Sigma DP1 and Olympus E3 - A Simple Comparison

[tomcat]

This is a simple comparison of the image quality of the same scene as taken by the Sigma DP1 and the Olympus E3 (with the ZD 12-60mm set at 14mm focal length).

While some might say that it may be unfair to compare a prime lens (on the DP1) with a zoom lens (ZD 12-60mm), this is more of a practical usage comparison rather than an apple-for-apple one. This is because I intend to use the DP1 as a second camera for landscape photography during my holidays overseas. During such trips, I would be using the E3 with the 12-60mm as my primary DSLR for landscape photography and the DP1 would be the supplementary camera. In such a situation, don't know about others but I would definitely be interested in knowing how the 2 cameras would perform when capturing the same scene as such. Hence, this comparison...

Both cameras were mounted on the same tripod to keep the position the same. In both images, the cameras were focused on the distant HDB blocks in the centre of the frame and Aperture Priority mode was used with aperture fixed at f/4.0 for both cameras, ie wide-opened in the case of the DP1. The shots were taken in RAW and developed with Capture One Pro (for Olympus E3) and Sigma Photo Pro ver2.5 (for Sigma DP1). The exposure was set to Auto during RAW conversion and the white balance was manually corrected. Other than that, no other changes were made. The Olympus E3 image was subsequently downsized to the same width as that of the DP1 for this comparison.

This is the scene as recorded by the Olympus E3 and Sigma DP1.

Olympus E3

The full-sized (down-sized to the same width as that of the DP1 image) image by the E3 can be viewed here:
http://www.pbase.com/pschia/image/96209904/original

Sigma DP1

The full-sized image by the Sigma DP1 can be viewed here:
http://www.pbase.com/pschia/image/96209905/original

100% crops of different parts of the scene are compared as indicated in this image:




As the proverb goes... "A Picture Speaks a Thousand Words"
I think the images speak for themselves, don't you think?

[theveed]

I think that has to do with the Foveon sensor not having an AA filter hence the sharpness... The DP-1 seems to be the closest thing to sharp film shots without PP.

Now I wonder whether an AA filter is that big of a deal... I mean, moire or sharpness... I prefer the latter.

[dorts]

Wow. The DP1 does seem much sharper. But there seems to be a tinge of motion blur on the E-3. Or is it just not sharp?

Is it possible to compare JPEGs as well? Maybe increase the sharpness value of E-3's JEPG output?

The DP1 colours definitely look washed out. But otherwise, my untrained eyes can't tell the difference in detail, besides that the E-3's image is more blurred.

[tomcat]

Originally Posted by dorts Wow. The DP1 does seem much sharper. But there seems to be a tinge of motion blur on the E-3. Or is it just not sharp? Is it possible to compare JPEGs as well? Maybe increase the sharpness value of E-3's JEPG output? The DP1 colours definitely look washed out. But otherwise, my untrained eyes can't tell the difference in detail, besides that the E-3's image is more blurred.

First of all, it is not likely that there was any motion blur for the E3 as it was mounted on a tripod. Secondly, the light intensity was so strong that the shutter speed set by the E3 for that shot was 1/1600s (the EXIF data are kept intact in the images for comparison for those who are interested). At that speed, I could have even handheld the camera and still not suffer from motion blur. Even wind-blur would not have been a problem in this case.

The DP1 chose to set a shutter speed of 1/1000s instead. I did not try to make both cameras use the same exposure settings as there could be reasons why the default settings are as they are for the respective cameras. For example, from my experience with the E3, I find that the E3 like to underexpose somewhat in order to preserve the highlights and it seemed to be the case here.... I find the image to be a bit too underexposed (and slightly too warm in white balance) for my taste as evident in the loss of details in the shadowed areas and I would have increased the exposure at least in the shadows if I were to carry out further post processing. Because of the AA filter, the image would also have to be sharpened more during post processing.

The DP1 on the other hand seemed to have over exposed a little bit as was evident in the lesser details in the clouds and the slightly less saturated colours. However, there were oodles of details in the shadowed areas which is somewhat lacking in the E3 version of the shot. In any case, increasing saturation slightly during post processing is not a problem at such low ISO speeds and I routinely do it all the time to make the image 'pop' for the DP1, SD14 and E3 images anyway.

[paisatge]

thanks Tomcat for the comparison.

I think DP1 sure displays more details. For example, i can see the shadow of the lines of the chairs in picture 2. The crop from E3 just shows shadow without any lines.

Wonder if this is due to, lens quality aside, the bigger DP1 sensor size.

[tomcat]

Originally Posted by paisatge thanks Tomcat for the comparison. I think DP1 sure displays more details. For example, i can see the shadow of the lines of the chairs in picture 2. The crop from E3 just shows shadow without any lines. Wonder if this is due to, lens quality aside, the bigger DP1 sensor size.

The lens could be a factor but the ZD 12-60mm is reputedly a very sharp lens too.
While the DP1's sensor is slightly larger than the E3's sensor, the real irony is that the native resolution of the Sigma image file is actually only 4.6M while that of the E3 is 10M. Usually, when we downsize an image, it tends to appear sharper. By downsizing the E3 file in this comparison to match that of the DP1, it should already be 'advantage' E3. Also, by keeping the aperture at f/4 for both cameras, it should again be another 'advantage' E3 because the DOF of the DP1 should be shallower than that of the E3 at the same aperture due to the DP1's larger sensor size.

[skopio]

Sigma definitely seems sharper. but the oly really looks underexposed. that said, save pixel-peeping, either would definitely be good for an overseas trip.