This was one of my favorite lenses while I used my Olympus E3. The images were tack sharp right from the get go..... wish the Canon 50L or the Nikon 50mm f1.4 AF-S were this good.
Agree on most of what the review states - except, the vignetting and other issues he mentions were not as bad in real life shooting. This lens was definitely worth the $$$'s.
The Canon/Nikon are actually just as good , or even better - you're just comparing them wrong...
To compare with anything resembling fairness you have to multiply aperture too. 50F/2.8 will result in the same picture (with an FX-camera) as the 25 on 4/3, wide open at F/1.4. Same view angle, same DoF, and exactly the same amount of light will hit the sensor if you use the same shutterspeed.
Compare THOSE results, and you will find that the very much cheaper (half-price!) FX alternatives are quite a lot sharper at corresponding apertures, especially in the corners. 50F/1.4 isn't mirrored by the "25F/1.4" on the 4/3-format, the corresponding lens would be a "25F/0.7".
Total amount of light would be the same but lihgt intensity i.e. light per unit area would be higher in the m4/3 case and thats what determines the exposure not the total amount of light. So I am afraid your analysis is not correct
theSuede wrote:
The Canon/Nikon are actually just as good , or even better - you're just comparing them wrong...
To compare with anything resembling fairness you have to multiply aperture too. 50F/2.8 will result in the same picture (with an FX-camera) as the 25 on 4/3, wide open at F/1.4. Same view angle, same DoF, and exactly the same amount of light will hit the sensor if you use the same shutterspeed.
Compare THOSE results, and you will find that the very much cheaper (half-price!) FX alternatives are quite a lot sharper at corresponding apertures, especially in the corners. 50F/1.4 isn't mirrored by the "25F/1.4" on the 4/3-format, the corresponding lens would be a "25F/0.7"....Show more →
rhameed wrote:
Total amount of light would be the same but lihgt intensity i.e. light per unit area would be higher in the m4/3 case and thats what determines the exposure not the total amount of light. So I am afraid your analysis is not correct.
He just forgot to mention that you'll have to use two stops higher ISO, which since the sensor is four times larger, is equivalent in terms of amplification of the signal. That means that you'll get approximately the same noise.
"Exposure" as in light effect per unit area is really quite useless as a comparing metric. If you want to use that definition I suggest you try your average cameraphone or compact camera at ISO6400. If that definition is right and just for comparisons, then that should be the same as the D700 on ISO6400. Take a guess.... It isn't. Total amount of light is what matters.
Of course a good F/1.4 lens is always impressive, and I've seen few other large aperture lenses be as sharp all the way from wide open. As for "haven't used it..." bla bla bla - have YOU ever tried comparing pictures from FX 50/2.8 and 4/3 25F/1.4 taken from the same viewpoint? The results ARE virtually identical, if you disregard the "personalities" of the individual pieces of equipment...
theSuede wrote:
The Canon/Nikon are actually just as good , or even better - you're just comparing them wrong...
To compare with anything resembling fairness you have to multiply aperture too. 50F/2.8 will result in the same picture (with an FX-camera) as the 25 on 4/3, wide open at F/1.4. Same view angle, same DoF, and exactly the same amount of light will hit the sensor if you use the same shutterspeed.
Compare THOSE results, and you will find that the very much cheaper (half-price!) FX alternatives are quite a lot sharper at corresponding apertures, especially in the corners. 50F/1.4 isn't mirrored by the "25F/1.4" on the 4/3-format, the corresponding lens would be a "25F/0.7"....Show more →
That's a false equivalence since exposure is based on light density not total illumination. Total illumination is utterly irrelevant to photography.
You get the same exposure as a 50mm f1.4 at f1.4 with a 25mm f1.4 at f1.4. You get the DoF of a 50mm f2.8 however. This can be an advantage or a disadvantage depending on what you are looking for. If shallow DoF effects are not required the 25mm f1.4 with it's significantly increased DoF at a given aperture over the 50mm f1.4 at the same aperture can actually be an advantage in wide aperture shooting.
theSuede wrote:
"Exposure" as in light effect per unit area is really quite useless as a comparing metric. If you want to use that definition I suggest you try your average cameraphone or compact camera at ISO6400. If that definition is right and just for comparisons, then that should be the same as the D700 on ISO6400. Take a guess.... It isn't. Total amount of light is what matters.
Actually, that is once again a false comparison. What matters for sensor performance is pixel pitch (given otherwise equivalent sensors, ie fill factor, microlens coverage, etc). A phonecamera with the same pixel pitch as a D700's sensor can deliver the same noise performance as the D700 can, albeit at a very low resolution. A D700 with the same pixel pitch as a cameraphone would have the same awful noise performance, albeit at a fairly ridiculous resolution. The advantage to larger sensors is in pixel pitch increases at a given MP count, not the increase in total illumination. The secondary controlling factor is heat (big sensors take more juice and thus run hotter, one reason why MFDB's have worse noise at ISO's other than base, they run hotter than FX sensors)
Of course a good F/1.4 lens is always impressive, and I've seen few other large aperture lenses be as sharp all the way from wide open. As for "haven't used it..." bla bla bla - have YOU ever tried comparing pictures from FX 50/2.8 and 4/3 25F/1.4 taken from the same viewpoint? The results ARE virtually identical, if you disregard the "personalities" of the individual pieces of equipment...
That depends seriously on the subject, since the FX 50/2.8 exposure would either be at 2 stops higher ISO or 2 stops lower shutter speed or some mix of the two. A 4/3rds 12MP shot at f1.4, 1/125 and ISO 800 on say an E-30 would be less noisy than that FX 50/2.8 at f2.8, 1/125 and ISO3200 on say a D700 (Cameras picked to normalize MP count, ISO's picked specifically to invalidate your comparison as ISO 3200 is where visible noise starts to occur on the D700 while ISO 800 is the highest ISO without visible noise on an E-30). Also if you're shooting at the same ISO you run into issues like motion blur on the 50/2.8 shot.
Total illumination is directly translated into total frame signal-noise ratio. DoF is always gained at the loss of total illumination. More DoF - more noise.
As I said - if that's your standpoint I expect that you use your compact camera at ISO6400 and that you find the results totally acceptable. Not very likely.
Jonas B wrote:
(...)
On another aspect I also wonder how many posts about the lens there will be by people not having used it?
theSuede wrote:
As for "haven't used it..." bla bla bla - have YOU ever tried comparing pictures from FX 50/2.8 and 4/3 25F/1.4 taken from the same viewpoint? The results ARE virtually identical, if you disregard the "personalities" of the individual pieces of equipment...
Hallå svensken,
As you can see my comment on people posting about the lens was "On another aspect" - rest assured I know about equivalence. If you want to comment feel free to do so but don't drag my words out of context.
On your question I can reply with a Yes. I have even posted the results here, in a thread about DOF, aperture openings and focal lengths.
theSuede wrote:
Total illumination is directly translated into total frame signal-noise ratio. DoF is always gained at the loss of total illumination. More DoF - more noise.
As I said - if that's your standpoint I expect that you use your compact camera at ISO6400 and that you find the results totally acceptable. Not very likely.
Total illumination is NOT directly translated into total frame signal-noise ratio. At best it's a secondary factor due to the fact that higher pixel counts can mask increased per-pixel noise in a sensor of a given size. The controlling factor in per-pixel noise is total sensor site illumination, which is primarily a factor of sensor site area (ie pixel pitch), the major secondary factor is total MP, which controls the magnification of the final result at a given print/display size (and magnification of the individual pixels in the final output is THE major controlling factor in how visible a given amount of noise is). Total illumination matters only in that you get more of it if you use large sensor sites at a high pixel count. It's not a primary factor.
The breakdown on exactly which the tradeoffs go is specific to the individual designs involved. For example there isn't a 2 stop advantage in noise performance between a D700 and an E-30 until you hit ISO 1250 on the latter. There would be if total illumination was the primary factor rather than a secondary one that can safely be ignored since it's not an accurate predictor of noise performance (Compare a D3x and a D700 at ISO 3200 sometime, if total illumination was the controlling factor their noise performance would be near-identical. It's not, even after normalizing display sizes).
Give me a compact camera with 8.4 micron pixels from a current-generation sensor and current generation processing and I'll give you a low-noise ISO 6400 image. Stick me with a classic high pixel density P&S sensor and the image is going to suck.
Could you link that thread, Jonas? I'm certain you made a good comparison out of it :-) Thank you. My "bla bla bla" was primarily meant for people that have gone blind into religious beliefs centered on their own system without actually comparing. I'm certain that the 25F/1.4 is an impressive lens, on the 4/3-format. I haven't tried it, but I'm hugely impressed with the Oly 50F/2 and the 150F/2.
Maws - we're not talking about the same thing - and you're taking the word "picture" totally out of its context. My "boundaries" for the equivalence test with "same picture" are:
*same total picture resolution (how can it be "the same picture" otherwise?)
*same shutterspeed - which together with:
*same DoF - remember that the pictures are "same resolution", so this is easy
*same "FoV" - gives the same amount of light onto both sensors if the two criteria above are satisfied.
If I give you a compact with 8.4�m pp, it will have a resolution of ~800x600 - and that picture will hardly be comparable with the E-30 or the D700, seen as a total picture's worth. But at F/2.8 and a certain shutterspeed, it will indeed have the same noise per pixel as the D700, only 25 times less pixels... For me that's 25 times less picture (or a 5 times smaller picture - when measured linearly).
But if you think 800x600 is equivalent to a D700's 12MP - please go ahead and reduce all of your picture libraries to that resolution - it will save you MASSIVE amounts of space.
[edit] and I forgot - pictures taken from raw's at www.imagingresource.com. Their general policy is that noncommercial use of their pictures is ok for educational purposes, as long as you link them. I forgot that earlier, rude of me...
[end edit]
Colour corrected to look the same, with curves on linear gamma colour space. Same raw-conversion settings, same everything. One is D700@ISO1600, the other is Oly520@400.
D700: 1/160 F/8
520: 1/125 F/5 (which is virtually the same as 1/160 F/4, but F/5 chosen for better sharpness)
Unfortunately you can't see the DoF in this picture, but it would with a very high certainty be a little bit deeper on the Oly. This depends on the optics, to a small degree.
Makten wrote:
Yeah, that's why medium format cameras are only used by fools. Every professional photographer knows that a cellphone camera is just as good.
Ehm...
Total Illumination is irrelevant to why medium format cameras are used. They're used for the high resolution, the smooth tonality which high-resolution film or digital gives and the shallow DoF effects which you can achieve.
Smooth tonality comes from low photon shot noise per picture element (pixel) combined with high resolution. Low shot noise = lots of light. Light amount is equal to the space angle of the view times the area of the aperture. Same aperture, larger space angle of view = more light. More light and same resolution = less noise.
The high resolution would be a total waste, if the light amount over the frame was the same as on a 36x24 sensor. It would all be noise - the equivalent of using a VERY very high ISO.
