Originally posted by ubjy Wow what a great thread. Have been lusting after the DA 20-40 Ltdvery recently after buying a KP. Great to hear your experiences. So is the IQ of limited prime repute Sandy/Bruce? Would be ace to see some real world images please.
First up, I don't subscribe at all to the idea that primes offer superior IQ over zooms. There are plenty of zooms that have exceptional IQ. Where (some) primes have advantages over zooms is their wider apertures, they are faster lenses therefore in certain circumstances (low light) can perform better by giving lower noise. Also primes can give better subject isolation and more pronounced depth of field due to faster apertures, but I wouldn't call this superior IQ over zooms. It's a trade off, a prime can't zoom.
I've seen enough images taken with the 24-70, 15-20 to feel as though they are performing just as well as a prime. So I really don't like this 'prime zoom' tag being attached to the 20-40, but I can understand a little of where that attitude has come from.
You can't help compare the HD DA 20-40/2.8-4 with the HD DA 15/4, HD DA 21/3.2 and HD DA 35/2.8 Macro.
I still own the 35 Macro but sold the other two, no regrets. For me f4 is a bit lame for 15mm, same for f3.2 for 21mm (when it's nearest competitor might be considered the FA31 which goes to f1.8). With complete non FF compatibility, no WR and poor star bursts eventually led me to sell them (I vowed to replace the HD DA 15 with just the DA 15 when funds allowed and a good copy found because the DA 15 does star bursts pretty well). I will replace the DA 21 with the FA31 which by all accounts does star bursts pretty well, and of course IQ is incredible, the only draw back is it's quite a bit bigger. In fact that would be the 15 and 21's main strengths, their awesome size. I'm not hating on them, they just weren't for me.
The HD DA 35/2.8 Macro I feel is actually in a league all of it's own. It seemed
significantly sharper than the 15 and 21, wide open it is good to go. Combine that with semi decent FF compatibility (not fully, but you can get decent 30mp crops etc), Macro, stella IQ, HD coating etc, I fully understand why it has such ridiculously good reviews, possibly the greatest walk around lens period (or at least prime wise it has to be up there).
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If the 35 was WR... that would be some treat.
I would actually say the HD DA 35 is probably the best 35 that exists for Pentax to date,
even on the K-1. I would happily sacrifice some edging, or turn those 3:2 shots into 4:3 crops for the IQ and additional versatility it carries over it's competition. On crop sensor I doubt there is a better 35 period (and that includes the new HD FA 35/2).
But anyway... I digress slightly, I now own a HD DA 20-40 along with the 35 Macro... but I intend to sell the 35 Macro. Sounds like I'm contradicting myself, but I'm not. Hear me out.
As good as the 35 Macro is, it's not WR, and this is my primary reason for purchasing the 20-40, I was completely without a WR lens 'till this came along. For macro I prefer using my Velvet 56, it does macro's... differently shall we say, but it suits the kinda macro genre I do (wedding rings), so the HD DA 35/2.8
Macro ability is not something I really need. And now that I have the 20-40 I have the 35mm range acceptably covered along with WR to boot.
But is the 20-40 as sharp as the 35? Maybe not, but I think it's more than capable and sharp
enough. What's most interesting to me is I feel I can use the 20-40 on FF mode and cope with removing the FF vignette easier than what I could with the 35 Macro. In a way I feel the 20-40 is playing ball better with the K-1 than the 35 does. I can even shoot with the hood on the 20-40, or even add a cpl and still am not suffering additional vignette problems, whereas the 35 Macro needs the hood retracted, and forget adding any filter of any kind, you start to lose more real estate.
So far I have only really shot
proper shots with the 20-40
on the K-1 (in full frame mode, not crop mode), so you will have to factor this in when assessing these shots. I have done enough initial testing with the 20-40 on the KP to know it is performing fine. Sitting on the KP the 20-40 gives a FoV equivalent of 30-60mm, I am mostly interested in the 20-28mm compatibility of the 20-40 lens on the K-1 (as it gains additional benefit overall).
You can judge these processed images for yourself, but I am completely sold, it's doing very well on the wrong camera
HD DA 20-40 on K-1 (Full Frame Mode) | Flickr
Please note some of these shots have also been shot using pixelshift, it's best you check the tags to see if it was used or not.