[timb64]

2x is what a lot of the best lenses have. DFA 15-30, DA*11-18, Sigma 18-35 f1.8 ...

Yes,but as you're well aware each extra mm at the wider end has a far greater effect on field of view.My personal view is that it's just a bit of a niche range that a lot of users can cover by shuffling a little bit one way or another with their favourite prime (and I never thought I'd advocate zooming with your feet!!)

[c.a.m]

To my mind the 20-40 just seems a very strange and narrow range for a zoom.

One might think so, although it does provide a useful range of focal lengths that would otherwise require, say, a set of 21/35/40mm Limited primes.

I find the 20-40 to be quite versatile, even though it doesn't cover the usual 17/18-50mm span.

- Craig

[monochrome]

My standard lenses on KP are 21, 40 and 70. I can shoot almost anything with those three and foot zooming. I have nothing but good things to say about all three, especially the 21 and 70.

I also have the 20-40 and love/hate it. There’s minimal IQ advantage/disadvantage with the zoom and I feel like $400 is sitting on my shelf for nothing. OTOH when it is on the camera for interiors and exteriors (snapshots mostly) the convenience overcomes any loss of IQ and variable aperture. I’m always happy I have it for those uses.

ATM there seems to be little second hand demand, so take that into account.

[baba_yaga]

My experience with both lenses is similar to most of those already posted. I have to second the comments of NZ_Ross, the 21mm non-HD version produces fantastic starbursts on rippled water. If this is your cup of tea, I have not encountered another DA lens with similar characteristics. As others pointed out, it is great, very compact walk around lens in crowded streets, markets, etc. On the minus side, in addition to the lack of weather/dust proofing, the maximum aperture is a bit limiting in darker locations, e.g. indoor bazaars, bars, especially when photographing moving subjects. This is less of a problem on the most modern bodies but on my K5IIs one fairly quickly runs into the high ISO/high noise regime,
The 20-40 is an entirely different animal, although it is still remarkably light and compact, nearly as inconspicuous as the 21. Even though it is a zoom, in pure optical terms it is hands down superior to the 21mm. In some situations it may lack the magic of the 21, but it is very sharp and contrasty - a more modern lens, no doubt. The fast, nearly silent focusing is well above the Pentax average.

[Wheatfield]

I have wanted the DA 21 (either version) for quite a while, but also like the DA 20-40. The 20-40 has the advantage of being weather sealed, which means a lot, but the 21 is of course a prime. The only Limited that I have now is the 15, which is one of my favorites. Since getting the 15 about five years ago, my Tamron 10-24 doesn't get much use. I would look for similar performance from the 21 and the 20-40.

Which comes to the question, if you have or have had both the 21 and 20-40, are they redundant? Is it worth it to have both, how do they compare? Obviously the 20-40 is sealed and covers a range of focal lengths, but is the 21 so much better, or maybe it's not better. I've read a lot of the reviews and looked at samples, but I'd like to hear what those who have used both say. Thanks in advance for your replies!

I had both. The 20-40 is the better lens based on my usage, but I found it to be a bit clumsy. I called it the best lens I've ever owned that i didn't like.

[BigMackCam]

I have both lenses - the HD DA21 and the HD DA20-40...

I feel like a scratched record for saying this yet again, but... try as I have, I just can't fall in love with the DA20-40

Of course, it has a lot going for it... the focal lengths of three DA Limited primes (and everything in between) with good close-focusing capability, near-silent DC motor AF and a WR body that's beautifully built and presented. At the wide end, it's a tad faster than the DA21 (f/2.8 vs f/3.2) and the distortion - whilst slightly worse - isn't bad and is easily corrected. Out of focus highlights aren't as silky smooth and uniform as with the DA21, but decent nonetheless, and out-of-focus rendering is generally very nice. Centre sharpness is really good throughout the focal length range, with borders becoming decent around f/5.6.

BUT... at the longer end, it has runway style field curvature that is most noticeable when focusing at distance and with something in the borders at closer range, and it's there even when stopped down. I don't believe I've encountered this behaviour with any other lens. Focus with the centre AF point at something in the distance, and anything close to you at the sides of the frame will be disconcertingly in focus. For a lot of shooting, it's not an issue... But it can matter for certain landscape, city / architectural and other types of photography where a flatter field would be preferable. And once I noticed it the first couple of times, I just couldn't "un-notice" it.

I'll say again, though - the DA20-40 has a lot going for it. And I've made a real effort in recent weeks and months to use it more, to the point where I'm at least enjoying and getting some value from it. I've no intention of selling it, because it's certainly versatile, and the WR is very useful. But it's far from being my favourite lens.

The DA21, on the other hand, is - or, rather, it's one of my favourites. And I can't quite put my finger on why, because it's not a stunning performer on paper. It's not especially fast. Centre performance is very good, but the borders are just OK unless it's stopped down (although they're better than the DA20-40). But I love the rendering. It has a character that is subtly but noticeably different from any other modern lens I own that covers this focal length, almost like a modern incarnation of an old film-era lens (maybe that's why I like it, as there are so many vintage lenses I really like). Plus, it's compact and cute, and nice to use

For me the big question is always what would I want to do. If you are thinking of buying a 20-40 and end up with a 35Ltd, then it is clear to me that one did not have a real purpose for acquiring a 20-40. I own one and it depends on what I am about to take pictures of. It also depends on the camera I am going to use. I own a 16-85 as well, but if I want to take pictures with my K-01 I choose either a prime (40Ltd or 55*) or this 20-40. The 16-85 is to heavy for comfortable use with the K-01 imho. I a3lso own a K3II bought in a kit with 16-85 and quite often this lens is on the K3II, but also a Sigma 17-50. So maybe the 21 gives better pictures, but if I am in a place where it is bit difficult to move backward an forward I would go for the 20-40 because it is a zoom and I can adjust the composition standing still instead of moving back- and forwards. As for "To my mind the 20-40 just seems a very strange and narrow range for a zoom." just get that lens on your camera and experience it instead of thinking that it might be a very sstrange and narrow range for a zoom. It is not!

[aslyfox]

to quote an old ad:

" sometimes you feel like a [ prime ], some times you don't "

You Tube

You Tube

so find good " experienced " copies and get both

[ramseybuckeye]

so find good " experienced " copies and get both

Interestingly, there are very few 20-40 copies available, and most are priced higher than new,

[ThorSanchez]

I just returned from a European vacation where I had my 15/21/40 limiteds, took the 55-300PLM for reach, and rented the 20-40 for bad weather. I have many hundreds of RAW files to still go through, but I don't know that the 20-40 really clicked for me. It was fine. The weather-sealing was indispensable, it rained several days, sometimes pretty hard. But I'll have to specifically sort by lens to tell which photos were from the primes, and which were from the 20-40. Nothing popped, nothing said "wow, this is something else." Build quality was great, the lens looks great, but it's bigger than the primes, and the focusing (while silent) wasn't any faster than the screw-drive primes. At least I didn't think so.

I rented the 20-40 because I was curious, and I wanted something WR and better quality than the 18-55 kit lens. I'm sure it was better than the kit, but I don't know if it's worth spending $400-500 on a copy for myself. I think I liked the 16-85 I rented for a trip to Iceland last year better, even if it is bigger and not a limited.

[lesmore49]

I just have the 21 Limited. I find it an excellent lens and if I'm travelling very light and pressed for space, it takes up almost no space to tuck it into a small bag.Excellent quality and tiny..those are it's two 'prime' advantages for me.

[ThorSanchez]

I just have the 21 Limited. I find it an excellent lens and if I'm travelling very light and pressed for space, it takes up almost no space to tuck it into a small bag.Excellent quality and tiny..those are it's two 'prime' advantages for me.

If it were WR I think it would stay glued on a lot of cameras.

But would also eat into sales of the more expensive and possibly more profitable 20-40...

[aslyfox]

Interestingly, there are very few 20-40 copies available, and most are priced higher than new,

hope springs eternal

if I recall correctly there was one or two recently in the market place that went for a very low price

[mikesbike]

For me the big question is always what would I want to do. If you are thinking of buying a 20-40 and end up with a 35Ltd, then it is clear to me that one did not have a real purpose for acquiring a 20-40. I own one and it depends on what I am about to take pictures of. It also depends on the camera I am going to use. I own a 16-85 as well, but if I want to take pictures with my K-01 I choose either a prime (40Ltd or 55*) or this 20-40. The 16-85 is to heavy for comfortable use with the K-01 imho. I a3lso own a K3II bought in a kit with 16-85 and quite often this lens is on the K3II, but also a Sigma 17-50. So maybe the 21 gives better pictures, but if I am in a place where it is bit difficult to move backward an forward I would go for the 20-40 because it is a zoom and I can adjust the composition standing still instead of moving back- and forwards. As for "To my mind the 20-40 just seems a very strange and narrow range for a zoom." just get that lens on your camera and experience it instead of thinking that it might be a very sstrange and narrow range for a zoom. It is not!

I have both, the DA 21mm LTD since around 2011, and my experience is similar to the above^. I acquired the DA 20-40mm in 2016 when a great deal on a new one popped up. The reason for the "strange and narrow" zoom, which is more useful than strange, is to keep the lens remarkably compact for a zoom lens having both WA and some tele capacity for versatility, while at the same time providing exceptional aperture speed at the short end for a compact zoom lens. Of course it is comparably large when considered against the DA 21mm, as is any zoom lens except the DA 18-50mm DC RE, which is a slower kit lens and not in the same build class. If needing a high-quality extra-compact versatile prime lens, the 21mm LTD is the one to reach for.

When I need maximum versatility in very good zoom lens on any of my camera bodies, it is my DA 18-135mm WR lens, but more when using say my larger K-5 IIs. With my KP, most often it is the 20-40mm LTD. When getting out and around with a need for range, quality, yet compact carrying, the DA 15, 20-40, and 70mm LTDs is a hard-to-beat trio. If needing more zoom range, instead of the 70mm prime it could be greatly extended with the HD DA 55-300 WR tele zoom while keeping carrying weight reasonable for having such range. It would also be WR for all but the 15mm shots.

If needing more speed for low light or fast action, and an exceptional lack of field curvature for a zoom lens, it is my also often-used Sigma 17-50mm f/2.8 EX DC. But of course those advantages come with more bulk and weight.

As to a choice between the extra-compact 21mm and the very compact 20-40mm LTDs, both are versatile, but the 20-40mm is more so and provides WR.

[Photobill]

To my mind the 20-40 just seems a very strange and narrow range for a zoom.

Yes it does. But if you think of it as a 21mm, 35mm or 40mm Prime that allows you a little bit of wiggle, it helps you get your head around it 👦f