A Genuine Idea?

Where DNGMonochrome is concerned, I think there are some solutions out there now, which can do the same. I'm not even sure if it wasn't already possible to interpolate on just the green channel, when I came up with the idea. I seldom have a genuine idea. I might think I have, but usually I'm proven wrong later on, because I don't like to research my brain waves. I just want to act on them (if they don't involve physical action). Who cares if it already exists!

You might know the feeling.

So, for the next idea, you tell me if it's genuine or not.

What bothered me about DNGMonochrome was the interpolation algorithm. If you followed my struggles from the beginning, you know I experimented a lot with different approaches. All basically under the assumption that it should be easier to just interpolate for monochrome, than it is for color. That assumption turned out to be quite untrue. So indeed: you might not have to bother with false colors, purple fringing or chromatic aberrations as much, but some of this stuff does show up in other shapes or forms to spoil your black & white photo.

There's the maze pattern if the greens are out of balance; there's zipper artifacts on certain algorithms; there's mazing on other algorithms; there's strange patterns that would show up as moire in the color version... but moire we recognize... some weird block pattern in a black and white photo, not really.

Note by the way that all the babble following, is based on 400% to 800% enlargements. The artifacts I'm talking about are not visible at 100% or when you're just flipping through your DNGMonochromed photo album. This is about extreme pixel peeping and has little to do with photography.

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In the current version of DNGMonochrome I finally settled on VNG for the interpolation. VNG (Variable Number of Gradients) produces overall very nice results, especially strong on diagonals and arcs, and it sharpens up quite nicely, but it has at least one flaw: it can produce zipper artifacts on horizontal and/or vertical edges.

And the problem is: you can't really tweak these things (the interpolation algorithms I mean). The more sophisticated algorithms - and even the simpler ones - are usually structured around tight mathematics. A lot of thought was put into them. Just simply changing a bit here or there, or adding a bit there and here, will only lead to a lot of wasted time and frustration (you thought you solved your zippers, only to discover a major mess somewhere else in the same photo - due to your handy work).

What also bothered me was the user interface of DNGMonochrome. Small previews, not a lot of room to navigate, no zooming. That badly needed an improvement.

And I think I overdid it a bit with the denoising and the deblurring and the RGB filters. Loaded it up with too much stuff no one is actually going to use. So that's gone in the coming update (DNGDeblur will also get an update, later on, so you can still deblur the monochrome results).

It's going to be a clean interface, built around a smooth viewer that can zoom up to 800%. And yes of course finally all the new Leica cameras that produce DNGs will be supported (the 262, the 262 M-D, the M10, and maybe some of the new non-M models).

On a side note: I traded in the Leica M-A. I loved the camera and the all mechanical approach, really, but staying abroad for prolonged periods of time and traveling in between, film photography turned out to be non maintainable (or at least a huge bother). It was hard to find film and even harder to have it developed and you have to count per role how often it goes through an airport scanner. For a short holiday fine. In countries where the broken Fuji development machines are staring at you, as a sad reminder of happier days, being pointed at by the store owner - no sorry, no more spare parts: not so much. I switched to the Leica M-D. Almost the same magical experience: click and then you have to wait... but without the additional hassle.

So, I went to work and tried to improve DNGMonochrome. And along the way I got an idea, when I was implementing a few new algorithms (the new DNGMonochrome will give you a choice out of at least four: VNG, AHD, LMMSE and ACP, perhaps more later on).

A bit silly and a bit nerdy (the idea). Probably quite useless. Not fully worked out yet (it's working but I still need to inspect the end result in comparisons). But that's exactly how I like my ideas, because that might mean the idea is genuine!

I will explain the idea in a next post, where I will also try to explain the differences between the algorithms in the new version.