Looooong exposures are your friend

So I went to the quarry cave again, this time with nonspecific. I hooked up the remote switch and set the camera to the bulb setting, so I could hold the shutter open as long as I wanted. Then came the fun part… using my extra-bright flashlights to “paint” the cave with light, only lighting the areas I wanted. It was nearly dark by the time we left, and definitely dark by the time we made it back to the car. As nightfall approached, a heavy mist settled into the cave, making for a surreal experience. When the lights were off, it was pure black, and when on, it seemed pure white, and you could barely see any better. Also strange, was that just 10 or 15 feet apart, and I couldn’t understand Kara at all, due to all the echoes. In short, I had a blast. :)

Then suddenly, photos:

Near the entrance:

Exposure Time: 30.000 s
Aperture: f/5.0
ISO equiv: 400
Lighting: natural lighting from left, lesser so from right, fill-in by flashlight

Side chamber:

Exposure Time: 77.000 s
Aperture: f/7.1
ISO equiv: 800
Lighting: generous and erratic use of 2 high-power flashlights :)

Side chamber:

Exposure Time: 156.000 s
Aperture: f/7.1
ISO equiv: 800
Lighting: No flashlights close the camera or within line-of-site of the lens. Two flashlights were held fairly still for about 45 seconds, and then waved around for fill lighting for the remainder. This seemed to work well, and cut down on the mist haze, getting a crisp view of the far wall.

I also took more HRDI fodder, we’ll see how that goes.

High Dynamic Range Imagery

The batch from the tunnel didn’t work out due to a lack of bright data (I really did need the tripod after all) but I think I’ve got the hang of it now with properly exposed photos and the newer software. The photos show some differences due to variations in the settings… I’m still deciding what I want these things to look like.

HDRI = High Dynamic Range Imagery. Take multiple photos of a wide contrast scene, varying the exposure up and down to capture the full range of data available. Using special software, you combine the images, and use tone-mapping to convert the scene-wide contrast into “micro-contrast”. This compresses the tonal range a bit, and enables details that would have been lost to come through.

Here’s some images I made a couple years back to explain it…
http://www.vaughnsphotoart.com/miscimg/hdr1.jpg (3 exposures)
http://www.vaughnsphotoart.com/miscimg/hdr2.jpg (result)

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Abandoned Mine Tunnel

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I had hoped to have some high dynamic range images for you, but that hasn’t been going so well. For one thing, my tripod was in the car, which was with Melanie in Big Stone Gap. Beyond that though, I just having trouble getting the HDRI’s to come out. I’m not sure if it’s that the source images were too dark, or I just don’t have the knack of the settings. But I’m having trouble making anything that is an improvement over a regular image.

The rest of these images are the surrounding area.

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9. ezerick in the background… A rather large piece of concrete in the foreground

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Canon 5d Mark II infrared test

It seems the 5d Mark II is slightly less infrared sensitive than the Mark I, but with suitably long exposures I was still able to get some IR magic. Usually I convert IR to monochrome, but for some reason I was really digging on the hues the filter was producing, so I desaturated them a bit and went with it.

Results are below… note that these pics seem to have a hotspot near the center. I believe this was due to a smudge on the back of the lens. I didn’t notice the hotspot until I downloaded, and went searching for the cause. Nice greasy smudge, near dead center on the rear glass. Can anyone confirm this can cause a hotspot in long exposures?

No idea how I managed that one… I am so careful. Alas. Anyway, I’ll retest, sans-smudge, soon. The trees look excessively fuzzy because it was windy, and these were 6-15 second exposures.

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