Tag Archives: aperture

World Pinhole Photography Day

Did you know that a pinhole can focus and project light? A pinhole in an opaque material is the world’s simplest camera! Yesterday was World Pinhole Photography Day.

History

The discovery of pinhole optics massively predates photography (the act of chemically recording a projected image). During the Renaissance, painters traced scenes projected onto a canvas by a pinhole on the opposite wall. The use of a pinhole to project images goes back to 5th century BC China.

A camera obscura uses a pinhole to project an image. Renaissance painters could then trace these images. (image source: Wikipedia)

Why Pinholes?

In an age of digital cameras and high-end optics, the pinhole endures, charming and simple.  In honor of World Pinhole Photography Day, I went on a pinhole outing.

You might ask, what is the point of pinhole photography in this day and age? There are aesthetic and practical reasons. I like knowing exactly how my lens works, for once. Even a prime lens can have upwards of a dozen pieces of glass in it. I have a good science background, and I can’t even touch that level of optics. A hole in black plastic. I get that. Pinholes have interesting properties. True, they don’t focus nearly as sharply as lenses. But because pinholes have such small apertures, they have nearly infinite focal depth.

Brief photography lesson: larger openings (apertures) allow more light and create shallow ranges of focus. This can be desirable in a portrait. Small openings permit less light and increase range of focus. This might be preferable for a landscape. Sufficiently small openings cause softening due to diffraction (physics of light stuff). If you shoot on an SLR, you may have noticed diffraction-caused softening on shots at f/22. The pinhole I use is f/177. This diffraction is what gives pinhole photos their texture.

The upshot: pinhole photos flatten a scene. Something a yard away will look similar to something 100 yards away. This allows a photographer to create interactions between different depths that wouldn’t be possible with a conventional lens. And finally, pinholes can create a really fun old-timey effect.

My setup

My setup is a bit like sticking a horse-drawn carriage on a rocket ship. I use a Lensbaby composer with the pinhole optics kit. My camera is a Sony Alpha 7s. Pinhole photography, due to the tiny amount of light transmitted, has slow exposure time. Exposures are often measured in multiple seconds. The Sony Alpha 7s is one of the fastest consumer cameras in the industry, with a maximum ISO of 409600. Thus, I was able to take decent handheld pinhole images even in low light by using high ISO.

Lenbaby pinhole on Sony Alpha 7s.

Lensbaby pinhole on Sony Alpha 7s.

The Images!

ISO 409,600, 1/6 second exposure. No tripod. Indoor shot on a rainy day.

ISO 409,600, 1/6 second exposure. No tripod. Indoor shot on a rainy day.

ISO 20,000; 1/60 sec.

ISO 20,000; 1/60 sec.

ISO 80,000; 1/60 sec.

ISO 80,000; 1/60 sec.

ISO 12,800; 1/60 sec.

ISO 12,800; 1/60 sec.

ISO 16,000, 1/60 second exposure.

ISO 16,000, 1/60 second exposure.

ISO 160,000, 1/10 second exposure. Indoor shot on a rainy day.

ISO 160,000, 1/10 second exposure. Indoor shot on a rainy day. I love how it looks like a 40s cheesecake shot.

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Macro photography methods: early spring blooms

Here in Virginia, spring is just beginning, and most of the signs of it are small and close to the ground. This spring, I decided to zoom in on that small world. Macro photography can be expensive, but it doesn’t have to be. For my photos, I used a 100 mm macro lens, some extension tubes to cut the minimum focal distance, and a kick light for illumination. If you don’t have a macro lens, you can also get great macro images using any lens with reverse lens macro. I used reverse lens macro to capture the image below.

Resistors with reverse macro

While I waited for a warm day, I practiced indoors. Below is an image of a civil war token lit with a kick light. Kick lights are great– they are small and bright, and you can couple them to your smart phone to control the color of the light. I chose blue here, thinking it might complement the copper tones of the coin.

Token the size of a penny. Lit using a kick light set to blue light.

Token the size of a penny. Lit using a kick light set to blue light.

In another exercise, I went to the kitchen and took pictures next to the window. This way I could think about natural light without dealing with the more trying aspects of nature like wind and the lack of convenient countertops.

A bottle cap in macro.

A bottle cap in macro.

Finally I got a nice day. My first subject was a lenten rose. Viewed from above, these early bloomers look more like shrubs than flowers. Only from below do you see what pretty flowers they are. Which means getting underneath a shrub-height flower.

I used a kick light to pull up the deep shadows in the middle of the flower. A gorilla pod (a simple $10 mini-tripod/flexible grip sort of thing) let me get the kick light where I needed it. After some trial and error (and some laying in the dirt and cursing the glare on my view screen while simultaneously really appreciating the view screen since my older camera doesn’t have one), I got this image below. With the aperture set to f11, the depth of field is good. A few of the stamen are out of focus, and I wonder if another stop or two would have captured them. I didn’t notice them while I was taking the image. Still, pretty pleased with this image.

A lenten rose in macro, lit from beneath with a kick light.

A lenten rose in macro, lit from beneath with a kick light.

Next I found some scilla. These flowers are electrically blue, but they are dinky. Each flower below is about the size of a penny. They were growing in deep shadow, so again I used the kick light, this time more to achieve the contrast and the white balance I wanted.

Scilla flowers in macro.

Scilla flowers in macro.

Later, I found some moss growing on a brick. For this image, I used my extension tubes. They cut the light, but they allow great and affordable zoom. This was in full sun, so I didn’t need the kick light. I find this image slightly creepy, like those tendrils are going to grow into the pine cone and consume it. Here the aperture is f4– this was for effect rather than for exposure.

Moss and pine cone on a brick in macro.

Moss and pine cone on a brick in macro.

And finally, my favorite image of the day, a lovely purple crocus. This shot was just a matter of playing with angles and trying to stay in focus. Happy spring, everyone!

Crocus in macro.

Crocus in macro.

Books and pictures and programs

These last few weeks have been a whirlwind, so in departure from something more organized, I think I’ll just list off a few of my projects. Hopefully some of them will inspire you to something; at the very least, I know I can come back here when my own motivation wanes (it always does, it always will, we just have to learn to re-energize it).

  • In the last few months, I’ve assembled a science fiction and fantasy anthology for my writing group. I did all the formatting and editing and layout. Last night we had a binding party in which we put together several handmade copies. Soon it will be available for the kindle (after a little more work), but here are pictures of the first bound copy of Bizarre Tales from the Three Notch’d RoadSONY DSC SONY DSC
  • I’m taking a watercolor painting class through a local art community. Everything I know now I taught myself, and I’m sure there are new things I ought to learn. The next Zish and Argo will be even more beautiful.
  • I’m taking the plunge and going pro with my photography. Check out my new website karenblahaphotography.com.
  • I’m learning database design, something I knew zero about before June. You can just pick up a new skill, if you give it time and realize that it will be a slog at times. I’m using this book by Michael Blaha, which as the name suggests, my dad wrote. Nearly 30 years of osmosis didn’t teach me anything, but two months with this book has been inspiringly instructive.
  • I’ve been learning the Adobe creative suite, using videos from Lynda.com. I learned InDesign for the anthology pictured above. I learned a ton about Illustrator after being unable to make even the simplest graphics in it. Although I’ve been using Photoshop for years, I’ve learned more about it in the last month than I have in the last ten years. Immensely eye-opening.
  • I made the switch from Aperture (the mac photo-managing software) to LightRoom (the Adobe photo-managing software). LightRoom ties into creative suite better, and Mac is not supporting Aperture sufficiently anymore. And I’m using Lynda.com videos to speed my adaptation to LightRoom too.
  • I discovered a wikipedia for classical music whose copyright has lapsed. Imslp.org has sheet music for hundreds of composers for dozens of instruments. It even has some free recordings. I am working on learning Gilbert and Sullivan’s H.M.S. Pinafore for piano, Grieg’s  Peer Gynt for piano, and Saint Saen’s Swan for viola. The only trouble is knowing which music you want!
  • I continue to work on short stories for my Clarion Write-a-thon goal. I’m on the second one, and I need to pick up the pace. Check out my profile page here.
  • And finally, I continue to work on my 100 scenes of Vironevaehn life. I’m up to 42 color illustrations.SONY DSC

Whew, that was a lot, and time to get back to it!

Sports photography

When I go to sporting events, I like to take pictures. Sports photography is really challenging, especially if you operate on a limited equipment budget and don’t get any kind of special access. I’ll list a few challenges I’ve encountered, and how I solved them. I shoot with a Sony α-850, but learned on a Sony α-100, so my experiences should translate to any basic SLR camera.

Challenge 1: The lighting isn’t strong enough

Whether you are indoors or the light of day is fading, this immensely effects the kind of photos you can take. My camera is susceptible to graininess at higher ISO numbers, which I hate. I set the ISO to the highest number I can stand, then I shoot in aperture priority mode in the smallest f-number (largest aperture) possible at the zoom required. I like to turn down the exposure by a couple of stops; it is easier to add brightness to an image than to remove blur. You may also need to add some saturation if you under-expose.

I used this procedure to take the picture of Michael Phelps swimming, below. Incidentally, this is the picture for breast stroke and swimming on wikipedia, and for swimming on Facebook. If you aren’t trying to make money off your photos, you can have some great fun seeing how they spread if you add them to the creative commons. (support the creative commons!)

 

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Challenge 2: The lighting is not white light

This can happen both outdoors with twilight or cloudy conditions, or indoors with certain types of lighting. The indoors case is a lot harder to deal with because it is harsher and more unnatural. There are a couple of different strategies– you can be proactive and take a reference picture of a white object during your shoot. You can change your white balance to match this reference during then shoot, or later in the post processing (I post process in Aperture), you can set the temperature/tint for all the photos to the combination that makes the reference shot a neutral color. If you change angle, the color of the light may change, so if you shoot from many angles this gets hard no matter your strategy. I always do my color changes in post-production. If you wish to, it’s important to shoot in raw (rather than jpg), otherwise you can degrade the image.

The pair of images below show a picture with and without temperature/tint correction. (I have also increased the brightness and saturation, but little else.) Note that the skin tone is more ashen in the first picture. I used the bonnet and the goal posts to hone in on a good neutral.

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Challenge 3: The focal plane changes rapidly and fast movement

When shooting sports, I always want to shoot with the largest aperture. This way, I can shoot at a lower ISO (i.e., less noise) and still have fast photos. Additionally, uninteresting stuff in the background gets blurred out by the focal depth. However, this shallow focal range ruins the picture if the objects of interest aren’t in that range. For some events, getting the objects in the focal plane is harder than capturing without motion blur, so I increase my aperture to the f5-f8 area.

Below is a picture I took at a horse race. Horse races are the best example of what I described above– the horses thunder towards you so quickly that in the time it takes for a cheaper SLR to focus, the distance of the horse has changed a lot. If the focal depth is shallow, the horse is likely not in it. But there is plenty of natural light, so I can increase the f-number without getting too slow.SONY DSC

Happy photoing! There are myriad other sports photo problems to solve, but I think I’ve been long-winded enough for today.