Photoshop 4

The new artistic potential and control is enormous, but this isn't what's so extraordinary about adjustment layers. Rather it's the fact that their effects can be edited. Simply double-clicking on the name in the layer palette calls up the appropriate adjustment dialog where all settings can be modified. The actual data in the underlying image is completely unaffected by the changes made, so that the effect can be edited any number of times without any degradation to the image quality. This really marks a huge shift in bitmap editing, giving the expert user the power to produce higher-quality, fine-tuned work while giving all users the freedom to experiment. Now if only filters could be applied in the same way.

Another change designed for the professional user who turns to Photoshop everyday, is the ability to automate repeated processes that are essentially macros for Photoshop. By choosing the new command from the Actions palette, specifying a name and then recording your commands as you carry out a task, it's then possible to repeat the same actions at any point in the future simply by hitting the play button. A good example would be if you had a number of scans that you wanted to convert to greyscale, equalise and then sharpen.

For repetitive actions like these the Actions palette is a godsend, particularly as the Batch option allows the same commands to be applied to all the files in a directory. For repro houses, this ability to let the program run basic tasks unattended will save them a fortune. For cases where input remains necessary, it's possible to fine-tune the macro before it's run, so that certain steps can be omitted if they're not appropriate to the current image or the macro can be temporarily paused while the user makes particular refinements.

Apart from this, however, the control is limited. The scripts aren't editable, so there's no way to add conditional intelligence, for example, to save copied sections of a file under an automatically numbered name. Likewise, there's no dialog editor so that there can be no customised interaction with the user. Adobe announced a while back that it was licensing Visual Basic for Applications for a future version of Photoshop. The Actions Palette is not quite it, but it's a taste of things to come.

Electronic watermarks

Photoshop 4's final feature, again pitched squarely at the professional user, is the new watermarking capability brought in from the independent company Digimarc. This addresses the huge problem of protecting the creator's copyright by imperceptibly adding a digital watermark to the image. The theory is that, even from images that have been output and then rescanned, the invisible information will still be readable by the computer. In practice this means that on opening or scanning a watermarked file, a dialog box will pop up to inform you that the image is copyrighted, and it will give you an identifying code. By contacting Digimarc, you'll then be given details of the creator as well as the reproduction costs involved.

Unfortunately, as the feature wasn't implemented in the late beta under review, it's impossible to tell just how reliable the system is. Surprisingly, it's also impossible to tell how popular it will be. A number of the professional photographers you'd expect to be delighted are up in arms. Members of the Digital Imaging Group, for example, have been lobbying for a similar worldwide database to be set up, but as an open standard and on a non-profit making basis. Hopefully, everyone can come to an agreement, but with Adobe's good track record on open standards it would be a pity if it tried to exploit its huge hold on the professional imaging industry.