Adding Form to Backlit Photos (Intermediate)

I love backlit photos, even though some people think backlighting is overused. When the backlighting comes from sunlight, one issue is that the face is almost always illuminated by shade, which is a very soft but very flat light source (because it's omnidirectional). Sample:

If on-axis fill light is added (e.g. from a popup flash), the shaded face will be lifted, but the form looks just as flat because of the direction of the fill light. Sample:



A backlit photo can easily be made to appear more three-dimensional by lighting the face at an angle, whether using a reflector or flash.  The light can be bright enough to act as a key light, as in this sample:

(bare SB-800 flash from above and camera right, zoomed to 105mm, triggered via CLS AWL*)
*Nikon Creative Lighting System - Advanced Wireless Lighting 
Note that there is a shadow on the right side of the face (camera left), making the face look more three-dimensional than in the sample photos above.

Alternatively, the light can have a lower intensity, at an angle opposite to the backlight, to simulate the backlight bouncing off from the ground to illuminate the face.  Sample:

(SB-800 with shoot-through on camera right, triggered via AWL)

The sample photo at the top of this post is somewhere in between the two foregoing approaches.  I underexposed the ambient light, then added light from a bare SB-800 camera left and additional fill from the pop-up.  No light modifiers were used, nor did I use any postprocessing (other than conversion from RAW to JPEG) but the light doesn't look harsh due to the controlled contrast.  That's a technique I'll discuss in a future post.

How to Avoid Reflections on Eyeglasses (Intermediate)

Flash and other reflections on eyeglasses can be distracting, especially if they obscure the subject's eyes.  Here are suggestions for avoiding flash reflections on eyeglasses:

1. Use a lens with a longer focal length if possible.

2. Position the light.
a. If the flash is on the camera (e.g. popup flash), then use a three-quarters view of the subject instead of a frontal view. 
b. If the flash is off-camera and the subject is at a three-quarters view, then use on-camera flash OR put the light just a bit to side of the camera, or behind and to the side of the subject.

3. Try having the subject's eyeglasses tilted downward, or have the light at a higher (or lower) angle to the subject (instead of eye level).

Unfortunately, there's no simple rule of thumb that works all the time, therefore the foregoing suggestions are admittedly kind of vague, which is why I suggest understanding the science behind the suggestions (below) in order to determine the exact suggestions that will work for your particular situation.

THE SCIENCE BEHIND THE SUGGESTIONS:
If the light is within a certain zone relative to the reflecting surface and the camera, the light will be visible as a reflection in the picture.  That zone is called the "family of angles" and varies depending on the 1) width, 2) positions, and 3) angles of the A) light, B) the reflecting surface, and C) the camera.

To identify the family of angles, you need to do a diagram.
1. Draw the camera and the eyeglasses (which can be represented by a short line).
2. Draw a line from the camera to the left edge of the eyeglasses.
3. Draw the reflection from the line in step 2.
4. Draw a line from the flash to the right edge of the eyeglasses.
5. Draw the reflection from the line in step 4.

If the flash or other light source is between the lines in step 3 and step 5, then the reflection will be visible in the shot.  If the flash is not in between those lines, the reflection will not be visible in the shot.

In the diagrams below, the blue bar represents the eyeglasses. The dotted blue lines are imaginary lines perpendicular to the edges of the eyeglasses.  The green lines represent the lines in steps 2 and 4.  The red lines represent the lines in steps 3 and 5.

In the top left diagram, a camera with on-camera flash is squarely facing the subject's eyeglasses.  The on-camera flash is in between the red lines, thus the flash reflection will be visible (symbolized by the yellow color).
In the top middle diagram, the flash is off-camera.  The flash is not in between the red lines, thus the flash reflection will not be visible (symbolized by the white color). 
In the top right diagram, the flash is off-camera, in the same exact position, but a wide lens is used instead, creating a wider family of angles.  Although the position of the eyeglasses and the flash haven't moved, the flash reflection is now between the red lines and will be visible.
In the bottom diagram, the subject is facing a three-quarters view.  An on-camera flash will not have a visible reflection.  An off-camera flash might not have a visible reflection if it is not too far off to the side.  If the off-camera flash however, is placed far enough to the side, it will become visible.  With a larger light source (such as a softbox, umbrella, or bounced flash) there is a higher chance for at least a portion of the light source to be within the family of angles.

In analyzing the family of angles, don't forget to consider that the family of angles is three dimensional.  A flash reflection that might otherwise be visible may be avoided by having the eyeglasses tilt up or tilt down, or by putting the light source sufficiently above or below the plane of the eyeglasses.

WHAT ABOUT OTHER REFLECTIONS?
Although the foregoing assume a flash or other light source as the source of the reflection to be avoided, the same process can be used to avoid any other reflection with one difference - you can also cover an object as another way of avoiding reflections.  As long as the cover is dark and not shiny, its reflection won't show up! :)

SAMPLE SHOTS:
In the shots below, I used a Tamron 18-250 on a Pentax K100D, at 250mm (around 375mm equivalent).  Because of the long focal length, there was only a narrow family of angles.  Although I used a large light source (flash bounced above and to the front of the subjects), the reflection wasn't visible in the eyeglasses. 

In this shot I used an on-camera flash, but the subject was looking away from the camera, therefore the flash reflection was not visible, as in the fourth example above.

OTHER RESOURCES
Reflections (among other things) are discussed in detail in Light: Science and Magic, a lighting classic and a must-read for product photography.  See also this related post about reflections in aquariums and exhibits.

Search for a second flash (Intermediate)

To give myself more creative lighting possibilities, I've been thinking about getting a second flash.  I'd like to use the second flash for "special effects" like lighting the background, adding rim light, etc.

There's a philosophy that artificial light (generally flash) should simulate natural light, and there's only one natural light source - the sun - therefore we should need only one flash.  Indeed, in some of Dean Collins' portraits ( http://www.software-cinema.com/training/photography/dean-collins/4/the-best-of-dean-collins-on-lighting ), he uses only one flash, although he masterfully uses several diffusion panels and reflectors to allow one flash to accomplish multiple functions simultaneously.

However, I think the foregoing philosophy about needing only one flash is an oversimplification.  First, the philosophy neglects the fact that the flash is far weaker than the sun.  It's not like you can put just one flash outside your house to send light in through all windows.  Secondly, it's not true that there's only one "natural" light source.  Outdoors, besides the sun, we have the light from the sky itself. Open light is a beautiful light source when properly used. Indoors, there are many situations where there are multiple light sources, as when there are multiple windows.  Third, I think using multiple flashes is not so different from using panels and reflectors, except that it's more portable and you can have more control. Fourth, most photographers don't have to limit ourselves to a natural appearance (photojournalists and documentary photographers excluded)  - we are free to create an unrealstic image to match our artistic vision.

Going back to the second flash, my requirements are:
1. The second flash doesn't need TTL, and in fact manual mode would arguably be more useful than TTL because when it comes to special effects, there is far more latitude and room for interpretation.  I like this quote by strobist.com's David Hobby:
"I think of [rim lights] as being a little like pizza: When they are good, they're good. But when they are bad -- well, they're still pretty good." http://strobist.blogspot.com/2010/06/upgrade-your-rims.html
2. My plan is to use the pop-up flash to command my SB-800 as a CLS AWL slave, and trigger the second flash either with an ebay radio trigger (if it doesn't interfere with CLS) or optically in sync with the SB-800 which I will control.  In the latter case, it would be great if the flash could ignore the TTL and CLS pre-flashes.

I'm really annoyed that Nikon discontinued the SB-800 and priced the SB-900 way too high (I think they were copying Canon's pricing model). I thought about getting an SB-600 and researched third-party flashes. 

The chart below shows some of the alternatives for Nikon cameras, and what you are getting for your money.  The chart is organized into two broad categories based on power: "entry level" and "high power". I don't want to mislead though -- there's only slightly less than 1 stop difference between the entry level models and the high power models.  Explanation of the terms:

• GN: guide number, a measure of power. Because manufacturers inflate their GN, I only included tested guide numbers at 100 ISO.
• Zoom: whether the flash can be zoomed. This is useful not only for efficiently filling the frame with flash, but also important for creative purposes.
• CLS AWL: Nikon Creative Lighting System  - Advanced Wireless Lighting. Allows remote adjustment of slave flashes in TTL or manual mode or auto mode through preflashes from a commander flash.
• Digital optical slave: an optical slave that can ignore preflashes.  Normal optical slaves can often be triggered even by the TTL preflashes, dumping their light before the shutter actually opens.  Digital optical slaves ignore preflashes or use a delay mechanism to release their light when the shutter has opened.  For my purpose, I need the digital optical slave to be able to ignore not just the TTL preflashes but also the CLS AWL preflash commands to the SB-800.
• HSS: high speed sync.  Allows the flash to be used in shutter speeds faster than the camera's sync speed.  This is useful for allowing wider apertures in bright conditions.  A substitute for this is an ND filter (which is in fact more efficient - see here).
• HSS slave: high speed sync slave.  Nikon's AWL allows slave flashes to function in HSS mode (a feature not available with Canon).

ENTRY LEVEL (competes with SB-600)

a. Manual + optical slave:
YN-460 II ($46)
Real GN: 22m See http://www.flickr.com/groups/strobist/discuss/72157624180121385/ (tested at 1m) or 23m - http://www.flickr.com/groups/yongnuo/discuss/72157620880376984/72157620930372772/
Zoom: No. --> possible deal breaker
TTL: No.
Manual: Yes
CLS AWL: No
Digital optical slave: Yes. Usually compatible with CLS.  See http://www.flickr.com/groups/strobist/discuss/72157623646899772/72157623536303845/
caution: slave sensor is in the flash head, has issues triggering in sunlight.

b. Same as YN-460II but loses optical slave, and adds TTL:
YN-465 ($90)
Real GN: same as YN-460, i.e. 22m
Zoom: No.  --> possible deal breaker
TTL: Yes.
Manual: Yes.
CLS AWL: No
Digital optical slave: No.  --> deal breaker

c. Same as YN-460II + TTL + zoom:
Nissin Di622 ($169)
Real GN: ?? Less than SB-600. http://forum.lowyat.net/topic/1140175
Zoom: Yes.
TTL: Yes.
Manual: Yes
CLS AWL: No
Digital optical slave: Yes.  Advertised as compatible with CLS but cannot be adjusted remotely by the commander flash.

d. Similar to Di622 without optical slave, adds CLS AWL + HSS + HSS slave:
Nikon SB-600 ($220 new, $180 refurb through jr.com)
Real GN: 1/3 stop more than YN-460, i.e. ~25m @ 35mm.  See http://speedlights.net/2010/05/21/yongnuo-flash-guide-numbers/
Zoom: Yes (to 85mm).
TTL: Yes.
Manual: Yes
CLS AWL: Yes.
Digital optical slave: No.
HSS on remote: Yes.


HIGH POWER (competes with SB-900)

a. Manual + optical slave + zoom:
YN-560 ($85)
Real GN: 32m (45m @ 105mm zoom).  See http://www.flickr.com/groups/strobist/discuss/72157624180121385/  see http://www.flickr.com/groups/strobist/discuss/72157624180121385/72157624475116401/ (tested at 1m); see also http://www.lightingrumours.com/yongnuo-yn-560-first-impressions-427
Zoom: Yes.
TTL: No.
Manual: Yes
CLS AWL: No
Digital optical slave: Yes. Will ignore CLS preflashes. See http://www.flickr.com/groups/strobist/discuss/72157624180121385/72157624196263437/
HSS on remote: No.
*additional benefit: 2-second recycling time at full power.

b. same as YN560 features + miniplug sync:
Lumopro LP160 ($160)
Real GN: "similar to SB-900"
Zoom: Yes.
TTL: No.
Manual: Yes
CLS AWL: No.
Digital optical slave: Yes.
HSS on remote: No.

c. same as YN560 features + TTL + CLS AWL + HSS:
Nissin Di866 ($300)
Real GN: 34m (39m @ 105mm zoom) See http://www.dpanswers.com/content/rev_nissin_di866.php
Zoom: Yes.
TTL: Yes.
Manual: Yes
CLS AWL: Yes (commander or slave)
Digital optical slave: No.
HSS on remote: No.

d. same as Di866 + HSS slave:
Nikon SB-800 (~ $300 used)
Real GN: 36m (45m @ 105mm zoom) See dpanswers.com/content/rev_nissin_di866.php
Zoom: Yes (to 105mm).
TTL: Yes.
Manual: Yes
CLS AWL: Yes.
Digital optical slave: No.
HSS on remote: Yes.

e. same as SB-800 + 360-degree swivel, better interface:
Nikon SB-900 ($440)
Real GN: ??
Zoom: Yes (to 200mm).
TTL: Yes.
Manual: Yes
CLS AWL: Yes (commander or slave)
Digital optical slave: No.
HSS on remote: Yes.


WHAT I CHOSE
I really wanted the SB-600 because of the remote adjustment through CLS.  However, in many of the shots I've seen that I'd like to emulate, the photographers used very powerful strobes such as the White Lightning X1600. 

For some perspective, the White Lightning X1600 has a guide number of 450 ft. (ISO 100) when used with an 11-inch reflector. In other words, at a distance of 10 feet, the aperture is f/45.  Based on the Sunny 16 rule of thumb, bright sunlight is f/16 at 1/125 at ISO 100, or equivalent to f/11 at 1/250 (the D300 sync speed) at ISO 100.  f/45 is 4 full stops smaller than f/11.  In other words, even with the flash 10 feet away, you can underexpose bright sunlight by 4 stops.  In fact, even with a medium softbox, it's rated at f/22 - f/32 (with the softbox 10 feet away!), which is 2-3 stops more powerful than bright sunlight if you're at 1/250 sync speed. 

What I don't like about the X1600 and studio flashes is that they need a portable power source or a power outlet, and they're much heavier and bulkier than hotshoe flashes.  I just can't imagine bringing one around on vacations.

If I were to have any chance of achieving anywhere close to the same look as a studio flash, I thought I would need the most power I could get.  Considering the flashes in the high power category, the YN560 seems to offer the most bang for the buck.  In fact, it even offers a bit more light for your money than an Alien Bees B1600.  A B1600 has a guide number of 220 feet or 67 meters (with a 7-inch reflector).  The YN-560 has a real guide number of 32 meters (at 35mm zoom).  The difference between them is slightly more than 2 stops.  In other words, four YN-560s is equivalent to one B1600 (with a 7-inch reflector).  At a cost of about $85 apiece, four YN-560s is a bit less than one B1600, even without considering the cost of the $300 battery pack for the B1600.

What about the YN-460 II?  It costs about half as much as the YN-560 with about 1 stop less power.  Wouldn't having two YN-460 II's be more versatile than one YN-560?  Yes, however, I had read that the YN-560 had a much more reliable optical trigger, plus I wanted the zooming function.  Those benefits were enough to convince me to get the YN-560 instead of two YN-460 II's.

As for the lack of remote adjustment, I figured I would only need the YN560 for setup shots.  The incremental time needed to adjust the YN560 manually is not such a big deal for a setup shot.  I also plan to use the YN560 together with the SB-800 to act as one light source when I need power.  Again, in such a situation I wouldn't need remote adjustment -  I would simply put the YN-560 at full power.

I ordered the YN560 through ebay (the only place it's available at the time of this writing).  Hopefully it won't take too long to arrive and that it doesn't disappoint.  I'll test it (especially whether it can function with the CLS) and post some sample shots when it arrives.

Update:  first impressions here

RELATED POSTS:
Second Search for Second Flash

Illuminating a Room (Intermediate)

My wife and I made our bed, and we laughed at how the bed would not look as nice next time.  So I decided to take a photo of it.  In the back of my mind were restaurant photos I had seen recently, like the ones here: http://www.bellagio.com/restaurants/michael-mina.aspx . It seemed like there were pools of light everywhere.

I tried to duplicate the look by using the flash on zoomed mode at 105mm (off-camera), but the effect was nowhere near as magical.  Here (one of several attempts) the light was in front of the bed, mounted on a tripod aimed at the pillows.

After thinking about it for a while, I thought one way to get the look of those restaurant photos was to use light painting (using a very slow shutter speed, then using a continuous source of light such as a flashlight to paint parts of the scene).  The only flashlight I could find was a weak LED flashlight. I wanted some ambient light in the image, and the flashlight was barely brighter than the ambient light.  I finally decided to use the SB-800's modeling light, which was perfect for the job in terms of light intensity.  To further enhance the lighting, I turned on the light in our bathroom to serve as the motivating light for the 'spotlight' on the pillows (i.e., the apparent logical source of light).

This was the shot I liked best.  Exposure was ISO 200, f/16, 6 secs.  Ambient was intentionally underexposed about 2 stops.  With one hand, I aimed the flashlight at the pillows, while my other hand used the SB-800's modeling light to blast light here and there.

I added some local tone mapping, and did some quick cloning to remove the visible flash. The final result was the shot above.  It looks ok to me in terms of lighting, though my cheap tripod couldn't keep the camera steady enough hence the blurriness.  I plan to do further experiments with light painting for real estate type shots.

Getting More Experience (Intermediate)

One of the best ways to improve photographic skills is to acquire more 'real world' experience. In that regard, don't limit yourself to weekends, vacations or family events. While it's unlikely that a professional wedding photographer will want to work with you if you have little or no experience, there may be excellent learning opportunities in your community, organizations, or at work, such as company parties.
Volunteering to take photos at such events is a low pressure way of acquiring valuable experience. For even less pressure, volunteer to take photos at less formal events first and work your way up from there. In any case, most of the time, people have very reasonable (i.e., low) expectations and will be appreciative of your efforts.
You'll learn more if you treat it as you would a professional photographic engagement. Suggestions:
1. Research the area where the pictures will be taken to visualize shots you would like to take.
2. Based on the location, think of your lighting strategy (Use just ambient light? Is bouncing possible? etc.)
3. Make sure your equipment is ready (main and backup batteries charged, memory cards cleared, etc.).
4. Find out the schedule (if any) from the organizer so you can anticipate when you need to take shots (and when you can take a break and eat).
5. Find out if there are any VIPs. Not necessarily prominent people - these could be guests who are important to the celebrant.
6. Respect people's preferences -- some people don't want to be photographed, period. Conversely, some people like being photographed (generally, more attractive people do).
After the event, while doing the postprocessing (you will won't you...? :) ), identify some of the things you did right, and some areas where you would like to improve. With respect to the latter, do some research on how to do better next time.