Wednesday, March 28, 2012

These are our tulips today

These Are Our Tulips Today
This is what they were doing three years ago today, during a more typical Wisconsin spring.

Magnolias another sign of early spring at the Arboretum

Magnolias in Bloom
I took these photos over the weekend at Longenecker Horticultural Gardens, UW-Madison Arboretum.
With more than 2,000 plants on display, this 50-acre area north of the Visitor Center is the premier collection of trees, shrubs and vines in Wisconsin. Recognized internationally, plantings were begun when the Arboretum was founded in 1934. Today, the Gardens hold major displays of lilacs (one of the nations largest), flowering crabapples (one of the most up-to-date in the country), viburnums, conifers (including a very large collection of arborvitae cultivars), and dozens of other plant groups.
Magnolia Emerging It's a spectacular place this time of year, especially with our unbelievably warm early spring -- one for the record books -- when everything seems to be blooming at least a month ahead of its normal schedule. No matter what the weather, it's worth a trip. If it's raining, take an umbrella -- there's a magical meditative stillness to the place in a light spring rain. And on a pleasant, sunny day, everything is erupting into one wild celebration of spring. And when Some of the lilacs have already bloomed, and the entire lilac collection is about to burst into full bloom. The magnolias also reflect this year's accelerated clock. The white ones are mostly beyond their prime already, with each tree shadowed by a ring of white blossoms on the ground below. The darker shades were just starting to bloom over the weekend.

Tuesday, March 27, 2012

Mirror slapping the moon around until it disappears altogether

Mirror Slapping the Moon Around Until It Disappears

Usually when I take a photograph of the moon, it's a sudden impulse shot with what I have at hand. Often I do everything wrong, shooting telephoto handheld at a slow shutter speed at an insanely high ISO. Sometimes it sort of works, in a blurry, expressive sort of way.

Last night, the moon and Venus (cropped out here) were close together, and the shadowed part of the moon was illuminated beautifully by earthglow. I thought I'd do it up right this time -- but everything went wrong.

I set the D90 up on a tripod with an 80-200 zoom. I turned the ISO way, way down. I turned off image stabilization, the way you're supposed to on a tripod. Turned on Long Exposure Noise Reduction, because I was tired of noisy night skies. I wanted a rich, deep black. Well, I got the black background. That's about it.

The multiple ghost moons are the result of "DSLR mirror slap." That's when the mirror in a DSLR swings out of the way of the film or sensor at the moment of exposure. It comes to rest against the pentaprism housing with a loud slapping sound. The resulting vibration during a time exposure -- especially with a bright subject against a dark background -- creates ghost images like this. Or in softer lighting, just a general softness. That's why most serious SLRs used to have a way to lock up the mirror after you composed your picture. Now many DSLRs don't, including my D90. So I experimented with different shutter speeds to no avail.

Then I remembered that the D90 has a workaround, buried deep in the display menu -- Exposure Delay Mode. When the shutter is pressed, this holds the mirror up for a couple seconds, letting the vibrations settle down, before taking the picture. I tried it. It works. But I noticed the moon still looked pretty soft, and Venus looked more like a micro star trail than a point of light. I was using such a long exposure -- 20 sec., don't ask why -- that the moon and Venus were visibly moving across the frame, visibly streaking and blurring.

Finally figured that out. I reset ISO, shutter speed, and aperture. I was set to take a technically flawless tripod shot of the moon and Venus. Looked up to frame the shot, but there was no moon. Clouds had moved in for the night.