Saturday, December 3, 2016

Inverting an Infrared Image to Produce a Different Look

Sometimes you want to change the look of a photograph or just try something new. Inverting the image is an interesting way to do that, especially if you want a high contrast final image. For this post, I am going to start with an infrared photograph of Christmas tree ornaments taken with a Nikon D90 with a supercolor (590nm) conversion. 
Click for larger image
Figure 1. Original IR image.

This image was taken at Matthaei Botanical Gardens in Ann Arbor, Michigan. They had a number of trees in the greenhouse that were decorated by various businesses. This tree had some interesting wooden spoons that looked like people.

The original image was interesting, but it had relatively low contrast and the overall feeling was 'meh.'  I wanted to add a bit more drama to the image. Hence, the inversion process.

A simple inversion of this image using Layer > Adjustments > Invert or a simple inversion adjustment layer (my preference), would give you a blue image that looks like this (Figure 2).
Figure 2. Simple inversion of the original image

While that might be an interesting starting point for some images, my goal was is to create a contrasty black and white image. To do that, I used two adjustment layers - a black and white adjustment layer and an invert layer. 

More specifically, I 
1.  Hit CTRL-J (CMD-J for a Mac) to duplicate the background then I turned off the original layer
2.  Added the BW adjustment layer
3.  Added the Invert adjustment layer

The layer stack is shown in Figure 3.
Figure 3 . Layer stack for inversion.

At this point, the image will look a little strange but much of that can be ironed out by returning to the Black and White adjustment layer and moving the sliders to get an image that looks more like a film negative.  

From there it's a matter of giving the image more contrast and cleaning up some of the ugly bits that occur during the inversion process.  

For example, I used a white brush on the spoon in layer 1 to make the spoon uniformly dark and I used the same technique to even out the inverted hotspot on the bulb ornament.

After that, I used normal processing techniques to address brightness, contrast, levels, etc. and to make the image reflect my artistic aesthetic



The final image is shown in Figure 4.
Figure 4. Final Inverted image.

Please let me know if you found this post helpful..

Happy IR processing!

Sunday, June 19, 2016

Using IR to Create Stunning Low Contrast Images

In a recent photo challenge, we were asked to produce a wall-worthy low contrast image.  While this type of challenge brings to mind images of fog-shrouded paths and shorelines, the first thing I did was to grab my infrared-converted camera for some tone-on-tone work.  More on that later.

So, what is contrast?  Simply put, contrast is the degree of difference between the lightest and darkest parts of your photo.  More difference means more contrast.  More contrast also means that the image is more dynamic and it appears to be sharper.  With low contrast photos, there is much less difference between the dark and light tones. 

Low-contrast photography isn’t everyone’s cup of tea. Our mind instinctively wants to understand the scene and it becomes frustrated and uncomfortable when objects cannot be distinguished clearly.  In a foggy shoreline scene, we naturally try to see through the fog to discern what’s really there.  This is desire may be hard-coded into us by our prehistoric ancestors who could encounter something large and hungry in the mist. 

Let’s set aside the fog photos for a moment and think about what low contrast really means and doesn’t mean.  Low contrast doesn’t mean lacking in contrast, blurry, or flat—it means that the tonal differences are subtle.  Subtle differences in color and tone can be visually evocative and sometimes, even peaceful.  Some low contrast images can have a fantasy look to them.

Why did I grab my IR (720 nm standard conversion) camera for this challenge?  IR photography is, by definition, a low contrast medium.  We purposely block out much of the color information thereby limiting the color tones.  While we have the full range of light and dark values, these can be easily manipulated during the capture. 

Here’s the first example, buds from a shrub.  The buds were shot against the grass which turned out white in IR, giving us the white-on-white tone.  This photo was a challenge for me because I wanted to crank up the contrast and structure.  It's now a favorite because it went against all of my photographic instincts.

Shrub bud tone-on-tone IR image
Shrub bud in infrared with grass background.
D90 (720nm conversion), Nikkor 105mm f/2.8 VR, f/14, 1/60 sec, -0.67 EV, ISO 200, hand held. No channel swap.

The second example is a photo of a chive blossom.  Illumination was from an incandescent light to camera right.  I used the LifePixel preset white balance then adjusted it in Nikon CNX using the maquee funciton.  Did a channel swap in Photoshop CS5 to get the white colors. Didn't have to do much to make this image work except for shooting multiple images and decreasing the EV until the histogram fit. This is a single image.

IR Chive Blossom
Chive blossom in infrared, 

D90IR (720nm), Nikkor 105mm f/2.8 VR, f/8, 1/20 sec, -2.33 EV, ISO 200, with tripod. taken under an incandescent lamp. 


By thinking more low-contrast, you can open yourself up to much more dreamy, romantic photography that's a little more subtle and a bit more ethereal. There's a delicacy, and fragility to low-contrast photography that shouldn't be dismissed.