Previous page Next page


RAW (NEF file format)

RAW data represents a per photosite (pixel) value (12-bits per pixel in the case of the D1x) which comes directly from the CCD's analog to digital converter. No in-camera processing is performed on this data before it's recorded in the RAW fie. To understand the RAW format completely you must understand that a digital camera's sensor only captures one colour per pixel (in the case of the D1x, red, green or blue). When shooting in JPEG or TIFF modes a full 24-bits of colour per pixels is created by interpolating colours from surrounding pixels, in the case of RAW this interpolation takes place outside the camera using special software.

The advantages of RAW image format are:

  • It's a lossless format which creates smaller files than an equivalent TIFF file:
    RAW - 4028 x 1324 x 12 bits = 7,812 KB
    TIFF - 4028 x 1324 x 24 bits = 15,624 KB
     
  • It can record 12 bits of data per pixel giving it more 'headroom' than a TIFF or JPEG file.
     
  • The RAW image data is untouched, it's as close to a "digital negative" as you can get. Camera settings information such as selected white balance, sharpening and tone are recorded in the image file header but have not been applied to the image. This means you can make changes to things like white balance, tone, sharpening, colour, exposure compensation (to a certain degree) AFTER the shot has been taken.
     
  • Exposure information and camera settings are recorded in the image "header" which allows conversion software later to apply the image settings selected at the time.

The disadvantages of RAW image format are:

  • Currently their isn't a standard RAW file format thus each manufacturer has their own proprietary layout. Therefore you can't open these image files with a normal photo package without using a special plugin or module to convert the RAW file.

Read more about RAW in our glossary.


Nikon Capture 2

Nikon Capture 2 is the latest incarnation of Nikon's image manipulation and processing package designed to be used exclusively with the D1x (or D1, D1H). It allows the viewing, manipulation and conversion of the RAW (.NEF extension) format (as well as JPEG). Version 2 now offers several new features, not least of which is batch processing.

Here are a list of improvements to Nikon Capture 2, these are not my words, this is from Nikon:

Post Shooting White Balance

This new feature permits the fine adjustment of the color temperature of an image even if white balance was not properly set at the time of shooting. The control places a number of options for setting white balance including sampling of one point, an average of a number of points or setting the color temperature manually. This removes stress from the shoot as the photographer can work in the assurance that when shooting in NEF (raw) format, any white balance adjustments can be made with great precision afterwards in Nikon Capture.

Post Shooting Exposure Compensation

The 12-bit NEF (raw) file has a much wider dynamic range than an 8-bit RGB file. This dynamic range is sufficient to allow detail in white, overexposed areas to be recovered by a factor equivalent to about up to 2 stops. This new feature allows digital photographers to enjoy the kind of exposure latitude formally only available with colour reversal film.

Batch Processor

The new Batch Processing window in Nikon Capture 2 is an updated and improved version of the Autosave function - familiar to Nikon Capture 1 users - for automatic processing NEF (raw) files into JPEG or TIFF images. The new versatile batch feature has a host of options for file management including renaming and applying any saved settings to the images as they are processed. Image files may be moved or copied and can be saved in a variety of formats including TIFF, (16 and 8 bit) JPEG and NEF.

LCH editor

The LCH editor brings a new dimension to color correction, particularly in the handling of color casts. By allowing selection of lightness, hue and saturation according to an image saturation curve, neutral areas can be left neutral whilst only more saturated areas are affected by the comprehensive color controls.

In use

Above you can see Nikon Capture 2 with all of its windows open, there's the preview image as well as full exposure information, this image can be zoomed and panned and the small 'birds eye' view windows allows you to navigate quickly when zoomed. Image Adjustments are now controlled by the new Image Adjustments window which allows you to easily enable or disable a particular adjustment to see its effect.

There are a wide variety of adjustments from output size, simple colour balance (contrast, brightness, channel compensation) to full curves adjustments, unsharpen mask and white balance correction. Because Nikon Capture 2 is working from the RAW CCD data it can adjust settings such as sharpening, tone and white balance which would otherwise have already been applied to JPEG or TIFF images. Probably one of the most powerful adjustments is the 'Advanced RAW' window which allows you to make changes to hue, colour mode (sRGB / Adobe RGB), tone, sharpening and exposure compensation.

Conversion Examples

Original NEF (7,874 KB) Original NEF (7,900 KB)
JPEG #1 (1,477 KB) JPEG #2 (1,835 KB)
JPEG #3 (1,738 KB) JPEG #4 (2,440 KB)
  1. Original converted from NEF with no adjustments, sRGB
     
  2. Original converted from NEF with no adjustments, sRGB (Obvious white balance problem)
     
  3. Sharpening Low, Unsharp Mask: 37%, 3%, Less Contrast, Gray Point White Balance, +0.5 EV compensation, Black point compensation (curves), sRGB
     
  4. Sharpening Low, Unsharp Mask: 77%, 3%, Normal Tone, Mulit-point Gray Point White Balance, +0.33 EV compensation, sRGB

These examples aren't exactly stretching Nikon Capture's abilities, however they do show (especially the market scene) that RAW format provides you with the flexibility to perform changes to your image which would be either very difficult or almost impossible with JPEG or TIFF.

Batch Conversion

Once you have a set of adjustments you can save them into an adjustments file. These adjustments could then (for instance) be applied to a batch of RAW files using the new batch tool:

The batch conversion tool requires an image source (folder full of NEF files; it can also scan sub-directories), an image destination (this can be the same as the source folder), an output format (NEF, BMP, JPEG (JFIF or EXIF), TIFF (RGB or CMYK; 8 or 16 bit) and an 'Image Enhancements' set which can either be the current settings, a neutral setting (same as camera) or a pre-defined set (as described above).

The interesting thing about Nikon Capture 2's batch tool is that it can be set to 'periodically check for new files', this means you could have a network server running a minimized copy of Nikon Capture 2 constantly monitoring a pre-defined directory for automatic conversion of NEF files which are 'dropped' into it. Interesting. Click here to see an animation of the preferences dialog box.

Overall Nikon Capture 2 is now far more powerful than it's predecessor and at the new lower price is a must have for all D1x owners (it's a shame it's not bundled really).

Nikon Capture 2 performance

One important item when using any image manipulation application, especially dealing with RAW images, is how fast it is. The following timings were taken on my desktop PC (dual processor Pentium III 933 Mhz, 1 GB RAM, Windows 2000), Nikon Capture 2 only utilised one CPU during our tests (thus, no advantage having a dual processor machine), all settings were defaulted:

  • Load and display NEF - 6.92 seconds
  • Save As JPEG Excellent Quality - 21.3 seconds (5,487 KB)
  • Save As JPEG Good Quality - 19.3 seconds (1,648 KB)
  • Save As TIFF RGB (8-bit) - 18.5 seconds (17,326 KB)

Nikon Capture 2 Camera Menu / Control

With the camera connected via Firewire (IEEE 1394) the Camera menu and Camera control window become available. The first and probably most useful feature is custom settings:

This window allows you to change any custom setting on any of the cameras memory banks. This interface is clearly quicker to use than the on-camera menus. You can also save these settings to a local file.

Additionally there are a few camera settings which can be altered when connected:

You can also set the camera's internal contrast curve.

The Camera Control window (below) allows you to control the camera remotely, it gives you a readout of exposure details (same as the viewfinder LCD readout) and you can change almost every setting you can from the external camera controls. Hit the 'AF and Shoot' button to focus and take a shot (review is shown live) or just 'Shoot' to just take a shot at the current focus.

Previous page Next page

Comments