Forums
New posts
Search forums
What's new
New posts
New media
New media comments
New profile posts
Latest activity
Media
New media
New comments
Search media
Members
Current visitors
New profile posts
Search profile posts
Log in
Register
What's new
Search
Search
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Learning
Computers and Software
PP techniques...
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="WayneF" data-source="post: 359911" data-attributes="member: 12496"><p>Yes, right. The Contrast slider clips seriously at both ends if you apply much at all. True of the "Contrast Tool" in virtually all photo editors, it was one of the first tools invented, and in fact, clipping is often not a bad thing for grayscale images. You see this clipping occur if you watch the histogram as you slide it. This clipping loses detail in those areas. IMO, the tool works better for smaller adjustments than for large ones.</p><p></p><p>The Tone Curve is a more sophisticated method, does not clip, and it also provides a couple of good and useful presets. The S-curve is standard good practice for contrast, esp for color images. And the presets make it be just one click.</p><p></p><p></p><p></p><p>I think you mean Auto Tones. "Tones" threw me, because I use Photoshop instead of Lightroom, and it is the same ACR module, but PS just calls it Auto, I don't see the word Tones there. <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile :)" loading="lazy" data-shortname=":)" /></p><p></p><p>Auto Tones is a automatic system that "analyzes" your image, and automatically "corrects" exposure and contrast and whatever... a few settings change (but not White Balance). It does whatever it thinks the image needs. Often not bad, but it is just dumb automation, and sometimes makes mistakes humans wouldn't make. <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile :)" loading="lazy" data-shortname=":)" /> Sometimes overexposes, IMO. It surely might be helpful, but I rarely use it, preferring to watch my own images. <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile :)" loading="lazy" data-shortname=":)" /> One of my pet peeves is including this Auto Tones in the default preferences, so it is always applied automatically. The problem then is that we never see the real image that came out of the camera, and never know we are screwing up our camera exposures. Then we think we are wonderful photographers, when maybe we're not. <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile :)" loading="lazy" data-shortname=":)" /> Automation is not a way to learn, it's a way to avoid learning. <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile :)" loading="lazy" data-shortname=":)" /></p><p></p><p>Whereas the Tone Curve is just a standard curve tool, which is just a graphical way to adjust tones, mapping input to output values, as we specify by shaping the curve. It can do many more things than Contrast. It can do whatever you shape the curve to do.</p><p></p><p>For example, if you want your image to be brighter now... </p><p></p><p>Photo editors have a Brightness tool, another oldie, that simply adds a numerical constant to all tones, shifting everything higher in the histogram. This clips highlights, and leaves blacks a somewhat lighter gray tone. Not the best tool either.</p><p></p><p>You can use the Exposure slider, which is just the White Point in Levels, and it clips the bright end (stretching the data higher, but leaving the dark end unshifted). However, for images that we want to be lighter, which are dark now, then we probably have no bright end data to clip (any clipping is just areas of non-existent data). But too much Exposure can clip, just like in the camera.</p><p></p><p>Or if the highlights are OK but you just want it brighter... You can just raise the center point of the curve tool, which makes dark and midpoint tones brighter, without any bright end clipping, without much effect at all at the bright end.</p><p></p><p>We can watch the histogram, and generally see the action, and the clipping, etc.</p></blockquote><p></p>
[QUOTE="WayneF, post: 359911, member: 12496"] Yes, right. The Contrast slider clips seriously at both ends if you apply much at all. True of the "Contrast Tool" in virtually all photo editors, it was one of the first tools invented, and in fact, clipping is often not a bad thing for grayscale images. You see this clipping occur if you watch the histogram as you slide it. This clipping loses detail in those areas. IMO, the tool works better for smaller adjustments than for large ones. The Tone Curve is a more sophisticated method, does not clip, and it also provides a couple of good and useful presets. The S-curve is standard good practice for contrast, esp for color images. And the presets make it be just one click. I think you mean Auto Tones. "Tones" threw me, because I use Photoshop instead of Lightroom, and it is the same ACR module, but PS just calls it Auto, I don't see the word Tones there. :) Auto Tones is a automatic system that "analyzes" your image, and automatically "corrects" exposure and contrast and whatever... a few settings change (but not White Balance). It does whatever it thinks the image needs. Often not bad, but it is just dumb automation, and sometimes makes mistakes humans wouldn't make. :) Sometimes overexposes, IMO. It surely might be helpful, but I rarely use it, preferring to watch my own images. :) One of my pet peeves is including this Auto Tones in the default preferences, so it is always applied automatically. The problem then is that we never see the real image that came out of the camera, and never know we are screwing up our camera exposures. Then we think we are wonderful photographers, when maybe we're not. :) Automation is not a way to learn, it's a way to avoid learning. :) Whereas the Tone Curve is just a standard curve tool, which is just a graphical way to adjust tones, mapping input to output values, as we specify by shaping the curve. It can do many more things than Contrast. It can do whatever you shape the curve to do. For example, if you want your image to be brighter now... Photo editors have a Brightness tool, another oldie, that simply adds a numerical constant to all tones, shifting everything higher in the histogram. This clips highlights, and leaves blacks a somewhat lighter gray tone. Not the best tool either. You can use the Exposure slider, which is just the White Point in Levels, and it clips the bright end (stretching the data higher, but leaving the dark end unshifted). However, for images that we want to be lighter, which are dark now, then we probably have no bright end data to clip (any clipping is just areas of non-existent data). But too much Exposure can clip, just like in the camera. Or if the highlights are OK but you just want it brighter... You can just raise the center point of the curve tool, which makes dark and midpoint tones brighter, without any bright end clipping, without much effect at all at the bright end. We can watch the histogram, and generally see the action, and the clipping, etc. [/QUOTE]
Verification
Post reply
Forums
Learning
Computers and Software
PP techniques...
Top
