Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-24-2009, 07:18 AM   #76
Veteran Member




Join Date: Mar 2008
Location: CT / NY
Photos: Gallery
Posts: 822
QuoteOriginally posted by lol101 Quote
Anyone else getting tired of hearing this kind of justification?
Actually you sounded really convincing!! It made sense as I was reading your sarcastic inputs.




02-24-2009, 07:42 AM   #77
Pentaxian
gazonk's Avatar

Join Date: Feb 2009
Location: Oslo area, Norway
Photos: Gallery | Albums
Posts: 3,512
QuoteOriginally posted by TKH Quote
And here we have the well known Canon 50mm 1.4. Look on the left corner and you see purple water:
My DA70 shows similar behaviour @ 2.4, if stressed enough, here very reflective hoarfrost:
02-24-2009, 09:13 AM   #78
Veteran Member




Join Date: Aug 2008
Location: California
Posts: 851
QuoteOriginally posted by lol101 Quote
Why the 4000$ Canon gear if you prefer your Pentax?
1. AI Servo
2. 10fps
3. huge buffer (47 raw files)

You seem fairly convinced the speed at which the focus wheel turns is a problem while I am not convinced. I conducted a test using 50-135 and cars traveling at 30mph. taking pictures at 3fps the front of the car was ALWAYS out of focus but the back of the car was in focus. The focus motor could turn fast enough it just could not anticipate where the car was going to be. It was the software - not the sdm motor letting me down.

I'm sorry I'm not good at online sarcasm to match your witty post
02-24-2009, 09:55 AM   #79
Banned




Join Date: Oct 2007
Location: Savannah, U.S./Baguio City, P.H.
Posts: 5,979
QuoteQuote:
It was the software - not the sdm motor letting me down.
Bingo.


you people should be complaining about SAFOX, not the 55mm.

seems like a bunch of crap to me. to make the improvements on an optical design that has been around for this long and was damn near perfect from the get go is outstanding, so I give a big thumbs up to Pentax for that. as for the PF... it exists, regardless of how much you pay for the lens, who's name is on it, or what optical design was used. period. a lot of technology goes into these lenses, it isn't quite the same as an all manual lens from the 60's. some of you people expect too much, and don't take the time to factor in what goes into a lens such as the 55mm. I understand, especially given the economic climate that even the small things become more prominent and have a much larger effect on purchasing decisions. I can understand this in regardless to the 55mm, but I believe some people here expect way to much and only set themselves up for a letdown. you say, OK a slightly better normal prime lens, and they want how much?... I think you are looking at it the wrong way. but I bet some of you same folks would drop mad cash for an A*85mm if you could, despite the 55 at this point at least on paper being a better lens. and its manual...

again complain about SAFOX not the lens. that's the real issue with AF speed.

02-24-2009, 10:42 AM   #80
Veteran Member
jsherman999's Avatar

Join Date: Dec 2007
Photos: Gallery
Posts: 8,228
.



Keep in mind that we're trying to pack a lot of opinion into a limited amount of raw material here.

It would be best to not form an intractable opinion until this lens has been loose in the field and the studio for a while, and we start seeing the images and user experiences pouring in.

As someone said earlier, based on first-month opinions of the FA 43ltd, that lens really sucked and was a major disappointment.

(not.)
02-25-2009, 12:29 AM   #81
Veteran Member
Steelski's Avatar

Join Date: Jan 2008
Location: Varna
Posts: 468
TO the OP,

I appreciate your doing a test, but Boy are you wrong in conclusion.
You think that the DA55 is a mild increase in optical quality.
Look again. The DA55 outresolves the FA 50 in the corner, at F1.4 the DA55 is as sharp or sharper than the FA at f5.6 in the corner. 1.4 vs 5.6 in the corner!!!!. WOW. This lens is almost completely defraction limited . what that means is that its sharp from the get go. I do not think we will know exactly how sharp this lens is unless pentax brings out a 20 MP APS-C sensor or higher.
Also the Bokeh is very pleasing in the foreground compared to many that I have seen. It is different from the FA.
02-25-2009, 01:20 AM   #82
Veteran Member
blende8's Avatar

Join Date: Feb 2007
Location: Bremen, Germany
Photos: Albums
Posts: 1,484
Original Poster
The only improvement in resolution is at f1.4 in the corner.
Contrast is improved slightly, perhaps 10% at f1.4.
Bokeh looks about the same, the circle of confusion is slightly smoother for the DA. Color rendition is the same.
I don't see the different league, some people are claiming.
(But if you think so, I'm fine with that.)

The lens is not bad.
To the contrary, but the difference to the FA50 is not that great, because the FA is already a very good lens, too.
Improvements over its 30 year old standard double gaussian design were expected and are fulfilled.
In my view the DA is a typical state-of-the-art lens with a rather slow AF, but, regrettably, not the holy grail.
02-25-2009, 01:53 AM   #83
Veteran Member
Steelski's Avatar

Join Date: Jan 2008
Location: Varna
Posts: 468
QuoteOriginally posted by blende8 Quote
The only improvement in resolution is at f1.4 in the corner.
Contrast is improved slightly, perhaps 10% at f1.4.
Bokeh looks about the same, the circle of confusion is slightly smoother for the DA. Color rendition is the same.
I don't see the different league, some people are claiming.
(But if you think so, I'm fine with that.)

The lens is not bad.
To the contrary, but the difference to the FA50 is not that great, because the FA is already a very good lens, too.
Improvements over its 30 year old standard double gaussian design were expected and are fulfilled.
In my view the DA is a typical state-of-the-art lens with a rather slow AF, but, regrettably, not the holy grail.
You fail to address what I pointed out, The DA55 is sharper at 1.4 in the corner than the FA at 5.6 in the corner. How is that a small improvement.
I have a feeling that if the MP race continues, then the DA55 will really shine.
Noone is saying the FA is a bad lens, what we are seeing is that the DA55 star has unparralelled sharpness at 1.4!!! Corner to corner.

02-25-2009, 02:30 AM   #84
Veteran Member




Join Date: Jan 2009
Location: Canada
Posts: 1,255
QuoteOriginally posted by lol101 Quote
Anyone else getting tired of hearing this kind of justification?
Here's something slightly on-topic, but somewhat comical: Did you ever look at Olympus's ad show-casing the speed of their AF, the one in photography magazines? It has a photo of some seal-like creature sticking its head out of the water. It's badly front focused.
02-25-2009, 02:52 AM   #85
Banned




Join Date: Oct 2007
Location: Savannah, U.S./Baguio City, P.H.
Posts: 5,979
QuoteOriginally posted by blende8 Quote
The only improvement in resolution is at f1.4 in the corner.
a big task given the already well improved on optical design
Contrast is improved slightly, perhaps 10% at f1.4.
see above statement
Bokeh looks about the same, the circle of confusion is slightly smoother for the DA. Color rendition is the same.
see above statement
I don't see the different league, some people are claiming.
(But if you think so, I'm fine with that.)
on paper its better than the legendary 85 1.4, its weather sealed, SDM, and most importantly available to all. again the AF speed issues are mostly with SAFOX not the lens. considering the street price, I think it will be a good deal for such a lens, particularly when compared to a similar nikon or canon offering.

The lens is not bad.
To the contrary, but the difference to the FA50 is not that great, because the FA is already a very good lens, too.
see first statement
Improvements over its 30 year old standard double gaussian design were expected and are fulfilled.
see first statement
In my view the DA is a typical state-of-the-art lens with a rather slow AF, but, regrettably, not the holy grail.
AF speed is again mostly due to SAFOX, but if you were expecting the 'holy grail' (what is that exactly?) then you were as I said in my previous post, expecting too much. maybe expecting what can't be given? can you name a nikon or canon lens in this class that can outperform it optically, for this price?
02-25-2009, 03:05 AM   #86
Pentaxian




Join Date: Jun 2008
Location: Flyover America
Posts: 4,475
QuoteOriginally posted by Steelski Quote
TO the OP, I appreciate your doing a test, but
Boy are you wrong in conclusion. You think that the DA55 is a mild
increase in optical quality. Look again. The DA55 outresolves the FA 50
in the corner, at F1.4 the DA55 is as sharp or sharper than the FA at
f5.6 in the corner. 1.4 vs 5.6 in the corner!!!!. WOW. This lens is
almost completely defraction limited . what that means is that its sharp
from the get go. I do not think we will know exactly how sharp this lens
is unless pentax brings out a 20 MP APS-C sensor or higher. Also the
Bokeh is very pleasing in the foreground compared to many that I have
seen. It is different from the FA.
and

QuoteOriginally posted by blende8 Quote
The only improvement in resolution is at f1.4 in
the corner. Contrast is improved slightly, perhaps 10% at f1.4. Bokeh
looks about the same, the circle of confusion is slightly
smoother for the DA. Color rendition is the same. I don't see the
different league, some people are claiming. (But if you think so, I'm
fine with that.)

The lens is not bad. To the contrary, but the difference to the
FA50 is not that great, because the FA is already a very good lens, too.
Improvements over its 30 year old standard double gaussian design were
expected and are fulfilled. In my view the DA is a typical
state-of-the-art lens with a rather slow AF, but, regrettably, not the
holy grail.
It seems to me that both of you are laboring under the assumption that
you evaluating objective optical performance when, in fact, you are
making subjective personal economic judgements about the relative worth
of the DA55 compared to the FA50.

My own take on it is that given the numerous and marginal improvements
that Pentax has made to the DA55 over the FA50 and the added production
costs this entails Pentax is probably asking a fair price for the DA55
in purely economic terms. It probably costs Pentax a fair amount just to
get that marginal improvement at f/1.4 in the corners compared to the
FA50 for instance.

The only question is what's it worth to you?
There is no right or wrong answer - just opinion.
02-25-2009, 05:55 AM   #87
Veteran Member
Steelski's Avatar

Join Date: Jan 2008
Location: Varna
Posts: 468
QuoteOriginally posted by wildman Quote
and



It seems to me that both of you are laboring under the assumption that
you evaluating objective optical performance when, in fact, you are
making subjective personal economic judgements about the relative worth
of the DA55 compared to the FA50.

My own take on it is that given the numerous and marginal improvements
that Pentax has made to the DA55 over the FA50 and the added production
costs this entails Pentax is probably asking a fair price for the DA55
in purely economic terms. It probably costs Pentax a fair amount just to
get that marginal improvement at f/1.4 in the corners compared to the
FA50 for instance.

The only question is what's it worth to you?
There is no right or wrong answer - just opinion.

I'm sorry, but the differace is not marginal. its extraordinary. When was the last time you saw a lens that was as sharp at 1.4 as the recent best is at 5.6?
You show me any lens that is that sharp in the corners at 1.4. Like every 1.4 50 of its era, the FA50 is not that great at 1.4. If you buy a lens designed to shoot at 1.4 but have to shoot it at 2.0 - 2.8 onwards to get decent results then what have you bought. This is why the F1.7 50 is so popular, its sharp in comparison from the get go, lighter and more economicaly friendly.
At last we have a 1.4 lens we can use from 1.4.
the other problem with the FA is that it simply looks horrible at 1.4. the A 50 1.2 managed to look great even though it was just as unsharp at the same apature.
I am not saying that the DA55 is some kind of miracle worker as it suffers from massive Purple fringing and CA, but there are situations where the 1.4 is far more practical than the FA ever would have been.
As far as AF goes. I'm not certain that the test that was performed has any merit. I know my 50-135mm moves the focus slowly, but when its close to the subject, it focuses quicker than any screwgrive lens I have. SDM vs screwdrive is not a simple matter of measurig how long the throw takes to navigate. it must take into account torque and accuracy. Granted I would like it to focus as quick as possible when moving from one subject to the next, but it might have a lot more to it.
I would like maybee overall impressions how it performs when the focus point is close, does it hunt much, how quickly does it micro adjust. Things which can not be measured easily but have just a high an impact in performance, and in particular sometimes this might make the differance between getting a lock or missing the situation.
02-25-2009, 06:37 AM   #88
Banned




Join Date: Oct 2007
Location: Savannah, U.S./Baguio City, P.H.
Posts: 5,979
QuoteQuote:
For the DA*55, it has been tested to have slower than the FA50/1.4, which is slow on AF already. And not surprisingly, SDM is known to be slow in general even against Pentax screw driven AF.
SDM wasn't meant to absolutely be faster, it was meant to be quieter. nikons and canons SDM style focusing, well maybe canon is ahead in this due to the fact that they have been playing the in lens AF game since the 80s. isn't really any faster than screw drive either. yes the hardware plays a part but its not the only part and as far as I understand it not the biggest part. as I have already stated twice in this thread, you should direct most of your AF complaints to the SAFOX system not the lens. the reason canon and nikon focus so much faster is the software.

if this is your biggest complaint about the lens, you are unfairly judging it.
02-25-2009, 06:54 AM   #89
Veteran Member
wlachan's Avatar

Join Date: Sep 2006
Location: Canada
Photos: Albums
Posts: 2,626
QuoteOriginally posted by Hapo Quote
Maybe the lens really is a dog, but I think it's more likely that a couple of the outstanding photographers on this site will get their hands on it, post some amazing shots, and everybody will suddenly be raving about this lens. Just look at what people said about the FA43 limited a few years ago to see what I mean. How long will that take, I wonder. One month? Three?
I were one of the few bashing the FA43 for its poor wide open sharpness, poor corner sharpness stopped down and barrel distortion. FA43 is still the same FA43 but everyone is shooting and testing it on APS-C now which only sees the centre portion of the image circle. So the poor corner sharpness has gone and the barrel distortion has become less obvious. However, the poor wide open sharpness remains even with APS-C.

For the DA*55, it has been tested to have slower than the FA50/1.4, which is slow on AF already. And not surprisingly, SDM is known to be slow in general even against Pentax screw driven AF. That does not mean it is incapable of producing awesome images, just when you need it fast to lock focus, it won't. Any experience photographers know any lens can produce great images given the right skill and condition, but that doesn't stop those lenses being tested and evaluated.

QuoteOriginally posted by kunik Quote
As for focus speed - Its a portrait lens. I'll have to tell my brides to slow down as they run down the isle
I have been shooting people most of the time and AF speed is a big deal. Even if the person stayed still, a moment of hestitation and the facial expression would be gone. And when people walk, the AF struggles more. I could still obtain some great shots, but many more would be OOF and being trashed. That was the sole reason I bought the 40D for such occasions. Man it just focus and the success rate is so much better. I see that the Km has some +ve improvement in AF and let's hope something +ve would be shown in PMA too. I am still waiting for a fast AF Pentax body so that I can use my Pentax primes fully.

QuoteOriginally posted by blende8 Quote
The argumentation that the AF of the DA55 is slow because it is a portrait lens does not hold.
QuoteOriginally posted by Wheatfield Quote
That's an apology for poor performance.
It's a short telephoto lens, it should have AF as fast as any other lens.
Ditto.

QuoteOriginally posted by kunik Quote
Its not an apology, its just a fact. I know I won't notice a difference so why should I care. I have yet to see any numbers as to just how slow it is so I would hold off on final judgment until I see some numbers or try the lens myself. Do you know if or by how much this is slower than Sigma/Canon/Nikon?. Some people demand a minivan that handles like a sports car. I know that Pentax does not handle like a sports car and they do not need to apologize to me for that.

Without some sort of predictive ability the focus speed of a pentax lens will not matter to me. My fastest focusing Pentax lens (in my subjective opinion) is my 300/2.8. I can't really be certain if it focuses faster than my Canon 1DmkIII with its 70-200/2.8 lens, because the Canon has AI Servo. So ultimately the Canon does a much better job of focusing on fast moving objects but is that because of AI or focus speed?

I can definitely tell the SDM motors turn a little slow on long throws (on my DA* lenses) but its more quirky than annoying for me. Now when Pentax comes out with a sports oriented body it might start to matter more but until then it works fine for me.

edit - I don't intend to be argumentative but when people start complaining about Pentax on a public forum about things that matter to them but do not matter to me I think its valuable to include a note representing an alternative point of view. Pentax does not sponsor me and they never replied to my request for participation in their professional program but I sincerely enjoy their gear and I honestly don't consider the so-called negative points about Pentax to be a concern for me. I've been shooting a $4000 Canon for 4 months now and I can honestly say I still prefer my K20D (and I've take more than 20,000 pics in that time - between the two brands). The different bodies and lenses require different techniques to achieve good results but although saying "Pentax has slow focus" may be factually correct in relation to the Canon it does not prevent me from getting the images I want so does it really matter?
You have your own preferences, others express theirs? What's the problem?
02-25-2009, 06:57 AM   #90
Pentaxian
gazonk's Avatar

Join Date: Feb 2009
Location: Oslo area, Norway
Photos: Gallery | Albums
Posts: 3,512
QuoteOriginally posted by séamuis Quote
you should direct most of your AF complaints to the SAFOX system not the lens.
But if it's the SAFOX system, how come it is slower than the FA? Since it's sharper and has better contrast, one would think that it would have less trouble focusing. And the FA isn't fast either, is it? I tried to find comparable numbers for the FA50 and the DA70 (which I suppose is much faster), but couldn't find any.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
da55, fa50, k-mount, pentax lens, results, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
The DA55 on the K-7 blende8 Pentax SLR Lens Discussion 20 06-05-2009 04:11 AM
A DA55/1.4 is now in my bag Wheatfield Pentax SLR Lens Discussion 5 03-20-2009 03:28 AM
DA55-300 + Promaster 1.7x TC heatherslightbox Pentax SLR Lens Discussion 16 09-06-2008 10:51 PM
DA55-300 + Kenko 1.5x TC heatherslightbox Pentax SLR Lens Discussion 7 08-20-2008 07:19 AM
So let's try this again: DA55-300 applejax Pentax SLR Lens Discussion 0 06-13-2008 09:05 AM



All times are GMT -7. The time now is 11:41 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top