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05-21-2009, 01:10 PM   #16
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QuoteOriginally posted by Arpe Quote
Obviously it's not bad that it does correct those, that's good. But what about the FAs that are still being sold and FA*s? I have an FA35 and FA50, do they need any "correcting"?
QuoteOriginally posted by Rondec Quote
I think Pentax felt that they wanted to "encourage" users to buy newer lenses. Also, I am sure there is a limit to the lenses that you can put in your database. Their explanation is that the DA and DFA lenses are already "optimized for digital" and therefore it made sense to tweak their performance.
$10 says it's extra information added to the in-lens chip - thus older FA series lenses lack the extra information needed for the camera to pull this off. Chances are Pentax has been working on this for a while.

Note that this would be exactly the same as the F series lenses which lack the MTF data the FA series lenses provide...

05-21-2009, 01:25 PM   #17
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The camera seems to know what lens it's using (at least with the FA's--don't have any F's), so I'm not sure why they couldn't do at least the distortion correction (x lens gets x correction).

The CA stuff, I can see that getting difficult--the DA lenses at least have a consistent CA pattern across the range, so it's probably a quick fix to do those.

But on the other hand, we're criticizing a feature that we didn't even know existed before yesterday, that no other camera maker has! That's a bit ungrateful, i'n'it?
05-21-2009, 02:16 PM   #18
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Most people seem to be assuming this is done with an in-camera database. It's not; the necessary information is encoded in the lens and sent to the camera. (It's also present in the EXIF data; when the next version of the Pentax software is available, it should work for everyone's current cameras in post.)

In general, consumer electronics manufacturers are reluctant to put time-sensitive databases in devices, both because they take significant firmware space, and because updating them is a nightmare and the logistics for third-party support are impossible. Imagine if Pentax came out with a new lens two years from now, and they didn't want to update the database in your out-of-production K-7 anymore...
05-21-2009, 02:28 PM   #19
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I honestly don't think so. You can't even compare it to Canon because only EF lenses work on their 50D.

05-21-2009, 04:26 PM   #20
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Those of you use DxO know that the program is 390 Mb. The lens modules are a significant size as well. Note that DxO corrects the distortion and vignetting while taking into account the focal length setting, the focus distance and the aperture. I'm not sure they don't include the shutter speed as well. The algorithms are extremely complex.
05-21-2009, 04:51 PM   #21
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Still, at least the 3 FA Limiteds should have been included. Those are premium lenses that are still sold, so this support would be really nice. I hope they will be added later in a firmware upgrade.
05-21-2009, 05:35 PM   #22
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QuoteOriginally posted by naht Quote
Still, at least the 3 FA Limiteds should have been included. Those are premium lenses that are still sold, so this support would be really nice. I hope they will be added later in a firmware upgrade.
Oh, I'm sure they could include this info on the chip in the FA limiteds and even the FA50 and FA35, but only on copies that are made new from now on, so this feature would not work on any of your old lens copies anyway...imagine what a lot of complains that would cause, and what problem it would be to know if you get an old or a new version when you buy a used lens...but if they ever go FF and re-release lenses such as DFA 50mm/1.4 II, DFA*85/1.4 II, DFA*200/4 II macro etc, they will have this info on their chips.
05-21-2009, 05:38 PM   #23
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QuoteOriginally posted by panoguy Quote
Nice that it can be disabled as well, since I kinda like the distortion of my DA 10-17mm!
Pentax have stated that the distorsion correction will not be applied on the fisheye zoom at all, which is quite logical since it is not a defect, but an effect on this lens.

From pentaximaging web page:

"Lens Correction function
A Lens Correction function adjusts for Distortion and Lateral Chromatic Aberrations, allowing you to maximize your image quality for every digital lens.*

* Compatible with D FA, DA, DA Limited and DA Star lenses. Distortion correction is not applied to the DA 10-17mm Fisheye lens. "

05-21-2009, 05:47 PM   #24
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QuoteOriginally posted by mut@NT Quote
The correction applies only to jpegs, so why bother... I don't remember last time I shot jpeg.
Didn't know that. I've found Adobe RAW can't get rid of some of my CA.

QuoteOriginally posted by Quension Quote
Most people seem to be assuming this is done with an in-camera database. It's not; the necessary information is encoded in the lens and sent to the camera. (It's also present in the EXIF data; when the next version of the Pentax software is available, it should work for everyone's current cameras in post.)
Aaah, no, did not realise that.
05-22-2009, 05:53 AM   #25
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QuoteOriginally posted by Mike.P Quote
Yes I was joking, British sense of humour again


I must admit I have been thinking of the D300 for a while now as my K10D is getting on a bit but the K-7 has sorted that problem out for me.
The K-7 should be a good DSLR to replace your K10D.

i am already dreaming about it, but i just got my K20D in late March '09
05-22-2009, 08:00 AM   #26
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QuoteOriginally posted by mut@NT Quote
The correction applies only to jpegs, so why bother... I don't remember last time I shot jpeg.
Not according to John Carlson (Pentax USA product manager), I hope this is true:

Re: K-7 Feature Questions: Pentax SLR Talk Forum: Digital Photography Review

Joseph Tainter wrote:
> Re:
>
> --Distortion/CA correction
> --HDR
> --D-Range Setting
>
> John, does these work in RAW or are they only for JPEGs?
>
> Thanks,
>
> Joe

HDR does not, the other two do.

--
John C.
05-24-2009, 03:44 PM   #27
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Old lenses could be supported by allowing manual entry of correction parameters. Just like you enter focal lengths for manual lenses, you could do that for lens correction parameters. If several profiles were supported (coupled with the AF adjustment values), this could easily support old lenses.

Although it would be nice to have, I guess one shouldn't fault Pentax for enticing people to buy their new glass.
05-24-2009, 03:48 PM   #28
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QuoteOriginally posted by ManuH Quote
Not according to John Carlson (Pentax USA product manager), I hope this is true:
If find this very hard to believe. Is there a way to apply PF correction independently of image content before demosaicing?

BTW, the FA 50 has negligible geometric distortion, so shouldn't need correction in this department. PF is another matter, I think.
05-24-2009, 10:09 PM   #29
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QuoteOriginally posted by Class A Quote
If find this very hard to believe. Is there a way to apply PF correction independently of image content before demosaicing?

BTW, the FA 50 has negligible geometric distortion, so shouldn't need correction in this department. PF is another matter, I think.
Yes, distorsion is only 0.08%, one of the best! (Pentax Pentax SMCP-FA 50mm f/1.4 AF - Lens Review from Experts at Popular Photography- Photo Tips)
05-25-2009, 09:18 AM   #30
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QuoteOriginally posted by Class A Quote
Old lenses could be supported by allowing manual entry of correction parameters. Just like you enter focal lengths for manual lenses, you could do that for lens correction parameters. If several profiles were supported (coupled with the AF adjustment values), this could easily support old lenses.

Although it would be nice to have, I guess one shouldn't fault Pentax for enticing people to buy their new glass.
I do not think that it is as simple as this. Correcting simple geometric distortion from older prime lenses might be possible, provided the distortion is simple. I think close examination of the images from recent lenses would show moustache distortion used by the designers to greatly reduce the apparent distortion. Correcting moustache distortion just is not possible without some really heavy duty software. Applying distortion correction to a zoom lens requires knowledge of the focal length setting at the time of exposure. That eliminates all the zoom lenses that do not "talk" to the camera body.

Chromatic aberrations add an entirely new level of complexity. As the aperture changes, so does the chromatic aberration, as less light is added from the perimeter of the lens elements, reducing in turn the amount of prismatic errors.

There are just too many factors to be considered in the corrections to allow user input of correction parameters, in my opinion.
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