Street Photography Magazine

T

he top dogs among the latest

high-resolution cameras to hit the market

are the 22-megapixel Canon EOS 5D Mark III,

and the Nikon D800 and Sigma SD

models, with their record-breaking 36 and

46-megapixel sensors.

Sigma SD1 Merrill

Let’s start by putting the Sigma numbers

straight. The manufacturer arrives at the

massive 46-megapixel figure by counting

the pixels on all three of the sensor’s

light-sensitive layers. These capture light

separately from each of the three primary

colors (red, green and blue), instead of using

a ‘Bayer Pattern’ grid of color filters to colorize

the monochrome light that reaches a

conventional image sensor. This technique

provides the camera with ‘real’ color values for

all three color channels for each individual

pixel, thus increasing the effective resolution

and reducing the incidence of moiré

effects. Unlike conventional sensors, which

interpolate color data from the information

contained in neighboring pixels, the Foveon

sensor doesn’t require the use of a low pass

filter – a component that reduces the amount

of incident light that reaches conventional

sensors.

The resulting images measure ‘only’

4704 x136 pixels (i.e., 14.8 megapixels) but,

because they are not interpolated, they have

extremely high effective resolution. Our test

results (measured at optimum aperture) back

up this theoretical advantage.

However, the SD1 also has its drawbacks,

and exhibits extremely long save times,

especially for sequences of RAW images. This

a real disadvantage, as the camera’s JPEG

engine is not particularly effective, and

produces obvious color errors, reduced

dynamic range and burned out highlights,

making RAW the format that most

photographers will choose. Here too, Sigma’s

clumsy and non-user-friendly Photo ProRAW

conversion software detracts from the

otherwise speedy nature of the digital

photographic medium.

High ISO values are another weakness.

The SD1 produces obvious color errors in

monotone image areas at ISO 200 and above,

making this value the upper limit for viewing

monitor images at 100% magnification. Color

errors spread to gray areas above ISO 800,

and higher values produce marbling effects.

Above ISO 3200, the camera produces muddy

luminance noise and horizontal banding.

All in all, the SD1 is a highly specialized

camera with a limited target market, and

will appeal mostly to enthusiasts who are

prepared to accept its shooting limitations in

order to get the most out of its extraordinarily

high resolution and moiré-free images.

Prospective buyers should also be aware

that the SD1’s feature set is relatively modest

for a camera that costs US$2,300. Its monitor

is bright and can be viewed from a wide range

of angles, but has only 460,000 dots of

resolution and no live view. The camera lacks

a separate control panel display, and

autofocus and burst shooting rates are very

slow. There is no video mode at all.

If you are prepared to accept these

limitations, you will be rewarded with a

well-built camera with good handling and the

potential to shoot extremely sharp images.

The range of Sigma lenses is enormous, but

you should use only the best of these if you

want to use this unusual camera’s potential to

the full.

Nikon D

The same is true for the D800, Nikon’s new

36-megapixel full-frame monster. Unlike

the Sigma’s ‘divided-by-three’ resolution,

the Nikon delivers genuine 36-megapixel

resolution and 2,546 line pairs measured

over the height of the image frame,

presenting our lab technicians with a real

challenge. Our tests produced a value of

2,150  lp/h under ideal wide-aperture

conditions, which equates to 88 percent of

its theoretical maximum resolution, and our

test images confirmed our expectations with

regard to detail. Having said that, you need

to use the best possible lenses and plan your

shoots carefully to make the most of the

camera’s potential.

The Nikon sensor’s high pixel density

produces more noise than its lower-resolution

competitors, and cannot compete in terms of

maximum contrast above ISO 400. With the

exception of the Sigma, the D800 produces

less satisfactory signal-to-noise and visual

noise results than all other cameras in our

test at virtually all levels up to ISO 6400.

Nevertheless, the D800 produces great visual

results, with clean, well-defined images,

minimal roughness in monotone areas and

clear edges all the way up to ISO 800,

providing good image quality at 100%

magnification. Image quality begins to

deteriorate at ISO 3200, with increasing

luminance and color noise and reduced

texture and detail rendition showing up in our

test images. Resolution values start to lose

ground at this point too, and noise begins to

increase appreciably at ISO 6400. In real-world

situations outside our clinical lab conditions,

the D800 produces convincing, reliable results

straight out of the box.

The D800’s clear, bright viewfinder

displays 100 percent of the frame at 0.7x

magnification, and is directly comparable with

those built into the Canon and the Nikon D4.

The monitor comes with a reflective but

removable protector and has a slightly larger

(3.2-inch) diagonal than its predecessor. The

monitors in all four pro and semi-pro models

in our test are fixed, and the D800 is the only

camera in this test with a built-in USB 3.0 port.

Camera Test | SLR and System Cameras

The c’t test shot contains a number of serious technical challenges as well as some random

objects that were selected for their high recognition value. The details mentioned in the test

results are outlined in red.