Category Archives: Photography

How To Use DSLRs To Create Stereo Images

PetaPixel posted an image of David Klutho making 3D images of the Olympics.

  • You can see what looks like a two cable shutter release on top. That can be made by adding a second cable to an existing shutter release.
  • He is probably using manual settings to sync the camera settings.
  • You can see how he physically keeps the cameras held together.
  • You can also see a band in front that might be for syncing zoom.

OK, so now we know see how the Sports Illustrated 3D Pro David Klutho does it!

peta

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Multiple Shot Panoramas

(Originally posted on 2016-05-08)

We experience the world in ultra widescreen; that’s how our photos should look.

Can’t I use a wide angle lens, and crop the image to make a panorama?
You could, but you will loose a lot of
detail. Even a perfectly exposed and focused image will look grainy (or blurry), if you don’t have enough resolution.

I have a lot more to say about this, and I will mostly do so when I share my own panos. In the meantime, here’s Richard Harrington’s take, and some of my comments:
https://youtu.be/QMR6nnPoeZ4

Handheld Technique
Do this instead of bracing the camera against your chest:
1) Look through the viewfinder.
2) Use the grid lines in your viewfinder to align your images. Also use them to make sure that you have at least 33% overlap between images. This is easy to do with the 3 x 3 grid.

On Tripod Technique
The distortion created by hanging your camera off the side is very difficult to deal with. If you don’t have an L bracket, then, yes, keep your camera in landscape orientation, and use a wider angle lens.

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Lens Compression and Lens Distortion

(Originally published 2016-03-16 as /archives/10930)

This lens-compression-thing: we all agree on it correct?

Lens Compression

The definition of lens compression is this: if you use a longer focal length, then the background will appear to be closer to the subject. There are numerous examples of images that “prove” this out there (including the GIF below), but guess what? Lens compression doesn’t actually exist.

Here’s how the prove-it examples work:

  1. First the photographer makes a photo of a subject, standing in front of a background object, with a short focal length lens (wide angle, less magnification).
  2. Then the photographer takes the same picture, of the same subject, at the same distance from the camera, but with a longer focal length lens (telephoto, more magnification).
  3. Then we compare the two images, and note that the background object appears to be closer to the subject in image #2.Here’s the kicker:
  4. If we then crop image #1, so that the subject takes up the same amount of space in each image, we will note that the subject now looks to be the same exact distance from the background object as in image #2.

In other words: lens compression is just an optical illusion.

Lens distortion

Barrel Distortion, Pincushioning, Bokeh, etc., may be different with each of the two lenses. Generally the wider angle lens (shorter focal length, less magnification) will distort the image more and cause more foreshortening relative to the telephoto lens (longer focal length, more magnification), but not always. A lot depends on lens design, and post processing software is really good at removing distortion these days.

The following GIF was shared at “reddit /r/educationalgifs How different lenses affect portraits“. It shows the foreshortening issue and the so-called-lens-compression-issue at various focal lengths of a telephoto super zoom lens. For many people this will be proof that lens compression is real. It still isn’t real, and not all wide angle lenses will cause such drastic foreshortening.

OK: so if the focal length is changing, then why is the subject’s head mostly the same size? Because the photographer is moving physically closer to the subject, for the wider angle shots, and farther away for the telephoto shots.

Here’s the GIF:
XBIOEvZ - Imgur

Back to the Lens Compression Example

OK, so Paul must be wrong about lens compression. I mean look at how that tree in the background of that GIF moves closer to the subject: right?

In the following video, Dieter Schneider does the steps (from above) to prove that lens compression does not exist.

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Walkaround: Cessna Bird Dogs and Piper AE-1

(Post date: 2016-08-30.)

I usually only accept my images when they “make a good picture”. These walkarounds have a different priority. In this case it’s to get as much detail as possible for modelers: free flight, paper, RC, styrene kits, all types.

This post is for the Cessna Bird Dog and similar warbirds (including a Piper AE-1). The bird dog was most famously used in Vietnam to find targets. There were Airforce pilots in large propeller planes, and fast jets, but then there were the people that flew these tiny little airplanes at low level, while being shot at, to find targets, and downed pilots.

If you have any interest in these airplanes, or the soldiers that flew them, then you need to read Mark Berent’s books. He was there. The books are excellent.

If you would like the highest resolution versions of these copyrighted images, or prints, then please let me know, and I will upload them to Redbubble.com or 500px.com.

N3752L

Airplane Model: (1962?) Taylorcraft DCO-65
N3752L - TAYLORCRAFT DCO-65 - Left

N4763E

Airplane Model: 1951 CESSNA 305 D
Engine Type: Continental O-470 A&C65 Series
N4763E - 1951 CESSNA 305 D - Instrument Panel

N3044L

Airplane Model: Piper AE-1 (1942 Piper J5C)
Engine Type: Lycoming O-235-C

This one’s an ambulance (with a mannequin in it). To see what the ambulance looks like with the top closed, see the background of the first N50573 image below.

The bird dogs are related to the Cessna 170, this one’s related to the Piper J5 Cub.
N3044L - 1942 PIPER J5C - Ambulance

N50573

Airplane Model: 1942 Taylorcraft DCO-65
Engine Type: Continental A&C65 Series
N50573 - 1942 TAYLORCRAFT DCO-65 - Birddog - Right

N50573 - 1942 TAYLORCRAFT DCO-65 - Birddog - Front and Filter

N50573 - TAYLORCRAFT DCO-65 - Left Distance

N50573 - 1942 TAYLORCRAFT DCO-65 - Birddog - Left

 

 

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How To Shoot Fireworks

(Originally posted on 2016-07-06)

This is why you should use a camera with a bulb setting. You open the shutter when you hear the first pop, and close it when the light dims to get something like this:

005167
© 2013, Paul Danger Kile, All Rights Reserved

In this video Richard Harrington tells us how to shoot fireworks (for Macphun):

This infographic covers the same information (below):

By Richard Harrington, and Macphun.

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“The Dress” (The Only 100% Accurate Explanation)

(Originally written in February of 2015 as /archives/date/2015/02)

tumblr_nkcjuq8Tdr1tnacy1o1_500
The original image.

Would black look gold without an optical illusion?

Some are saying that it’s a color constancy illusion. I will attempt to prove that’s not the case.

Bleached-blue could look white, and bleached-black could look golden-brown.

Each pixel may have a different color, but Photoshop’s color picker can do a 51 x 51 pixel average for us to get a more accurate estimate. In this version of the image, the golden section of the darker-colored stripes’ RGB values are:

  • Red: 121
  • Green: 106
  • Blue: 71

These values are like “shadow”, which is a golden brown. If our perception matches the actual technical colors, then we are not dealing with an optical illusion.

Why are the colors wrong?

Here is where the real problem lies:

Most people say that it’s white and gold.

tumblr_nkcjuq8Tdr1tnacy1o1_500
The original image.

On Buzzfeed 68% say “white and gold”, and 32% say “black and blue”.

Color Calibration?

Monitors are not color calibrated from the factory, so many people are not seeing accurate color.

Was the image white balanced?

We would hope to find white balance information in the image’s EXIF, but it’s not there. So how do we white balance this image? The dress in the background looks white and black. I loaded the image up in Lightroom, and used that assumption to white balance it. If you would like to try this out yourself, here’s how to do it. The black I used is in the lower left corner. We can all agree-that that’s supposed be black: correct? 🙂

With the white balance "fixed".
With the white balance “fixed”.

Is the image accurately toned?

Lightroom shows us that we might have blown out colors. How do we know that this is real clipping, instead of a false positive? The light has softened the edges of the dress so much that it looks foggy in there. So, yes, this a blown out image. If we were there, then we would have a well-exposed the image, but we weren’t, so we are going to adjust tone to even out the histogram.

With the tone "fixed".
With the tone “fixed”.

So what is our best guess for the color? Black and Blue

Each pixel may have a different color, but Photoshop’s color picker can do a 51 x 51 pixel average for us to get a more accurate estimate.

The lighter colored stripes have a lot of blue:

  • Red: 8
  • Green: 77
  • Blue: 206

In other words: blue.

The darker colored stripes RGB values are close to zero:

  • Red: 1
  • Green: 8
  • Blue: 49

In other words: black.

Conclusion

A skilled photographer would could set its white balance and its tone. Once we do that, it’s blue and black. Here’s the final word:

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