Quality Settings

What Quality setting should I use?

I've often been asked which Quality setting should be used, as it has a great influence on the number of pictures you can get onto a memory card. The Nikon 990 offers three different compression or "Quality" levels - Basic, Normal and Fine - with typical image file sizes of 400KB, 700KB and 1MB. Note that we are not talking "Resolution" here. Resolution is the number of pixels which make up the picture - normally 2048 x 1536 - although lower resolutions such as 1024 x 768 and 640 x 480 are also available and will result in smaller file sizes.
Here's my take on the Quality question....

The Basics

We've been using Nikon 900/990s for few years now, and we have always used the Basic setting. Yes, it would be nice to use a higher setting, but with the memory as expensive it was, with the need to take all storage with us, and without anything like the Digital Wallet, it was really the only choice.

However, like you, we first established that we could see minimal difference between the Normal and Basic quality settings. There are a couple of mitigating factors here.

Our pictures are almost exclusively for screen display and not printing. This means that for each screen pixel more than one photographed pixel will contribute, so errors will average out. If you were always zooming in to look at a small part of the image, any errors in Basic would be slightly more visible.
The Nikon implementation of the JPEG algorithm seems to be one of the best I have ever seen, and the file sizes are astonishingly small for the amount of compression done. If you try and make the same quality compression in your image processing program, for example, the file size usually ends up a lot higher. I attribute this to the fact that each CCD "pixel" is not quite sharp (it's an average anyway from R, G and B filtered pixels), so that the in-camera JPEG compression has a relative easy job to do, resulting in higher quality for the same compressed file size.

Where might this be different for me?

There are some circumstances where using Basic may be inappropriate for you:

If you print large images rather than viewing on the screen
If you use the lower resolution modes where the pixels are sharper
Possibly, when you shoot large uniform non-coloured areas (e.g. grey slate roof)

(I've only once seen the grey slate roof problem, and that when I had the combination of VGA and Basic. The JPEG compression has no colour information to offset the compressed grey levels).

Of course, if you have the time, you can check the picture on playback, and re-take if necessary. The great thing is with the small file size, when you are back home, you can keep all your "masters" as well as any cropped or reprocessed images. BTW, if cropping is all you do, use the lossless JPEG cropper, because there is no quality loss.

You might want to use Normal or even Fine if you know you are going to do significant processing or enlargement, or if you can see that the subject would benefit from the higher quality.