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Forum: Pentax Price Watch
10-19-2013, 08:41 AM
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If only, but I don't have the 15, actually. ;) I have the Samyang 14mm/2.8, but the 15 would be perfect for what he wants to shoot.
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Forum: Pentax News and Rumors
10-19-2013, 08:33 AM
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No it does not. We do not refer to others with offensive names here.
This is a friendly community. :)
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Forum: Pentax News and Rumors
10-07-2013, 07:54 PM
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Santa sometimes comes in January too :)
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Forum: Welcomes and Introductions
08-25-2013, 01:02 PM
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Thanks for your images ... J
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Forum: Pentax Price Watch
04-29-2013, 03:15 PM
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Download a full version of the well-regarded DxO Optics Pro RAW processor/image editor (v6) for free, courtesy of DxO and the German 'Fotohits' magazine.
Steps:
Follow the Promo Link
Enter you email address
Press "BESTÄTIGEN"
You will then be taken to the download page for the Windows and Mac version of DxO v6.
(NB: The promo and download pages are in German).
The latest version of DxO is v.8, but this older v6 fully supports the following Pentax camera bodies:
Pentax K10D
Pentax K20D
Pentax K200D
Pentax K-5
Pentax K-7
Pentax K-m
Pentax K-r
Pentax K-x
as well as lots of Canon, Nikon, Sony etc bodies too, which are listed in this PDF (28k). As this is the Elite edition, some full-frame bodies are also supported.
Bodies later than the above Pentax models (K-30, K-5IIs etc) will still work, as DxO v6 will still open DNG's (and perhaps PEFs) from later Pentax bodies.
This v6 also appears to allow you to download and use all of the appropriate DxO lens modules created to date, which means the 30 or so DxO modules for Pentax lenses should also work with it.
A great opportunity to try out DxO if you haven't used it before. An upgrade deal to DxO Optics Pro v8 is also available on the download page.
Offer expires 22 May 2013.
Found this originally on ozbargain |
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Forum: Pentax DSLR and Camera Articles
04-02-2013, 11:34 AM
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This problem is discussed in a couple of earlier threads in the K-01 section. There, it seems the user was setting a combination of low-medium ISO and fast shutter speed that was causing the camera to hold the aperture open wide--and most lenses aren't their sharpest wide open.
Take some shots in Av with the aperture stopped down to f/8 or smaller and see if you have the blur problem.
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Forum: Lens Clubs
04-02-2013, 12:07 PM
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Manual Focusing is an art :)
But it looks like you're getting there, practice makes perfect. Even handheld with Shake Reduction, your Shutter Speed of 1/320 may not have been fast enough OR be careful where you set your SR... this too is a form of art :)
I do have the 75-205/3.8 mine is a push pull zoom and is called "Macro Focusing Zoom" and it is very sharp throughout the focal length even wide open.
K10D + Vivitar 135/2.8 Auto Telephoto Close Focusing (m42)
Rusted Ornament by theunartist, on Flickr
Akimbo by theunartist, on Flickr
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Forum: Photographic Technique
03-22-2013, 04:28 AM
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The part about zoom and prime lenses, you can see the difference in "focal length" and changing perspective (point of view).
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Forum: Pentax SLR Lens Discussion
02-25-2013, 12:17 PM
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The bricks look different to me. The images look less noisy and distorted. They also look much sharper and clearer. What type of lighting was there in the newspaper ads shots?
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Forum: Pentax SLR Lens Discussion
02-25-2013, 01:33 PM
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It is the nature of lenses to be less sharp in the corners than in the center, especially wide open. This is borne out by your testing. Most "real" pictures are composed so that the subject is not in the extreme corners, so this corner softness is not a big deal.
If you experiment with different f-stops, you'll find that the sharpness improves with stopping down. Usually optimum sharpness is obtained 2 stops or so down from wide open. This is what people call the "sweet spot". If you stop down further, you'll get more depth of field, but sharpness will decrease due to diffraction.
I suggest you find your sweet spot and go out and take some real pictures and see if they are sharp enough in the subject area. If there is a sudden drop off of sharpness, or one side of the frame is considerably less sharp than the other, then you have a problem. Otherwise you're fine.
You can't expect corner to corner razor sharpness from a consumer zoom. I suspect that if you shipped it back to Sigma for evaluation, they'd tell you your lens was performing within specifications.
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Forum: Pentax SLR Lens Discussion
02-25-2013, 02:34 PM
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The UWA lenses are likely to be significantly less sharp at the edges. I would personally compare against the tests at somewhere like DPReview, but I'm not too concerned, these are the far corners of the lens after all.
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Forum: Pentax SLR Lens Discussion
02-25-2013, 03:13 PM
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Forum: Pentax SLR Lens Discussion
02-25-2013, 03:37 PM
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Erm, why do you choose F4 and F16? F8 should be sharper than F16.
But what this shows is that there is field curvature, and when you focus on the middle of the wall/ad, there is not enough depth of field to include the corners. At F16, they are fully in focus.
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Forum: Pentax SLR Lens Discussion
02-26-2013, 07:45 PM
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My 10-20mm is sharp at pretty much any focal length or aperture, but I can't say that I've every really pixel-peeped the extreme corners. I'm at work right now, but when I get home I'll go through my pictures and look at some of the corners.
In the meantime, here are a couple pics from my 10-20mm that I've posted before (and therefore I already have them uploaded). They're both shot handheld (at fairly slow shutter speeds) at 10mm and f4, but I think they do a good job of demonstrating how sharp the lens is across most of the frame, even wide open at the extreme wide angle. Click on the pictures to download the full-size 16MP image.
Unfortunately, neither of the pictures is suitable for pixel-peeping the corners. (But like somebody else pointed out above, you probably won't be too worried about the extreme corners in most pictures).
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Forum: Pentax SLR Lens Discussion
02-27-2013, 09:29 PM
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Forum: Pentax SLR Lens Discussion
03-01-2013, 06:55 AM
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I would suggest that you look at your shots fromthe amphitheater or of the headstones and analyze them. I think you might be happy with the results and feel more confidence in your lens.
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Forum: Pentax SLR Lens Discussion
03-01-2013, 08:47 PM
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I think you may not realize that it's not necessarily a binary judgement of being defective or not. There's a spectrum of performance consistency, from theoretically perfect to obviously horrible. Most lenses fall somewhere in between.
Paul
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Forum: Pentax SLR Lens Discussion
03-02-2013, 06:38 AM
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To me it doesn't look like it. Looks like it's performing within standards. There's a chance it's a little soft, but this lens is never great at the extreme corners anyway. I think your copy sharpens up nicely. And I agree with a prior poster that f16 really isn't (or shouldn't be) the sharpest aperture for the lens. You're looking around f7.1-f8 for that.
Enjoy your vacation and your new lens!
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Forum: Pentax SLR Lens Discussion
03-02-2013, 06:00 AM
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Great, This is what counts. Enjoy your vacation and your pictures / lens.
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Forum: Pentax SLR Lens Discussion
02-27-2013, 11:07 AM
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F = Autofocus, auto-aperture
FA = Autofocus, auto-aperture
A = manual focus, auto-aperture (all have an "A" setting)
M42 = manual focus, manual aperture, no green button, viewfinder becomes dimmer as you stop down
K = manual focus, manual aperture, use green button
MK = manual focus, manual aperture, use green button
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Forum: General Talk
02-24-2013, 03:09 PM
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Sorry, I don't share my design ideas for less than a 77mm f1.8 Limited. :cool:
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Forum: Pentax SLR Lens Discussion
02-12-2013, 02:08 PM
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No, won't work. The 8-16 doesn't even have any threads to attach filters (or adapter rings).
I've never used the 10-20, but I would expect that lens to vignette on the wide end with the Cokin P filter system. Even with the wide angle adapter, Cokin P filters usually begin vignetting around 13 or 14mm on APS-C lenses. You'll need a larger filter system for these ultra-wide lenses, like the Cokin Z-pro or the Lee filter system. That also means some fairly pricey, larger filters. You may want to reevaluate whether you need ND filters at ultra wide fovs; or start saving your money.
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