Dandelion Problem

Just in case you think you've got a dandelion problem. This shows only about a quarter of the field, too.

I have to say, though, it's really quite pretty around the region while the dandelions are in bloom. You see patches of yellow like this all over the place. It doesn't last long of course, but that's the problem with flowers.

Speaking of pretty, look what else I found. I usually take a "test shot" of my shed with any new camera, and I was poking around in the image at high resolutions enjoying the details and the lens rendering. (Michael Reichmann coined a term for this that stuck: "pixel-peeping.") Here's the full image:

And look what I found:

This is about 200% after you click on it. Is that some funky-looking interference pattern, or what? Evidently aliens have made my shed into a hidden communications relay station or something. A lovely little accident.

I went out photographing in the wet this morning, so I have a bunch of new stuff to look at. Sony files seem to play very nicely with Photoshop and ACR.

Mike

Book of Interest this week:

How Photography Became Contemporary Art: Inside an Artistic Revolution from Pop to the Digital Age, by Andy Grundberg, Yale University Press, 296 pages. A longtime critic and observer attempts a synthesis. Good reading. Also available from The Book Depository with free shipping worldwide.

Original contents copyright 2021 by Michael C. Johnston and/or the bylined author. All Rights Reserved. Links in this post may be to our affiliates; sales through affiliate links may benefit this site.

(To see all the comments, click on the "Comments" link below.)
Featured Comments from:

Romano Gianetti: "Welcome to the fashion of removing antialiasing filters on our cameras. As an electronic engineer, I fight with it every day...and I am appalled at the idea that people prefer apparent sharpness to a more correct sampling of the real, analog world. This is a clear example of aliasing: impossible to remove after the fact...and unfortunately no so easy to explain, because the math under it is not trivial. Fortunately, just a bit of focus miss or a less sharp lens will fix it...but only before the shot. Once you have it, the only solution in post is to paint over it."

Jeff: "When the moon hits your eye like a big pizza pie, that's a moiré."

Matthew: "'When two patterns of lines cross to form new designs, that's a moiré.' Wisdom found elsewhere, but I think of it every day."

Rob de Loe: "The sensor in the Fuji GFX 50R is quite prone to this kind of aliasing. The 'Enhance' tool in Lightroom sometimes can tidy up some of it (note the qualifiers). I tend not to see it in my files because I usually stop down far enough for diffraction to eliminate the problem. This is where the GFX 100S really cleans up: the more advanced sensor is vastly less prone to aliasing."

Comments

[Bill Tyler]

Well, highly off-topic, but speaking of dandelions, there's an interesting article I came across recently about some newly discovered aerodynamic properties of dandelion seeds. It's a quick, non-technical read. https://bgr.com/science/dandelion-seeds-wind-physics-5924018/

[scott kirkpatrick]

Moire much?

[Richard Parkin]

Dandelions are repeat flowering in U.K. if you mow them in your lawn, as most do. The leaves are edible in salad and used to be blanched in the dark like endive, whether this reduces their diuretic effect I don’t know but that folk used to eat them is evidenced by their common names in several European languages — pis-en-lit etc ;).

[MIKE MARCUS]

Thank you, Jeff, your comment made me LOL. I needed that!

[Dave]

Well, if you're going to pass off the 200% image as a fine art print, I guess you'll have some trouble.

Otherwise, now that you're aware of that problem, don't worry about it.

The thing that bugs me is the purple fringing. I never had that problem with film.

Speaking of which, I took some test shots with my 77mm Limited of tree leaves against the bright clouds and it seems as though the recent firmware update has greatly reduced the purple fringing of that lens. More testing to do, but I was pleasantly surprised.

[Kent David]

Zoom in to 500% and I bet you see aliens...

[Charlie Ewers]

You have a dandelion "problem" only if you insist on having a totally unnatural, environmentally insane, monoculture grass lawn. Otherwise, you can just think of the dandelions as beautiful, albeit short-lived, free flowers.

[DavidL]

The interference in the zoomed section could be from raw file compression. I don't know what the raw file save options are for the A6600.

[Stephen]

Forget the moire, that picture of your shed is lovely. Your walkabout snaps are always enjoyable to look at.

[Dan]

Too bad the dandelions are not in North Korea. They have a major shortage - because they are edible. A starving population eats them so fast they don't have a chance to become a nuisance.

[I've been eating them too! From a planter on the porch. The greens are very healthy. Glad I don't need greens for sustenance, though. --Mike]

[Robert Newcomb]

That test shot self portrait shows a much leaner and healthier looking person .Well done Sir!

[Thomas Mc Cann]

Last year we had a lot of dandelions and this year looked like a repeat so I spent €50 on dandelion weed killer before I gave up.

[Phil Martin]

There are a great many old recipes for dandelions, assuming they are the same variety as the UK.

[Lynn]

Looks like you've been smoking something in that shed Mike.

[Nope. Drug- and alcohol-free since 1990. I still think it must be aliens. --Mike]

[Robert Roaldi]

People want grass lawns for two reasons. One: it makes them feel like rich Victorian estate owners; but those owners had a permanent staff of gardeners, do you? Two: Grass is soft to walk on in bare feet, dandelions greens are not.

Solution: Get rid of the damn grass and plant clover. Soft to walk on, doesn't grow as tall so less maintenance, and because of the broad leaves it does a better job of weed prevention.

You know why lawns are difficult to maintain in good condition? Nature hates lawns. Why do we think we can beat nature?

[MikeR]

A dandelion-free lawn is a sign of nasty chemicals and the lawn itself is a bizarre Veblen syndrome. A lawn is a pasture that one can afford to waste, by keeping sheep off it, and using humans to mow it. I wonder how many people would prize lawns if they realized that they're just taking the place of sheep?

I like seeing fields of goldenrod in the fall, both from the ground, and from a small plane.

[John McMillin]

Spring has sprung, and that always beings out the Lawn Hippies who espouse the virtues of dandelion: color! Food for the insects! Death to the HOAs! It's a militant reaction to the Lawn Nazis who spray poisons to compel green uniformity from curb to shining curb.

Seeking some middle ground in this most pressing issue of the week, I've made a compromise. Dandelions are welcome in my lawn as long as they're a sunny yellow, but when the white seed tops develop, I bring out the mower. After cutting and bagging them, they go into the compost pile. In May, I have to do this several times per week. After that, the blooms subside until next year.

The problem with dandelions that the Lawn Hippies ignore is that they die back to the roots after frost. That leaves the ground uncovered and muddy for half a year, if I let them follow their naturally aggressive habit of spreading and displacing the grass.

As for moire, if it's a problem, just use the "AA Simulator" feature in your your Pentax camera. You all do have a Pentax, right?

[Chuck Albertson]

All together on the chorus:

Dandelion don't tell no lies
Dandelion will make you wise
Tell me if she laughs or cries
Blow away dandelion

(Courtesy of the Glimmer Twins, with Lennon and McCartney on backing vocals)

[Giuseppe Pagnoni]

Here’s simple recipe from Italy for a tasty salad: dandelion leaves (small are better), cherry tomatoes, some finely chopped fresh garlic, fresh mint leaves, extra-virgin olive oil, balsamic vinegar, salt and pepper to taste!

[Bill Skones]

An imaging system is, ideally, matched to the scene to be imaged and desired output. The problem here is, of course, that Bayer sensors are not well suited to imaging fine, regular structures like your shed vent. A Foveon or pixel shift sensor would work better. The antialias filter required to prevent moire (aliasing artifacts) for these structures with a Bayer sensor is quite strong and not needed or even desirable for most images. But the real problem is that such a strong antialias filter interferes with DXOmark resolution figures and pixel peeping, inhibiting camera sales.

[Andy Oca]

(sing) "When a grid's misaligned, with a grid close behind, that's-a Moire"

[robert e]

Sometimes it seems like moiré is digital's equivalent of rainbows. Maybe not as grand as rainbows in the sky, but the more mundane kind you see around lawn sprinklers. Or are rainbows nature's moiré?

They are different phenomena, of course, but similarly rooted in the fact that white light is comprised of colors, with one being an artifact of a particular way we reverse-engineered this natural property so that we could record and reproduce it.