Vision and Perception

Ted Talks has some extremely good discussions that relate to photography.  One of my favorite videos there is by Beau Lotto and has to do with how we, as  humans, perceive color.  We are incapable of visualizing absolute color values, everything that we see is contextual.

Beau demonstrates how our brain compensates for color casts and changes in luminosity to make us see what we expect versus what is actually in front of us.  It can be frightening to see how easily the brain is convinced that we are seeing the same color when they are drastically different hues, or different tones when they are exactly the same.

The video is as fun as it is educational.

Judging at Loudoun Photo Club

You know that feeling you get in your gut when you enter your first photo club competition?  The knot in your stomach hearing the judge describe the out-of-focus foreground and the glaring, blown out hotspot? The frustration as the judge promptly throws your image out of the competition?  Well this month that guy is going to be me at the Loudoun Photo Club in Ashburn, Virginia.

Toward the end of last year I was invited to judge at the Loudoun Photo Club on March 28th for their themed competition Macro and Close-up.  I was pleased to see that they had added “Close-up” to the theme, since too few people have the actual gear to do macro work.

Technically macro means 1:1 to 10:1 in relation of the image on the sensor to the subject size.  To achieve this a lens must be capable of focusing extremely closely, or you can use a wide angle lens and a reversing ring.  Most photographers I know don’t have either in their camera bags.

Anyway, if you want to come hear me critique some images, I should be at The George Washington University Virginia Campus in Ashburn, VA at 7:00 pm on March 28th.

Why We Should Care About Bit Depth

Bit-Depth ChartI see lots of questions about image bit depth, specifically about what is the “right” number of bits to use when capturing, editing and printing. And frankly, as far as I am concerned there is no one size fits all answer to this question.  As a general rule I like to use the largest color space possible (most number of bits), which means shooting Raw with loss less compression (12 or 14-bits in most cases), editing in 32-bit color spaces and printing/digital display in 8-bit.  In some ways Lightroom has made this easier on photographers by eliminating those questions of color space and using a 32-bit color space by default, then exporting to 8-bit.

To give you an idea why we, as photographers, should care about bit depth and always use the largest color space available I created this dramatization at the right.  This shows a gradient from pure black to pure red at varying numbers of bits.  The left column is 1-bit, where there are only two possible values.  Next to that is 2-bits, where 4 (22) colors are possible.  Next to that is 4-bits, where 16 (42) colors are possible, followed by 8-bits, where 256 (82) colors are possible.

The problem comes when you change an image from 8-bits to 4-bits, you get only 16 colors.  The 256 colors can never be recovered.  No matter how many adjustments, using whatever tools, you can never get those smooth gradations of color back into the image, and as you apply strong adjustments on an image that has been reduced, those smooth gradients turn into stronger contrasts.

Strong Levels AdjustmentIn this image, I took the upper half of the 4-bit color and applied an exceptionally strong levels adjustment, moving the black point to 127.  Rather than smoothly adjusting the color into 16 hues again, you get only 8 hues, just with stronger differences between each of the bands of color.

So if we ultimately print in 8-bit color spaces, why do we bother capturing and editing in larger color spaces?  Because capturing and editing in these large color spaces allows us to maintain the smoothest color transitions possible up until the final output.

It doesn’t really matter if you understand the science (or really mathematics) behind why to choose a specific color space, as long as you understand that using the largest available color space at each step will produce the best results, and that it is best to save a copy of the image in the larger color spaces as your “master” file, since it contains the most detailed information about the image.

Abstract Photography

Image of Composition VIII by Wassily Kandinsky
Composition VIII – Wassily Kandinsky

For the longest time I had no appreciation for abstract art.  I could not understand what it was that people saw in it.  Certainly I was familiar with and even liked Wassily Kandinsky’s Composition VIII pictured above, but it didn’t have any real meaning for me.  I could not understand it.

Over the years my wife, a trained graphic artist and now high school science teacher, would try to convince me that I did not need to like something just because it was a “famous” piece of art.  And that just because I liked something, didn’t mean that I actually had to understand “why” I liked it.  It was OK to just appreciate the work that I liked and ignore the work that I didn’t.

CRW_1272_cropWith that foundation laid, when I met Joe Miller and was able to spend some time discussing photography, and that led to Joe’s preferred subject matter, abstract photography.  Joe was very patient with me, spending lots of time describing how lines, shapes, colors, textures and perspective all affect the way that we perceive a scene.  He spent a great deal of time explaining how Dave Carter, Joe’s longtime friend whom I met briefly before he passed away, would apply the psychological implications of visual design to his critiques of images.  Joe encouraged me to explore design-based, rather than subject-based, photography in a Portfolio Project for NVPS, for which I decided to work with the stained glass windows in Joe’s studio, but took all of the photographs in InfraRed using my converted Canon 10D.  The lack of color forced me to concentrate on the lines, tones and textures of the glass, however with the IR camera I got unexpected (for me) results.  Blues became translucent and bright, while reds became opaque and dark, frequently pure black.

All of this helped me to develop not only an appreciation of abstracts, but a greater appreciation of images in general.  It greatly improved my ability to abstract an image into its component shapes, which has improved my visual design.  I now find that I am framing images based on principles of visual design, even when I am shooting sporting events.

Happy New Year!

rockville_car_show_2010_0460Happy new year to everyone.  Since this is a new blog, I suspect that no one is watching, but I’ll post anyway.  I’m really happy to be starting a new year with a new website, blog included.

The car? This 1955 Ferrari 500 Mondial belongs to Rear Admiral (Ret.) Robert Phillips.  I had the pleasure of taking some pictures of it at the Rockville Antique and Classic Car Show in 2011.  Here it is in front of the Glenview Mansion where the show is held.

Strobist

David Hobby is a local(ish) photographer in my area whom I find to be extremely talented.  Having read his Strobist site, subscribed to his blog and watched his “Lighting in Layers” DVD series, I learned a great deal about working with small hotshoe flashes.

DCH_1791

I very much enjoyed the Flash Bus Tour that he did along with Joe McNally.

NVPS Competition Upload Preset

This Lightroom Export preset will export images at the best resolution for a 1400 x 1050 projector.  It applies “Screen” sharpening to the image as it exports.

Use NVPS Competition Preset

We have saved a Lightroom Export preset that automatically configures settings for NVPS competitions. This should simplify the process of defining all of the correct export settings. You can download this preset at NVPS Competition.lrtemplate.

Installing the LR Export Preset

After downloading the NVPS Competition.lrtemplate file, copy the file to the following directory based on your operating system

  • Windows XP: C:\Documents and Settings\username\Application Data\Adobe\Lightroom\Export Presets\User Presets
  • Windows Vista: C:\Users\username\AppData\Roaming\Adobe\Lightroom\Export Presets\User Presets
  • Mac OS X: /Library/Application Support/Adobe/Lightroom/Export Presets/User Presets

Applying the LR Export Preset

Select the image(s) to be resized, then select File, and Export. When the Export dialog opens, select NVPS Competition under User Presets in the Preset section of the Export dialog. This will automatically apply the appropriate competition settings.Press the Export button and a Windows Explorer window (or Finder window on the Mac) should open with the resized images in it.

Painting with Light and Shadow

Gordon Campey referred me to an article by Mark Johnson that is in the Member’s area of the NAPP website that deals with painting light and shadow onto an image to give it more depth.  When combined with the Orton Effect, it can make that technique even more interesting.

With some input from Gordon I created a Painting with Light and Shadow action set.  I’ve got two actions in the set, one that simply creates a layer to lighten and layer to darken the images.  Select the layer mask of the appropriate layer and paint with White on that mask to lighten or darken an area of the image.

Not the greatest example, but I had this shot of a fender from a tricycle:

QG0F9953-Edit_pwl_800

To add some depth and contrast into this image, I applied the Paint with Light action, and painted Light onto the yellow areas and Shadow onto the blue, red and black areas.

QG0F9953-Edit_pwl_800

You can see how much darker and more saturated the reds and blues are, and the yellow becomes more yellow and less orange.

The Paint with Light action simply creates a layer with a Screen blend mode (makes things lighter) and a Multiply mode (makes things darker).  The layer masks are filled with black, so they do not apply any affect to the image.  By selecting the layer mask and painting with a soft brush with White, it will reveal some of the lighter color underneath.  I’ve seen a number of people use brushes with differing opacities, but I personally like a very low opacity, in the range of 20 – 30%.

I normally paint in Light first, then follow that up with Shadow, but a different approach may work for you.

I thought that I would show this one again, using this alternative to the Orton Effect technique from my earlier post.

freeman_wed_0181-Edit

To this one:

freeman_wed_0181-pwl_800

This action creates a blur layer, then adds a single Levels layer that will probably require adjustment in terms of both the White point and the mid-point sliders to achieve the desired neutral effect.  It creates the same Paint with Light and Paint with Shadow layers as the above action, and the same adjustments should be applied here.

In this image I needed to lighten the trees in the background, and darken the barn and the foreground bushes and flowers.

Post Processing Adjustments

After running the Overlay and Orton Effect actions that I have created, there are still a number of adjustments that need to be made before the images are complete.

When I created the actions, I inserted some Levels layers that brighten each layer about 1 f/Stop.  This is a simple estimate and may not work well at all for a given image.

Take this image, which is pretty bright

overlay-1_main

I wanted to add some texture, so I added this cracked paint to give it a more worn feel:

overlay-1_texture

When I ran the Overlay action, it created a composite that looks like this:

overlay-1_raw

This adds the feel, but the color saturation is off and the strength of the texture is really more harsh than I wanted.  The action set the following levels:

overall_levels_default

Overall Levels

texture_levels_default

Texture Levels

background_adjust

Background Levels

So starting at the Background Levels, I started making adjustments.  Because I wanted more saturated color, I wanted to darken the Background Layer.  Moving the mid-point slider (grey triangle) to the right (lower numbers) will darken the image.

overlay-1_raw

 

background_adjust

Adjusting the Background Levels layer to a mid-point of 1.16 gives me slightly richer colors.

Next I make an adjustment to the Texture Levels to lighten the mid-point so that it will soften the texture a little.

overlay-1_text_adjust

 

texture_adjust

Moving the mid-point slider up to 1.89 lightens the texture and makes the effect just a little bit softer than the default.  The image is getting closer to where I want it, but it is just a little bit lighter than I wanted.

overlay-1_final

 

overall_adjust

Then slightly darkening the Overall Levels by moving the mid-point slider down to 0.94 and resetting the white-point slider to 229 finalizes the image for me.

The changes that I made in this image are pretty minor, but the end result is significantly better in my opinion.  The point is that some adjustment is not only desirable, but necessary.  The actions do not necessarily produce a finished image, but they significantly reduce the amount of work that you have to do with each image.