Choice

Just would like to ask members for there choice of lens for both portrait and landscape photography and may be the reason why they are your first choice.
Ian

Having a single lens for both portrait and landscape photography is tricky, because landscapes traditionally require quite a wide lens whereas portraits require a moderate telephoto. The closest you're likely to get to it is the Pentax DA 17-70 f4 (or alternatively the Sigma 17-70 f2.8-4 OS HSM, which is cheaper). This is wide enough for most landscapes, while being long enough for portraits. Its only challenge is that it is only f4, which is fine for landscapes (you'll be shooting at smaller apertures for depth-of-field anyway) but not necessarily the best for portraits (where larger apertures - f2.8 or faster - are normally preferred).

I use the Pentax 17-70 for landscapes, mostly, though I have been known to use the 60-250 or even the Bigma for them.

Portraits I use either a 50mm 1.7, the DA*50-135 or even the Tamron 90mm macro, depending on what I am aiming for.
I like the 50mm lens but as it is only manual focus it gets used less as my eyes get worse. The 50-135 offer a good range of lengths for portraits, and is fast enough for natural light indoors. The Tammy is a brutally sharp portrait lens, which I like for male subjects.

Like David says the 17-70 should be able to it.

I find I could use the DA*16-50 for portrait, haven't use it for landscape yet but I don't think that would be a problem. So lenses around that range wouldn't be a problem either.
And if you don't like wide then there are quite a lot of 24-70 lenses or around that range.

Funny enough I've used the DA*50-135 for landscapes also, so what's there to say about a focal length?

Sorry guys what I was trying to say is what would be your choice of lens to use in both situations not what one lens would suit both. Gwyn I have read the Tamron 90mm is a very good lens a freind of mine has one and he loves it. I have the Pentax 1.7 and have had some very good results with this lens.
Ian

I have Nokton 58mm (87mm equiv) which is great for portraits, the main reason I bought it. But its slightly too narrow for landscapes. However I shoehorn them in.

https://www.pentaxuser.com/forum/topic/anyone-use-a-50mm-for-landscapes--21021/p-0#comm_227905

I'd guess 50mm being 75mm on DSLR is about right for a close portrait.
40mm (60mm )would be a bit cosy.

Maybe 43mm would be a good compromise? I wonder if anybody makes a K mount lens in that length? You can squeeze a landscape in and get cosy for a portrait.

Ideally, you have a 21mm or 25mm or 28mm Zeiss for landscapes and the 58mm Nokton for portraits.

Alternatively save yourself £1.6k and stick with the 50mm F1.7. I've just bought a M version to go on the MZ-M but I may just try it on the K-7.

Portraits - FA*85
Landscape - DA*16-50

Portraits - 50 f1.7 / Tamron 90mm
Landscapes - 16-45mm

Which do you prefer between the 50mm 1.7 and the Tamron 90mm I have thoght about buying the Tamron a few times.
Ian

The Tamron 90mm is a very good lens as are the Pentax DFA 100mm and Sigma 105mm macros - the differences between them are so slight that they are often referred to collectively as '100mm-ish macros' (i.e. it doesnt matter for image quality which you get - buy whichever is on the best deal or 'feels right' for you). I quite often find my Pentax DFA 100 too long - ie I can't get far enough away from the subject - but I like the images it produces on the occasions where I can. A 100mm-ish macro lens also has the advantage that it does double duty (ie you gain a good portrait lens, AND the best macro focal length).

If I were buying a dedicated portrait lens, it would likely be the DA70 Limited: having tested 70mm as a focal length (on my DA 50-200) it gives a more comfortable/natural distance than either 50mm or 100mm (I have lenses of both - see signature), it also has a faster aperture (f2.4 vs f2. and faster autofocus (due to no macro) than either of my DFA primes.

{EDIT: This got a bit longer than I planned. If you just want the recommendation feel free to skip it }

As for a landscape lens, I might go left-field and suggest the DA18-55 kit lens. It isn't the fastest not the pixel-peepiest, but the images it can produce (especially stopped down, where a lot of landscape photography takes place) are lovely.

On the assumption that 'use the kit lens' is not a useful recommendation to you, the two main alternatives are the Tamron 17-50 and the Pentax DA 17-70 I mentioned earlier.

The Tamron has f2.8 (compared to f4 on the DA), and is cheaper (by about £120 or so).

The DA 17-70 still has constant aperture which is the real important factor for landscapes (you don't need to change the shutter speed when you zoom in) - it is also likely to be much better built than the Tamron (Tamron's 28-75 and 17-50 have bad reputations for reliability, the 90mm macro an excellent reputation). It also has that extra bit of reach which might be just enough to mean you don't need to take a second lens with you for walkabout - always nice.

The DA*16-50 mentioned above has the capacity to produce some very nice images - it is also weather sealed (the only lens on this list which is) which will be useful for outdoor work if you have a K20D or K7. However the 16-50 has a dark soul: there are reports various failures all of which (autofocus, poor image quality on one side, etc.) seem to be caused by misalignment (ie the lens being built squint). These problems tend to be magnified by internet forums (when was the last time someone posted "I bought a lens a year ago, and nothing has gone wrong. Well done manufacturer!" ?), but it seems a safe bet to say that the DA*16-50 is the least reliable lens (ie most likely to go wrong) in Pentax's current lineup. It's also less sharp wide open at the wide end (ie f2.8 at 16/17mm respectively) than the Tamron is.

Recommendation

Landscape: DA 17-70 f4

Portrait: DA 70mm f2.4

Thank you David found that very interesting reading I have the Sigma 10/20 and 17/70 which I use for landscapes. I also have the Pentax SMC M 50mm 1.7 and the 50mm 1.4 for portraits but have been thinking of adding something a little longer the DA 70mm 2.4 as well as the Tamron 90mm have interested me for a while now. I have also the SMC M 28 AND 35mm lenses which I also use in the feild. If I had to choose just two then I would probably choose the 10/20 Sigma and the 50mm 1.7 Pentax.
Ian

I have had a lot of luck with the DA16-45 for landscapes. Same or better IQ as the DA* but way lighter and cheaper. The FA31 would also be excellent for this application.

For portraits the FA43 and FA77 are not going to be beaten.

I find it hard to pick between two lenses with different focal lengths! They both give outstanding image quality IMO, super-crisp and 3D looking. The Tamron's not a bad macro lens either (I have the old manual 'adaptall' version btw).

Like you I also have my eye on the DA70mm, which looks a superb lens.

Ooooh yes they are.

So says the owner of an FA*85

If I had to pick between 50mm and 90mm, I'd stick with the 50, especially on APS-C.

I'm unconvinced that the Tamron makes a good portrait lens. Slightly too long - esp on crop sensor - and almost too sharp! It's a very fine macro lens, and can be used successfully for non macro shots, but with limitations: not least how long it takes to focus.

You obviously need both!