The "sunny 16" rule, camera meters, even simplified zone system modifiers, all work extremely well in the right hands.

If it works for you, it's the right thing to do,

There is a leica 50mm f1 Noctilux lens for rangefinder, and there has been a Canon 50mm f0.95, which used to be referred to as the "Canon Dream" I think.

I don't think many of us need lenses with apertures such as these!

It's all to do with viewfinder magnification. The 55mm will give an approximately life-sized image and the 50mm just slightly less. I would be amazed if you could discern any apparent perspective difference between the two though!

The theoretical "standard" focal length according to the "rule" is a dimension that equates to the diagonal of the format. For 36 x 24mm format this works out at around 43mm.

In really bad conditions, I use the camera one-handed and use the other hand as a shield for the eyepiece...but that is "in extremis" and normally not necessary.

The hat is actually quite a good idea!

I've bought plenty of non-Pentax lenses over the years, and I think there are only a very few that reach the Pentax quality levels.

It would be fantastic if I'd known at the atrt that I wanted pentax branded lenses, I would have saved a fortune. However, life ain't like that and there is a learning curve to negotiate.

A good lens to start with on the *istDs is the bundled 18-55mm, which, although a little soft wide open, crisps up nicely when stopped down and is capable of producing excellent results. It is also very low cost when purchased with the camera.

Otherwise, perhaps keep a look out on eBay for a modestly priced but tidy Pentax lens or two. For the easiest use, choose one with an "A" setting on the aperture ring, or one of the new lenses with no aperture ring.

Even on a budget I believe that buying Pentax will save you money in the long run, but it's better to have a couple of lenses you can afford and actually take some pictures. So whatever you decide, shoot lots of images and have fun!

If you need more help, just use the forum and there will be lots of help from us all.

The Pentax K mount adapter has no extension, but lies flush within the mount. This is essential so that you can still focus on infinity.

They are less than £15 new, and are still available from your dealer.

Screw the adapter on to the back of the lens. Then bayonet the combination onto the camera. When you unscrew the lens the adapter will remain on the body - you have effectively turned a bayonet body into a screw mount one. Lenses can now be screwed on and off as you wish.

When you have finished with the adapter, depress a small spring in the adapter and carefully rotate and remove it from the body.

I think I would just open the lens using the aperture ring to focus, and then close it again, rather than using the A/M switch.

So if you set the auto/manual switch to manual, the lens will stop down to the set aperture. Does this mean that the digital bodies will then operate quite happily in aperture priority?

OK, focusing would have to be done wide open, then the aperture just turned to whatever you wanted and then the camera would set the shutter speed. That would be easier than using the stop down lever for a bayonet lens, wouldn't it?

There is a wealth of information and opinion on both those sites - very interesting and useful.

IMHO there is no substitute for trying things out for ourselves, because lenses are complex and make many compromise choices and each photographer's requirements may well be different.

So we all ens up with our favourite lenses!