PhotoCamel: Your friendly photo community, with free discussion forums, digital photography reviews, photo sharing, galleries, downloads, blogs, photography contests, and prizes.
Photo of the Week Photo of the Week
 

Go Back   PhotoCamel - Your Friendly Photography Forum > The Photographer > Tutorials

Reply
 
LinkBack Thread Tools Display Modes
Old 10-02-2008   #1
Photocamel Master
 
Benji's Avatar
 
Location: Bluffton, IN
Posts: 5,660
Benji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armor
CamelKarma: 571490
Editing OK?: No
Default PS Technique For Checking Exposure (Portraits)

If you want to check to see if an image is properly exposed in the highlights and the shadows use this Photoshop technique.

Open the image and grab the eyedropper from the tool box, then go to the top of the screen and click on Window then scroll down to Info. A box will appear. Hover the eyedropper over the brightest area of skin (usually a reflection of the main light on the cheek or forehead) and read the "R" reading on the left side of the box. If it is between 236 and 240 the image is properly exposed. If it above 240 it is overexposed. If it is below 236 it is underexposed. There are 32 points in one stop, so if your reading was 225 in the brightest area of skin you are 1/3rd of a stop underexposed (236 minus 11 = 225. One third of 32 is 11.)

To check for underexposure, hover the eyedropper over the darkest shadow that you should have detail in. In a woman with long hair this will be under the ear on the shadow side of the image. This reading should be between 12 and 32. If it is below 12 it is underexposed.

In the example image below, the brightest area was at the black circle on her forehead and it measures 240. The darkest area was under her ear and hair on the shadow side of her face and the area inside the white circle measures 15.

To check this for yourself right click on this image and highlight "Save Picture As" then note where the image was saved to and the name (INFO) then open it up in Photoshop.

Benji

__________________
Members don't see ads in threads. Register for your free account today and become a member of PhotoCamel to open up the site's many benefits and features.
Attached Images
File Type: jpg INFO.jpg (123.7 KB, 3096 views)
__________________
In the end, people appreciate frankness more than flattery. Prov 28:23
Benji is offline   Reply With Quote
Old 10-02-2008   #2
Llama
 
12stones's Avatar
 
Location: Charlotte
Posts: 579
12stones is a name known to all12stones is a name known to all12stones is a name known to all12stones is a name known to all12stones is a name known to all12stones is a name known to all12stones is a name known to all12stones is a name known to all12stones is a name known to all12stones is a name known to all12stones is a name known to all
CamelKarma: 3083
Editing OK?: Ask first
Default Re: PS Technique For Checking Exposure (Portraits)

This is an excellent tool, Benji. Thanks for sharing!
12stones is offline   Reply With Quote
Old 10-02-2008   #3
Photocamel Master
 
Lee4145's Avatar
 
Location: Arizona, USA
Posts: 5,872
Lee4145 has a brilliant futureLee4145 has a brilliant futureLee4145 has a brilliant futureLee4145 has a brilliant futureLee4145 has a brilliant futureLee4145 has a brilliant futureLee4145 has a brilliant futureLee4145 has a brilliant futureLee4145 has a brilliant futureLee4145 has a brilliant futureLee4145 has a brilliant future
CamelKarma: 13097
Editing OK?: No
Default Re: PS Technique For Checking Exposure (Portraits)

Good info Benji.


Quote:
To check this for yourself right click on this image and highlight "Save Picture As" then note where the image was saved to and the name (INFO) then open it up in Photoshop.
To do this without saving it just right click and hit 'copy'.

Then in PS hit ctrl N and enter.
Then ctrl V and you'll have it open in PS ready to look at.
__________________

Project4145







Lee4145 is offline   Reply With Quote
Old 10-02-2008   #4
PhotoCamel Supporter DONATED
Photocamel Master
 
loeee's Avatar
 
Location: California
Posts: 5,134
loeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armorloeee strides over the forum like a knight in shining armor
CamelKarma: 728912
Editing OK?: Yes
Default Re: PS Technique For Checking Exposure (Portraits)

Benji, does this vary at all with different complexions? In a group with "brown" people and "pink" people, will this still work?
__________________

"Do Justly, Love Mercy, Walk Humbly." Micah

Canon

Ancora Imparo
loeee is offline   Reply With Quote
Old 10-02-2008   #5
Guanaco
 
Posts: 292
TAFNAP is a jewel in the roughTAFNAP is a jewel in the roughTAFNAP is a jewel in the roughTAFNAP is a jewel in the rough
CamelKarma: 334
Editing OK?: Yes
Default Re: PS Technique For Checking Exposure (Portraits)

Thank you Benji, I knew I read this before for some reason I thought it was much more complex. But this will work perfect thanks again for your patience and guidance.
TAFNAP is offline   Reply With Quote
Old 10-02-2008   #6
gsk
PhotoCamel Supporter DONATED
Bactrian
 
gsk's Avatar
 
Location: FL
Posts: 1,940
gsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armorgsk strides over the forum like a knight in shining armor
CamelKarma: 124499
Editing OK?: Yes
Default Re: PS Technique For Checking Exposure (Portraits)

Thank you... How can you correct it in Photoshop without going into ACR or Lightroom. Sorry for the stupid question.
__________________
Critiques and comments always welcomed... Gary
gsk is offline   Reply With Quote
Old 10-03-2008   #7
Photocamel Master
 
Benji's Avatar
 
Location: Bluffton, IN
Posts: 5,660
Benji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armor
CamelKarma: 571490
Editing OK?: No
Default Re: PS Technique For Checking Exposure (Portraits)

Quote:
Originally Posted by loeee View Post
Benji, does this vary at all with different complexions? In a group with "brown" people and "pink" people, will this still work?
"Pink" people are the same. Brown people is a little different. We still need the 240 in the highlights, but in dark skinned people we should light them so light reflections are used to show the form and contours of the face not shadows. A dark shadow on dark skin only makes the skin darker which will not show form and contour.

Benji
__________________
In the end, people appreciate frankness more than flattery. Prov 28:23
Benji is offline   Reply With Quote
Old 10-03-2008   #8
Photocamel Master
 
Benji's Avatar
 
Location: Bluffton, IN
Posts: 5,660
Benji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armorBenji strides over the forum like a knight in shining armor
CamelKarma: 571490
Editing OK?: No
Default Re: PS Technique For Checking Exposure (Portraits)

Quote:
Originally Posted by gsk View Post
Thank you... How can you correct it in Photoshop without going into ACR or Lightroom. Sorry for the stupid question.
While I'm not sure, I don't believe you can. You can make the image appear to be properly exposed by using levels and curves, but an improperly exposed image will never look as "correct" as one that was properly exposed to begin with (or at least on photographic paper.) You Photoshop experts reading this may want to correct me on this. (Of course I'm not talking about 1/3rd of a stop corrections in Photoshop but rather 3 stop corrections.)

I shoot RAW and use a hand held meter so I very very seldom screw up so badly that I need to make huge corrections in ACR, and I NEVER make exposure corrections in Photoshop, so I'm hardly an expert. All of my old photography teachers touted the same mantra; "get it right in the camera" so that is what I still do.

Benji
__________________
In the end, people appreciate frankness more than flattery. Prov 28:23
Benji is offline   Reply With Quote
Old 11-01-2008   #9
Bactrian
 
Not4wood's Avatar
 
Location: back home from France, in NYC
Posts: 2,297
Not4wood is a splendid one to beholdNot4wood is a splendid one to beholdNot4wood is a splendid one to beholdNot4wood is a splendid one to beholdNot4wood is a splendid one to beholdNot4wood is a splendid one to beholdNot4wood is a splendid one to beholdNot4wood is a splendid one to beholdNot4wood is a splendid one to beholdNot4wood is a splendid one to beholdNot4wood is a splendid one to behold
CamelKarma: 3876
Editing OK?: Ask first
Default Re: PS Technique For Checking Exposure (Portraits)

Great explanation, Benji.

On the sample shot, if your exposure in the numbers is correct why does the image appear slightly too Dense? Or is it my Monitor?

I posted a couple of Portraits in the Thread about the Noise and one of them is slightly Dense as well but the whites of her eyes are bright and theres plenty of detail as well.
__________________
Mark G
Not4wood
My Flickr Portfolio: http://www.flickr.com/photos/30920268@N06/show/

Nikon D700
Nikon D80 w/Kit 18-135
Nikon 70-300 VR f:4.5-5.6
Nikon 60mm f:2.8 Macro
Sigma 24-70 f:2.8 DG DF Aspherical
Old Vivitar 283, Nikon SB900
Manfrotto Tripod 055XB w/Manfrotto 486 RC2 Ball Head
Not4wood is offline   Reply With Quote
Old 11-01-2008   #10
F1 Camel
 
blumesan's Avatar
 
Posts: 2,980
blumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armorblumesan strides over the forum like a knight in shining armor
CamelKarma: 661924
Editing OK?: Yes
Default Re: PS Technique For Checking Exposure (Portraits)

Quote:
Originally Posted by Benji View Post
There are 32 points in one stop, so if your reading was 225 in the brightest area of skin you are 1/3rd of a stop underexposed (236 minus 11 = 225. One third of 32 is 11.)
Benji
Benji-
I certainly am not qualified to question the method you propose to determine if an image is properly exposed. However I must question your method of converting the measured (eyedropper) readings into STOPS. Assuming the 0-255 scale covers 8 stops, the stops are not equally divided into eight intervals of 32 points each. The increment in stops is based on a logarithmic scale. One full stop below 255 would therefore show a value of 128. A reading of 225 would thus compute to 0.186 (~1/6) stop underexposure. A 1/3 stop underexposure would give a value of 203. [ 2^(8.0 - 0.333) ]


__________________
Members don't see ads in threads. Register for your free account today and become a member of PhotoCamel to open up the site's many benefits and features.
__________________
My Gallery
blumesan is offline   Reply With Quote
Reply

« PhotoCamel - Your Friendly Photography Forum > The Photographer > Tutorials »


Share this topic:

Thread Tools
Display Modes

Similar Threads
Thread Thread Starter Forum Replies Last Post
Porting macro technique to portraits Neutron Portraits 7 09-09-2008 10:32 PM
Checking in ... Dee711 Introduce Yourself 5 03-02-2008 07:38 PM
Metering and exposure in portraits ciaran Tutorials 4 11-13-2007 03:57 AM
Checking me Out Fusion Landscape & Travel 8 08-12-2007 12:57 PM