Moving on to Exposure versus Brightness. There's a section in the Bruce Frazer book about this very topic, and IIRC he demonstrates the difference pretty well. In his example, boosting Exposure keeps more detail in the brightest highlights, while boosting Brightness starts to push the midtones into the highlights and reduces highlight detail.
True. Brightness and Exposure are just not the same. Exposure moves the entire histogram to the right or the left. It means that the distance between pixels values doesn't change (until you start clipping of course). Brightness OTOH only pushes up the midtones, and because the highlights are not moved at the same time, you do compress the distance between them.
Thank you, Ken, that's what I was trying to get at.
Johan, I have to disagree with you slightly. The Exposure control doesn't just move the histogram; that's a bit too simplistic an explanation.
From what I can see (and have verified experimentally) the Exposure slider multiplies values in linear space, before tone curves are applied. Seek out my post where I took photos of the same scene at 4 different f/stops and used the Exposure slider to normalize them.
However, what you (and Kevin and Ken above) are saying is correct, the Brightness and Contrast controls seek to preserve highlights and shadows by trying to avoid clipping.
Now, last but not least, the Brightness and Contrast controls in Photoshop CS3 proper actually do this TOO, which represents a change from prior versions. They do provide a legacy checkbox to allow you to clip if you want to, which supports existing Photoshop actions that rely upon this.
You make some good points, Noel. I'm using CS2 and ACR 3.7, but I noticed a little bit of noise in background areas of some photos I was playing around with recently. When I checked my default settings in ACR, I remembered that I had sharpening set to 25, which is way too much for a default. I had saved the defaults when working with a group of underexposed photos a few weeks ago, and then forgot to reset the sharpening to a lower arount.
After playing around with it for a while, I concluded that it is best to convert the raw photo with 0 sharpening in most cases. (too bad we can't use layer masks in ACR and selectively sharpen parts of the photo).
I'm bummed that ACR 4.1 is not compatible with CS2. I was all excited when I read about all the ACR 4.1 improvements on the Adobe website, only to learn that I can't use it unless I upgrade to CS3. I wasn't planning to do that right now, but the new raw converter tempts me.
White Balance so easy, even our 5 year old can do it.- Melissa Strickland
I notice that you have the contrast default set at +25. I have found that the results are more to my taste by setting this to zero along with almost everything else (like you), then, when I reset the Blacks slider to move the blacks down to just before they start clipping the resulting contrast is generally just about right without using the contrast slider at all.
The only other place I use different settings is on the sharpening… I leave it set at 15, 1.0, 25, which seems to be rougly the equivalent to Smart Sharpen values of 50%, 0.6 pixels. I do this so won't have to fiddle with this all the time in Lightroom, which is where I process most of my photos.
BTW, the only way I have found to set the defaults in LR is in ACR… which is fine, I like one-stop-shopping.
White Balance so easy, even our 5 year old can do it.- Melissa Strickland
I cannot disagree too much with your "default" settings. They are quite similar to mine. I also use no sharpening, but do it in the 'Camera Raw preferences' by selecting "For Preview only". This allows some sharpening will viewing the camera raw image or the results in Bridge, but does not apply any sharpening on conversion to PSD.
I do have a question on the following point....
Quote:
Originally Posted by Noel_Carboni
>>> Set my color space to sRGB, image size to one notch up from the camera's native sensor size, and the bit depth to 16 bits per channel.
Unless you are converting to only view on your monitor or the web, why are you choosing sRGB at this point? For printing (with color managed printers) you would be better served using aRGB...and you can always convert to sRGB (do it before changing mode to 8 bit). Some would argue that Prophoto would be better, as you can lose some (small edge) of the possible printer colors, but that gets into a "religious war", which is not worth getting into.
The other is your increasing the image size. I do not know the exact process that Adobe does in ACR to "upsize", but I suspect (I'm willing to be enlightened) that it is not much different from the upsize/resampling done in PS. Each time you resample you are going to lose some image quality. I think you sould do it once...when you need it....and if it is a big change, with something better that PS' bicubic algorithms.
One other point you may want to consider for you "defaults". That is 'ACR Calibration'. If you are interested Google "acr calibration rags". I have used his process for my 5D and have been very happy.
John
__________________ John Schwaller
White Balance so easy, even our 5 year old can do it.- Melissa Strickland
Linear Mode
