Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
09-08-2008, 10:14 PM   #1
Veteran Member
FHPhotographer's Avatar

Join Date: Jul 2008
Location: Fountain Hills, AZ
Photos: Gallery | Albums
Posts: 1,298
Matching histogram to RAW data?

I came acorss this site Index of /Photography and the following quote: I recommend setting contrast to its minimum value and using the Adobe RGB color space if the camera supports it. This will help the camera histogram match the underlying RAW data as closely as possible.

I now have my K100D set with Saturation/ Sharpness/Contrast at 0/0/0 in Natural Tone and Adobe RGB , but this site suggests 0/0/-2 to get the histogram to most closely reflect the "real" RAW data...while dpreview goes with -2/+1/0 for best post processing base (I assume that means in RAW).

Does this match your experience?
FHPhotographer

09-08-2008, 11:39 PM   #2
Senior Member




Join Date: Oct 2007
Posts: 241
I prefer the opposite - to up both saturation and contrast in camera so the histogram gives me a buffer. My experience with the K10d says that it will very commonly blow out saturated highlights (esp. reds and yellows in floral images) - and not show up as blown out on the histogram. By the way, this is true even in the RAW data. Those highlights are blown beyond recovery.

I like to ETTR as much as I can so I appreciate the small buffer the increased in-cam contrast gives when viewing my histogram (it doesn't show much). And also it gives me a better idea when I have to "stretch" the DR somehow.

Frank.
09-09-2008, 11:52 AM   #3
Veteran Member
FHPhotographer's Avatar

Join Date: Jul 2008
Location: Fountain Hills, AZ
Photos: Gallery | Albums
Posts: 1,298
Original Poster
a bit confused...

QuoteOriginally posted by Frank Fletcher Quote
I prefer the opposite - to up both saturation and contrast in camera so the histogram gives me a buffer. My experience with the K10d says that it will very commonly blow out saturated highlights (esp. reds and yellows in floral images) - and not show up as blown out on the histogram. By the way, this is true even in the RAW data. Those highlights are blown beyond recovery.

I like to ETTR as much as I can so I appreciate the small buffer the increased in-cam contrast gives when viewing my histogram (it doesn't show much). And also it gives me a better idea when I have to "stretch" the DR somehow.

Frank.
You're saying increase the camera settings to decrease the output (histogram)? And what does ETTR mean?
I'm not sure I follow that,
BHPhotog
09-09-2008, 11:59 AM   #4
Veteran Member
ManuH's Avatar

Join Date: Dec 2007
Location: Montreal
Photos: Gallery | Albums
Posts: 1,209
QuoteOriginally posted by FHPhotographer Quote
And what does ETTR mean?
ETTR is lingo for Expose to the Right (I hate acronyms).

09-09-2008, 12:00 PM   #5
Veteran Member
ManuH's Avatar

Join Date: Dec 2007
Location: Montreal
Photos: Gallery | Albums
Posts: 1,209
QuoteOriginally posted by Frank Fletcher Quote
I prefer the opposite - to up both saturation and contrast in camera so the histogram gives me a buffer. My experience with the K10d says that it will very commonly blow out saturated highlights (esp. reds and yellows in floral images) - and not show up as blown out on the histogram. By the way, this is true even in the RAW data. Those highlights are blown beyond recovery.
Did you know you have the option to display an RGB histogram with the K10D?
09-09-2008, 12:03 PM   #6
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,611
ETTR means "expose to the right"

a digital photography "rule of thumbs" whereby the goal of your image taking should focus primarily on getting your histogram as far to the right as possible even if the image "looks okay" on the screen.

images with histograms that occupy only the first 2 quadrants mean that you are missing out on alot of data.

this does not work for all scenes, but generaly is a good rule to follow, and easily exectued by using the +EV scroller.




as for jpeg settings, first of all, dont read DPreview regarding that, Dpreview reviews camera images based of its JPEG output, which is outright SILLY.


as for what to set it to, i usually shoot monochrome with S and V set to 0 and contrast at its minimum, but i havent run back-to-back tests yet


as for Adobe RBG, remeber this, colour space only matters if you print, and you must have your camera, monitor, printer, and choice of photoprocessing software aligned, hence the option.
09-09-2008, 04:28 PM   #7
Moderator PEG Judges
Kerrowdown's Avatar

Join Date: Aug 2008
Location: Highlands of Scotland.
Photos: Gallery
Posts: 32,662
As you are already aware, the histogram that appears on a compact camera or digital SLR screen is unreliable for anything other than jpeg capture. This is because the histogram you see there is actually based on the camera processed jpeg and is not representative of the true raw capture.

Hence the only way to check the histogram for raw capture is to open the image via a raw processing program such as adobe camera raw or something similar.
09-09-2008, 04:49 PM   #8
Veteran Member
FHPhotographer's Avatar

Join Date: Jul 2008
Location: Fountain Hills, AZ
Photos: Gallery | Albums
Posts: 1,298
Original Poster
This can't be true...

QuoteOriginally posted by kerrowdown Quote
As you are already aware, the histogram that appears on a compact camera or digital SLR screen is unreliable for anything other than jpeg capture. This is because the histogram you see there is actually based on the camera processed jpeg and is not representative of the true raw capture.

Hence the only way to check the histogram for raw capture is to open the image via a raw processing program such as adobe camera raw or something similar.
No, I wasn't aware of that...and I find it hard to believe. You're saying all DSLR camera histograms are unreliable (inaccurate) in RAW? To the point that the only way see the accurate exposure is to load it into a computer and open it ACR et al? That runs counter to everything I've read and been told. Some explanation is in order,
FHPhotographer

09-09-2008, 05:10 PM   #9
Senior Member




Join Date: Oct 2007
Posts: 241
QuoteOriginally posted by ManuH Quote
ETTR is lingo for Expose to the Right (I hate acronyms).
yup. I bet you don't always type out Adobe-Red-Green-Blue though.

How about Digital Single Lens Reflex?

Acronyms can be confusing but useful. Maybe the admins might see about adding a hover-dictionary for acronyms.

QuoteOriginally posted by FHPhotographer Quote
You're saying increase the camera settings to decrease the output (histogram)? And what does ETTR mean?
I'm not sure I follow that,
BHPhotog
ManuH gave you the short-short version.
Gooshin gave you the short version.
One semi-long version can be found here (digitalphotopro.com)
Another longish version is here. (luminous-landscape.com)

Rags Gardner has an interesting rebuttal here. (rags-int-inc.com)


QuoteOriginally posted by ManuH Quote
Did you know you have the option to display an RGB histogram with the K10D?
I did and I do. Thanks.


I get results I like with ETTR. It doesn't suit everybody's workflow.

I shoot RAW ProRGB - developed in RawTherapee, Lightroom or Camera Raw. My experience with the K10D is that when shooting saturated colors, the RAW data can often blow out with little (none) warning from the RGB histogram or blinkies. This is annoying! So I have to watch out for it.

One way to do this is to up the contrast and saturation in the in-cam jpeg settings.

Upping the contrast stretches the histogram - making highlights even lighter and shadows even darker. This effectively pushes the highlight end even more to the right... so when I expose to keep highlights inside of the histogram, I know I have a buffer against highlight clipping.

Upping the saturation is like upping the contrast but for colors. Any primary color (R, G or B) that contributes substantially to a highlight area will be increased in intensity - pushed to the right in the histogram. Any primary color that doesn't contribute substantially gets decreased in intensity. In this case, I am concerned with the right side of the histogram.

For example, if I am shooting a sunflower in full sunlight, Red and Green will be pushed even more to the right on the in-camera histogram while blue will be pushed to the left.

Lastly, note that my K10D screen is tiny...and it isn't color managed... so I don't give a rats-you-know-what (RYKW???) what it looks like in the field.
09-09-2008, 05:23 PM   #10
Veteran Member
ManuH's Avatar

Join Date: Dec 2007
Location: Montreal
Photos: Gallery | Albums
Posts: 1,209
QuoteOriginally posted by Frank Fletcher Quote
yup. I bet you don't always type out Adobe-Red-Green-Blue though.

How about Digital Single Lens Reflex?

Acronyms can be confusing but useful. Maybe the admins might see about adding a hover-dictionary for acronyms.
OK, but I find ETTR OTT, but maybe I'm OT?

QuoteOriginally posted by Frank Fletcher Quote
I shoot RAW ProRGB - developed in RawTherapee, Lightroom or Camera Raw. My experience with the K10D is that when shooting saturated colors, the RAW data can often blow out with little (none) warning from the RGB histogram or blinkies. This is annoying! So I have to watch out for it.
I agree, it's easy to blow a channel, especially shooting flowers and their deep colors. Something should be done by Pentax to display the real raw histogram, not the Joint Photographic Experts Group one ;-)
09-09-2008, 05:37 PM   #11
Senior Member




Join Date: Oct 2007
Posts: 241
QuoteOriginally posted by ManuH Quote
I agree, it's easy to blow a channel, especially shooting flowers and their deep colors. Something should be done by Pentax to display the real raw histogram, not the Joint Photographic Experts Group one ;-)
Haha - that's a good one!
09-09-2008, 06:46 PM   #12
Veteran Member
FHPhotographer's Avatar

Join Date: Jul 2008
Location: Fountain Hills, AZ
Photos: Gallery | Albums
Posts: 1,298
Original Poster
I'm not arguing, but...

QuoteOriginally posted by Frank Fletcher Quote
yup. I bet you don't always type out Adobe-Red-Green-Blue though.
ManuH gave you the short-short version.
Gooshin gave you the short version.
Another longish version is here. (luminous-landscape.com)
Well, this is a curious luminous-landscape cite: "The simple lesson to be learned from this is to bias your exposures so that the histogram is snugged up to the right, but not to the point that the highlights are blown."
So, this guy uses the histogram you're saying isn't accurate? I'm not trying to pick an argument here, it's just that this sound contradictory...

I get results I like with ETTR. It doesn't suit everybody's workflow.
One way to do this is to up the contrast and saturation in the in-cam jpeg settings. Upping the contrast stretches the histogram - making highlights even lighter and shadows even darker.
I thought none of those settings mattered in RAW; are you saying that they do? Again, I'm not disagreeing, just asking...
Lastly, note that my K10D screen is tiny...and it isn't color managed... so I don't give a rats-you-know-what (RYKW???) what it looks like in the field.
Well, I don't have a K10, so I'll take your word for it, but that raises another question... isn't one of the virtues of digital SLR the ability to make adjustments as you're shooting based on the images and changing conditions? You're saying that everything is done in post processing, so you shoot a lot and then see what you've got in the computer using the ACR histogram?
FHPhotog
09-09-2008, 06:52 PM   #13
Ole
Administrator
Ole's Avatar

Join Date: Sep 2006
Location: Copenhagen, Denmark
Photos: Gallery | Albums
Posts: 3,881
QuoteOriginally posted by FHPhotographer Quote
I came acorss this site Index of /Photography and the following quote: I recommend setting contrast to its minimum value and using the Adobe RGB color space if the camera supports it. This will help the camera histogram match the underlying RAW data as closely as possible.

I now have my K100D set with Saturation/ Sharpness/Contrast at 0/0/0 in Natural Tone and Adobe RGB , but this site suggests 0/0/-2 to get the histogram to most closely reflect the "real" RAW data...while dpreview goes with -2/+1/0 for best post processing base (I assume that means in RAW).

Does this match your experience?
FHPhotographer
Just to avoid any misunderstandings - the adjustments which you mention (Saturation/ Sharpness/Contrast) has no effect whatsoever on the RAW files.

Last edited by Ole; 09-11-2008 at 08:59 PM.
09-09-2008, 07:03 PM   #14
Loyal Site Supporter
Canada_Rockies's Avatar

Join Date: Nov 2007
Location: Sparwood, BC, Canada
Photos: Gallery | Albums
Posts: 9,533
QuoteOriginally posted by Ole Quote
The adjustments which you mention (Saturation/ Sharpness/Contrast) has no effect whatsoever on RAW files. I must admit that I don't understand that piece of advice which you quote!
I use the "blinkies" as my warning about blown highlights. I have not had a problem doing that with my k10d, and that tends to support the reviews that suggest that the k10d tends to underexpose slightly so that the highlights are not blown out. I find that as long as I have no red flashing in anything but a specular highlight, that my exposures are very good indeed. I avoid yellow flashing (lost detail in the shadow areas) like the plague. Trying to correct that is what introduces digital noise.
09-09-2008, 07:15 PM   #15
Veteran Member
jeffkrol's Avatar

Join Date: Sep 2006
Location: Wisconsin USA
Photos: Gallery
Posts: 8,435
QuoteOriginally posted by FHPhotographer Quote
No, I wasn't aware of that...and I find it hard to believe. You're saying all DSLR camera histograms are unreliable (inaccurate) in RAW? To the point that the only way see the accurate exposure is to load it into a computer and open it ACR et al? That runs counter to everything I've read and been told. Some explanation is in order,
FHPhotographer
If you think that's intriguing, wait till you find out changing iso is unnecessary....
Re: Sounds wild to me: Nikon D3 - D1 / D700 Forum: Digital Photography Review
Oh and by the way setting your white balance multipliers to 1:1:1 will create histograms close to RAW data.
http://forums.dpreview.com/forums/read.asp?forum=1021&message=22101328
http://forums.dpreview.com/forums/read.asp?forum=1021&message=29013931&q=uniwb&qf=m

Last edited by jeffkrol; 09-09-2008 at 07:22 PM.
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, camera, dslr, histogram, match, photography, rgb, site
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
K7 - colour settings for accurate RAW histogram? cezarL Pentax DSLR Discussion 17 03-18-2010 04:57 PM
RAW+ and histogram question snofox Pentax DSLR Discussion 3 11-13-2009 08:09 PM
Finally, an in-camera Raw Histogram! dlacouture Pentax DSLR Discussion 14 07-31-2009 02:28 PM
iPhoto 7 RAW (DNG) EXIF Data Getting Trashed zagers Pentax DSLR Discussion 7 04-07-2008 06:19 PM
Read ALL the EXIF data in a PEF RAW file or JPG - Freeware application Rickster Photographic Technique 0 07-11-2007 05:15 AM



All times are GMT -7. The time now is 03:49 AM. | 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