Nikon D70 Review
A short explanation of RAW to the uninitiated - RAW simply means data direct from the sensor's analog to digital converter (in the case of the D70 12 bits per pixel) which hasn't been processed in any way. The actual RAW file written to the storage card consist of a header which contains the current camera settings (parameters, exposure, white balance selection etc.) followed by this RAW data itself. The D70 writes RAW files in Nikon's .NEF compressed format which produces RAW files around 5.4 MB in size. RAW is considered to be 'the digital negative' as it represents the unaltered image data directly as it was captured and can therefore be processed in many different ways. (Note that the compression used for NEF files is lossless, it's a bit like Zip compression).
Unfortunately there is no industry standard for RAW (lots of reasons for this, not least of which are the variances in sensor design and image processing). This means you can't view RAW files in most photo applications like you can with JPEG (although more and more are adding specialized RAW support).
To convert RAW images you have an expanding range of options, supplied with the D70 is the new Picture Project application (the successor to the long running Nikon Viewer) which has basic RAW conversion with digital exposure compensation and white balance adjustment. To go further with RAW you will need to use either the excellent Nikon Capture (currently at version 4) or a third party RAW conversion application; these include Adobe Photoshop CS (although it doesn't yet officially support the D70) and Phase One's Capture One (again official D70 support coming soon).
PictureProject or Nikon View?
As you will have already read I wasn't impressed with PictureProject 1.0 and chose to use the (free) Nikon View 6.2.1 in the comparisons below, as it turns out they appear to have the same RAW processing engine, the primary difference is that Nikon View Editor allows for adjustment of white balance and digital exposure compensation and it allows for output as TIFF which is important for our comparisons.
JPEG vs. RAW (Nikon View Editor) vs. RAW (Nikon Capture Editor)
Below are two 100% crops taken from images shot within seconds of each other. The first crop is from a Large / Fine JPEG straight from the camera, the second from a RAW converted to TIFF using Nikon View 6.2.1 Editor.
|JPEG||RAW (Nikon View Editor)|
You can see a clear difference between in camera JPEG and RAW converted by Nikon View Editor. Clearly Nikon View Editor's processing algorithms implement a moiré reduction algorithm which removes the 'maze like' moiré visible at the highest resolutions. The RAW image also appears to extend resolution (or at least a representation of detail) beyond the extinction resolution of the JPEG image. However it is also worth noting that the halo sharpening artifact does appear to be slightly move visible on the Nikon View Editor converted image.
RAW: Nikon View vs. Nikon Capture vs. Adobe Photoshop CS
Disclaimer: Adobe Photoshop CS does not officially support the Nikon D70 although it will open D70 .NEF files. As you can see from the crops below Adobe Photoshop CS can't (at the moment) match Nikon Capture Editor for absolute resolution, nor elimination of artifacts, however I do prefer the crisp appearance of the numbers on the chart and the lack of sharpening halos. Lets hope Adobe will add full support for D70 RAW soon.
|RAW (Nikon View Editor)||RAW (Nikon Capture Editor)||RAW (Adobe Photoshop CS)|
Nikon View Editor sharpening issue?
While reviewing the D2H we spotted a problem with Nikon View Editor and Nikon Capture which rendered Auto sharpening incorrectly. This appears to have been fixed in Nikon Capture 4.1 with D70 RAW images, however it's still there in Nikon View Editor 6.2.1, there is no option to disable sharpening or decrease it below the 'Auto' level Nikon View Editor has chosen. We couldn't select an option which would deliver the same results as Nikon Capture Editor or in-camera JPEG.
|Sharpening: Auto (adjustment Off)||Sharpening: Low|
|Sharpening: Medium||Sharpening: High|
RAW vs. JPEG appearance
Below you will find two images, the one on the left taken as JPEG straight from the camera, the one on the right a JPEG converted from a RAW file using Nikon Capture Editor 4.1 (default settings). The RAW converted image has a slightly sharper appearance with a little more contrast, color balance is similar.
Settings: Parameters: Normal, ISO 200, Nikkor DX 18-70 mm
|JPEG||RAW (to JPEG using Nikon Capture Editor)|
|2,612 KB||1,606 KB|
RAW latitude (digital exposure compensation)
We estimate there to be between 0.5 and 1.0 EV of latitude above the normal clipping point of an image captured in RAW mode. This allows for the recovery of some detail in a RAW image which has been accidentally over exposed. As you can see in the image below, applying a -1.0 EV digital exposure compensation in Nikon Capture recovers some detail and the correct color of the brickwork.
|Default exposure||-1.0 EV digital exposure compensation|
Nikon 'Digital DEE' (digital 'fill flash' / digital dodge and burn)
Nikon Capture 4.1 provides Nikon's "Digital DEE" (Digital Exposure Extender) which can be used to enhance shadow detail and slightly darken highlight areas to produce a more balanced exposure or retrieve dark details. This is very similar to the 'Shadow & Highlights' feature in Adobe Photoshop CS and 'X3 Fill Light' in Sigma Photo Pro 2.0. Applying a Shadow adjustment of 20 to the image really lifts it, restores dark detail and produces an overall more pleasing image.
|Default exposure||Digital DEE: Shadow adjustment 20|