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Forum: Pentax SLR Lens Discussion
02-05-2012, 07:50 AM
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also if this was true shouldn't manual lenses expose the same problem? I have a manual 50 f2. I usually use it with the "catch in focus" function and most of the time gives me decent focused shots.
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Forum: Pentax SLR Lens Discussion
02-05-2012, 07:47 AM
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searching about my problem i came among other links to this one which demonstrates a problem very similar to mine.
https://www.pentaxforums.com/forums/pentax-beginners-corner-q/138605-back-focus-problem.html
So, what's the bottom line? Are we going to accept as a fact that pentax has a crappy center focus point and there's nothing we can do? This doesn't make any sense! Pentax offers many large aperture lens! I can't accept the fact that pentax uses a sensor that can't perform acceptable at large apertures and then sells cheap large aperture lenses! How can somebody overcome this "large center focus sensor" problem?
what others do to counteract this problem?
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Forum: Pentax SLR Lens Discussion
02-04-2012, 06:25 AM
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marc that's an orthological way to see it and believe me i tried. that's why i'm posting here, trying to keep the lens cause i like it. Anyhow for me it's a big inconvinience to have to send the lens back to england and wait for a new one... The autofocus continuous mode didn't make a big difference
Just a long shot: does anybody has any idea if i can reduce, in K-x debug mode, the size of the center autofocus region?
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Forum: Pentax DSLR Discussion
02-03-2012, 06:17 AM
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i should remind you that k-x's main opposition was d5000. Actually they came out almost at the same time. d5100 came out later so maybe we should rate it against maybe kr?
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Forum: Pentax SLR Lens Discussion
02-03-2012, 01:51 AM
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update: putting the k-x in autofocus continuous seems to improve things a lot. going for some more test shots ...
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Forum: Pentax SLR Lens Discussion
02-02-2012, 10:07 PM
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marc i don't quite understand what you are saying. those where a few representative shots of about 1200 shots taken at a trip. i use the tamron which by the way is a much inferior lens, for more than 3 years and now i have to start to learn to be more carefull? any crossreference to tamron was at the same aperture (f4) not at f2.4. all night shots are out of focus. most of any shot taken of a distanstant subject is soft. i never said that tamron is a better lens. i just find my copy of 35mm unable to focus.
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Forum: Pentax SLR Lens Discussion
02-02-2012, 04:45 PM
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Forum: Pentax SLR Lens Discussion
02-02-2012, 04:04 PM
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i also bought new, stocked item, from a respectable seller in UK Through Ebay. I contacted him and he told me to send the lens back. I'm trying to figure out if i'm going to ask for a replacement, or go for the tamron 17-50 (which is also a risk, knowing all the back/front focus issues). It's true though that when i searched for 35 f2.4 i didn't find significant reports about "bad copies".
But what actually puzzles me is that at close range this lens is superb! Focuses fast and sharp! Also i've noticed that even though i set it at f2.4 when i try to focus on different subjects that are not far apart, the camera won't refocus. I'm starting to think that there might be somekind of incompatibility between k-x and 35 f2.4?
i'll post some pics showing tamron and 35 f2,4 behaviour
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Forum: Pentax SLR Lens Discussion
02-02-2012, 09:58 AM
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i agree with you on that it just seemed very similar to the results i was getting
http://www.flickr.com/photos/75762547@N03/
I've uploaded some of the files on flickr (i haven't used it before. I uploaded in full resolution but i don't know if you can download the full file. As mark pointed out in previous post compression makes some details less obvious). So if somebody has the patience to take a look please share your opinion. Thanks.
01. Pentax Back Focus 01 - focus was on the man but the pic is sharp behind him
02. Pentax Backfocus 02 - Focus was on red window, pic is sharp behind it
03. Pentax f2.4 on buildings - Focus is on buildings which are very blurry. doesn't show well in the compressed image. tell me a way to upload the original.
04. Pentax Strange Behaviour - Focus was on buildings behind which are sharp enough but the strange thing is that the tree branches on the right are Sharp while the yellow leafs are blurry. Doesn't show very well in this compressed image. In full size image it's very pronounced. (please tell me a way to upload full sized image)
05. Pentax strange behaviour - Buildings are sharp but this time the focus was on lamp pole, yellow leafs are sharper than right branches.
06. Iceskate- focusing in front otherwise skaters look blurry like in next photo
07. Strange behaviour again - Right part sharper than left part. Skaters blurry
08. 01. Pentax autofocus. Best i could get but focused on girls
09. 01. Otherwise best i could get is this
10. 01. pentax f8 manual focus. Actually very nice...
11. Pentax 10000000th attempt. worse results than tamron
12. Tamron first attempt. Acceptable focus.
13. Tamron monument - Photo of the monument taken with tamron at f4 - sharp no need for second focus attempt
14. Pentax monument - Blurry. not accurate focus
I haven't used flickr before so i don't know if you can download the full sized image. Actually i think that compression doesn't show the problem in some of the pics while it exaggerates it on some others. if anybody is intrested please pm me to mail the original images. |
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Forum: Pentax DSLR Discussion
02-02-2012, 05:55 AM
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as far as i'm concerned i've tried a few friend's gear like, nikon d40, d90, d5000, canon 450d, 500d. some of these cameras are considered to be in k-x's league, and some considered out of it's league. All of my friends mocked me about my choice of a pentax k-x. When the time came for tests all of them shoved their gear in their bags. Finally, besides the speed and quality of the camera, the common question was "whow! your's has also this feature?".
jump on whatever boat you think it's better but i think that the cameras you own belong to the "old", if i may say, generation of pentax. If you are ready to try another brand why don't you first have a test on a k-5? maybe this way you'll save some money and a lot of frustration!
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Forum: Pentax SLR Lens Discussion
02-02-2012, 05:37 AM
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looking around about my problem i bumped on this site
PENTAX - smc PENTAX DA 35mm F2.4 AL
Look at the picture of Zakynthos wreck. (the cliff and the sea)
this picture to me looks very soft, as if it's misfocused! If this is a common issue about this lens still needs to be clarified...
anyway i'll post my images from budapest in the evening...
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Forum: Pentax K-5 & K-5 II
02-02-2012, 05:23 AM
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there are videos in youtube showing focus speed of both cameras. Although k5 seems extremely fast i can tell you by owing a kx that it's focus speed is absolutely great. Of course lenses always play a major role in focus speed and accuracy. But i can tell you that those numbers in the technical booklet about k.x are real.
now if you are intrested in technical details here they are:
Pentax K-5 Camera Performance - Full Review
Pentax K-x Camera Performance - Full Review
actually kx seems a bit faster in numbers. I don't know about k5 as i've never used one but i think that k-x is one of the best bargains pentax ever made!!!
if you want just for the fun of it, check this out...
Canon EOS 60D Camera Performance - Full Review
twice the price twice the delay... feel free to check out similar nikons....
but the bottom line is that k5 is much much much better camera than k-x when it comes to ease of use and custom settings...
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Forum: Troubleshooting and Beginner Help
02-02-2012, 04:52 AM
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this thing happens every the time my K-x tries to write to the memory card and suddenly is left withouth battery juice...
this matrix-like lines apperar. It's not a problem at all maybe your batteries where down in power?
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Forum: Pentax SLR Lens Discussion
02-02-2012, 12:46 AM
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considering the fact that this lens has no distance scale i couldn't set hyperfocal distance, but i've tried manual focusing till i could get an acceptable pic (even then tamron seemed sharper), but no matter how i tried, i couldn't get acceptable focus with autofocus. Tamron hunts a bit but gets the job done. I'll post some pics. even though it's not a scientific approach it will show the problem. I'll even post some pics that show strange behaviour (clearer focus on the right part of the pic while the left part seems soft even though i had center fovus point). I'll post as soon as i get home in the evening
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Forum: Pentax SLR Lens Discussion
02-01-2012, 02:27 AM
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i tried manual focus but it doesn't get any better. What puzzles me though is that at close distance (portraits) even at f2,4 the lens focuses fast and accuretly
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Forum: Pentax SLR Lens Discussion
02-01-2012, 01:27 AM
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Hello everybody this is my first post here, sadly with a problem...
I bought the pentax 35mm f2.4. At first i was impressed by how good it was. Especially at portraits and close range subjects. Then i noticed some softness when i was trying to focus on distant subjects. Most of the time they were out of focus. Then i tried to focus to infinity but i found out that this was not possible. Raising aperture at f4 somewhat remedys the problem but doesn't eliminate it. I thougth to fiddle with the K-x debug menu but instead i decided to test it against a tamron 18-250 at 35mm and f4. Bottomline, the tamron always outperformed the pentax lens when it came to far away subjects. Not to mention that the Tamron lens focuses to infinity easily.
now the question is, is that possible? Does such a defect exists (near focus is sharp but at longer distances is very soft) or this is normal behaviour for this kind of lens? I'm asking because right now i have two choices.
First is to return the lens to the shop and accept a replacement or pay the extra money and buy the tamron 17-50.
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