E-M5 vs. E-P3: JPEG Image Quality

Below I have combined test charts shot with E-M5 and E-P3 at various ISO settings. Settings while shooting:

• Lens Zuiko D. 50mm f/2 Macro @ F4
• JPG Large Fine (I saved also RAW files to be compared later) (note: there is no visual difference between files saved at Large Fine or Large Super Fine jpeg compressions at 100%, unless you start to do heavy post processing)
• Picture Mode: 4 Muted @ Contrast -2, Saturation -2, Sharpness -2, Gradation Normal (note: normal means Olympus standard jpeg gamma curve)
• Noise reduction & noise filter: OFF
• Equal aperture and shutter speed settings in both bodies at corresponding ISOs

JPG files were opened in Photoshop, normalized and cropped equally. E-M5 crops are 100%. E-P3 crops were enlarged to same size through Bicubic Smoother interpolation. All images are slightly sharpened. No noise reduction applied. (All test shots have gone through automatic normalization which sets certain amount of lowest values of lowest channel to zero. In E-P3 shots you can see more black outline between white and black than in E-M5 shots. Anything stronger than what I did would lead into losing detail in shadows. I left corrections as they are, and that´s why some E-P3 scales look lighter than the same ones with E-M5. You can copy test charts and tweak them if you want to have another "look".)

I chose to enlarge E-P3 files because I am interested in seeing quality in same size prints. This is closest to that situation on screen. Just remember: To see any real difference in sharpness at ISO 200 to 400 you need to print larger than A3. 

E-M5 is markedly better in every regard: sharpness, signal to noise ratio, dynamic range... . At higher ISOs E-M5 gains about two stop improvement. This result comes from new sensor with more resolution and better pixel per pixel quality, thinner low pass filter and impoved JPG processing.

I will post later more images and compare RAW files.

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Image below E-M5, M.Zuiko 12mm f/2 

• ISO 200, @F6.3
• JPG Large Fine
• Picture Mode: 4 Muted @ Contrast -2, Saturation -2, Sharpness -2, Gradation Normal
• Noise reduction & noise filter: OFF
• Crops 100% from brightest and darkest area without any modifications

Image below E-M5, M.Zuiko 45mm f/1.8

• ISO 1600, @F2.5
• JPG Large Fine
• Picture Mode: 4 Muted @ Contrast -2, Saturation -2, Sharpness -2, Gradation Normal
• Noise reduction & noise filter: OFF
• Normalization and slight sharpening in Lightroom 3
• Crop 100%, no noise reduction applied

Olympus E-M5: Dynamic Range

I shot a test series with E-M5 and E-P3 to determine their relative dynamic or tonal ranges at various ISOs. Table below shows my findings.

These values are calculated from images opened in Olympus Viewer 2. This software opens RAW images but it actually emulates in-camera JPEG process. I used here lowest contrast and normal curve.

Dynamic range is not defined unambiguously. Here I used certain contrast edges to decide where detail ends and noise starts. E-P3 curve shows two anomalies: at ISO 800 and ISO 12800, they come from the fact that I shot at 1/3 EV intervals and at those points shadow and highlight exposures happened to have more distance. DxO Mark gives a dynamic range of 10.1 EV for E-P3. It is measured directly from sensor. Here we have more variables and maybe we should use rather the term tonal range. These EV values should not be taken too seriously as absolute ones, they are simply a result of certain process.

The important result is: E-M5 has markedly better dynamic range, in image files it is around 2 EVs. I´m having a bit difficult time looking at this graph, but this is what I see in highlights and shadows. So much wider range of details can be found in E-M5 files in Viewer 2 software. ISO values in table are nominal. E-P3 ISO values are actually lower than nominal, E-M5 sensitivities are closer to nominal values.

Addendum: Conclusion

After a well slept night I thought that I need to write a few more lines because the above result is, well, remarkable. I have seen news about an interview where Olympus spokesman said that there is a 30% improvement in DR. What does 30% mean? Is it 30% of doubling DR which is 0.3 EV? Is it 30% more above 10 EV, which is 3 EV? Anyway: If you shoot JPGs or use Olympus Viewer 2, my test tells that you get a lot more. You can get more details to work with for some 0.3 steps in highights and 1.7 steps in shadows when compared to similar settings and exposure and in E-P3. This result may or may not be true with third party RAW processors. I will come back to it later.

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Olympus M.Zuiko 12-50mm f/3.5-6.3 in comparison

During this time of year we have not much light even during daytime and the weather in Southern Finland has been quite cloudy and rainy. Because of that I decided to do a traditional test target shoot to compare the new zoom with some of my other lenses. 

Above is my test setup. I used two targets, one in the center and the other in the right upper corner. I shot the same "subject" (marked here as grey area) with different focal lengths. Of course distance varied accordingly to keep (subject) area the same. I used studio flashes and used their power settings to keep exposure on sensor constant in every picture. Accuracy was 1/10 stop. This way the differencies in lens diaphragm did not affect the results. I also focused center and corner targets separately to compensate for possible curvatures in lenses´focal planes. All test pictures were shot at ISO 200. Camera was Olympus E-P3. RAW images were opened in Lightroom 3.6 and I did a basic normalization of tones, correction of chromatic aberration and added sharpening. Those are the same basic tweaks I would do to real pictures. Possible distortions were not corrected as can be seen in corner shots.

Focal Length 12mm

The first comparison shows the center of 12-50mm zoom at full aperture F3.5 and closed at F5.6. Focal length is widest, 12mm. These are 100% crops, like all other target images here. The image quality gets better with smaller aperture as would be expected here.

 

Olympus´4/3 series zoom lens Zuiko D. 12-60mm f/2.8-4.0 is the perfect comparison lens for any lens having the same focal length range. Here we can see center targets. This result is in line with Olympus´MTF curves below: 12-60mm zoom is a great lens, and especially its resolution (orange curves) is higher than with the new zoom. You can find more of these MTF curves at Olympus web sites. They are good tools when comparing lenses.

 

In upper line of this picture we have the corners of 12-50mm zoom at apertures F3.5 and F5.6. Contrast and resolution gets better with smaller aperture, but radial (sagittal) and tangential (meridional) lines have a very different resolution. It can be also seen in MTF curves, where continuous line is sagittal and dashed line is meridional transfer function. For comparison we have corner shots with 12-60mm zoom at F3.5 and and M.Zuiko 12mm f/2 prime at F4.0. 12mm lens is not too good in corners, but it has this reasonable level all ready from F2.

Focal Length 14mm

 

As a further comparison lens we have M.Zuiko 14-42mm f/3.5-5.6 II kit zoom. Above its results at 14mm focal lenght and apertures F3.5 and F5.6. Left side images are from center and right side images are from corner. Now 12mm and 14mm focal lengths are so different that they should not be compared directly. That´s why I have below a common focal length of about 19mm.

Focal Length about 19mm

 

Here I set the shooting distance with Lumix G 20mm f/1.7 prime. After shooting with it, I shot with those three zooms from the same spot while setting zoom or focal length so that the cropping was always equal. Zoom rings did not show 20mm because Lumix actually has not a 20mm focal length. It is maybe close to 18,5mm. These crops are from center. Lumix 20mm and Olympus 12-60mm zoom show almost identical performance. Wide open 12-50mm zoom has a good resolution but its contrast is not up to 14-42mm zoom.

 

Looking at corners, 12-50mm zoom has again nice resolution but contrast performance is very modest. Thus it is practically a draw with kit zoom. Maybe it comes as a surprise for some people but Lumix 20mm is not much better in the corners. Number one from these lenses is quite obvious.

Closing down to F5.6 makes Lumix 20mm markedly better in the corners than these zooms.

Focal Length 42mm

 

This comparison has on the left centers at full aperture and on the right corners, again at full aperture. 12-50mm zoom gets better all the time as focal length grows. 14-42mm zoom on the other hand sees especially contrast dropping at its longest focal length.

Focal Length 50mm

 

Uppermost, on the left, we have 12-50mm zoom´s center at full aperture. All the other crops are from the corner. 12-50mm zoom shows just slightly better contrast in corners when closed to F8. Still contrast performance is lower than resolution. As new lenses I included M.Zuiko 45mm f/1.8 at the same aperture F4 as earlier were Lumix 20mm and M.Zuiko 12mm. 50mm is 4/3 series Zuiko D. 50mm f/2 Macro. 

Macro setting

 

As close up test I did a watch image. At macro setting 12-50mm has a 43mm focal length. It can not be changed as zoom ring does not move when macro setting is engaged. Largest aperture is F6.0. Here we have the closest focusing distance of 200mm.

I tried apertures F8 and F11. The smaller aperture shows already effects of diffractions but on he other hand the better depth of field can be a bigger benefit. How ever, the 12-50mm lens is capable of very nice images with close up subjects. This is a 100% crop.

For comparison once more on the left the new 12-50mm zoom and on the right Zuiko D. 50mm f/2 Macro. Aperture is F8. Focusing differs between these images, please look for the sharpest details in both images. 

Conclusion

Zuiko D. 12-60mm f/2.8-4 is one heck of a lens. I guess that´s old news. The images should tell quite clearly the differencies. However, we must remember that this kind of very precisely made test target comparison is a lot harsher than any normal shooting. The differencies in normal shooting would not be in the same league, there are too many disturbing factors. Even slight differencies in exposure, focus or camera shake could obscure a lot. But, yes this is what you get when everything is optimized.

M. Zuiko 12-50mm f/3.5-6.3 is a very reasonable lens for photography with its longer focal length and especially for close up shooting. Otherwise it fits better for video because of its silent and fast focusing and silent power-zoom. For video it has plenty of quality. You can check this by scaling test shots into 50%. Then they correspond to Full HD quality. 

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Olympus E-P3 RAW Image Quality

 I shoot almost only RAW-files. As a converter I use mainly Lightroom 3. It can´t yet open E-P3 RAW-files. Olympus gave me the new version of their Viewer 2 software so that I can try how E-P3´s RAW files look like.  

Above there are three comparison images. They all are shot as RAW files at ISO 1600. The first image from up is shot with E-P3. It was converted into a TIF file in Olympus Viewer 2 software (new version updated for E-P3). Settings: Noise reduction off, sharpening -2, others default. The second (middle) image is shot with E-P2. Same exposure and same conversion in Olympus Viewer 2. Both images have the same sharpening and slight noise reduction to compensate in Lightroom 3.

My conclusions (from these and other images): Images from these cameras are close to each other with E-P3 having better resolution and sharpness. Noise is equal or slightly lower in E-P3. E-P3 images show better surface texture in objects. That would suggest that filters in front of sensor are of a better quality in E-P3. (Note: a really high quality low pass filter can be alone more expensive than E-P3). It looks like the basic sensor in E-P3 might similar to the one in E-P2 but all ”optical” parts and electronics in sensor unit are new.

In casual everyday shooting of RAW images, which are converted in Viewer 2 as above, you might not notice difference between images from these two cameras. There are too many variables. In a comparison the difference is there and the look of E-P3 images is sharper when you use high quality lenses. In my previous post I noticed that E-P3 can be a noticeably better camera for in camera processed and sharpened JPG´s, although E-P3´s JPG look doesn´t feel always right for me, who prefers graininess for too much smoothness.

The last image is the same E-P2 RAW file converted in Lightroom 3 to the same visual sharpness. As you can see converters are not equal even when striving equality, even without colors and large object dynamic range. Lightroom is both better and worse than Viewer 2. But as said there is a need for sharpening and slight nose reduction to compensate after Viewer 2 to get images that I like. Also colors depend totally of konverter settings. In RAW-shooting exposure of file, choice and use of converter and user himself is always the biggest factor. 

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E-P3 RAW, ISO 200. RAW conversion in Viewer 2. No problem with dynamic range in backlight. Nice detail from highlights to shadows. Good color.

Olympus E-P3 JPG Image Quality

Compared to E-P2 new E-P3 has also a new sensor and new image processor. According to Olympus image quality has improved by one stop.

Above: E-P2, ISO 800, Camera JPG Standard, NR Normal, Extra sharpening in LR3. Below: E-P3, same settings, No extra sharpening. (100% crop, Zuiko D. 50mm 1:2 Macro @ F4.0).

I shot a series of JPG test images with both camera´s ”even” ISO settings. At base sensitivity there is naturally no difference in resolution. When sensitivity goes up, E-P3 becomes gradually better so that at ISO 1600 it corresponds to E-P2 ISO 800 or is slightly better. Actually E-P2 image had to be helped with an extra sharpening to bring it closer to E-P3. Noise or graininess is stronger in dark grays in E-P3 image. From this point of view Olympus claim is true.

As can be seen in these frames  E-P3 image shows a watercolor-like smearing where structure or definition runs out. E-P2 has graininess in those areas. This difference in character is evident through out all ISO settings. Depending on subject smearing may not be seen at all at low settings and E-P3´s images can be very brilliant. Obviously it is sort of brilliance, that´s the best description I know, that Olympus seems to be after here. At higher ISO settings smearing can become disturbing if also reds spread and shadows have blotchiness.

Anyway, personally I do not like this kind of way to render as I already mentioned while writing about M.Zuiko 12mm images. I think also that this effect removes E-P3´s superiority starting from ISO 3200. I hope Olympus will  change rendering to be more like before. Now Olympus has been too much after clean, smooth and sharp look. A prompt firmware update, please!

My result and opinions here are strictly true only for camera JPGs at default settings. You can tweak the settings but still the same trend stays. Resuts could have been very different for E-P3 if I had swithced NR off and sharpening to minimum and tweaked those in post processing. But doing so would only make JPG shooting pointless. JPG´s whole idea is to produce as ready images as possible.

There was no RAW converter profiled for E-P3 and that prevents us from going any closer to the real capabilities of E-P3 sensor. Below, as an example, the same E-P2 exposure as camera JPG and converted from RAW in Lightroom 3. It is possible to squeeze out even some more resolution with Lightroom. And then you can get more out of tonality, dynamic range and colors, which I have left out of this blog. I will come back to this subject when I get an E-P3 profiled RAW converter

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Above: E-P2, ISO 800, Camera JPG Standard, NR normal. Below: Same picture, RAW conversion in Lightroom 3. (100% crop, Zuiko D. 50mm 1:2.0 Macro @ F4.0)