[DanielT74]

I had the Sigma 30/1.4 and sold it to replace it with the 31ltd which I don't find so much better actually. At least not proportionate to the price. Maybe mine isn't such a good copy? Not sure.

[vtqanh]

Bull. If you don't want the lens then don't buy it but don't post falsehoods like this when you have no experience with the lens.

If you re-read my post, I actually mentioned that the AF issue is what "I've heard" from reading around the reviews. Does everybody have to experience with the lens to actually voice his/her opinion about it? I don't think so

To me Pentax's focusing system is already ways slower compared to a few other systems, and thus I try to stay away from lens with poor AF performance.

[JeffJS]

If you re-read my post, I actually mentioned that the AF issue is what "I've heard" from reading around the reviews. 1. Does everybody have to experience with the lens to actually voice his/her opinion about it? I don't think so

2. To me Pentax's focusing system is already ways slower compared to a few other systems, and thus I try to stay away from lens with poor AF performance.

1. I Read your post. Yes. Because unless you have actual experience, your opinion means NOTHING.

2. Then buy a faster system.

_

[Smeggypants]

If you re-read my post, I actually mentioned that the AF issue is what "I've heard" from reading around the reviews. Does everybody have to experience with the lens to actually voice his/her opinion about it?

Of course you do!!!

How the f**k can you have a credible opinion about something if you've never used it.

JeffjS is correct you opinion is worth NOTHING.

it really annoys me when people just repeat stuff parrot fashion.

[zxaar]

Of course you do!!!

How the f**k can you have a credible opinion about something if you've never used it.

JeffjS is correct you opinion is worth NOTHING.

it really annoys me when people just repeat stuff parrot fashion.

How someone can have a credible opinion if he has never used it???

Really you believe in it.

I can give you many examples when someone has a credible opinion when he has never used it. For example I have an opinion about space and universe. I have never used spacecraft nor i have used anything related to hubble telescope. Based on what I have read from NASA i have very good opinion.

There are many other examples i can give you when someone can have credible opinion based on what he has read and not used it first hand.


As far as pentax's AF is concerned I can say from first hand experience that I found k100d AF slow to the point that I preferred manual focus then AF.

K-x, k-7 are very much improved and i would not call them sluggish. They infact very good and usuable. (this is also first hand experience).

What i have read about k-5 is , it seems it has very good AF and since I have never held k-5 you can call it bull sh*t and dismiss it as wrong. It is upto the reader. (incredible opinion :-D ).

[JeffJS]

How someone can have a credible opinion if he has never used it???

Really you believe in it.

I can give you many examples when someone has a credible opinion when he has never used it. For example I have an opinion about space and universe. I have never used spacecraft nor i have used anything related to hubble telescope. Based on what I have read from NASA i have very good opinion.

There are many other examples i can give you when someone can have credible opinion based on what he has read and not used it first hand.

This too is a load. You can give an opinion about the Hubble Telescope because you can see samples from it. FWIW, when they first launched that thing, It too was screwed up. Remember?

Still though, until you've mounted a lens, on a specific camera, and actually used it, the opinions are worth excrement (choose the animal).

[zxaar]

This too is a load. You can give an opinion about the Hubble Telescope because you can see samples from it. FWIW, when they first launched that thing, It too was screwed up. Remember?

Still though, until you've mounted a lens, on a specific camera, and actually used it, the opinions are worth excrement (choose the animal).

still haven't used hubble yourself, isn't it. Which was your prime criteria to form valid opinion.

Still though, until you've mounted a lens, on a specific camera, and actually used it, the opinions are worth excrement (choose the animal).

i think you should talk about yourself that other than the gear you own your opinion does not worth a dime (with your criteria) . I do not subscribe to this notion.

[JeffJS]

still haven't used hubble yourself, isn't it. Which was your prime criteria to form valid opinion.



i think you should talk about yourself that other than the gear you own your opinion does not worth a dime (with your criteria) . I do not subscribe to this notion.

As it happens, I Do own the DA*55. What I meant by my Hubble comment is your opinion is valid based on images you have seen from it. If you (or anyone else) simply stated that you don't like the Images from the DA*55, and for that reason you wouldn't buy one, or it is too expensive, or something like that, I could respect and understand that. But, to parrot information you read on the net about Autofocus of the lens without ever using one, is still bullshit, no matter how you sniff it. I really don't care if you 'subscribe' to it or not.

[Pablom]

I'll chim in with Jeff here. Sorry guys, if you based your opinion on a lens' performance, that one could only obtain first hand (such as AF), on what you heard or read than it is invalid, at least without a proper citation, and just makes a big mess out of these forums for someone looking for real feedback.
Really, that sort of attitude should be reserved to the rumors section.

Peace

[Ash]

We're starting to go a little wayward here. Stick to facts and *helpful* opinions guys. Any doubts about the 55? Then try it... on a K-5, then come back and report on its AF performance. And then move on...

[axl]

Interesting debate (if we skip the credible opinion part)...

As owner of 31-43 and K50/1.2 and former owner of DA*55 and F50/1.7:
1 - I'd never say 43 is better in anything else than center sharpness than 31 (especially when compared to 50/1.2). 31 has OOF rendering very similar to that of 50/1.2 (closest from shorter focal lengths I've tried)
2 - I wouldn't say 31 is soft wide open. My copy is acceptable, and really sharp when shot at closer distances, going towards infinity it softens up a bit IMHO, but then I don't shoot 31 @1.8 @ infinity too often...
3 - DA*55 is slow to focus (on K10D) but not much slower (if at all) than 43ltd and still faster and (most of the time) more accurate than MF + you have constant MF override if you need it
4 - DA*55 is sharper than 50/1.2 (my copies) wide open
5 - 50/1.2 blows 55 out of water wide open in OOF rendering (but then I think the same when 50/1.2 vs 43 are compared, if you like 43's OOF you would like 55's IMO)
6 - DA*55 is a beast when compared to any other 50/55 (with possible exception of Canon 50/1.2)
7 - F50/1.7 is the fastest AFing lens I tried in K system to date, and very accurate at that
8 - F50/1.7 (and I expect it's cousin FA50/1.7) is very sharp right from f1.7 but stopped down the hexagonal OOF gets annoying (personal opinion, you may like it)
9 - OOF of 50/1.7 when stopped down below anything than f1.7 is not as good as 50/1.2 at any aperture

my 2p

---edit---

if you'll buy anything to replace that A50/1.2 of yours, please let me know. I'd be more than interested to replace my K50/1.2 with it's A series cousin.... thanks

[Clinton]

The DA-55 has terrible AF performance, that's what I heard. There's no point spending that much money for an AF lens that you can't count on its AF!

I'm not sure where you heard this.

I find the 55/1.4 to be a fantastic performer, and I use it more commonly than the 1.2 because it's AF is smooth. If course, if you're tying to AF in a dark room with the lights turned out and no AF assist light.... well, good luck focusing the 1.2 by hand.

Now if you're capturing sports action, well it's AF might not be fast enough, but that leads to the question, why would you try to capture sports action with the 55/1.4?

Your alternative really is to buy the Sigma 50/1.4 and live with the onion bokeh, or the Sigma 30/1.4 and live with the edge softness.

[Pentaxor]

I'm not sure where you heard this.

I find the 55/1.4 to be a fantastic performer, and I use it more commonly than the 1.2 because it's AF is smooth. If course, if you're tying to AF in a dark room with the lights turned out and no AF assist light.... well, good luck focusing the 1.2 by hand.

Now if you're capturing sports action, well it's AF might not be fast enough, but that leads to the question, why would you try to capture sports action with the 55/1.4?

Your alternative really is to buy the Sigma 50/1.4 and live with the onion bokeh, or the Sigma 30/1.4 and live with the edge softness.

Yes, this is a better description of the DA*55's AF speed. I think the OP is just misinformed or misused the word terrible. however, it is terrible for any constantly fast moving action and sports photography. SDM is not faster than screwdrive (whether people/owners like it or not). SDM is silent and won't notice it AF. AF is useful and still a comfort of use for certain occasions that doesn't require utmost speed. if I were to say it in a more definite term, the AF is average good.

the lens is very sharp indeed and stopping down at f2.8, cuts like a razor.

[dgaies]

Yes, this is a better description of the DA*55's AF speed. I think the OP is just misinformed or misused the word terrible. however, it is terrible for any constantly fast moving action and sports photography. SDM is not faster than screwdrive (whether people/owners like it or not). SDM is silent and won't notice it AF. AF is useful and still a comfort of use for certain occasions that doesn't require utmost speed. if I were to say it in a more definite term, the AF is average good.

the lens is very sharp indeed and stopping down at f2.8, cuts like a razor.

Agreed. The DA*55 doesn't have the quickest AF, but as I mentioned in aprevious post it seems quite accurate and is obviously nice and quiet. Is it a great choice for fast moving action/sports, no. If it faster than my screw-driven lenses, no (with the exception of the DA35). Is it faster than my trying to focus my A50/1.2, yes.

Perhaps part of the issue is that because of the high cost of the DA*55, in comparison to of AF of the competition, the AF of the DA*55 is a bit underwhelming.

[paperbag846]

I think the AF of the 55* was designed to be unobtrusive for portraiture, wedding photography, etc. Times where the action is slow, but it is advantageous for your camera system to be quiet as possible for comfortable subject? Besides, I think stating "AF is poor" is a completely subjective observation that is really hard to measure.

AF is one of those things that could ALWAYS be better, and it is misleading to talk about some sort of AF standard that all lenses must live up to.

Anyways there is not too much to pick from in this range, since most of pentax's 50's have shared the same optical formula for a long time. I would have thought that the FA 43 wold be what you would want for the f2 performance. I'm going to guess (from only having looked at sample photos) that the DA* 55 would be your next best bet, as the stopped-down bokeh is still very smooth and circular. I also prefer the 55mm FL over the 50mm FL for portraiture and intimate candids (of course, I'm using very cheap alternatives to the 50 1.4 and th 55 1.4, so take my opinion for what it is worth... very little ).