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.

Friday, October 23, 2015

Digital Infrared Photography - A Brief Introduction

Daisy. Color infrared  Macro.
Infrared or ‘IR’ photography is a small but growing photographic niche that allows photographers of all abilities and budgets to expand their skills, augment their artistic vision, and create unexpected and exciting images that cannot be captured in other ways.  For the landscape photographer, IR photographs capture surreal images hallmarked by white foliage and dark skies – images that are at once familiar and unfamiliar.  With a few manipulations, the sky can be blue and the foliage can be golden, lavender, or red.  Black and white IR landscapes are striking even when the trees are bare. 
Color infrared. Lake Avalon, near Hillman Michigan.
Architectural photographers are employing IR methods because the black and white images are contrasty and they often resemble high quality architectural drawings.  Because IR light is reflected differently than full spectrum light, IR photos often reveal architectural details that are masked in visible light photography.
A growing number of wedding photographers are creating dreamy high key and IR fantasy photos as a value-added service.  Fine art photographers use infrared photography to produce unique low key studies of shape and light and portrait photographers use IR to create flattering high-key images (and some creepy images) featuring dark eyes and porcelain skin. Even macro photographers are employing IR methods to capture eye-catching images of flowers, technology, and insects. 
The reason for the growing appeal of IR photography is the widespread availability of IR-capable digital cameras. IR film was touchy, relatively expensive, and often difficult to use. The IR learning curve was steep in the film era because it could take days to realize you screwed up the shot.  With digital cameras, the “shoot, evaluate, adjust” cycle can be performed immediately after the image is captured.  Immediate feedback allows photographers to acquire knowledge and experience more quickly than they ever could when shooting IR film.  In addition, it’s cheaper to climb the learning curve with digital photography because there is no film to purchase and develop.
How do I get started?
Like any form of photography or art, your reaction to IR photography is a matter of personal taste. Some people love it; some can’t stand the “look” of an IR photograph.  I strongly urge every wannabe IR photographer to examine a wide variety of infrared photographs before they start spending money on new equipment.  Looking at a variety of IR images is not only enjoyable, but it can shorten the learning curve by allowing the neophyte to concentrate on an IR style or look they find most appealing. To get you started with IR photography, I have included some gallery links at the end of this article.
The next major thing you will need is a RAW processing program and some photo manipulation skills.  If your usual photographic style is to shoot JPGs and you are driven to “get it perfect in the camera” you may become frustrated by the IR photography experience.  With very few exceptions, most IR photographs have to be manipulated after capture. One major reason for image manipulation is white balance. Only a few older Nikon cameras are capable of accepting a custom white balance that works for IR photos. Therefore, Nikon camera users must shoot RAW images and set the white balance with external software. In addition, most IR photos are dull and flat right out of the camera and adjustments are needed to make them presentable.  The blue and green sky effects are created in post-processing. That said, LifePixel now has a hybrid filter that gives blue skies right out of the camera.
For those who are primarily interested in gear, this is where the good stuff starts. There are two primary methods for creating IR photographs - attaching an external IR cut filter to your camera lens and putting the cut filter inside the camera.  An external filter allows the photographer to use their camera for normal photography when the filter is removed.  IR conversion voids the camera’s warranty and after conversion, the camera becomes a dedicated IR camera. 
External Infrared Filter. Note that it is opaque.
External IR filters are usually a good place to start for most new IR photographers because filters are less expensive than camera conversion. External filters also have some challenges. The first challenge is that the filter is opaque to visible light and once the filter is attached, the photographer can’t compose or focus accurately through the viewfinder.  Most filter users shoot in manual mode, set their composition and focus, and then attach the filter.  The second challenge is that the filter reduces the amount of light striking the sensor by 5-7 stops.  This means that longer exposures are necessary to get a good exposure.  You can compensate for longer exposures by increasing the ISO, but that will eventually produce more sensor noise. Another major complication is that longer exposures contribute to motion blur. Photographers who use external filters will need a sturdy tripod to produce the best results. The last major challenge is setting the white balance and color rendering.  Despite these challenges, many wonderful IR photographs have been created using external filters.  External IR filters work especially well for studio work, for creating silky flowing water effects, architecture photography, and for landscape shots on a calm day.
The standard IR filter is the Wratten #89B filter which blocks 50% of the incoming light with a wavelength shorter than 720 nm. Also known as the Hoya IR72 or the Heliiopan RG720, this filter produces excellent IR photographs. Stronger filters including the Wrtten #87 (Hoya IR80 or Heliopan RC800) will eliminate 50% the light with wavelengths shorter than 800 nm are also available but the filter price is generally higher. 
Exposure times will vary depending upon the type of filter, the sensitivity of the camera sensor, the strength of the IR blocking filter in the camera, and of course, the amount of IR light. That said, exposure times usually range from 10 seconds to 120 seconds for photos taken on a sunny day.
BW infrared. Ann Arbor Michigan.
The last option for IR photography is to have a DSLR converted for exclusive IR use. This is more costly, but it produces the best results and offers the most photographic flexibility. This option involves camera disassembly and removal of the IR blocking filter that sits in front of your DSLR’s sensor. The IR blocking filter is replaced it with a filter that blocks visible and ultraviolet light.  What are the benefits to this approach? The major advantage is that you can use your DSLR just as you do today. Exposure values and shutter speeds are similar to the values used for visible light images and you won’t have to waste time prefocusing and attaching the filter before shooting. And with a converted camera, you can shoot moving objects.  As an added bonus, the conversion process removes the anti-aliasing filter that sits in front of the sensor. This can give your images a little boost in sharpness.
Foggy Footbridge - IR. Matthaei Botanical Gardens, 
The disadvantages of using a dedicated IR camera are increased cost, the inability to use the converted camera for anything other than IR photography, and voiding your DSLR’s warranty. I got around my warrantee phobia by converting an older D90 that was sitting, mostly unused, in the closet.  Once you decide to convert a DLSR, you will likely experience a bout of ‘analysis paralysis’ trying to decide which filter to have installed. This is where the Infrared Photography Forums are invaluable.  There, you can ask a group of experienced IR photographers which choice they made and why.
What About Lenses?
Here’s a conundrum that may set your Nikon Acquisition Syndrome into a tailspin - some of Nikon’s very best lenses can be total duds for infrared photography. The major problem is hot spots. A hot spot is an area in an image (usually in the center) that appears to be lighter or brighter than the rest of the image. Hotspots can also produce color shifts in the image that are difficult to remove in post processing.    
There are several reasons why hot spots occur, but the most common culprit is the black coating on the inside of the lens barrel. This coating is designed to absorb stray light and keep it from bouncing around within the lens. Lenses are designed for visible light photography and the coatings are well tested for that use. However some coatings don’t work well for IR light and the reflected light can produce a hot spot. Certain lens coatings can contribute to hot spots in the much same manner.
To confound the hot spot issue, there appear to be camera-related conditions (e.g., reflective microlenses or sensor elements) that conspire with lens designs to create hot spots when the aperture gets smaller. Camera specific contributions may be one reason why some lenses have different in hotspot reports in different lens databases.  In general, the Nikonians IR lens database provides an excellent initial resource for determining if your Nikon lens has hotspot issues.  Websites from Kolari VisionNasim Mansurov, and Bjorn Rorslett provide even more IR lens compatibility information for Nikon lenses and lenses manufactured by other companies. Some of the more popular “good performer” lenses include the Nikkor 18-55mm, the 18-200mm, and the 16-85mm VR lenses. 
Another lens challenge is focus shift.  Light bends when it passes through a lens and the amount of displacement depends upon the wavelength. Ultraviolet light bends the least while infrared light bends the most. Modern lens designs compensate for light bending and they are able to perfectly focus the middle of the spectrum on the sensor surface. Unfortunately, this means that the infrared light is back-focusing when the viewfinder says the image is in focus. Focus shift is especially problematic when wide angle lenses are used. (Wide angle lenses are the most ‘bendy’ lenses in your kit.  They generate much more focus shift than long focal length lenses.)  From a practical standpoint, this means that you have to focus on objects in front of your subject in order to get a well-focused IR image. Older lens designs with a distance scale often have a dot or bar indicating the infrared focus point for images that would normally be captured with infinity focus. When reputable IR conversion services alter a camera, they will adjust the focus calibration to compensate for focus shift. This calibration is done at a single focal length and the farther you go from that calibration point, the more focus error you will accumulate. Live View can compensate for this type of error because the focus engine uses the sensor image rather than the visible light image to control the focus. Stopping down can also compensate for some of the accumulated error by increasing the DOF. For most lenses, the best focus compensation is probably achieved at f/8 to f/11. 
Some Parting Remarks
The ability to photograph an unseen world existing just beyond our normal perceptions seems like something right out of the Twilight Zone.  However, IR photography is not an imaginary process. It’s available now and it offers exciting vistas for photographers who want to flex their creative muscles. 

Links to Infrared Photo Galleries and Discussions
Flickr Group Infrared

Flickr Group Magical Infrared

Flickr Vincent Versace IR Photos (mostly people)

Chris Maher - Fine Art Infrared Gallery

Don Ellis – IR Galleries are at the bottom of the page

Daniella - Infrared Landscapes

Dr. Kiss Ákos Zoltán– Infrared Landscapes with an external filter

LifePixel Infrared Photo Galleries

Bill Naiman Infrared & Digital Art Gallery

Kathy Cavallaro’s Infrared Gallery

Wednesday, July 22, 2015

Creating an Infrared Photo Series - Infrared Cornfields

Image 1. Color Infrared. Tractor and Disc Harrow.
A photographic series is a set of photographs with a common theme.  A photo series is often used to highlight a place, a purpose, or a condition, tell a story, evoke emotions, or document events. Images within the series are intended to be viewed both as a group and as individual photographs.

I’ve wanted to create an infrared photo series for a while because when I visit a place regularly, I see a wider range of possible images than I would normally find with a single visit. Subject familiarity also allows me to anticipate changes and challenges. 

I chose to start with an easily accessible subject, cornfields. I pass by a number of farms and fields on my way to work and the cornfields are unfenced and readily accessible from the road. This was an important decision for me because I tend to be a procrastinator.

Newly planted field. Color IR
Because I am in the area every day and the tripod is always in the car, my prep work consists of grabbing my infrared camera bag when I leave the house. My subject is close at hand so I can easily react to changes in weather and lighting conditions and it’s no great loss if I don’t take a single shot during the day.

I intend to keep photographing these fields over several years. This will give me time to refine my photographic capture techniques and post processing. My ultimate goal is to have a few unique high-quality images that have their own voice and transforms a mundane subject into something visually appealing. 
  
The purpose of this post is to share my thoughts about creating a photo series and to show some of my current images.  These images may never make it into the final mix, but they represent where I am today.  I’ll be posting more images in the future.


Image 3. Newly planted field. Color IR.
The first image shows a tractor pulling a disk harrow through the field.  The window glass in the cab is treated so it appears opaque in IR. When looking through the viewfinder (visible light view), I was able to see the driver.  Nikon D90, standard 720nm IR conversion, Nikkor 105mm f/2.8 VR, f/4, 1/1250 sec, ISO 200.

Image 2. Newly planted cornfield.  Color infrared with channel swap. The corn plants are only 1-2 inches tall. Nikon D90, standard 720nm IR conversion, Nikkor 105mm f/2.8 VR, f/10, 1/200 sec, ISO 200.

Image 3. Closer view of the tree in the newly planted cornfield.  Color infrared with channel swap. The corn plants are only 1-2 inches tall. Nikon D90, standard 720nm IR conversion, Nikkor 105mm f/2.8 VR, f/10, 1/200 sec, ISO 200.


Image 4. Young corn - Infrared. BW with Duotone overlay.
Image 4.  Short corn plants.  Duotone image.  Converted to black and white in Photoshop CS5 then converted to greyscale.  A Duotone overlay was applied.  Nikon D90, standard 720nm IR conversion, Nikkor 20mm f/2.8 AFD, f/4, 1/3200 sec, ISO 200. I should have used a smaller aperture.

Image 5.  Mature corn. No channel swap. I took this a while ago.  I captured this image with my 590nm supercolor camera. I wanted spooky shadows and contrast so I placed two flashes in the field to camera right. The first flash was fairly close to the camera and two rows over. The second flash was about 10 feet away in the next row. Used a cheapo radio trigger to activate the flashes. I shot several brackets and this was the keeper.


Image 5. Mature corn with flash. No channel swap.
I cannot tell you how strange it felt to be in a corn field on an autumn evening shooting exposure brackets with two SB800 flash units. Anyone driving by probably thought space aliens had landed. It was that kind of location. D90 IR (590nm conversion), Nikkor 20mm f/2.8 AFD, f/16, 1/160 sec, -4EV, ISO 400, handheld.

Monday, May 25, 2015

Secret IR Window Reflections

Energy-efficient windows are treated to reflect infrared wavelengths and those reflections can be photographed using an infrared camera. To demonstrate this process, I returned to the Upjohn building on the University of Michigan's East Medical Campus to photograph this curved window wall. The infrared-reflecting windows in this facade act like a giant IR mirror.

The “secret” part revolves around that fact that the IR reflections are not visible in the viewfinder. When I was taking this photo I saw desks and boxes that were pushed up against the window. The IR reflection was only visible when I looked at the back of the camera. My focus point was on one of the mullions.

For this shot, I waited until the sun went behind the clouds and started shooting. Post-processing was done in Photoshop CS5 including the conversion to black and white. I converted to grayscale and then added a slight duotone treatment.

D90 (590nm SuperColor conversion), Nikkor 20mm f/2.8 AFD, f/5.6, +1.67EV, 1/200 sec, ISO 200, handheld. 

Sunday, April 19, 2015

Springtime IR Opportunities - Capturing Immature Leaves

The weather has finally warmed up in Southeast Michigan and the leaves are just budding out. Many landscape IR photographers will tell you that there aren't enough leaves to make a good photo at this time of year. In my experience, the Spring is an excellent time to capture silhouettes (see my previous post) and small leaves against a darker branch. Some of these images can be quite dramatic. In this post I will share three images that I took yesterday. The shirtsleeve weather was a welcome respite from the bitter Michigan winter.

Infrared photo  Ornamental Crab Apple leaf buds.
The first image is a high-contrast black and white photo of leaf buds from a flowering ornamental crab apple tree. The branch was shot against a clear blue sky using matrix metering. This made the sky very dark. I noticed the light was making high contrast shadows on the leaves and the branches. The brown thing is a dried up crab apple.  Post-processing was rather simple. I set a WB in Capture NX2 and converted the image to a TIFF and worked on it using Photoshop CS5. The original image was so contrasty that I did not have to convert it to black and white. I set a black point on the background, added some contrast, toning, and sharpening to produce the image you see here.


Spring buds in IR. Domino's Farms in Ann Arbor Michigan.
The second photo is from an unknown tree I found at Domino's Farms here in Ann Arbor. I set the WB in Capture NX2 and did the rest of the processing in Photoshop. Once again, I was able to capture a high contrast image that did not need to be converted to black and white. I used the NIK Detail Extractor filter (large details) to provide more separation for the leaves. I also used a Dark Contrasts filter to increase the contrast. I did not remove the cyan coloration in the leaves appeared because it provided some visual interest. In this photo, the branches are as interesting as the buds and stamens.  


Ornamental Crab Apple leaves, Springtime. Infrared photo.
This image is also from an Ornamental Crab Apple tree taken against the blue sky. The original OOC image had a natural gradient in the background that went from black at the top to dark maroon at the bottom. the leaves were also maroon in color. The maroon coloration on the leaves resembled a duotone process so I decided to follow that path. The image was converted to Greyscale and then to Duotone using Photoshop CS5. I used Pantone 8040 C for the second duotone color. While this image isn't as dramatic as the first two images, the duotone toning brings out the light and shadow gradients.  

All of these photos were taken with a Nikon D90 (standard 720nm conversion), Nikkor 105mm f/2.8 VR lens, and ISO 200.  I used matrix metering and spot auofocus.

Hope you had a great Spring!

Tuesday, April 14, 2015

Nikon Capture NX-D: White Balance and Channel Swap

As I mentioned in my previous post, the Nikon Capture NX-D is Nikon’s new freeware replacement for the venerable Nikon Capture NX2 program.  Capture NX2 was a full-featured photo editing program created by NIK software in collaboration with Nikon.  When Google purchased NIK, the collaboration stopped and Nikon had to scramble to produce a replacement product.  The result was NX-D.  Capture NX2 is no longer supported by Nikon.

CNX2 was the workhorse program for many Nikon IR photographers because the most Nikon cameras cannot set a custom white balance for infrared light.  They just don’t have enough adjustment to white-balance these images. You can check out my white balance post for more information.

Now, let’s get to the real purpose of this post -- describing how to set a white balance and perform a channel swap using the new NX-D program. 

Step 1.  Open your RAW image in NX-D.  As you examine the user interface, you will notice that most of the editing functions are arranged on the right side of the screen.

Step 1. Open the image in NX-D.

Step 2.  Click on the WB icon on the right panel.  The WB editing panel will appear.  Click on the down arrow next to “Recorded Value” to open the white balance menu.


Step 2. White Balance.

Step 3.  Click  “Use Gray Point” located at the top of the menu then click on the Gray Point Selection Tool

Step 3 White Balance
Step 4.  The cursor will become an eyedropper and you can click on a point that should be gray in the image.  If you have included a gray card in the image, click on that.  To sample a larger area, click and drag to choose a larger area to sample.  Compared with CNX2 which could sample the entire image, the NX-D marquee is quite small.  You can use the Fine Adjustment and Tint sliders to dial in the appropriate amount of white balancing.

Step 4. White Balance
Step 5 – Channel Swap.  Click on the LCH icon on the right editing panel.  Click on the down arrow next to “Master Lightness” to pull down that menu.  Click on “Hue.”
Step 5 Channel Swap
Step 6.  Click on the down arrow next to “60 degrees” and choose “180 degrees.”  Click on the white arrow on the right side of the display and slide it upward until the sky is the color you want.

Step 6. Channel Swap
Step 7.  This is what the sky looks like when the arrow is moved upward.


Step 7. Channel Swap Complete
I usually export the image as a 16-bit TIFF file at step 5 and do the rest of my post-processing in Photoshop.  On rare occasions, I will perform a channel swap in NX-D and then export to a TIFF.  I really don’t do any photo editing in NX-D.

I hope you find this explanation helpful.



Sunday, April 5, 2015

Can NX-D replace Capture NX2 for IR Photography?

Nikon NX-D
Capture NX-D is Nikon’s new (and free) non-destructive RAW processing application for editing .NEF and .NRW files. Its predecessor, Nikon Capture NX2, has been indispensable for many Nikon IR and UV photographers because most Nikon cameras cannot establish an in-camera white balance when shooting UV and infrared images. (For more information, you can read my post describing why we need to set a white balance.) 

CNX2 was also important because it honored the in-camera Picture Controls.  Photoshop and other RAW processors cannot utilize Picture Control information and the out-of-camera images you see in Adobe Camera Raw can be quite different from what you saw on the back of the camera.

So the burning question is, “Can NX-D replace CNX2?” As a RAW processor, the answer is a qualified yes.  Yes, it honors Nikon Picture Controls. Yes, it can be used to create a channel swap and the blue-sky effect in color infrared photos. The qualification comes when we talk about setting white balances.

In CNX2, the White Balance software had a marquee function that allowed photographers to draw marquee lines around the entire image thereby creating a white balance in much the same way a camera does for visible light. NX-D also has a white balance marquee function, but the selected area (using left-click and drag) is quite small. This works well if you have something gray in the image or have a photo of gray card under the same lighting conditions. If you don’t have these things, setting the white balance can be hit or miss. Yes, you can use the levels and curves function to establish black, neutral, and white points, but I would rather use these function to fine-tune the White Balance established by the software (e.g., removing blue or cyan from clouds). 

As an image-editing program, NX-D is a pale specter of CNX2. The basic editing functions are there, but the overall utility of NX-D reflects its freeware status. I would hate to use NX-D as my primary photo editing program. The real value of NX-D is its ability to process RAW images. I plan to use CNX2 as long as possible because of the white balance limitations. However, the clock is ticking. Without support, CNX2 will become useless when I upgrade my computer operating system or decide to convert a newer camera.  

Saturday, April 4, 2015

Springtime IR Silhouettes

Springtime Silhouette - click for larger image
The calendar says it is springtime, but the Southeast Michigan landscape is still pretty bleak. For me, this is the optimum time to practice taking IR silhouettes. The skies are kicking out a lot of IR light and with a light cloud cover, the sky serves as natural softbox.

This photo shows a tree that I found alongside the road. This tree managed to hang onto some of it's leaves despite the wind, snow, and sleet that battered the landscape all winter. The photo was taken on March 23, 2015 in Pittsfield Township Michigan using a Nikon D90 (standard 720nm conversion) camera, Nikkor 105mm f/2.8 VR lens, at f/6.3, 1/160 sec, +2EV, and ISO 200. I used spot metering and metered on the tree. (I wanted the sky to blow out.)

Post-processing was done in Photoshop CS5 and Adobe Camera Raw.  The photo was converted to BW using CS5. With this approach, you don't have to worry about a channel swap.

I find lots of interesting shapes at this time of the year that I really can't photograph when the leaves are out.