I'd take a 14mm F2.8 if it were about half the price it currently is - a 16mm F2 or F2.8 would also be useful. I've already got a FA 50mm F1.7 but, if anything, having that in the range would be more useful than it was in the film days.

Canon have a few decent priced primes in their range, although nothing wide and cheap, that I wouldn't mind seeing equivalent priced Pentax equivalents for.

20mm F2.8 for £318 - Pentax equivalent is the 21mm F3.2 for £399
24mm F2.8 for £314 - no current Pentax equivalent
28mm F2.8 for £137 - no current Pentax equivalent
35mm F2 for £185 - no direct equivalent, 31mm F1.8 is £799
50mm F1.8 for £69 - no current Pentax equivalent, Pentax 50mm F1.4 is £169
50mm F2.5 macro for £189 - Pentax 50mm F2.8 is £349
85mm F1.8 fr £259 - no direct equivalent, 77mm F1.8 is £699, 70mm F2.4 is £449
100mm F2 for £299 - no Pentax equivalent

(all prices from warehouseexpress website)

Ok the Pentax limiteds will be better performers however for many of us (including me) the cheaper lenses would be good enough. In particular the Canon 50mm F1.8 and 85mm F1.8 are particularily good value.

Despite still much prefering the handling of Pentax cameras to Canon ones I did very seriously consider going for a Canon when I first went digital, primarily due to lens prices and availability (including 3rd party support).

If you're a Canon or Nikon user you can have a 12-24mm F4 for £350 as you can buy the Tokina version...

I used to have one of those - it's a very interesting camera and capable of excellent results if used carefully.

With current technology the sensor size is a factor in the amount of noise especially at higher ISO's - that's one reason why the 7MP sensor in my wife's little point and shoot produces results that are very, very much poorer than the results from my 6MP DS.

Even if we ignore the fact that there are loads of lenses already in circulation for the old 35mm equivalent frame it's clear that it's much easier (and cheaper) to make wide and ultra-wide lenses for the larger sensor than it is for APS-C - that also impacts fast "normal" lenses. For film we can get a SMC-FA 50mm F1.4 for £170 but to get anything like an equivalent for digital we're looking at perhaps the Pentax 31mm F1.8 (an astounding £800), or perhaps a Sigma 30mm F1.4 (£270). Ok the 31mm is a limited lens and better made, however the 50mm F1.4 (or even the cheaper 1.7) is an excellent lens and, for me at least, certainly good enough as well as being significantly faster.

The issue with wide lenses does have a positive APS-C trade off in that it's cheaper to make long lenses and that's great if that's your thing - however I tend to be a wide angle shooter.

Despite having bought a few digital specific lenses which I enjoy using (Sigma 10-20mm, Pentax 10-17 and Pentax 16-45) I'd still be quite happy to see a return to the full 35mm equivalent frame. To that extent I'm still keeping hold of one lens (Tokina ATX-Pro 20-35mm F2., which more or less useless, with APS-C "just in case" although I've offloaded several others (24mm F2, 35mm F2, 28mm F1..

I mostly shoot wide angle and while there are several digital specific lenses available now that cover it (both the Sigma 10-20 and Pentax 10-17 are wider than I ever had with film) they are quite expensive considering they are also fairly slow plus there are very few wide or ultra-wide angle primes available.

It's my intention to stay away from APS-C only lenses as much as possible because I hope that we do see a move to full (35mm) sized sensors in consumer specification digital bodies. This is mainly because the area most adversely affected by the smaller sensor size is wide angle, and that's what I use most often.

So far I've only two APS-C only lenses (Sigma 10-20 and the Pentax 18-55) and don't particularily intend adding any more, plus I'm keeping hold of the likes of the Tokina ATX-Pro 20-35mm F2.8 (great as an ultra-wide on 35mm but less useful with APS-C) just in case.

My experience with the pro-spec Tokina was that they were pretty good, and back in the days I was buying them they were the only 3rd party manufacturer that fully supported Pentax with F2.8 zooms.

A Tokina 16-50 F2.8 is definitely a lens I'd be interested in, but it'll depend on how the price compares with the Pentax 16-45 F4. From experience I'd expect the Pentax 16-50 F2.8 to be very good, but also very expensive.

Now there is an idea - wonder if I'd get a cheap deal? Probably wouldn't want me though as I'm a slut when it comes to lens manufacturers and I'm not faithful...

I very nearly had the Pentax 12-24 as well because my wife is in Singapore at the moment and it's selling for £400 there. I was very tempted however they had the 10-17 fisheye so she's got me one of those instead.

The Sigma is a lovely lens though. It's very sharp, no sign on CA in any shots so far, good for flare and it seems well made and handles fine. Here are a few recent examples with what has become my most used lens:



Held the lens down near the ground and shot without looking through the viewfinder



Lenses this wide are great for candids because your subject (in this case my camera shy daughter) doesn't immediately clock that you're taking a picture when you don't have the camera to your eye.



My son bouncing on the trampoline - again not looking through the viewfinder by just holding the camera underneath him as he bounced.


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I've been using Cokin P on my 10-20 Sigma and it works ok, however you have to be very careful with the alignment if using the normal filter holder. I use a holder that is cut down to hold just a single filter and that's fine even for very wide angles.

The Sigma is a fair old size but it seems to match well with the DS body and they feel right as a combination.