The raw format (.NEF) from my Nikon DSLRs, contains all the image information recorded by the photosites on the sensor inside the camera. It does not incorporate any of the steps required to convert that image into a jpeg: reduction to 8 bits, increase in saturation, application of unsharp masking, etc. When you shoot as in-camera jpegs this raw data is processed by the camera, applying whatever settings you have active at the time the image is made: white balance, saturation, sharpening. A simple jpeg version is usually embedded in the raw file so that software can show a thumbnail of the raw file.
Let's start with the embedded jpeg in my example of a Black-crowned Night-Heron. This is a good representation of what I'd have gotten directly from the camera.
All I've done is reduce the size to 720 pixels on the long side; there's been no saturation, white balance, levels, or sharpening applied here. Its not a bad image, but I know I can "tune it up" for a better presentation.
Open in ACR
When I open this image in ACR, I start out with the following defaults:
The histogram looks pretty good, but shows a tiny spike on the right side that corresponds to the small white area of the heron at the top of the chest directly down from the eye. That's why the triangle in the top right of the histogram panel is red - it indicates that the red channel is overexposed. I'd given this image -2/3rds ev compensation when I took it, but that wasn't quite enough to keep this small area from blowing out (I didn't want to go too dark overall).
Make ACR Adjustments
Here's the same ACR panel after I've made my adjustments for the raw conversion:
Note that the histogram has essentially the same shape, but I've pushed it a bit to the left to fix the small bright area. I've done this by moving the exposure slider to -0.30, and by moving the recovery slider to 32.
I've also "warmed up " the image a little by moving the Temperature slider from 4450 to 4650.
Finally, I've brought out a touch more color by changing the vibrance slider to +17.
Results of Raw Conversion
That's it for ACR. With these adjustments applied the image opens in PS looking like this (a little darker, richer color, less blue in the greens):
My post processing always uses layers, so here's the layer stack I've created to make my final adjustments.
The Background layer at the bottom of the stack is the image directly above. To this I've added a Levels layer, a Hue/Saturation layer, a Curves layer, and a final layer I've labeled "Darken edges."
I've moved the right slider from 255 down to 228 to expand the histogram and lighten the midtones a bit. Since that would blow out the bright areas on the breast of the heron that I recovered in ACR, I've used the mask that was created on the levels layer to block the changes to the heron. I did this by simply painting black on the mask. Layers and Masks are the key to controlling adjustments in PS and essential to understand as soon as possible.
Here's what the levels layer has done.
A little saturation will always bring out more of the color in an image, but it is easy to go too far. I've added 12 points overall.
The results of increasing saturation (on top of the levels changes):
Curves is a great way to add a touch of contrast. This helps define the feather texture and the vegetation. Here I've used the "linear contrast" preset curve which helps the middle tones the most.
The results of boosting the contrast (on top of the levels and saturation):
Now we're almost there. To me, this image is all about the getting a good glimpse of the heron in a daytime roost "hidden" in the trees. So I'd like to emphasize that by subtly darkening the edges of the image. This is an old darkroom trick that keeps the viewer's eye on the subject, instead of wandering off the edges of the image. To do this I made a rectangular selection with a generous feathered edge inside the boundary of the image, and inverted it so I had just the outer edge selected. With the selection active I added a levels layer (it doesn't matter what kind of adjustment you pick here), and clicked "ok" without moving any sliders. I then changed its mode to Multiply and brought the layer opacity way down to about 10-12%.
Here's the final result:
To complete the image:
- flatten all layers
- convert to 8 bit
- crop (I took off a tiny bit on both the left and right)
- resize (I did all my work on the full size image; these examples are all at 720 pixels)
- use Smart Sharpen on the heron
- add my copyright
- save as jpeg
The final jpeg for web posting
And for easy comparison, here's the original embedded jpeg again.
Download this article as a 860 KB PDF