A tool that measures the tonality of a point (part) of a photo?

[New Daddy]

[I'm not knowledgeable in this area, so I may not be phrasing my question properly.]

My objective: I'm now fairly confident with ambient metering. But TTL flash metering is such a mystery. (I think it is for many people across different systems.) So what I'd like to do is reverse-engineer why the TTL flash meter chose the exposure that it chose by checking the exposure of my subject. For example, if my daughter's face generally has zone 5 tone when properly exposed but the "dropper" measures it at zone 4, I'll know that the TTL flash underexposed it by a stop. Then I'll have to figure out why the TTL underexposed my daughter's face by a stop. Without such calculation, it's hard to estimate how off the TTL flash metering was. Histogram, of course, is of no help, obviously.

Is there a software/app/tool within an app that measures the tonality of a given part or point in a photo? With the "dropper" tool in Lightroom, you can get the RGB number of any point in a photo. I'm not interested in the RGB number. I'm just interested in the tonality, as if I'm spot metering that point/part.

[dje]

[I'm not knowledgeable in this area, so I may not be phrasing my question properly.]

My objective: I'm now fairly confident with ambient metering. But TTL flash metering is such a mystery. (I think it is for many people across different systems.) So what I'd like to do is reverse-engineer why the TTL flash meter chose the exposure that it chose by checking the exposure of my subject. For example, if my daughter's face generally has zone 5 tone when properly exposed but the "dropper" measures it at zone 4, I'll know that the TTL flash underexposed it by a stop. Then I'll have to figure out why the TTL underexposed my daughter's face by a stop. Without such calculation, it's hard to estimate how off the TTL flash metering was. Histogram, of course, is of no help, obviously.

Is there a software/app/tool within an app that measures the tonality of a given part or point in a photo? With the "dropper" tool in Lightroom, you can get the RGB number of any point in a photo. I'm not interested in the RGB number. I'm just interested in the tonality, as if I'm spot metering that point/part.

Hi Rick

If by tonality you are referring to the zone system used in B&W photography you can do this with the Nik plug-in Silver Efex Pro. It has a Loupe/Histogram display with zones 0-10 shown below and you can select one of these zones and see what areas of the image have this range of tones.

Nik plug-ins can be used with PS or Lightroom and probably a few other editors.

Dave

[Polar01]

Rick: as Dave stated usually the Zone is used more for B&W, however came across a article about using The Zone method in colour photography. I go back to it every now and then to reread it, to keep it in my mind as I am trying to visualize what the image will look like in print before capture. Below is the link at Pictureline:

http://www.pictureline.com/blog/why-...r-photography/

Cheers: Allan