JPEG/TIFF Image Size & Quality
The 880 offers a reduced number of image size / quality combinations than the 990. Gone is the 3:2 ratio size of 2048 x 1360, now a more straightforward FULL (2048 x 1536), XGA (1024 x 768) and VGA (640x 480). All of these image sizes may have three JPEG quality levels (FINE, NORMAL and BASIC) plus an uncompressed TIFF mode (HI) at 2048 x 1536.
|Standard Test Scene|
To give an impression of what each combination of image
size and quality produces the table below is a cross reference of image
size against quality with an original image available for each, all images
were shot within seconds of each other of the same subject. Please note
that the TIFF images are VERY large (7.6 MB zipped) please only download
these images if (a) you really need to and (b) you have the bandwidth
and intend to fully download the image, otherwise you're wasting bandwidth.
Images below are 100% cropped 480 x 200 area of the image.
|2048 x 1536|
9,327 KB (Zipped 7,799 KB)
|1024 x 768|
|640 x 480|
For all intents and purposes JPEG FINE and TIFF HI are hardly distinguishable, and for casual shooting JPEG NORMAL is also a fairly good bet, although obviously the compression algorithm is having to throw away much more image data to produce those <800 KB JPEG files.
It's fairly interesting as a reviewer to see manufacturers react to consumer requests, we moaned and complained about not having a TIFF format, now we have one it's almost unusable as it generates huge file sizes (I'm not sure I know anyone who regularly shoots TIFF on a 990). I think it's time we sent a new message to manufacturers design departments... We want RAW mode on all digital cameras, the ability to take a "digital negative" out of the camera which hasn't been touched by the cameras internal processing algorithms. This has many advantages: smaller file sizes (at 8-bits per channel a 2048 x 1536 RAW would be approx. 3 MB, at 12-bits per channel this would increase only to about 4.7 MB), because the images are not white balance corrected (but would rather be corrected at time of import / acquire) you can choose / correct the white balance at a later date, you can also perform more sophisticated processing on a PC/Mac than you ever could inside the camera... So, RAW mode please :)
ISO (Sensitivity) Adjustment
ISO equivalence on a digital camera is the ability to increase the sensitivity of the CCD to allow for faster shutter speeds and/or better performance in low light. The way this works in a digital camera is by "turning up the volume" on the CCD's signal amplifiers, nothing is without it's price however and doing so also amplifies any noise that may be present and often affects colour saturation. Below are three images, in order ISO 100, 200 and 400.
|ISO 100, 1.3s, F9.4|
|ISO 200, 1.0s, F9.4|
|ISO 400, 1/2s, F9.4|
As we'd expect noise increases, though it's still manageable and doesn't detract too much from the overall image, colour saturation decreases (as side-effect of pushing the output of the CCD).
Image adjustments can be seen as altering the parameters given to the internal image processing algorithms before the image is written out to the CF card. The 880 has the same range of image adjustments first seen in the 990. The effect of the adjustment is displayed in the LCD preview before you shoot. Below are six samples representing the six possible Image Adjustment modes.
It has been noted that Nikon's Image Adjustment algorithms are like S curves in Photoshop, that is although the look of the image is changed the overall dynamic range is not affected and you should be able to return any of these images back to the "Normal" look (apart, obviously, from Black & White).
|Less Contrast||Lighten Image|
|Darken Image||Black & White|