Archive for July, 2008

Tips for dealing with High ISO Noise in Capture NX

Monday, July 28th, 2008

IHateHamlet_08

When working in low light, shoot in RAW and err on the side of overexposure.

If you have to shoot using high ISOs, the best way to prevent noise from building up in the shadow areas of your image is to make sure not to underexpose. If you shoot in RAW, you will be able to recover mild blown highlights (but don’t go crazy — there are limits to what you can get back with RAW) quite cleanly, but if you try to recover detail from the shadow areas, noise will eat your lunch.

If you’re using Capure NX 2, the easiest way to recover the highlights is to use “highlight protection” in the quick fix menu. In NX 1.x, you can reduce the exposure compensation, then tweak the levels and curves to make sure you don’t bring down the midtones.

Turn off in-camera sharpening and noise reduction

In-camera sharpening is not very intelligent. Either turn it off in-camera, or else turn it off in Capture NX before you begin editing. In-camera noise reduction is both dumb and slow, so definitely turn that off in-camera.

Think locally, act locally,

Sharpening and noise reduction are not mutually exclusive, but they’re close. When you reduce noise, you reduce sharpness. When you sharpen an image, you sharpen the noise. You can ameliorate this somewhat by tweaking the settings — increasing the “sharpness” slider in noise reduction, and careful application of high pass sharpening (and avoiding unsharp mask if possible) will both make it easier for you to have both sharpness and noise reduction in the same area.

But it’s not likely that you need every inch of your image to be sharp, and it’s not likely that every inch of the image needs the same degree of noise reduction. So, apply both your sharpening and your noise reduction locally, where each is needed most. This is easier in Capture NX 2, because selection control points allow you to work quickly to isolate the areas you need to effect. Just drop selection points at full opacity in the areas you want sharp and partially or totally reduced points where the image is supposed to be soft. Similarly for noise reduction.

Of course, sometimes you’re going to have a lot of noise in areas you need sharp — it can’t always be avoided.

If you don’t have NX 2 yet, you can perform the same localization by masking the areas in question manually. This will be much, much, much easier if you have a Wacom tablet. It gets tedious very quickly is you use a mouse.

Intensify the highlights and shadows

If your image contains dark shadow area where detail is going to be lost anyway, or where the detail is really noisy, consider using control points or an LCH adjustment to shove those areas closer to pure black. Also brighten the lighter areas where noise should be at its minimum already.

Convert to black and white

Noise looks better in black and white. use the BW conversion menu, play with the filter settings, find what works best for your image.

Convert to black and white, even in color

Bear with me. Even if you’re going to want a color image as your finished output, you may want to make a trip to the BW conversion menu. Try converting to black and white and playing with the opacity settings. Often a conversion with partial screen or multiply opacity can help emphasize the areas of an image you want sharp, especially if you figure out what color filter setting to use.

Convert to black and white, again

I’ve found that in some situatuions, it’s helpful to do a blue-filtered BW conversion applied with partial screen opacity, followed by a second black and white conversion applied normally or as an overlay, with green filter setting. Sometimes this helps brighten and clarify an image without increasing noise.

Not sure exactly under what conditions this works best; I’m still experimenting.

Desturate the noise

Dishes @ ISO 1600

Here’s another area where Capture NX really shines. If you’re going to keep the image in color, one way to make noise more pleasing without actually having to reduce it is to drop a control point into some of the noisy areas, crank the saturation to 0, and then drop control points into areas that are relatively noise-free but otherwise similarly colored. The effect will be overall reduced saturation and a possible change in color balance, but if done correctly, it also renders the noise less noticeable and more like film grain.

Nick vs. Composition

Saturday, July 26th, 2008

Composition is something that I sometimes find quite difficult. When composing an image, there are two things that you need to (or at least ought to) achieve:

* Fill the frame with what is important. Exclude what is not.
* Find the framing which places the elements in the frame in the correct relationship to one another.

Everything about this process is subjective. How do we decide what is important? How do we decide how objects and shapes and colors are supposed to be related to one another? These are not things one can prescribe. But unless attention (whether this attention takes the form of conscious deliberation or something else) is paid to these issues, the resulting image is likely to be poorly composed. Which does not mean that it fails some test or will be butchered on critique forums; it means that the viewer will not be able to get past unhappy accidents of composition to whatever it is that the photographer was trying to share by means of the photograph.

My habitual approach to composition is to find something that seizes my attention and get close enough to it to fill the frame with it. With birds, this is usually straightforward. You find a bird, you get as close to it as you can by using the longest lens and by using your feet as much as you dare. And it’s not hard to use the same approach with macro photography or with non-macro close-up work. Heck, it even works for portraits, up to a point. No good for landscapes, but I find landscape photography to be utterly abominably boring, so that’s no big deal.

But you know where it doesn’t work? With my Olympus XA. The XA doesn’t have very good close focusing capabilities, and it’s semi-wide angle 35mm lens is not good for cherry-picking elements from a scene. And the images I’ve gotten from it so far have not proven amenable to deep cropping. This has forced me to start looking at a different scale than I usually look — forced me to take a slightly wider view, as it were. In particular, I find myself having to look for multiple medium-large objects covering an area of 10-20 feet and at least 5-10 feet away.

I find this to be surprisingly difficult. But after running quite a few rolls of film through the XA, I believe I’m starting to get somewhere with it.

Two Chair Backs

In this example, the element that caught my eye was the shadow of the two adjacent chair backs sitting at the bottom of the pool of light projected through the window of this restaurant. I couldn’t capture just that shape with the XA, and even if I could, there would be no real up-shot to getting closer. There was no deal to be had; just light and shadow, only the shape of it. So I worked to carefully include the mundane elements at the border. The legs of the chairs provided context, located the image. The additional illuminated areas pointed beyond the frame, implied repetition.

Portra 400-001-27

Here, it was just a sort of race to contain all the repeating shapes — lines, intersections, angles, squiggles. This is from a construction project near work that I’ve been trying to make good images of for a while and mostly failing — it’s almost done now, so I’m not going to get anything more out of it. It’s tricky, because the immediate vicinity is filled with very boring architecture, boring lawn, etc. (And not even boring in an interesting way.) This was the vantage that allowed me to include as much of these proliferating shapes as possible with as little of the devstatingly uninteresting context as possible.

I’ve also started trying to import some of this awareness back into my SLR shooting, so that just because I can discard the majority of a scene in favor of one compelling element, I don’t automatically do so.

The Point Stays Free

I shot this with my D40 from many, many different angles, each of which proved totally unsatisfactory. I had just about given up, and was actually in the process of moving out of the way to let a driver pass, when stumbled into this angle — one which contained the lines in the concrete, the curving cracks, and the fixture in the lower left — and which contained them in a configuration and proportion which retained something dynamic about it.

Pepper and Salt (Portra 800:004:28)

This is an example from my Nikkormat. I had my 55mm f/3.5 Micro, and I actually succumbed just moments after this to the impulse to use it to get a full-on (and fully tedious) close-up of the pepper shaker’s top. But before I did, I paused to get this shot, with the 35mm f/2 O, which includes the salt shaker companion in the background and the lovely, blank green expanse of the table.

Electric Slide, Part II

Friday, July 11th, 2008

Astia-002-29

As discussed in a previous post, I recently shot my first roll of slide film. Well, now I’ve shot a second, applying the knowledge I gained from the first roll (to wit, Astia is best shot more or less as metered). I’m still struggling with difficulties in the scanning process; to the eye, many if not most of the slides are beautiful and sharp, with just the right degree of saturation and contrast. My scanner chews them up and spits out muddy scans with weird color casts.

Astia-002-21

After the last roll, I more or less convinced myself that the thing to do was to bypass Silverfast’s settings, take a totally flat file into Capture NX (my editor of choice, even though it’s more geared toward digital capture than scans) and go from there. I tried that this time, and in some cases, it worked great, but in many — especially where the scene was particularly contrasty — I wasn’t able to do anything useful with the resulting files. I had to go back and re-scan, doing my best with the contrast and, in particular, with the color cast. I’m getting better at this, but it’ll be a while before I can churn out consistent scans that really look the way I want the to — if indeed that’s actually possible with my scanner.

Astia-002-10

Meanwhile, I’ve gotten my hands on a couple rolls of Ektachrome E100G. In the world of negative film, I’ve always preferred Kodak to Fuji, mainly for reasons of color palette. I’ve also always found Kodak film much easier to scan. Notwithstanding, I really do love the look of Astia, but I hold out hope that Ektachrome will prove easier to digitize. This is important, because my life is substantially digital, and while I’m growing to really appreciate the possibilities of the film medium — and even to enjoy darkroom printing — I really don’t have much use for content that I can’t effectively import into my online world.

In the Kitchen

Sunday, July 6th, 2008

DSC_2097_20080705_1656

It’s easy to forget sometimes that you don’t have go very far to find strange and wonderful scenes for your camera. And it’s easy to become so accustomed to objects that you encounter regularly that you cease to really see them, until a maniacal sunbeam comes in from some obscure angle.

Soap Bottle

Translucent objects begin to glow; reflective objects project alien landscapes across familiar surfaces.

Tape Dispenser

Everything becomes a mystery, if not two or three…

The Point Stays Free

Thursday, July 3rd, 2008

The Point Stays Free

It isn’t easy for me to compose with the full frame. There are a lot of reasons for this. Some are basically ineluctable. My cameras don’t have 100% viewfinder coverage, and I wear glasses, meaning that it’s sometimes hard for me to see the entire viewfinder at once in the first place. I also shoot a lot of birds, and it’s very hard to fill a whole frame with a bird unless the bird is domesticated, taxidermied, or drugged. And when it comes to the black and white shooting I did for my class, I ran into trouble when I did fill the frame, because I was printing 35mm frames on 8×10 paper.

But some of my problems with full-frame composition have to do more with how I think and see than the physical and technological constraints placed on me by my body and my materials. I usually shoot handheld in a rapid-fire fashion, so that I can keep moving, avoid attracting attention from potential muggers, and maintain my flow-stateish condition of just seeing and shooting. Because of this, I’ve developed a habit of shooting to fill a comparatively small portion of the frame and then cropping rather severely in post-processing. There’s nothing inherently wrong with this — I’m not sympathetic to the anti-cropping purists — but it does create possible issues of resolution.

This image was a case in which I could tell immediately that it was important that I determine my composition ahead of time. There are many compositional elements, and the whole ensemble was required for the image to work. It was critical that I include everything in the frame, and because of the peculiar shape of the overall composition, and the physical dimensions involved, it was also critical that I make sure everything was already in its place at the moment of capture.

So, I took some extra time, even though it meant briefly obstructing this driveway. I’m glad I did, too, because the first several versions of this shot — taken from a whole different angle — were basically unusable. In fact, it was only after I lost my game of chicken with one of the cars trying to use the driveway that this angle occurred to me. : )