Wednesday, May 30, 2018

Jewels Underfoot XI: Marina del Rey black sand

One day I was walking along the beach, just being there. I ended up going south of the Venice Pier, all the way to the Marina del Rey entrance channel. Can't go farther south from here without a boat.

I noticed a patch of darker sand up at the high tide cusp.Taking a closer look I saw that it was black, unlike anything I've seen here. My first thought was that it was polluted sand dredged from the channel, which idea a lifeguard corroborated. As I thought about it, though, this didn't make much sense. I picked up a handful and washed it in the ocean. Nothing happened. It didn't feel oily, it didn't float, it didn't dissolve. I found a cup and took some home for a closer look.

Later on I went back for more. About halfway back home from that trip I began to feel the weight. This stuff is more dense than the common sand. I did some research.

Magnetite forms in swamps. Ballona Creek used to be a swamp. How this small patch of magnetite ended up here I don't know.

When I took some macro photos I got a surprise. Most of it is black and fine, but there are other characteristic grains mixed in, such as garnet. What a fascinating sculpture could be made with this sand.

This sequence of photos zooms in step by step. The first one is the full frame scaled to the blog dimensions. These first three were shot as an experiment on a cloudy day using manual white balance from a grey card.. 
Click on any image to see it full size.

The image below has been cropped to about half the original frame, then scaled to the blog to get in closer.

This image is at maximum size, cropped to actual pixels. The area is about 15mm wide.

This maximum magnification image was shot earlier under sunlight with a diffuser.

Not being all that happy with the photos taken under cloudy light, I took some more today. The day was clear, just a high white haze, so I used a diffuser to cut down the specular highlights. The original is 6720 pixels wide; I cropped that to 3360 and then scaled to 1536 and used unsharp mask.

Friday, May 18, 2018

Jewels Underfoot X: Dunhuang, China

A co-worker went to tour parts of China, and took a camel ride near Dunhuang on the Silk Road. He brought back a sample of sand for me.

It's beautiful sand, and tricky to get the color balance. The new GIMP 2.10 makes some of this easier, so I made a new edit on one of the photos. These were photos I took before I had better control of the photography itself.

The Unsharp Mask took in GIMP 2.10 is also better. Easier to use, I can see the effect, and does a better job os sharpening with fewer artifacts. This image is the best I know how to do... right now. Click on it to get a bigger version.

I wasn't all that happy with the color balance in the Dunhuang sand. It's very sensitive to variations in light and nothing looked right. So, I did a manual white balance from a grey card and got color I liked better.

Then Blogger threw a wrench into the works. With the camera pointed straight down, it doesn't really know which way is up so it makes a guess. Some images are properly horizontal, others are rotated 90 degrees, and some are rotated 270. GIMP asks me what I want, and brings the image in horizontally. I do the edits. Upload to Blogger and it goes by the original EXIF data, which makes the lighting strange to my eye.

I tried various ways to get the image horizontal. The only one that worked was to open the image with Digital Photo Pro, rotate, export as TIFF, edit that in the GIMP to do color balance. Yes, it comes out horizontal as I want, but yeow. What a hassle. There must be a better way.

The image below is of the manual white balance one, but it's a quick edit to see if the concept works. I  overdid the contrast adjustment. I also notice a color shift between the thumbnail below and the enlarged view; the latter goes pretty strongly green-blue. Sigh. This works better in Second Life slide shows, where what I import is what I see on the display.

Thursday, May 3, 2018

Jewels Underfoot IX: Hawai'i Mauna Kea Beach

This sand is from Mauna Kea Beach on the big island.

Jewels Underfoot VIII: Hawai'i Hapuna Beach

Here's another new look at Hawai'i sand. This is from Hapuna Beach, at Kohala on the northwest coast of the big island.

Photographs taken with a 100mm macro lens on a full-frame digital SLR camera at closest focusing distance. Sand is on a white porcelain platter under a diffuser, with the camera looking straight down.

Sand from Hawai'i Hapuna Beach. Click to enlarge.

Sand form Hapuna Beach. Click to enlarge. For some reason, Blogger wants to show this vertically. It should be horizontal, upper end to the right.

Sand from Hapuna Beach, Hawai'i. Maximum magnification, 1:1 pixel view. Should be horizontal with upper end to the right.

Jewels Underfoot VII: Hawai'i Punalu'u Beach

I recently gained access to three more samples of sand from Hawai'i (the big island). This sample is black sand from Punalu'u Beach, on the southeast coast. It's fascinatingly different from the black sand I've seen elsewhere.

I'm guessing this sand is older, due to the polish and the lack of olivine. In direct sunlight it sparkles brightly. All images here were taken using a diffuser to cut back on specular highlights. 100MM macro lens on full frame digital SLR, mirror lock-up, self-timer. The sand is on a white porcelain platter.

Punalu'u Beach sand. Click to enlarge.

Punalu'u Beach sand, closer view. Click to enlarge.

Punalu'u Beach sand, maximum magnification, actual pixels. Click for full size.

Thursday, December 7, 2017

Jewels Underfoot VI: Hawai'i, Maui Wailea Beach

A co-worker must have brought this sample to me. I don't remember.

I now do the photography with a 100mm macro lens on a full-frame digital camera, with a diffuser to soften and spread the sunlight. The sand is on a white porcelain platter, placed close to the minimum focusing distance so the magnification is close to 1:1 on the sensor. In editing I adjust color balance and contrast moderately, so details show up better. I crop a roughly 4000-pixel-wide section from the original image, and scale that to 1584 X 1056 pixels for the blog. The final step is a modest unsharp mask.

Because I'm more interested in showing the beauty of the sand, the scale in these images varies a little, from about 3cm across to 3.5cm. I show multiple images of the sample because one isn't enough.

Hawai'i, Maui, Wailea Beach
Click on an image to see it full size.

Friday, December 1, 2017

17F-3 (December 1)

Dealing with Conditions

The free-piled sculpture of two days ago convinced me that any further sculpture done in this tide window needed to use a form and filter. I told Deb that, weather permitting, I'd be out on Friday. Thursday would have been good but I had to pick up my car after getting a replacement catalytic converter. They're easy to steal from 2008 Elements.
     Weather did permit. The morning came up calm and clear. I leaded the cart, ate lunch and headed out.
     The sand was as expected. I really should have motivated myself to finish the new screens, as I had to struggle with sand grains of the size that plugs up the Box Filter. Piling was slow. Sand has gotten heavier, I think, and water farther away.
     Four full loads will fill the form to the top, with a little left over. I picked up three full loads for this shorter day, and that was about right. By the time I was done... I was done in. It was a good pile.

Build number: 17F-3 (lifetime start #345); monolith on low sokkel
Title: "Lines"
Date: December 1
Location: Venice Breakwater, isthmus south side
Start: 11:00, construction time approx. 4.25 hours
Size: about 33 inches tall, 21 inches diameter
Technique: Latchform, Box Filter 2, three full loads intertidal sand
Digital Images: 48, EOS-5D Mk IV and 100mm F/2.8L, tripod and handheld
Special photography: macro photos of sunlit sand in finished sculpture
New Tools: none
New Equipment: none

I hadn't given much thought to what to carve. Between struggling to care at all, and balancing my new Second Life responsibilities, scheduling a sculpture is hard enough. Planning it is even harder. Load the cart and go. So, now I have this pile and not much of an idea what to do with it.

Well, it is pretty on its own. Finally I get a vague idea for a big opening on the sunlit side that will come out the top. I carve a curving surface for the hole, and then change direction. The space goes to the bottom instead, with a broad curving piece over the top of a kind of Gothic arch. I can tunnel upward and come out the top.
    So, I start shaping the top. There's really no hurry, so I shave off thin layers, then remove the sand with a hand. The curve begins to look good, and suggests another idea. I continue shaving and shaping, and smoothing with a hand. The afternoon sun brings subtle shadow to the surface.
    I like that as it is. So, I'll put the opening somewhere else, like down below. Again, there's not need to be quick, so I carve slowly and leave enough sand for further shaping inside the space.
    The rest of the sculpture goes in like fashion. Time taken to consider and connect the various lines. A part on the north doesn't fit, so I cut it back and merge it with a space that connects to the center. I've done things like this before, but as Rich used to say, "If you can't make it new, make it better." I made it better this time, like it belongs.
    The whole sculpture shows a sense of balance that has been lacking in recent pieces. Nothing looks awkward, and there's no ugly side/pretty side conflict. It's massive, although short, with strong presence, yet has a kind of springy look from certain angles.
    It's certainly popular with passersby. One of them, Rita, a sculptor from Italy, takes the time to take many pictures. While I'm talking with her, Deb arrives.
    "Nice to see you, Deb!"
    "I'm glad i made it in time."
    "I didn't expect you to be here, after you mentioned needing to wait for the gas company."
    "That all went well."
    She wanders off to look around the beach, which is really lovely in the evening light. As the sun nears the horizon, the light softens and caresses sandy curves. Other people pause to look at the sculpture.
    I'm having trouble thinking. I hope some of the photos come out. My mind keeps skipping things, and the low-angle light makes it hard to see in the viewfinder. Exposure is mostly a guess.
    Two men from England stop and chat for a bit. I try to talk them into coming back and helping for the next sculpture, but they'll soon be returning.
    The sky glows, but the sun is gone from here. I gather enough wits to gather equipment and stow it in the cart. A last site check and walk around the sculpture, and then homeward bound in the falling light.
    I pass by a young couple who'd stopped to talk. Now they're taking a self-timer shot with an artwork on a board they'd bought on the Boardwalk. They invite me to join them for another photo. And then I make my way across the beach and north along the Boardwalk, avoiding the hills on the alley route... and the Friday traffic.
    A quick check of the images at home shows that ast least some of them are decent. Good. First time I've had a chance to photograph in sunset light with the new camera. Dinner, shower, bed. With a short pause to write a basic report.
Post-sculptural addendum:
Looking through the images in more detail, the mystery deepens. Exposures range from severely burned to nearly black, and many are also out of focus. Finding three images that will work for an image assembly is a problem... for one or another problem. Usually I don't have so much trouble.
    In the afternoon of the next day, when a more-or-less quorum of brain cells have struggled out of the post-sculptural fog to think about things, it becomes logical to see how the camera's metering is set. It has several modes. I find that I bumped the wrong button at tome point and sent it for a special metering mode that didn't work for my purposes. Learning curve. I knew something wasn't right on the beach but couldn't concentrate on figuring it out.
    I'm also changing the way I do things. Manual exposure can be consistent but wasn't for this sculpture, because of the mis-set meter mode. So, I switched to automatic exposure and used exposure bias to tune, which also didn't work, for the same reason.
    The focus issue... I don't know. I must have thought I was set for auto-focus. But that doesn't work well on the shaded part of the sculpture. What with sand on my glasses and sunlight in my face, I was having a hard time seeing anything at some angles.
    Best solution: Hire a photographer who can be a real photographer instead of an end-of-the-day sand sculptor. Second best: Set the camera to all automatic and shoot a round of contingency photos. I did that for the previous sculpture. In any case, remember to check the camera's settings before starting out, and after changing any settings.
    People adapt. Use a camera with a malfunctioning meter long enough and you'll get used to it, and make photos that are consistently well exposed. There will be a surprise when you pick up a new camera and, perhaps, try to figure out which one is "right." All meters are different. It has taken me some time to adapt to this one's interpretation of light and, just when I thought I understood how it worked, it changed. If I'd have been more alert at the time I'd have thought to check how it was set; given the overlap of controls it's easy to set one thing when intending to set something else.
    The final truth is that this sculpture didn't come out well, even in the better photos. This has happened before. Some sculptures translate to photographs better than others. They really want to be an object in space.
    My experiment of taking a macro photograph of sand in the sculpture didn't work out so well as I'd hoped. With the sun in my face, seeing the exposure meter was hard and I overexposed the images. The close working required having the camera's image plane parallel to the sculpture. My weary eyes caught some of this but not all. And then there's a more fundamental problem: like looking at a cloud as you approach it, the boundary becomes very fuzzy when close. Horizons that are obvious at normal distance become much harder to see up close. They can be seen, but they're not obvious. Even with the problems, though, the sand is pretty. Improved technique should help, too: self-timer and mirror lock-up to reduce camera shake that affects close shots.
Santa Monica
2017 December 1, 2

17F-3, "Lines"
Click on an image to enlarge

Here's a macro shot of the upper surface in the above photo, shot from about 7 inches away with the 100mm lens.


Nearly full moon, at perigee.