[MSD]

I know it could be by this title another "what lens should I buy" sequence.
Frankly, I know the glass that's out there and I just would like to hear some opinions from people who actually own that glass.
So here's the situation: I have a K20D, Sigma 18-200 and recently bought a Super Tak 50/1.4.
I am going for the first time out of Australia/USA in my life in about 2.5 weeks, on a 1 week trip to New Zealand, and I feel that I would like to get a new lens in that time.
Of course much emphasis will be on landscape ( I would rather shoot than ski but I'll do a mixture), and I already know I love small primes (as some of you may know by now), confirmed by my recent 50/1.4 purchase.
So back to lens specifics: I would rather any 2-prime combo to my zoom, which I am not particularly fond of, and the 50mm could be one of these. I also know that it seems there are two (to generalise) types of landscape: wide and non-wide. Particularly, in the way of Pentax lenses, it seems these groups are well represented by the 15/21 on one end and the 70/100 on the other.
It is possible (but not certain) that I could get my hands on a K30/2.8 before the trip, but I would not rely on that possibility to make a decision.
So, after yet another pentaxforums.com block of text, I get to the point: I would like to hear advice regarding the use of Pentax primes in landscape-specific conditions, for the lenses aforementioned or any others that people deem appropriate.

To stop this reeling off into a DAvsFAvsZoom etc thread, as I have much of this knowledge readily available on the site already, I ask that we keep the discussion I hope will ensue to a purely travel/landscape/purchaseable in 2 weeks concept. I will be pleased to hear people's personal experiences with their own selection of lenses, and any advice for me.

Alright, after that I'm feeling a bit selfish in that I ask purely for my own benefit... Let's call it a discussion on lanscape-appropriate lenses for all.
Thanks everyone.

[Chaos_Realm]

I think that you would be happy/covered by any of your prime's you listed. all are fantastic lenses. Maybe the 70 over the 100 and 21 over 15 for travel to keep them a bit smaller and compact.

[pxpaulx]

I would run a check (there is a free program for this, can't remember it off the top of my head) against your current photos to see where you take most pictures with the sigma zoom. If that shows you are constantly butting upto the 18mm wide end, then get the 15mm - it is spectacular, and a great wide landscape lens. If you shoot somewhere in the 20-30mm range the 21mm (or perhaps an older 28mm) lens might be a better choice.

[TOUGEFC]

Exposure Plot is the software that checks all you data and you can veiw your most used focal lenght aperture etc... in graphs-
ExposurePlot (former Focalplot)

My advice would be the DA15 or DA21 for a wide prime, to pair up to your 50. And if budget allows grab the new affordable DA-L 35mm f/2.4 to fill the gap between the DA15 and your 50

[reeftool]

Exposure Plot is the software that checks all you data and you can veiw your most used focal lenght aperture etc... in graphs-
ExposurePlot (former Focalplot)

My advice would be the DA15 or DA21 for a wide prime, to pair up to your 50. And if budget allows grab the new affordable DA-L 35mm f/2.4 to fill the gap between the DA15 and your 50

I agree. You mention you prefer small primes. Go with the best. I have the DA 15 and I'm liking that lens more and more as I've had it for a couple of months now. I'll be adding the 21 down the road but for now I'll crop the occasional DA 15 shot if I need to. I do a lot of car/motorcycle events and the 15 is much better for my needs and it does an excellent job with landscapes also. If you don't need the wider shots then get the 21.

[MSD]

I just did an exposure plot of my material from the last few months. In digital equivalents, in the 18-100 (small prime) range, the standouts were:
18mm- 340+ uses
45-55mm- 360
100mm- 210
30mm- 160

The 45-55 height is probably due to 50mm being my only prime.
There were significant lows (very few uses) between 18 and 30mm, and lower usage between the other FL's mentioned.

The 15mm seems like a great option, but I do hear that the 21 FL is more generally useful and easier for composition.
I think I would do well with a 15-30 pair (if I can get the K30 after all my time hunting!). A 43-50-55 somewhere in there I think would also work well.
Is 30-50mm too short for the longer end of a travel kit?

[pxpaulx]

If you're bumping up against 18mm that much, you'll definitely enjoy the 15mm more than the 21mm. The 21mm is approaching a normal field of view, and I would be hard pressed to call it a wide angle. It is not difficult to compose at all, it does take some getting use to but it is nowhere the extreme wide that something like the sigma 10-20 or 8-16 are.

Pairing the 15mm with the K30 you've referenced would be a great option. My ideal prime kit is the 15mm, 100mm macro and either sigma 30mm or the 43mm in the middle - a 3 lens kit with the 15mm, K30 and 50mm would work well for many situations too!

[Nuff]

If you are going to Queenstown (the only part of NZ I've been to). I would get the 15mm, the dramatic mountains/landscape will look great with that lens.

[m42man]

Ski-trip to NZ - sounds very nice, I'm jealous! A couple of things occur to me though:

1. With a lot of snow in the frame, the camera will tend to expose for the snow, which will render it looking a bit grey on the photo, i.e. you'll be under-exposed. Make sure you avoid this by using exposure compensation, for example.

2. Going from a sub-zero environment to a warm indoors will result in great potential for condensation. Perhaps best to wrap your equipment in a plastic bag until temperatures harmonise, but at least make sure you don't fiddle with focus or zoom rings - or, worse, change lenses.

Have a great trip!

[MSD]

Thanks for the advice. I'm pretty well decided on the 15/4, maybe even only for size and FL which win me over.
My questions for the trip continue however:
- I am realising I need filters. Polarizing and 2-stop GND seem to be the ones I would want, but on B&H at 49mm these are $40 each. I think they are worth it but I would like to hear some opinions, especially with regard to a ski trip.
- Tripod: I won't have opportunity to take a real one, but is it worth it taking a little one for landscapes? I know it depends on style, but I think long-exposures can be great for landscapes.
- Protection: Thanks to m42man for the advice. I am wondering about how people take their lightweight kit physically up the slopes with them... Some kind of mini-tight backpack?

Thanks for the help. I look forward to getting the 15 and going!