Category Archives: Photography technique
Sometimes mistakes in photography can be the coolest thing.
I didn’t have the neutral density filter I needed to get a picture of the annular eclipse on Sunday, 2012.05.20, but, I was determined to get a picture of some type that would show the stellar event. To get a reasonably exposed picture of a person with the crescent sun behind him, I tried variations such as using the flash on full power in high speed synch mode, 1/8000 second, f/22, 100mm lens, focused a couple of feet behind a person who is at close distance… the flash just wasn’t powerful enough to do it that way (and, it is a powerful flash unit).
I was a little bit frustrated, but, being the addict to photography that I am, I started trying stupid things, like, putting everything on auto mode. I knew the sun would be way out of focus, but, I was hoping there might be a crescent shape in the big blotch of light where the sun is. I didn’t get that. What I did get, though, was a reflection within the lens that put a small, perfectly exposed, reasonably sharp crescent on the guys forehead! Very cool! Understand, I am using one of the best lenses available (Canon 100mm f/2.8 IS L macro), but, no lens will make pictures without artifacts when shooting directly into the sun.
I certainly couldn’t see the artifact when I shot the picture. The image in the viewfinder was way too bright for me do any more composing than squint, point the camera toward the person, let the auto-focus do its thing, and take the picture… no more than 1 second. Having the lens focus an image of the sun (that’s basically what you were doing when you used to roast ants with a magnifying glass) on the shutter curtain can damage the curtain, so, I knew I had to work fast.
The picture as it came out of the camera was pretty good, but, in Photoshop, I did make adjustments to Fill Light, Blacks, and Brightness, to give it a little more drama.
Here is an example of what happens when you photograph a painting with an on-camera flash. The light reflects straight back at the camera, making the painting seem “washed out,” especially toward the middle. Using a light on each side of the painting creates shadows on each side, but, the contrast and evenness of the lighting make it much more flattering. Having lights to the side also help show the texture and brushstrokes better… this picture is too small to see that though.
You could, of course, shoot the picture with the on-camera flash, as long as you shoot it from an angle. The painting would be skewed a little bit though, and, the lighting wouldn’t be nearly as even.
I read a pair of articles recently (here and here) about how to get a good image capture of a slide or negative without a dedicated film scanner. I have a dedicated 35mm film scanner (Nikon 5000 ed), but, I have a bunch of medium format film, which is about 5 times the size of 35mm film, that I haven’t been able to scan.
In short, you need a camera with a very good sensor (resolution and dynamic range), a lens that can resolve great detail and focus very close (macro), a diffused and even light source, a way to keep the film completely flat, and a way to very precisely keep the image sensor and film very close to parallel.
To keep the film flat, I cut holes that are about the same size as the image on the film (6x7cm) in a pair of pieces of cardboard, and sandwiched the film between the cardboard. With the lens I used (Canon 100mm macro), and the distance I needed to shoot from, I knew that there could only be about 2mm variance in the distance from the film to the sensor. It took about 20 minutes and quite a bit of experimenting with clamps and “braces” to get the film acceptably flat.
Today was very overcast, which made a bright and evenly diffused light source… Such clouds only come five times a year in the Phoenix area. I put the camera on a tripod, aimed at the featureless and evenly lit sky, removed as much dust from the negative as possible with a camel hair brush, and put the negative very precisely and evenly aligned on a tripod in front of the camera.
I set the camera to the lowest ISO to capture the most dynamic range and detail possible, and set the aperture to f/14 to get the most depth of field possible without having issues with diffraction. I had no idea how to expose, so I let the camera pick the shutter speed… 1/30 second, which worked out just fine.
I opened the RAW file in Adobe Camera Raw (ACR), but had no idea where to set the color balance, or any other settings, so I left the settings at default, and had ACR open the image as a 16-bit file in Photoshop. Negatives are a “compressed” format, and since I knew that I would be making huge color adjustments in Photoshop, an 8-bit file wouldn’t have had enough information to make smooth color transitions. .JPG files are 8-bits, and compressed on top of that, so I wouldn’t have been able to get anywhere near the number of colors needed if I had shot a .JPG. The top image shows what the capture of the negative looks like. You can see why I had no idea what color corrections to make in ACR.
I inverted the image, which means that colors are switched to their opposite color. For example, white becomes black, black becomes white, cyan becomes red, red becomes Cyan, magenta becomes green (and vice/versa), and yellow becomes blue (and vice/versa).
The inverted image was very flat, as to be expected. I could have adjusted the red, green, and blue manually, but, since this was my first try, I used some tools in Photoshop to help me get quickly to something close to correct. With the White Point tool, I clicked on an item that should be pure white… I chose a white spot on the cabinet that was in the sun. With the Black Point tool, I clicked something that I knew should be completely black, which was the shadow area of one of the bicycle tires. I made a manual adjustment to add brightness in the mid-tones. It’s still a little dark and blue-ish, so, if this was an important image, I would add some red and green to the highlights to brighten the image.
With my 21 megapixel Canon 5D mark II and ultra-sharp lens, the film grain is visible, and the details are sharp.
Basically, I have made a DIY slide duplicator. I’m very pleased that I have found a way to capture medium format film. I believe I could get excellent results if I took more than a few minutes adjusting colors, and use software to clean up the film grain (or, leave the film grain, for effect). I think I’ll get an old medium format enlarger film holder, and stick a diffuser on it.
This river radio was shot at the Salt River. These tubers do it in style!
Here are some pictures I shot of the dancers at Graham Central Station on Saturday: http://www.flickr.com/photos/davidduane/sets/72157626746109334/show/
I knew the lighting at Graham Central Station would be a challenge. There is some very harsh lighting, which makes for dramatic photos, but, it is not really bright enough for a lot of cameras to stop the action.
Taking action photos: This is one area where having a really good camera and lens makes a difference. For example, my camera (Canon 5D mark ii) shoots pretty well at ISO 3,200, and I use a fast lens that is reasonably sharp wide open… f/2.8. Even using this combination of body/lens, I had to increase the exposures as much as two stops in post, which means there is a huge amount of noise in most of the images. Cameras designed for sports photographers cost more, but they can shoot decently at ISO 12,800.
I put my camera in Program mode, and Auto ISO. That’s not being lazy… it just works extremely well. Program mode makes the shutter speeds progressively slower at the same time it makes the apertures progressively larger. Auto ISO raises the ISO when the shutter speed and aperture get too close to unusable for “standard” conditions. Better cameras than mine can be programed to more accurately control the relationships between shutter speed, aperture, and ISO, but, the settings on my camera work perfectly for what I use it for.
I knew that the tungsten lighting they use at Graham’s is 2,800 degrees, so I could have set the color temperature to tungsten and shot .jpgs, but I shoot in RAW mode so I can make extreme brightness changes in post.
Here is a full size picture to show how noisy it gets: http://www.flickr.com/photos/davidduane/5732218262/sizes/o/in/photostream/.
See how much nicer it looks when it is small:
This image was pushed 2.35 stops in post. The camera had set the exposure at 1/60 second. Since the dancers were moving toward the camera, the amount of blur is completely acceptable, and the image stabilizer worked magnificently.
Normally, I would have used my 50mm f1.4 lens because it only needs about ¼ the light as the 100mm f2.8 lens, but I wanted to see if I could get usable pictures with the long lens. The image stabilizer works extremely well on the 100mm lens, and the 50mm lens doesn’t have an image stabilizer, so that was another reason to use the 100mm lens.
I usually shoot bursts of 6 or so frames when the subject looks like it might be interesting. I shot around 400 pictures in 15 minutes to get that set of 32 usable dance pictures.