Updated: Sep 20, 2020
I'm using this photo to demonstrate how I take an image that is unacceptably grainy when blown up to over three times its original size and transform it into a version that is tolerable at that size. This is the famous "Floating Flower Market" in Amsterdam. When this pic was taken, I was sitting at a patio table at my favourite cafe, crammed in as close to the building as possible (thus with maximum awning coverage), and being generally pleased with the day and amazed by the sudden intensity of this storm in equal measure. The storm really was something. The morning started out only partly cloudy, but rapidly changed course with the clouds thickening, darkening, and finally adopting a peculiar dark grey vertical flatness tinged with yellow. When it hit, the storm was torrential but lacking any wind, which was why sitting outside in it under cover was so entertaining and tolerable.
The couple pictured here are seeking shelter, clearly on behalf of the guy in his suit; she looks prepared for it. The locals, of course, saw it coming a mile away and all had sensibly brought umbrellas.
I draw your attention to two details in this photo to demonstrate just how heavy this rain was. First, notice the streams coming off the awnings. Substantial. Second, look for the white mist at ground level at the extreme right. That's rain bounce, and I'm guessing it was around 18 inches or so high. That's heavy, intense rain.
I like this photo a lot for its slice-of-time narrative, its setting, its colour and composition. I really enjoy the contrast between the vibrancy of the colours and organic textures in the shop against the linear desaturation of the further buildings. I love the expressions on their faces. They both know I am taking their picture. He's smiling a bit in what I interpret to be a slightly embarrassed admission that he was unprepared for this storm, while she seems unimpressed with the situation; a nice contrast between them.
This was the first photo I uploaded to Flickr, back in the day, and has long been one of my contributions to the Creative Commons. A very talented painter named Patricia, from Australia, painted a water colour version (pictured right) and sent me a couple of full-sized gliclees of it, which was very nice of her. She decided to remove the guy, which was an interesting choice. I love those awning rivulets a lot. Just very cool overall, and as far as I know the only time something like this has happened to me.
Unfortunately, I did not do what I would normally do in this type of situation, which is take multiple photos for safety. I only took one, this one, and it's fair to say that it has one major technical issue in that is has just a little bit of hand-jiggle motion blur, always a potential problem when using a longer exposure. Below is the original, unfiltered, unprocessed, out-of-the-camera image:
When depicted at this scale, the photo looks pretty good. Good saturation, acceptably focused. Zooming in provides more information:
The above is a detail of the image scaled up to 9000 pixels wide from its original 2500 or so. It's grainy. The motion blur is obvious on light-coloured things. Not great. In fact, completely unacceptable for print at this size. If this was printed at a size to cover a comforter, for example, those flaws would be right in your face. Literally. To fix this, I apply a number of steps that produce an image that still reads as a photograph at a bit of distance and is reasonably crisp (and stylistically interesting) very close up. All of this is done with Gimp, as I still haven't gotten off of my ass and paid for Photoshop.
The first thing to do is create a duplicate layer (always have the original on the bottom as a safety) and apply some blur to it. I like Mean Curvature Blur because it has an organic kind of multi-directionality and a way of maintaining some sharpness along some edges. Above is the detail with a moderate amount of Mean Curvature Blur, enough to smooth out some of the graininess while not obliterating structure. We need some level of fine-grained structure for the next step, which is applying a Cartoon filter. So, create a duplicate of the blurred layer, and use Cartoon on it. I like the "legacy" version of this filter because you get a preview window. You can control how much and how dense the filter is, and I usually start with the threshold quite low, as seen below, because it outlines most of the detail. The downside is that it also outlines any remaining graininess.
Start manipulating the layer mode of that cartooned layer. Modes like "Darken Only" retain all that very dark cartooning while making other colours more or less transparent. The process then becomes a kind of juggling, with amount/level of cartooning on upper layers on one hand, amount of blurring on lower layers on the other, and various layer modes on the third hand. Below is what I finally settled on :
The final steps are a small amount of overall Curvature Blurring, and a smidge of sharpening. I like to think of this process as a "Stained Glass" filter. It produced soft blocks of colour superimposed by a black(ish) top, detail layer. This process works because it completely translates and re-renders the image while at the same time preserving its structure. Gimp has very few filter options that allow this, so I'm pretty much stuck with this method until such time as I get Photoshop. PS has many filters that enable this kind of thing.
Here's a better view of Patricia's painting:
Makes me happy. :-)