Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
05-05-2009, 11:54 AM   #1
Site Supporter
Site Supporter
ManuH's Avatar

Join Date: Dec 2007
Location: Montreal
Photos: Gallery | Albums
Posts: 1,249
Does Pentax applies NR to its RAW files?

Read this:

DxOMark-review-for-Pentax-cameras

"Noise filtering processing is present on the Pentax K10D (ISO 800 and ISO 1600), the Pentax K20D (ISO 3200 and ISO 6400), and the Pentax K200D (ISO 800 and ISO 3200)."

(Note, for the K200D it's a typo, the K200D does not have a 3200 ISO).

"However, while most other cameras have an interface that permits turning off internal noise filtering and thus providing unprocessed RAW data files, Pentax cameras still apply some noise reduction even when the noise reduction option is supposedly switched off."

That is extremely disapointing if true.

05-05-2009, 12:28 PM   #2
Veteran Member
deejjjaaaa's Avatar

Join Date: May 2007
Location: steel city / rust belt
Posts: 2,043
QuoteOriginally posted by ManuH Quote
Read this:

DxOMark-review-for-Pentax-cameras

"Noise filtering processing is present on the Pentax K10D (ISO 800 and ISO 1600), the Pentax K20D (ISO 3200 and ISO 6400), and the Pentax K200D (ISO 800 and ISO 3200)."

(Note, for the K200D it's a typo, the K200D does not have a 3200 ISO).

"However, while most other cameras have an interface that permits turning off internal noise filtering and thus providing unprocessed RAW data files, Pentax cameras still apply some noise reduction even when the noise reduction option is supposedly switched off."

That is extremely disapointing if true.
at this point you can start googling for gordonbgood AND/OR oleg_v

have a nice reading.
05-05-2009, 02:53 PM   #3
Veteran Member
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,685
As someone who has followed many of their posts over the years, I can provide what I *think* is an accurate summary:

- all models can do "dark frame substraction" (aka "slow shutter speed NR") at slow shutter speeds

- the K20D is the only Pentax camera that in fact cannot turn that type of NR *off*

- all recent models provide "high ISO NR" settings in the menu that affect JPEG only

- the K20D appears to perform "some" (albeit not necessarily a lot) of NR even on RAW files at high ISO, even if you've turned the NR option off (like I said, it's only relevant for JPEG). The proof of this is way over my head mathematically, but Oleg and Gordon know what they are doing and seem 100% convinced their mathematical analysis of the RAW data itself demonstrates beyond any shadow of a doubt that this *is* going on.

- as far as I can tell, no evidence of this sort of slight high ISO NR being applied to RAW files has been found in other Pentax cameras, although I'm not sure they decided for sure one way another regarding the K-m/K2000

The actual amount of high ISO NR applied by the K20D to its RAW files does not seem to be of the sort that should be "extremely disappointing". It seems to have no discernible effect on detail. If you're imagining some sort of heavy-handed Neat Image style of NR, that's *not* what they are talking about. Just mathematical evidence that the numbers have been processed slightly.

BTW, after all this extensive analysis of noise levels at different ISO settings (and comparing different types of noise levels too), Gordon ended up buying a K200D for himself as the best bang for the buck, although I haven't seen many posts lately to get a sense if the camera is living up to his own expectations.

Last edited by Marc Sabatella; 05-05-2009 at 03:00 PM.
05-05-2009, 03:11 PM   #4
Site Supporter
Site Supporter
ManuH's Avatar

Join Date: Dec 2007
Location: Montreal
Photos: Gallery | Albums
Posts: 1,249
Original Poster
QuoteOriginally posted by Marc Sabatella Quote
- as far as I can tell, no evidence of this sort of slight high ISO NR being applied to RAW files has been found in other Pentax cameras, although I'm not sure they decided for sure one way another regarding the K-m/K2000

The actual amount of high ISO NR applied by the K20D to its RAW files does not seem to be of the sort that should be "extremely disappointing".
I know about Gordon, I read (not understand...) his posts always with great interest. I know what he said about K20D RAW NR, and yes this is not the kind of heavy-handed NR that Sony used in their A700. But nonetheless it's disapointing (ok maybe not extremely) that you can't turn it off at all. That may explain the strange noise pattern at ISO 3200 and above.

According to DXO, the K200D also uses RAW NR at 800 and above. Maybe not much but enough that its score was equal to the K20D. That was strange as all other tests show the K20D performing better at high ISO.

Now the Nikon D90 figures are also suspect considering this the same sensor as used in the D300 and A700. However, nobody (Gordon did also analysed it) has yet been able to prove it. But the pictures are also strangely somewhat soft...

05-05-2009, 07:58 PM   #5
Veteran Member
Marc Sabatella's Avatar

Join Date: Sep 2006
Location: Denver, CO
Photos: Gallery
Posts: 10,685
QuoteOriginally posted by ManuH Quote
That may explain the strange noise pattern at ISO 3200 and above.
It might, or it might be that it would be even stranger without the NR applied. Whose to say?

Actually, I'm just taking you at your word about strange noise patterns. I don't have a K20D, but have seen some images where noise looks "normal", and others where there is a kind of cross-hatched pattern. Kind of like the infamous VPN many people saw with the K10D. *Occasionally* I'll see something like that when doing extreme push processing on the K200D, but mostly not. So I'm assuming that to some degree, this sort of thing *is* "normal".

QuoteQuote:
According to DXO, the K200D also uses RAW NR at 800 and above.
OK; I can't prove or disprove that. I can only say that others who specifically looked for it didn't see it. Not that it matters to me one way or the other.

QuoteQuote:
Maybe not much but enough that its score was equal to the K20D. That was strange as all other tests show the K20D performing better at high ISO.
I'm convinced that high ISO performance depends on so many variables that you can get a comparison to come out however you want depending on how you test.
05-05-2009, 08:13 PM   #6
Loyal Site Supporter
Loyal Site Supporter
monochrome's Avatar

Join Date: Mar 2008
Location: Working From Home
Photos: Gallery | Albums
Posts: 26,276
????

Four questions
  1. Why does this matter?
  2. Who is Gordon B Good?
  3. Who pays for DxO labs?
  4. Does anyone find the timing interesting, in light of the momentum building for the K-7?
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!
camera, cameras, dslr, iso, k200d, noise, pentax, photography, reduction

Similar Threads
Thread Thread Starter Forum Replies Last Post
Question Posting RAW files on Pentax Forums? jpzk Site Suggestions and Help 7 10-20-2010 11:39 AM
Corrupted Pentax RAW Files wadedesk Pentax Camera and Field Accessories 3 07-09-2009 04:03 AM
Preview Pentax RAW files in Windows??? rsi1986 Digital Processing, Software, and Printing 9 11-03-2008 12:51 AM
Does the Photoshop RAW converter work with Pentax RAW Files? mconder Pentax DSLR Discussion 3 05-15-2008 12:14 PM
card reader corrupting Pentax raw files? Douglas_of_Sweden Pentax DSLR Discussion 9 05-04-2008 01:56 AM



All times are GMT -7. The time now is 11:11 PM. | 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