Couple of lens questions

1. I have the 50mm 1.4. It seems really soft at under f2.8, by f4.00 it is sharp. Is this normal? I ask this as this lens was attatched to my K100D that got destroyed when it was soaked. I am now using it on my new K20 and when I zoom in on an image it looks soft (almost blurry) but is fine by the time I go upto f4. Could it have suffered some kind of water damage?

2. I have the 50-200 kit lens and I really enjoy the range of it. I like getting candid portraits at the long end. What would be a good replacement for it to get a better quality lens?

Thanks for any help

I don't have the the 50mm you mention, but yes it certainly sounds like yours has been affected by the dunking. As far as I know this lens is considered a good performer even at 2.8 or under.

Re. the 50-200, the obvious way to go would be to get the DA55-300. I traded up last Xmas and have been very happy with the results. The 55-300 is definitely a step up both in terms of image quality and range. The extra 100mm would certainly be useful for your candids.

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Mhuni

500px

The 55-300mm is regarded as an improvement over the 50-200mm, I think. I guess it depends whether you need the extra range.

Dave

1. don't know for sure but would say yes, the 1.7 are quite a bit sharper it seems but someone else can answer that far better then me.

2. the DA 55-300 is seen here as best in his range.
You also have the Tamron & Sigma 70-300.
Tamron is sharp but has CA problems,
Sigma doesn't have those problems but isn't really sharp at the long end,
Pentax is the best compromise between these.

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Stefan


K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ

I never considered the 55-300. Because it had a longer range, I thought it would be an inferior lens!!

The 55-300mm is a good lens but personally I would look for an older MKI Sigma 70-200mm f2.8 on Ebay if you want better quality (I noticed one on there yesterday actually). The MKI is an excellent lens and will also take the matched 1.4x Sigma teleconverter with very little IQ loss.

Of course if you want something really good then I think Amins DA* 60-250mm is still available in the classified section.

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. My Flickr

50 F1.4 is very soft wide open with low contrast. Its far more noticeable on a camera like the K20 at 100% (14M) than the K100 (6M).

Not unusual for lenses in this class. See here....

http://www.photozone.de/pentax/126-pentax-smc-fa-50mm-f14-review--lab-test-repor...

The 55-300 is a nice lens but not a major step up in IQ or speed terms (and its performance tails off a bit beyond 240mm). If you want a major improvement then you need to look at the 60-250 F4 which is a stunning lens.

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Cheers, Steve

Also, the extra range at the lower end is something you don't get with the 70-300/70-200 options

Being softish wide-open is one of the things that contributes to making Pentax 50mm lenses good for portrait on DSLRs.

But you don't know what soft is until you've seen the 50 1:1.2 wide-open!

G

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Keywords: Charming, polite, and generally agreeable.

While I'm sure the DA60-250 & Sigma 70-200 would represent a significant step up, you should bear in mind not only the extra cost (they are significantly more expensive) but also the greater ease of use of the 55-300, which, if I'm not mistaken, is as much as 1kg lighter than these lenses. Also, 55-300 is a really practical range. Meanwhile, re. quality beyond 240mm, I've found the 55-300 to be pretty good even at 300. For an example of a shot at 300, see this: link.

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Mhuni

500px

Having both a 55-300 and a 50-200 I wouldn't say the -300 is significantly better IQ wise. It may be that we have a really good copy of the 50-200 but side by tests when we got the -300 to check it out didn't show it as noticably better or noticeably worse.

The 70-200 / 60-250 are what I would look at if I had the money, but if not by all means get the -300 but for it's extended range rather than expecting a 'class up' in quality.

In my experience, in everyday use (not tests) I'd definitely say the 55-300 is a sharper and contrastier lens than the 50-200. I think a lot of other forum members would say the same. It is a step up IMHO. I also really like the extra 100mm.

I couldn't have taken the shot in the link above (handheld, by the way) with my 50-200, both because of length and it wouldn't have been that sharp.

Regarding the more expensive faster telephotos - no doubt these would be more of a step, but then that depends on whether nigelp wants to fork out the extra dosh and is happy with the bulk of the 60-250 or 70-200. I'd say the size of the 55-300 makes it a more practical lens for candid photography. But up to now I've avoided bulky lenses, so I'm not really in a position to comment on how viable these are. But I have been very happy with my 55-300.

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Mhuni

500px

1. The 50mm F1.4 is a little soft wide open, but keep in mind focus is also very critical at such wide apertures. My 50mm 1.4 is soft wide open (though still nice for portraits), acceptably sharp by F2.4 and by F4 you could cut yourself on it. If you would like me to take some test shots to help you determine if yours is performing normally, I would be happy to do so (though it might take a day or two).

2. The 55-300 is the obvious choice, it's a better lens in all optical respects than the 50-200. It is larger though which might limit its usefulness for candids. The lovely thing about the 50-200 is no one realises how long it is until they see the photos, as it basically looks like a standard short zoom.

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