Adobe Photoshop CS5 for Photographers - Martin Evening [168]
Big data
The Photoshop, PDF and TIFF formats all support ‘big data’. This means that if any of the layered image data extends beyond the confines of the canvas boundary, it is still saved as part of the image when you save it, even though it is no longer visible. If you have layers in your image that extend outside the bounds of the canvas, you can expand the canvas to reveal all of the big data by choosing Image Reveal All. Remember though, you will only be able to reveal the big data again providing you have saved the image using the PSD, PDF or TIFF format. Also, when you crop an image that contains normal, non-flattened layers (see sidebar), you are given the option to delete or hide the layered big data by selecting either of these radio buttons in the modal crop Options bar (see Figure 5.69).
Figure 5.69 The cropped version of this picture contains several layers which when expanded using the Image Reveal All command show all the hidden ‘big data’ that extends outside of the cropped view. The Hide option in the crop tool options allows you to preserve the pixels that fall outside the selected crop area instead of deleting them. Note also how the Background layer has been converted to a normal Photoshop layer (Layer 0). This is essential if you wish to preserve all the information on this layer as big data.Client: Rainbow Room. Model: Nicky Felbert @ MOT.
Background layers and big data
If your image contains a Background layer and you want to preserve the data on this layer after making a ‘hide’ crop, you must first double-click the Background layer to promote it to a normal layer. If you don't take this step you will still end up deleting everything on this layer when you crop.
Chapter 6. Black and White
I was eleven years old when I first got into photography. My first darkroom was kept under the stairs of our house and, like most other budding amateurs, my early experiments were all done in black and white. Back then, very few amateur photographers were competent enough to know how to process color, so black and white was all that most of us could manage to work with. For me, there has always been something rather special about black and white photography and digital imaging has done nothing to diminish this. If anything, I would say that the quality of capture from the latest digital cameras, coupled with the processing expertise of Photoshop, and improvements in inkjet printing have now made black and white photography an even more exciting avenue to explore.
Converting color to black and white
The most important tip here is to always shoot in color. Whether you shoot film or shoot digitally, you are far better off capturing a scene in full color and using Camera Raw or Photoshop to carry out the color to mono conversion. Although having said that, you do need to use the most appropriate conversion methods to get the best black and white photographs from your color files.
Black and white film conversions
Traditional black and white film emulsions all differ slightly in the way they respond to different portions of the visual spectrum (as well as the colors we can't see). This is partly what gives emulsion films their ‘signature’ qualities. So in a way, you could say that film also uses standard formulas for converting color to black and white, and that these too are like rigid grayscale conversions. You may also be familiar with the concept of using strong colored filters over the lens when shooting with black and white film, and how this technique can be used to emphasize the contrast