There should be very little on a rectilinear lens, but I suspect the 12-24mm will be even better as it is quite exceptional in that respect.

There are two different things here. Quality is possible with plastic and a light lens correctly made is in one sense no worse made than a metal one. In fact, it might hold its quality for longer in some circumstances.

The metal lens is another beast altogether, made using traditional techniques and to some degree probably hand crafted. Hence the Limited range. But we can see what happens to cost when these standards are applied.

To be honest, for what they are, I don't think that any of the Limited range are expensive at all. If you think they are, just mull over the Leica price list....

The problem is that usually our opinions are based on owning one example of a lens. I'm fortunate to have owned several of many lenses old and new, but one second hand lens can be damaged, might have been dismantled by an over-enthusiastic owner, we really don't know.

Modern lenses are very, very good though and in terms of quality on digital many classic lenses will struggle to keep up.

Wide aperture lenses are easier for manual focusing because they snap in and out more obviously. All lenses need to be focused accurately, but the amount of error in AF systems and in our eyes is usually more than catered for by depth of field. At wider apertures DOF is onviously much reduced. so accurate focusing is more essential. There will be errors and we won't get 100% spot on focus, but some is also due to subject movement. Don't forget that when we focus even on a portrait subject's eyes, the subject is wavering about as much as the photographer.

The 12-24mm is a superb lens, and you can take all sorts of subjects with it. It's especially suitable for architecture as the drawing is excellent, so straight lines remain so. You could use it for some kinds of portraits, but wide angle lenses are generally not suitable for this because of distortion from the closer viewpoint.

The choice probably remains wide aperture lens for low light, wider angle or longeer telephoto, or macro. The final choice depends on what you want to photograph.

Certainly are, with maybe a bit of haggling to secure all three?

Try, see what you think, eBay the ones that don't gel. This doesn't necessarily mean the ones you resell will be sub-standard, it's just that lens choice is a personal thing and some lenses will suit your photographic style better than others.

The K-5 is amazing value at the moment and will give you a big jump in various aspects of performance.

Excellent amilid, being a Pentax User has unexpected benefits at times...but we need to keep our eyes open and move fast!

Photography is expensive, but in many ways we can recoup the costs to some extent, at least mitigate them.

Not everyone was impressed when I invested in some expensive Pentax lenses. In the end they have served me well and I will have ended up with the two limited lenses that suit my style (43mm and 77mm) and they won't have cost me anything.

There's nothing immoral about buying what we want and reselling at a profit if we want to. Of course, HMRC will want their share of any profits, so it's worth being careful not to become a business and end up paying tax. The very act of buying to sell for a profit on eBay makes us a business as I understand it, but that's a whole other issue.

Interesting, although to be fair no-one has tried to profit by selling back to the members here. No doubt they will end up on eBay.

The only way Amazon could stop that, if they wanted to, would be to make an offer "limit of one per customer". However, as far as Amazon are concerned they probably sold out their offer and were happy to do so. Maybe the new batch will be relabelled Pentax Ricoh, which was possibly the point of it all.

For portraits, I would suggest the 50mm f1.4, 55mm f1.4, 70mm f2.4 or the 77mm f1.8, all of which have a place.

In 35mm film terms, these are equivalent to 75mm, 85mm, 105mm and 120mm (rounding to common lens types) so it then depends on your taste in short telephoto lenses.

I always found on film 85mm too short, so for me the ideal on digital is the 70mm or 77mm. It's possible to get nice close crops with these. They are also excellent for landscape shooting.