When you are viewing, at open aperture, the f1.7 lens just lets in more light and the screen will appear brighter and easier to focus manually.

As for pictures, that's spot on, each lens surface shows slight reflection even with the SMC coating. Even at 0.2% reflection per surface, a six element lens represents far less light scatter than a 15 element zoom. Without the coating the 15 element zoom would be almost unuseable. (I say almost for those who remeber the 1959 Voigtlander Zoomar)

Less elements mean less light scatter and therefore higher contrast. Higher contrast means better visual sharpness.

Personally, I find that digital capture takes us into different territory as far as lenses go. On film, I would have used prime lenses, on digital I seem to be happy with modern zooms.

The 50mm lens does indeed make a fine 75mm-equivalent portrait lens, but I have one as part of my kit and it hardly ever gets used. The zooms do get used, and they are so good that any difference can be pretty much theoretical.

The 35-70mm f4 is not as good optically as the 50mm, but it is still very good and is far more versatile.

If you can, get both, and then if you don't like one of them there is always eBay...

I guess you ignore the Birthday Girl at your peril....

Sounds like a great day.

It might be a bit easier to shoot things like this as JPEGs from the start - less processing and less drive space, also perhaps to stick to 8 bit. Add Photoshop for its greater flexibility and you'd be pretty well set up.

A good way to practice though - not much can be more challenging than photographing a grand-daughter's party!

I think the ideal zooms are:

SMC Pentax-A 35-70mm f4
SMC Pentax-A 24-50mm f4

The constant aperture is useful and the quality is excellent.

As a general principle it is far better to do as little sharpening as possible in camera. Photoshop is much more sophisticated. A small pre-sharpening can be done in PS at the start, but usually the Unsharp Masking is done as the very last step before saving the image as a TIFF. By doing this the creation of unwanted artifacts in the image is minimised.

Excellent news indeed, thanks for the info George.

JUst a thought about using colour correction filters.

If we do this using AWB then the colour of the light will change and the AWB will try to compensate, which is self-defeating.

I think we need to use Daylight setting for this. Or ditch the filter and set the camera to Cloudy, which should be close to the effect of an 81A filter, nice and warm.

We have two approaches to this. The first is an Epson P-2000, which is the best portable HD I have seen so far. Superb build and a terrific 3.8 inch screen. 40GB.

The second approach is our new laptop, which we will use both to store images on the move and also to burn back-up CDs as we go. This makes the Epson a bit less essential, but that's progress!

Black means there has been no exposure at all, so maybe the shutter isn't always firing. The way to tell is to open the camera back and keep operating the shutter to see what happens. If sometimes it doesn't fire, you have your answer.

About the only thing I can think to do if that is the problem is to check the battery contacts, and indeed always try new batteries anyway when any electronic camera shows any sort of fault.

Otherwise, it's off to the repair shop!