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<blockquote data-quote="WayneF" data-source="post: 359737" data-attributes="member: 12496">Perhaps unwanted, but an alternative option to consider...The philosophy of Contrast is to make the dark tones darker, and the light tones lighter.&nbsp;&nbsp; This increases visual contrast.&nbsp;&nbsp; Any tonal changes affect color of course.&nbsp; Color often can't stand too much contrast (less is often more, the color is the actual contrast), but grayscale often specifically needs a little something to be quite black and a little to be quite white.The editor tool named Contrast (generally, in all photo editors) are old fashioned simple tools.&nbsp; It works, but I sort of cringe when you mention it.&nbsp; <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile&nbsp; &nbsp; :)" loading="lazy" data-shortname=":)" />&nbsp; If you watch the histogram as you increase Contrast, you see that it is merely pushing data off the right end, and pushing data&nbsp; off the left end, expanding the range to push data off both ends (if you go very far).&nbsp;&nbsp; Equal amounts in both directions.&nbsp; 100 is pretty far.Darks are darker then, and light tones are brighter, it is the idea, but there can be substantial clipping at both ends.&nbsp; Depending on the data, this clipping can be different in each of the RGB channels, so actual color changes can occur.&nbsp; And clipping can cost detail at both ends.&nbsp; Raw is lossless, so you can undo and get it back, but the tool is sort of old fashioned.&nbsp;&nbsp; Assuming ACR&nbsp;&nbsp; (like Lightroom), you have a better choice. &nbsp;The second little menu toolbar icon is a Curve tool.&nbsp; In it, there is a tab called Point.&nbsp; It offers a few preset menus, named Linear, Medium Contrast, Strong Contrast, or Custom. Just to see it once, select Strong Contrast&nbsp; (you can restore Linear).&nbsp;&nbsp; You see a S-Curve. The Curve tool is a response curve, and S-Curve is a very standard tool for contrast.&nbsp; You see in the shape of the S-Curve that it lowers dark tones, and raises bright tones.&nbsp;&nbsp; Darker darks and brighter lights, which is contrast.&nbsp; &nbsp; But it does not clip. You can see that it leaves the 0 and 255 ends alone.&nbsp; This is normally a superior tool.&nbsp;Watch the histogram, and compare histogram action (to the other Linear and then Basic Contrast tool).&nbsp; Don't do both.Or, you can grab the points on the curve, and move them differently, which becomes Custom (any response curve you want).&nbsp;&nbsp; Linear (default) is a straight line response curve, no contrast action at all.I often like to have the Medium S-Curve be default for snapshots (but maybe not often for portraits).More about understanding the general Curve Tool is at&nbsp; <a href="http://www.scantips.com/curve/" target="_blank">Photo Editor Curve Tool</a>&nbsp; &nbsp; (comparing it to Levels)</blockquote>

[QUOTE="WayneF, post: 359737, member: 12496"] Perhaps unwanted, but an alternative option to consider... The philosophy of Contrast is to make the dark tones darker, and the light tones lighter. This increases visual contrast. Any tonal changes affect color of course. Color often can't stand too much contrast (less is often more, the color is the actual contrast), but grayscale often specifically needs a little something to be quite black and a little to be quite white. The editor tool named Contrast (generally, in all photo editors) are old fashioned simple tools. It works, but I sort of cringe when you mention it. :) If you watch the histogram as you increase Contrast, you see that it is merely pushing data off the right end, and pushing data off the left end, expanding the range to push data off both ends (if you go very far). Equal amounts in both directions. 100 is pretty far. Darks are darker then, and light tones are brighter, it is the idea, but there can be substantial clipping at both ends. Depending on the data, this clipping can be different in each of the RGB channels, so actual color changes can occur. And clipping can cost detail at both ends. Raw is lossless, so you can undo and get it back, but the tool is sort of old fashioned. Assuming ACR (like Lightroom), you have a better choice. The second little menu toolbar icon is a Curve tool. In it, there is a tab called Point. It offers a few preset menus, named Linear, Medium Contrast, Strong Contrast, or Custom. Just to see it once, select Strong Contrast (you can restore Linear). You see a S-Curve. The Curve tool is a response curve, and S-Curve is a very standard tool for contrast. You see in the shape of the S-Curve that it lowers dark tones, and raises bright tones. Darker darks and brighter lights, which is contrast. But it does not clip. You can see that it leaves the 0 and 255 ends alone. This is normally a superior tool. Watch the histogram, and compare histogram action (to the other Linear and then Basic Contrast tool). Don't do both. Or, you can grab the points on the curve, and move them differently, which becomes Custom (any response curve you want). Linear (default) is a straight line response curve, no contrast action at all. I often like to have the Medium S-Curve be default for snapshots (but maybe not often for portraits). More about understanding the general Curve Tool is at [url=http://www.scantips.com/curve/]Photo Editor Curve Tool[/url] (comparing it to Levels) [/QUOTE]

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