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Strange output from DNG files, JPG are normal

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Offline outslider

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Re: Strange output from DNG files, JPG are normal
« Reply #10 on: 16 / February / 2012, 13:35:54 »
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In many cases cameras which natively support RAW have better lens (to provide better RAWs). Cheap cameras with worse lens (big disortion, sometimes chromatic aberration) doesn't support RAW. So you shouldn't be amazed by such disortion.

SX130, which I own, has this effect on the same level (and has little chromatic aberration). Of course JPGs are good.
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Offline waterwingz

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Re: Strange output from DNG files, JPG are normal
« Reply #11 on: 16 / February / 2012, 14:12:52 »
Quote from: stalker78 on 16 / February / 2012, 13:22:46
RAW with such distortion? I have another camera - Nikon D40x - and when I'm taking photos in NEF (internal Nikon RAW format) I got same files as in JPG; maybe slightly different colours which I correct in DCRaw but without any barrel distortion.
A quick look at the lens on your DSLR compared to the lens on your P&S camera should explain the situation to you ...
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Offline Microfunguy

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Re: Strange output from DNG files, JPG are normal
« Reply #12 on: 16 / February / 2012, 14:22:18 »
It is unfortunate that so many people request a CHDK port for their camera simply, or mainly, for so-called raw support.

They seem to think they are getting DSLR quality for free.

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Offline waterwingz

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Re: Strange output from DNG files, JPG are normal
« Reply #13 on: 16 / February / 2012, 14:30:52 »
Quote from: Microfunguy on 16 / February / 2012, 14:22:18
It is unfortunate that so many people request a CHDK port for their camera simply, or mainly, for so-called raw support.  They seem to think they are getting DSLR quality for free.
That is a problem. 

However,  there are also some who are convinced they get better pictures in the end through post-processing those raws rather than working with the native jpg images.

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Offline Pier

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Re: Strange output from DNG files, JPG are normal
« Reply #14 on: 16 / February / 2012, 16:51:08 »
Quote
waterwingz wrote:A quick look at the lens on your DSLR compared to the lens on your P&S camera should explain the situation to you ...

Quote
outslider wrote:SX130, which I own, has this effect on the same level (and has little chromatic aberration). Of course JPGs are good.
Yes, on wide angel Lens like in P&S this distortion is normal.Just finished to play with RAW (DNG) file from my SX130IS.I'm usin Lightroom 3.6 and take a time to correct those distortin's-only Manual with several sliders.
Result is much better than same JPEG created with SX130IS Firmware. There are many Lens correting profiles build-in LR but unfortunately not for SX130IS.I will try to make such one for SX130IS in accordans with Adobe Lens profile creator sofware (it's free).
« Last Edit: 16 / February / 2012, 16:58:15 by Pier »
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Offline Microfunguy

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Re: Strange output from DNG files, JPG are normal
« Reply #15 on: 16 / February / 2012, 17:31:51 »
Quote from: Pier on 16 / February / 2012, 16:51:08
Result is much better than same JPEG created with SX130IS Firmware.

Could you post an original, unprocessed camera JPG, the raw file and your finished image and explain what you think the improvements are ?
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Offline Pier

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Re: Strange output from DNG files, JPG are normal
« Reply #16 on: 17 / February / 2012, 05:19:47 »
@Microfunguy

Well, unfortunately yestarday"s pisture was deleted, but I take another one for short test.
Maybe it is not so "much better"    compared with the native JPG.Have not much time to play
with all the sliders and "knobs"...especialy in the upper side of the picture but the difference is clear visible.
These distortion's will only be occur with wide angel Lens when shooting from close
distance..Ithink.
Yes, the better way is to have good working Lens correction profile, and the mess with the sliders to be minimal !
I can't upload RAW (DNG) file and other two full sizeJPG's-ZIP file is 20 MB.Attachment is limited..sorry
« Last Edit: 17 / February / 2012, 05:28:18 by Pier »
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Offline Microfunguy

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Re: Strange output from DNG files, JPG are normal
« Reply #17 on: 17 / February / 2012, 07:28:00 »
Quote from: Pier on 17 / February / 2012, 05:19:47
Maybe it is not so "much better"    compared with the native JPG.

Hmmm ...

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I can't upload RAW (DNG) file and other two full sizeJPG's-ZIP file is 20 MB.Attachment is limited..sorry

There are various sites you can upload to.
Member ntstatic has just used http://www.4shared.com to upload a 78 MB movie for me, so there is no excuse !   :)

Anyway. so far no-one who has claimed the raw files are better than the JPG has been able to prove it.
« Last Edit: 17 / February / 2012, 07:33:56 by Microfunguy »
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Offline Pier

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Re: Strange output from DNG files, JPG are normal
« Reply #18 on: 17 / February / 2012, 08:57:00 »
@Microfunguy

Thanks for the link to upload.Very nice ! BTW This was my first uplod - never do that B4.
Ziped files are uploaded and shared to every one.
Must say ones again - this was quick develop of DNG file... "on the fly" for experiment only. :)
It is possiible to do things much better.RAW Rulzzz.
The link:
http://www.4shared.com/folder/Nk6ILUiN/_online.html
« Last Edit: 17 / February / 2012, 09:02:29 by Pier »
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Offline Lebeau

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Re: Strange output from DNG files, JPG are normal
« Reply #19 on: 17 / February / 2012, 10:10:19 »
Concerning fish-eye effect of the raw, not apparent on jpeg, it's caused by the "real" focal length. My SX230hs has the same effect when focal is about 5 mm (wide angle), It's not concerning lens quality at all.

Any lens produce a circle of luminosity (cylindric symmetry). That circle has a focal plane that is not flat. That surface is parabolic-like. When the center of that surface reach and "touch" the sensor, the sensor's center is at the focal point. The surface plane is never "touching" the sensor surround. Therefore, the sensor surround is capturing out-of-focus photons.

More the mm is low, more the focal plane is parabolic, and more great is the fish-eye effect. For larger mm, the focal plane is less parabolic (less fish-eye effect) and the sensor's plane is within depth-of-field cleaness (surround cleaner).

The cam hardware processor is applying lens correction in real time (for LCD display), upon current "real" focal length. The jpeg file is processed from the raw data and lens corrected also. On the other side, your are able to manually correct raw data in post-process as you wish, that's raw data, irrelevant to cam quality.

P.S.: Friends of mine bought high quality lenses for DSLR and when they move from "normal"DSLR to "full-frame" DSLR, the "famous" lenses appear to have vignetting because the luminous circle overcome the sensor area :(
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