Following on from our look at the new correction parameters added into the latest DNG specifications, senior product manager and writer of Adobe’s Lightroom blog, Tom Hogarty, spoke to us about how these correction parameters were chosen and developed:

‘We came up with our own ideas about the kinds of sensor processing and correction factors that might need to be included, then shopped them around various manufacturers to come up with additional suggestions for Opcodes that should be included in the latest specifications. The result is a combination of things that are already being done and some more forward-looking capabilities - things that nobody is using right now.’

‘This process isn’t new,’ he explained: ‘we went through this when we were coming up with the changes we made in the specifications for v1.2. We were aware that the colour model we were using was coming up short for some manufacturers, so we’d come up with a model and speak to a range camera makers to see what they were doing. That ended up turning into the camera profiles.’

However, there’s not a hard line between Adobe’s thinking and manufacturer’s needs, he said: ‘Through our camera profiling work we constantly see what’s going on with sensors and image processing, so you can’t really make the distinction between what we think is needed and what manufacturers are doing, because the two are inseparable.’

‘I’ve heard a lot of people say that these have been brought in for this camera or that specific case but all of these things are valuable across a range of cameras - they can benefit everything from phone cameras to medium format digital backs. The end goal is to ensure the photographer gets the best possible image quality – there’s nothing nefarious going on.’

Nothing about the inclusion of this information in the DNG files compels anyone to make use of it, either. ‘We’ll go ahead and respect these Opcodes,’ he says: ‘but ultimately they are optional.’

Hogarty says he doesn’t see this need to update the specification as a barrier to the DNG format being taken-on as an ISO standard: ‘That’s not a process that happens overnight. We figured that, while the ball is in our court, it made sense to take input from the industry to move the format forward.’