as smooth as my K55/1.8) and turns around 250 degrees, so MF is delight.
All in all, if you don't mind lugging some heft around, this is great lens to own.
edit: after some 7 weeks of use, I have to say that optically this is perhaps the best lens I have used (and those include 31&43ltd, DA*55, K55/1.8)
I can recommend the SMC Pentax 50mm F1.2: Yes |
Price (U.S. Dollars): $310.00
| Rating: 8
Pros:
The DOF, build quality, sharpness, viewfinder brightness.
Cons:
Small lack in contrast at 1.2, flare
For the record, I only shoot film.
A real joy to use, smooth focussing and solid feel. The viewfinder is also very bright and the shallow DOF makes it very easy to hit focus, however it also makes it a little bit of a hassle to get it precise if you shoot at 1.2.
Bokeh? Yes! a lot of it, and very nice in my opinion. It is smooth and creamy most of the time. Extreme highlights on the other hand produce shapes according to the aperture, depending on the situation it can be both good and bad. I see it as a positive as you can use it creatively and it is fairly easy to control.
At 1.2 it is already usably sharp but a little lacking in contrast, not very noticeable if you're not comparing the same scene wide open and stopped down.
The lens is quite prone to flare in some situations, a hood helps but does not resolve the problem if there are strong highlights in the picture. I guess this is what you can expect with that huge front lens element.
In all a very nice lens, but it does not stand up for the price or performance if you don't use the wide open possibilities from time to time.
As I see it, this lens does everything that a 50/1.4 does, with the addition of the possibilities that 1.2 brings. Also I'm not sure which is better, a good 1.4 wide open or this lens stopped down to 1.4. I'm planning to do some tests and will come back with results. If it outperforms my K50/1.4 in that comparison I will have to give it a 9, but for now it is a strong 8.
I can recommend the SMC Pentax 50mm F1.2: Yes |
Price (U.S. Dollars): $267.00
| Rating: 10
Pros:
WOW-Fast, unique bokeh, build quality, DOF, focus ring
Cons:
Unique bokeh not for everyone, tough to focus without split-prism
This lens spends more time on my K10 than it's kit lens does. I could not afford much in the way of lenses as I am not pro (I do shoot weddings on occasion though); I decided to go with one nice prime in the stead of a 'good' fast fixed FL zoom (I have not seen a "great" *and* fast fixed zoom in the useful range of ~16-50mm or so).
This lens is FAST and built like a Brick $#!+house :-) Seriously, it is tank yet very compact due to it's manual nature.
The bokeh has been described to me as:
harsh; rough; interesting; nice; unique; different...but never as soft, warm, and fuzzy. :-) I like it, I try to use the "interestingness" of the bokeh in my shots.
Images crisp up very nicely when stopped down to 2.8 or so.
The DOF at 1.2-2.0 is SO SHORT that it can actually make you laugh or cuss...depending on the need of the moment.
The think I dislike most about this lens? I need to point out that "it" is part and parcel to the beauty of the lens...so it is tough to say I "dislike" it... it is more appropriate to say that while acclimated I still find it frustrating sometimes: Focusing the 50-f1.2 on a dSLR with the stock screen is anywhere from fun to FRUSTRATING :-) If you are an amateur accustomed to AF...you will have an opportunity to discover the "FUL" range of words (like Wonder... and Awe...): Once you are acclimatized though...you will love it too.
I would love to have a hybrid screen that has the focus points AND the split...
I will not sell this lens anytime soon.
It will reward the user with brilliant results when given the right target and parameters.
It is great in a low-light pinch (if you can live with the DOF at such a fast F-stop).
(Update 2/10/09: I have upgraded to a K20 and strangely enough, I can now see a clear difference in brightness of the pictures between my FA@1.4 and K@1.2 
)
