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To take a photo, the ideal is for the light to be behind you. We know that this is not always possible: taking a picture of your dog, when he is being adorable, but with the sun behind him, or your friends goofing around at sunset or sunrise. We have all been there. That photo may not be a total waste after all. In a recent discussion on black-and-white photography, the discussion on applications, like Snapseed’s (- not picking on Snapseed, it is just the most well-known in our circle) ability, or inability, to make black-and-white photos look real, came up.
Pour prendre une photo, l'idéal est d'avoir la lumière derrière vous. Nous savons que ce n'est pas toujours possible : la photographie de votre chien, quand il est adorable, mais avec le soleil derrière lui, ou de vos amis s'amusant au coucher ou au lever du soleil. Nous avons tous eu ça. Cette photo n'est peut-être finalement pas à jeter.
Dans un récent échange sur de la photographie en noir-et-blanc, la discussion est venue sur les applications, comme la capacité ou l'incapacité de Snapseed (je n'ai rien contre Snapseed, c'est juste le plus connu dans notre cercle) à rendre réelles les photos en noir-et-blanc.
Just taking the color away from a photo does not make a nice black-and-white photo. Doubly so when you have applied post-processing to it. Too often, we see people posting pictures in forums where the edges are darker than the body. How do these two topics fit together, you may ask? The answer is Rawtherapee. When you have a photograph where the sun is somehow shining into your lens, be it behind a cloud or peeking over a rooftop, it is not always the easiest to recover. This can be compounded when you took the picture in jpeg-format. In this issue, we want to tackle a photograph like that. Just to go from bad to worse, I will be using a jpeg instead of a RAW image.
La suppresion des couleurs sur une photo ne suffit pas à en faire une jolie photo en noir-et-blanc. En plus quand vous avez appliqué des post-traitements dessus. Trop souvent, nous voyons sur des forums des gens poster des images où les bords sont plus sombres que le centre.
Comment ces deux sujets peuvent aller ensemble, vous denmandez-vous ? La réponse est dans Rawtherapee.
Quand vous avez un photographie dans laquelle le soleil miroite dans vos lentilles, qu'il soit derrière un nuage ou pointant au bord du haut d'un toit, ce n'est pas toujours face à récupérer. Ceci peut être encore compliqué si la photo a été prise en format jpeg. Dasn ce numéro, nous voulons aborder une telle photographie. Pour aller juste de mal en pis, j'utiliserai une image jpeg plutôt qu'une en RAW.
This (bottom left) is what we will be working with. As you can see, the sun decided to peek out from behind the cloud as I tried to take a picture of the corpuscular rays. Since there is nothing of interest in the photograph, I would usually just send it straight to the bin. Let’s assume there was something in the image that I wanted. If we look at our histogram, you will see that black is actually squashed up to the edge as well as white. If I turn on clipping, you can see the problem immediately. Hectic loss of detail. (See the right-hand side and the bottom of the photograph.)
Turning this image into black-and-white should lessen the loss of detail. Alt+C, or clicking the third icon, will bring up the color menu. Find black-and-white, the fourth sub-menu and turn it on. This does not remove the loss of detail we can see with the clipping filters on, but it puts it into the realm of absolutes of light and shadow. Now we have a black-and-white picture that is still boring, but the loss of detail had become deep shadows. The next tool we are going to use is “local contrast”. This falls under detail, so Alt+D or click the second icon. A word of warning though, improper use of the local contrast can make your black-and-white photograph look extremely “shopped”.
The key here is the first two sliders, radius and amount. The larger the radius, the more feathering you will get from the edges. However, radius alone does nothing. This is where the amount slider comes in. If you are in the artistic mood, slide both the radius and amount to maximum. This will bring some drama to the photo, unless you have uniform dark areas that are not black. If you have those, it will look like a kid took a marker to the edges of the picture, before coloring it in with a lighter color. I actually encourage you to do this, then play with lightness level and darkness level to acquire the desired effect. Just keep an eye on your histogram, as we already have clipping that we are trying to hide. You do not want to compound your problems.
Drama!! But let’s assume you want clarity, rather than drama? We need to increase our zoom to 100%. Tip: don’t fret over details in the photo that are going to be cut in the end. By this I mean, if you are planning to crop your picture and you were going to cut off the left hand side, don’t worry about how your edit affects the object on the left. It is going to end up on the cutting room floor, so to speak. At 100%, I can zoom into the roof at the bottom and show you the difference between a radius of 20 (minimum) and a radius of 80. This is what you have to look out for when you use local contrast on a picture. Compare these two images (below)
Pay attention to the amount of visible tiles on the roof, from the edge. When using this effect on color photos, you may see a light discoloration on the side of the light, and dark discoloration on the side where it is dark. This is one very quick way to tell if a photo has been put through a filter. This is also the difference between editing by hand and using an application like Snapseed. Once your eye is trained to this, it is very hard to “unsee”. You will see this in some so-called “professional” photographs on the web, or even magazines. A good rule of thumb is that, when you see the dark edges start to appear, you can either decrease the radius and/or decrease the lightness, to “smooth things out”. I urge you to take a few photos and play with only this effect. It does not have to be black-and-white. That part was just to show you that you can save boring photographs or even a clipped one, by making it black-and-white, where that clipping does not matter as much any more.
Tip: Turn the effect on and off while being zoomed in, as well as being zoomed out. Local contrast is for sharpening; you do not want to add rifts or halos to your image. Once you are done, crop your image with the “C” key and you are good to go. I hope you had fun if you followed along and I hope you learned something. Disclaimer: In no way am I an expert in photo manipulation, I just know a guy who had a dog that gave me some fleas. I thought I may help you scratch an itch also. As always, if you have any questions or comments, send them to: misc@fullcirclemagazine.org