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02-24-2009, 08:05 PM   #226
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QuoteOriginally posted by Buddha Jones Quote
Why is fast AF speed needed for a portrait lens?
Because our photography business takes candid portrait pictures of children and families (on the move and on locale). The FA50 is a great lens - albeit slow, but bearable. I was hoping that the DA55 would be at least as fast, or a bit faster.

Going with a lens that is slower than the FA50 isn't going to be an option for us.

c[_]

02-24-2009, 08:40 PM   #227
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QuoteOriginally posted by Buddha Jones Quote
Why is fast AF speed needed for a portrait lens?
--I'll speak here for my own needs and experience.. not to try to tell anyone how they should feel.... just my own opinion, but here it is--

If you are going to AF at all, then yes, fast AF is important!!!. There's just way, way, too many really good manually focusing lenses out there that do a far better job with bokeh, detail, contrast, you name it.

If you are doing a sitting, a headshot or the like, then no, you don't need fast AF, in fact you don't need AF at all, then you can choose a lens that is MF.

But if you are doing a dynamic shoot like a fashion or glamour shoot, one that actually does require AF, then using a lens with slow AF kinda defeats that purpose (for me, anyway)
02-24-2009, 08:46 PM   #228
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Very good point! I agree 100%.
02-24-2009, 09:56 PM   #229
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QuoteOriginally posted by David Whiteley Quote

FWIW, isn't AF speed linked to throw of focus ring? So wouldn't it be natural that they'd build the DA*55 with a long throw for finely-tuned focus, but also produce slow AF in the process? Not that I understand such things...
Yep, both my old FA-J 18-35mm and the DA 17-70 SDM had super-short throws; and focused very fast, even as f/4+ lenses.

02-25-2009, 07:55 PM   #230
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QuoteOriginally posted by augustmoon Quote
--I'll speak here for my own needs and experience.. not to try to tell anyone how they should feel.... just my own opinion, but here it is--

If you are going to AF at all, then yes, fast AF is important!!!. There's just way, way, too many really good manually focusing lenses out there that do a far better job with bokeh, detail, contrast, you name it.

If you are doing a sitting, a headshot or the like, then no, you don't need fast AF, in fact you don't need AF at all, then you can choose a lens that is MF.

But if you are doing a dynamic shoot like a fashion or glamour shoot, one that actually does require AF, then using a lens with slow AF kinda defeats that purpose (for me, anyway)
QuoteOriginally posted by ll_coffee_lP Quote
Because our photography business takes candid portrait pictures of children and families (on the move and on locale). The FA50 is a great lens - albeit slow, but bearable. I was hoping that the DA55 would be at least as fast, or a bit faster.

Going with a lens that is slower than the FA50 isn't going to be an option for us.

c[_]
Gotcha, I don't shoot people (yet) so I wasnt quite sure. My idea of a portrait is,"sit here and don't move"
02-25-2009, 08:11 PM   #231
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Wedding, event photography or spontaneous portraits do really benefit from accurate and fast autofocus.

Da* 55mm f1.4 was originally a lens I reserve for street candid photography. But that dream is dashed. I will continue using my beloved manual focus lenses instead: Slow focusing is not much good with experienced manual focusing
02-26-2009, 09:38 AM   #232
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QuoteOriginally posted by Buddha Jones Quote
Gotcha, I don't shoot people (yet) so I wasnt quite sure. My idea of a portrait is,"sit here and don't move"
I can relate to that. My idea is "sit there and don't move while I go take pictures of something else"
02-26-2009, 09:57 AM   #233
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New pics with the bad boy DA*55 :

f1.4


f1.4


f1.6


f2.0




Rainer

02-26-2009, 10:06 AM   #234
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QuoteOriginally posted by TKH Quote
New pics with the bad boy DA*55 :

Rainer

I gotta say... the freaking 3D effects on the last two photos, or actually on all these shots are INCREDIBLE!!!

The last picture is freaking AWESOME!!!


This WILL be a VERY contraversial lens.. and despite AF speed, it seems like a IQ winner...
02-26-2009, 10:15 AM   #235
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QuoteOriginally posted by BBear Quote
I gotta say... the freaking 3D effects on the last two photos, or actually on all these shots are INCREDIBLE!!!

The last picture is freaking AWESOME!!!


This WILL be a VERY contraversial lens.. and despite AF speed, it seems like a IQ winner...

This is what I've been saying, hold off judgement until we can get a steady flow
of images in here.

I think it's a pretty compelling package, myself...

(And those last two images look very.... FA 85 1.4-like. Nice. And right where we'd suspected it would land IQ-wise.)


.
02-27-2009, 04:01 PM   #236
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And please dont forget: DA*55 is ****ing slow. For example you cant go for sports.











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02-27-2009, 05:15 PM   #237
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Hmm, as expected, the lens seems to deliver nicely for portraits :-)



I need to do a focus adjustment before I can post anything at 1.4. I love this lens, though!
02-27-2009, 11:01 PM   #238
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QuoteOriginally posted by blende8 Quote
I tested it on the K10D and K20D.
The DA55 is slower than the DA16-50 even.

I have it only one day now, so I couldn't make my mind up really.
But so far it is a little disappointing.
Compared to the FA50 it is really slow.
I see difficulties for low light snap shots.

I don't want to judge the AF accuracy by now.
On the K10D it appears to be so-so.
On the K20D a little better.

I will do more tests with daylight tomorrow.

The focus throw is about twice that of the DA16-50, but a little less than that of the FA50.

One man from Penta-club (Russia) tested DA*55 - yes, it is slower than FA50, but not 3 times slower. A bit. But AF is very silent and smooth.

Last edited by ogl; 02-28-2009 at 03:23 AM.
03-01-2009, 11:40 AM   #239
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I think everyone can actually do a realistic practice test in a quite simple way.

Set up two books in a half meter own distance into two meters distance from the camera. AF-C. Now one can swivel comfortably the camera between the two goals. If one activate the acoustic camera signal, target acquisition sounds clear from the K20D. A second person stops (for example) 15 seconds and one takes in account the camera tones. For me not the absolute number is crucial (hangs also of the speed of your own moving and the lateral distance of both goals) separates the comparison of the two numbers of SDM and Non-SDM. I did this today with me speedy FA135 and the lame sprag DA*55. Before testing two things were clear for me:

1. The DA*55 needs substantially longer time to run the complete range from close to infinite. The FA135 rushes like a rocket by the same. From that results clearly logically secondly:

2. The DA*55 can have as expected no chance against the focus rocket FA135! Whereupon I bet my house for!

Now from theory to practice.

In my experimental setup both lenses created the following focusings with acoustic camera message in 15 seconds:

FA135: 14
DA*55: 15

I three times repetited the test because I to didn’t believed the results! This is for me a large surprise. I would have expected a relationship of 2:1 for one of the speediest Pantax FA lenses the FA135 2.8 (thus so in approximately 15: 8). For me this amazing practical experience relates my initial surprise over the cosy AF through behavior of the DA*55 much. This facts plus the hope for newer and better cameras (like the KM/K2000 shows) make me smile for the future of Pentax.

Dont believe scientists to mutch. You are the king of your camera bag and the lenses must work for your practice quick and acurate.
Best,
Rainer
03-01-2009, 11:59 AM   #240
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QuoteOriginally posted by TKH Quote
New pics with the bad boy DA*55 :

f1.4




Rainer
Did you add any black level? Its 3d effect is crazy.
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