Histogram...RGB or brightness?

[keithallenlaw]

A little survey here on which way you review your histogram. RGB or
brightness. Most importantly if you answer this which format do you
shoot? Raw or .jpg.

I use the RGB and I sometimes make adjustments in the WB Shift/BKT if I clip
a certain color. But, since I shoot RAW I find this a useless feature. After all,
your seeing a in-camera converted .jpg histogram anyway.

[brian.austin]

Depends on the camera. Some don't show RGB histograms, only exposure.

[keithallenlaw]

Originally Posted by brian.austin

Depends on the camera. Some don't show RGB histograms, only exposure.

Very observant you are. Obviously I meant this for the ones who have this
feature. Anyway, have you had the chance to use this option yourself?

Actually since you brought it up, the one who don't have this option are
welcome to elaborate as well.

[dougsmit]

I use RGB, shoot RAW and find I often reshoot a flower to tame the blown red channel. Yes, the histogram shows the JPG but you have control over the settings for the JPG even though it is not the saved file. How much and what control depends on camera model but setting to a lower saturation and contrast might help if you suffer from false positives of blown highlights.

[Jose]

Brightness, RAW and move the curve to the right carefully not to blow away the highlights.

[PavelOlavich]

Originally Posted by Jose

Brightness, RAW and move the curve to the right carefully not to blow away the highlights.

Is it a crime to blow highlights?

Often one requires some blown highlights in order to expose the subject properly. I don't consider this a bad thing. Often, exposing to not blown any highlights makes for a bad picture.

Until our DSLR's provide human-like DR, this is a challange we all deal with.

[Jose]

There is no crime in blowing highlights...you must do what gives you the image you want. All you are doing is loosing information.

"Often, exposing to not blown any highlights makes for a bad picture." Maybe, but with the miracles of Photoshop one can expose to preserve all the information that is available and then make the image look anyway you please. Once the image is blown, the information is lost.

[jfrancho]

I've already posted some of my thoughts that are related to this in this post: http://www.photocamel.com/forum/198571-post20.html. The in camera is only a general reference, as is the histo in the raw converter. Once the file is converted to an actual 16 bit/channel image format (raw is data, not an image format) I can look at both views and trust that the data I am viewing is accurate.

[jfrancho]

Once the image is blown, the information is lost.

This is true. Though highlight recovery tools in raw converters has come quite a long way, it's better to get it right the first time.

[PavelOlavich]

Originally Posted by Jose

There is no crime in blowing highlights...you must do what gives you the image you want. All you are doing is loosing information.

"Often, exposing to not blown any highlights makes for a bad picture." Maybe, but with the miracles of Photoshop one can expose to preserve all the information that is available and then make the image look anyway you please. Once the image is blown, the information is lost.

True, but why "save" unimportant data at the expense of the subject, especially the shadows on the subject?

Are you suggesting that one should never blow highlights?

To get the most image detail, especially in the shadows, one has no choice but to judiciously blown some highlights, or at the very least expose to the right...raw shooting wise.

[PavelOlavich]

Originally Posted by jfrancho

...raw is data, not an image format...

A raw image is an image format. Sure it's not meant as a result, but one could display an image from it, yea?

[PavelOlavich]

Originally Posted by jfrancho

This is true. Though highlight recovery tools in raw converters has come quite a long way, it's better to get it right the first time.

Once the tone reaches binary value 255, it's gone forever, or in the case or raw, a value of 4,095 (12-bit). Or if in both cases, the value is 0 (zero), then that shadow is gone forever too.

[dougsmit]

Originally Posted by PavelOlavich

A raw image is an image format. Sure it's not meant as a result, but one could display an image from it, yea?

Not really. RAW is a set of values which can be utilized by a conversion program to build an image viewable on screen or saveable in one of the image formats (JPG, TIFF etc.). The same information will not be displayed in exactly the same manner when using different conversion programs even when using default settings. Cameras do not really record images but the sensors produce a series of digital values that approximate the analog world which become images either through an in camera 'engine' guided by 'parameters' or by RAW converters that allow interpretation of the data. No camera is an exact clone of the human eye/brain team; no image format is a perfect mirror of reality. That may be why each of us has our own preferences regarding what happens to light between the click of the shutter and the final result.

[jfrancho]

Originally Posted by PavelOlavich

A raw image is an image format. Sure it's not meant as a result, but one could display an image from it, yea?

No, raw is data and metadata. It does sometimes house an embedded jpeg, but raw in itself is data.

[jfrancho]

Originally Posted by PavelOlavich

Once the tone reaches binary value 255, it's gone forever, or in the case or raw, a value of 4,095 (12-bit). Or if in both cases, the value is 0 (zero), then that shadow is gone forever too.

Glad to see you corrected yourself. Blown/clipped = gone.

[PavelOlavich]

Originally Posted by jfrancho

No, raw is data and metadata. It does sometimes house an embedded jpeg, but raw in itself is data.

Friend not so, raw is data. jpg is data. Tiff is data. Any and all electronic image files are data, as they all are made of binary zeros and ones.

Raw describes an image. Sure it is colorless, color space free, but nonetheless, the raw format is an image format, as you can display an image from it, in the same way that jpg, tiff and all the other formats describe an image.