I have just purchase this lens and the sharpness and lack of distortion is amazing at the telephoto end. Shame it is not the same at the wide end. To be honest, I have a sigma 28-300 super zoom which can perform better at 28mm than the DA can at the same setting and that is saying something.

The SDM doesn't seem to be as fast as I expected but it is virtually silent and accurate.

For the price I paid for this lens I was expecting more but it wasn't a waste of money because most of my work uses around the 50mm for portraits

Is there a split screen for the DL2 which is similiar to that of the MX models.

I'm having problems with autofocus and i've seen the screens for the viewfinders but there's a few of them, and PENTAX is only saying the K10D has one, but i'm sure there's one for the DL2

Altering the white balance is post-production can offer fine-tuning, where as filters, regardless if it's 81 or 85 only offer 3 levels, A, B and C.

Filters, regardless of the quality, is just another piece of glass with flaws in front of the senor. More distortion, reduced picture quanlty. Granted, it may not be noticable but its still there.

Of course there's the cost of well. 81 and 85 each with three level for each size lens adds up. I suppose there's always step-up rings and cokin.

At the end of the day, I only used three filters. ND, polariser and a UV. The UV is just there for lens protection but I always remove it first for professional use. That's all you need!

Just to add to johnriley's description. The reason why lenses don't have one simple element is because that single element would act like a prism when it refracts the light, spliting up the light into red, green, etc. So it needs another element to counter act the prism effect, which produces another effect, so we need another set of elements to counter act that effect and so on until the end image is near perfect. How perfect depends on the quality of the elements.

BTW I thought we were talking about depth of field

I do apologies, it was the way your describe the two lenses f1:1.4 and f1:4, guess I need to recheck my glasses. However, you need to re-check your brain cell. For the last time, it has nothing to do with the filter size but the front element lens. Please read ChrisA’s description very careful.

Did I not say 'assuming that you are correct in saying that they are both f1.4'. This was not a statement that lenses are not both f1.4

Like I said, it is the front lens and not the filter size. However, a 100mm f1.4 lens with a 49mm filter size, hmm!

Galoot is right by saying it has nothing to do with the filter size. However it is the diameter of the front lens that has something to do with it but for the obvious reasons the filter size can never be less than the diameter of the front lens.

Take a look at the 100mm and the 50mm lens, assuming that you are correct in saying that they are both f1.4, then the 50mm front lens should be half the size of the 100mm. Either that or the 50mm lens does not use all of the front lens

WOW!

Some desciption there!. Do you want to come to my photography class, you can reduce a few photographers to tears

Sadly, discipline is lacking with most digital users that never started with film. I've seen it far to often in my class. 'Ohh, a distraction, I think I'll clone/crop/paint/blur/paste/photoshop it out'. Pretend photographer is the better phrase

...and so it goes on just like CD and Records. At the end of the day, what do you prefer? Is there a quality difference or just different character attributes?

What made CD win over Record, was it the quality or the convenience of press buttons.? What will make digital win over film, is it the quality or the convenience of instant preview and not waiting an ice age for development?

Personally digital is better for me because it doesn’t cost me £5 or something for every 27 pictures to see my work. I still use film for B&W for professional use because I’ve got my own B&W darkroom and that is what the client specifies.