Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-28-2016, 06:20 AM - 4 Likes   #1
Pentaxian




Join Date: Dec 2011
Posts: 1,154
Adobe Nonsense Baseline Exposure Compensation for K-1

Today I shot a Canon 5D Mark III side by side with a Pentax K-1. Same exposure settings, same subject etc.

First I had a look at them in RawDigger to see how the metering and Raws differ. Basically pretty much the same, with the K-1 metering a tiny 1/4 stop more agressively moving the histogram to the right (kind of silly given that Canon sensor really need ETTR, not Sony sensors). Same headroom in the lights.

Then I imported them into lightroom and suddenly the K-1 pictures looked unnaturally dark compared to the Canon ones. On average the K-1 files neededa exposure adjustment of about +2/3.

Wondering how that could be I looked at Adobe's hidden exposure compensation levels in the raw metadata after import into LR and there we have the culprit: Exif:Baseline Exporsure is...
Canon 5D3: +0,25 EV
Pentax K-1: -0,5 EV

This nonsense deliberate (hidden) change by the Adobe software gives the impression K-1 images are underexposed, but they clearly are not.

If you react on this by dialing in ExpComp +2/3 in your camera you are creating more blown highlights as now you force the camera to overexpose. No wonder there still exists the myth, that Canon cameras offer more room in the highlights.

If you do not react on this, images appear too dark in lightroom which is visually not really appealing. Users now must manually correct it and wonder "why the camera doesnt meter better". Which is not the case.
Most casual users are simply unaware of what LR/PS does secretly.

I would say Adobe needs to do their homework.

06-28-2016, 06:39 AM   #2
Lens Buying Addict
monochrome's Avatar

Join Date: Mar 2008
Location: Kirkwood (St. Louis) MO
Photos: Gallery | Albums
Posts: 19,491
^^ Adobe needs to do their homework, or . . . .

Ricoh needs to spend some money and supply Adobe the data to create an accurate camera profile.

Last edited by monochrome; 06-28-2016 at 07:40 AM.
06-28-2016, 06:51 AM   #3
Pentaxian
LensBeginner's Avatar

Join Date: Sep 2014
Photos: Albums
Posts: 2,490
QuoteOriginally posted by monochrome Quote
^^ Adobe needs to do their homoework, or . . . .

Ricoh needs to spend some money and supply Adobe the data to create an accurate camera profile.
Do you mean "money" as in "money to supply Adobe with" or "money to Adobe and supply them with"?
06-28-2016, 06:54 AM   #4
Senior Member




Join Date: Feb 2016
Posts: 104
Adobe are not alone in applying baseline exposure compensation at least from my last look into this topic.

From memory others such as DxO and (I think) capture one also do this.

Apart from the baseline exposure compensation a curve is also added to brighten the image (in Process 2012). So it is possible that if you do go by the look of the image on screen of your raw converter of choice that you could think that you were overexposing by potentially up to a +2EV (baseline + brightening curve) and of course if adjusting exposure in camera to compensate in reality you would be underexposing - or perhaps more correctly giving less than optimal exposure. In cases where the baseline exposure is usually negative (Pentax?) the effect is perhaps less dramatic due to the hidden curve correction to make the image look good/acceptable on screen.

Due to the fact that Adobe and others produce raw converters for many cameras from nearly all manufacturers there is a reason for this behavior and quoting (I think Eric Chan):
In order to have common controls such as Exposure compensation behave the same way across the different cameras, Camera Raw applies a baseline exposure compensation that varies from model to model in order to get them all to behave similarly when the exposure compensation control is set to its default value of zero.

The only way to view the raw data AFAIK (after some slight application manipulation) is to view in an editor that does not apply any compensation e.g. RawTherapee or in a program such as RawDigger or FastRaw viewer.

You can of course make your own camera profile quite easily and negate both the hidden baseline exposure compensation and any hidden Adobe curve manipulations.

Still I agree it would be good for users to be aware of what is happening under the hood

EDIT: Although not a user of Digital Camera Utility (SilkyPix?) it seems to me that they do the same i.e. apply hidden correction.


Last edited by TonyW; 06-28-2016 at 07:06 AM.
06-28-2016, 06:55 AM   #5
Pentaxian




Join Date: Jul 2013
Posts: 1,457
Thank You for Posting this.....to me its very helpful knowing this and now I can deal with it.
06-28-2016, 07:06 AM   #6
Site Supporter
enoeske's Avatar

Join Date: Jul 2009
Location: Surprise, Az
Photos: Gallery
Posts: 1,888
QuoteOriginally posted by beholder3 Quote
Today I shot a Canon 5D Mark III side by side with a Pentax K-1. Same exposure settings, same subject etc.

First I had a look at them in RawDigger to see how the metering and Raws differ. Basically pretty much the same, with the K-1 metering a tiny 1/4 stop more agressively moving the histogram to the right (kind of silly given that Canon sensor really need ETTR, not Sony sensors). Same headroom in the lights.

Then I imported them into lightroom and suddenly the K-1 pictures looked unnaturally dark compared to the Canon ones. On average the K-1 files neededa exposure adjustment of about +2/3.

Wondering how that could be I looked at Adobe's hidden exposure compensation levels in the raw metadata after import into LR and there we have the culprit: Exif:Baseline Exporsure is...
Canon 5D3: +0,25 EV
Pentax K-1: -0,5 EV

This nonsense deliberate (hidden) change by the Adobe software gives the impression K-1 images are underexposed, but they clearly are not.

If you react on this by dialing in ExpComp +2/3 in your camera you are creating more blown highlights as now you force the camera to overexpose. No wonder there still exists the myth, that Canon cameras offer more room in the highlights.

If you do not react on this, images appear too dark in lightroom which is visually not really appealing. Users now must manually correct it and wonder "why the camera doesnt meter better". Which is not the case.
Most casual users are simply unaware of what LR/PS does secretly.

I would say Adobe needs to do their homework.
Do you have highlight protection on?
06-28-2016, 07:21 AM   #7
Pentaxian




Join Date: Dec 2011
Posts: 1,154
Original Poster
QuoteOriginally posted by enoeske Quote
Do you have highlight protection on?
I always have it on Auto in the camera, but in case of the image file I am discussing here, it did not kick in (still ISO 100).

I just adjusted my K-1 .dcp camera profiles to counter the effect and now am quite happy with the results I am seeing upon loading in LR. Much more so than before.

My most liked profile now contains the following ingredients:
a) colorchecker based profile using two extreme color temperatures
b) Anti-Baseline Exposure compensation curve adjustment
c) add a tiny contrast S-curve enhancement to my liking
d) correct the red color magenta tint and oversaturation that can appear on really red subjects
06-28-2016, 07:41 AM   #8
Loyal Site Supporter
Bruce Clark's Avatar

Join Date: Mar 2010
Location: Brookfield, Victoria
Photos: Gallery | Albums
Posts: 3,702
Can this controlled by the default develop settings in Preferences ie. "Make defaults specific to camera serial no" ?

06-28-2016, 07:53 AM   #9
Pentaxian




Join Date: Apr 2007
Location: Romania
Posts: 8,425
QuoteOriginally posted by monochrome Quote
^^ Adobe needs to do their homework, or . . . .

Ricoh needs to spend some money and supply Adobe the data to create an accurate camera profile.
Which should be done in a luxury cruise in Caribbean?
06-28-2016, 08:04 AM   #10
Pentaxian




Join Date: Dec 2011
Posts: 1,154
Original Poster
QuoteOriginally posted by TonyW Quote
In order to have common controls such as Exposure compensation behave the same way across the different cameras, Camera Raw applies a baseline exposure compensation that varies from model to model in order to get them all to behave similarly when the exposure compensation control is set to its default value of zero.
While I could accept that they want to level the starting situation, the scenario we now have here is exactly the opposite:
The starting look and histogram situation in LR is not made more similar across two cameras using the hidden adjustments, but it is made more different.
06-28-2016, 09:03 AM   #11
Senior Member




Join Date: Feb 2016
Posts: 104
QuoteOriginally posted by beholder3 Quote
While I could accept that they want to level the starting situation, the scenario we now have here is exactly the opposite:
The starting look and histogram situation in LR is not made more similar across two cameras using the hidden adjustments, but it is made more different.
If you only subtract baseline exposure you will only be part way there toward seeing what your camera produces.

Ideally you should be also change to Process version 2010 and taking the sliders to zero. Default are Blacks = 5, Brightness +50, Contrast +25 - reduce all these to 0.00 and switch back to Process Version 2012 and look at the sliders.

You should see the values applied between Proc 2010 to Proc. 2012 i.e Exposure = -1.00, Contrast = -33, Blacks = +25. If you now subtract your baseline exposure calculation you should see a very similar presentation of the image data between RawDigger, FastRaw Viewer and Raw Therapee at least as far as density and contrast go.

Worth bearing in mind that initial conversion of raw data is somewhat subjective and what one person views as an acceptable starting point may well differ from another.

In general it appears Adobe have chosen to present an image from each camera raw data that represents a reasonable starting point (at least to them) relating to colour, contrast and brightness with Adobe Standard profile. With some cameras Nikon, Canon they have chosen to offer settings that mimic the look of the presets e.g. Vivid, Camera Neutral etc. and from what I have seen with Nikon have done a very good job. Bearing in mind that neither may be accurate or even desirable renditions of the scene and of course these settings are really only relevant to JPEG (mimicking what is seen on the limited camera LCD)

---------- Post added 06-28-16 at 09:07 AM ----------

QuoteOriginally posted by Bruce Clark Quote
Can this controlled by the default develop settings in Preferences ie. "Make defaults specific to camera serial no" ?
Yes they can but unless you create your own profile the settings will not show as zero defaults but reflect the removal of the Adobe baseline and brightness settings. Baseline exposure compensation may vary with ISO used so should be checked.

Last edited by TonyW; 06-28-2016 at 09:09 AM.
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!
adobe, adobe nonsense baseline, brightness, camera, canon, contrast, data, default, defaults, dslr, exposure, full frame, full-frame, highlights, k-1, k1, pentax k-1, settings, users, wonder
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
exposure compensation dubsider Photographic Technique 7 12-10-2014 03:43 PM
Long exposure / provia 200 : how to know the good exposure compensation ? aurele Pentax Film SLR Discussion 3 02-18-2012 06:58 PM
Camera exposure compensation vs flash compensation raider Photographic Technique 4 09-29-2011 05:02 PM
Exposure Compensation for a manual lens Vantage-Point Pentax SLR Lens Discussion 7 08-05-2011 07:04 PM
K10D & Metz 58-AF-1. Fast flash exposure compensation? kolouch Pentax DSLR Discussion 2 01-02-2009 05:37 AM



All times are GMT -7. The time now is 09:24 AM. | See also: NikonForums.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