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View Full Version : Woodturning Photo tips week 3



Brian Brown
05-13-2007, 8:37 PM
Lighting the subject

Subject lighting is a very involved subject, so I’ll take a few weeks to tackle it.

This week White Balance and simple lighting.

There are many different ways to accomplish a similar goal when photographing your woodwork. Flash, tungsten or halogen lights, or sunlight all work, but each has its own challenges. One of the biggest challenges you will face, is getting good color. All light has color and when you match the color of the light and the settings on your camera, the color in your pictures will look like the color on the real project. If you have a mis-match between lighting and camera settings, there will be a distinct color cast to your images.

There are at least 6 common light sources and colors that photographers face. Daylight, shade, overcast, flash, incandescent, and fluorescent. Daylight is simply light that is near the same color as direct sunlight, and can come from several different sources. Shade is lighting under a tree or in the shadow of a building, and overcast is light under a cloudy sky. Tungsten is light from household light bulbs or quartz halogen lights. Fluorescent is obviously lighting from fluorescent fixtures. Camera flashes are designed to be a close color match to daylight.

Most modern digital cameras have a setting to match the color of light source to the camera. This is called white balance (WB). To get the best possible color, it is critical to set the WB before you take the picture. Most cameras have an automatic WB setting. This works well much of the time, but just like getting the right exposure requires an average scene, auto WB also requires an average scene. If there is a dominate color in the scene, and/or no neutral white or grey area, the scene will fool the camera, and you will get an unwanted color shift. In these cases, you will have better success if you manually set the WB. Your manual will tell you exactly how to set the WB, but in general for most cameras:
For sunlit subjects, set the WB to sun, the sun icon, or a number near 5500K.
For tungsten lighting, set the WB to indoor, the light bulb icon, or a
number near 3400K.
For overcast lighting, set the WB to cloud, the cloud icon, or a number close to 7000K.
For images taken in shady areas, set the WB to shade, the building shadow icon
(sometimes a tree icon) or a number close to 7600K.
For flash, set the WB to flash, the lightning bolt icon, or a number close to 5700K.

Any of these light sources can produce quality images.

As for fluorescent, Just Say No! Fluorescent light is garbage. Even though most cameras have a WB for fluorescent, they struggle to get good color. There are a number of complex and messy technical issues that cause this, so for your own sanity, don’t use fluorescent light. If you are already using the high CRI lights and like the results you’re getting, then keep using them. If you have not got a fluorescent set-up, don’t. Use one of the other types listed above.

Now, lets broach that dreaded topic SHADOWS. As I read the forum questions about getting better pictures with no shadows, I just cringe. Shadow are our friends, not our enemies. Try to think of shadows like dogs. Nobody likes an untrained, out of control dog who chews on stuff, chases people, and does whatever it wants to. However, a well trained, under control dog is mans best friend. So like the dog, we are going to train and control our shadows, making them an important part of our pictures. We are trying to depict a 3 dimensional object on a 2 dimensional piece of paper, so we use shadows to give the illusion of 3D. It is possible to create a picture that is almost shadow less, but by doing so, we will be removing any shape and texture in our subject. We refer to these images as “Flat”, because this type of lighting flattens out the features of the subject. You worked so hard to roll that perfect bead, or carve that fine detail, so lets make it show up in the pictures. We do that by careful placement of shadows. It’s not hard , but does take some practice.

So to start, don’t use a flash mounted on the camera, or else turn it off. If the flash is built in, there should be a menu setting to turn it off. Any light that comes directly from the camera will flatten your image and cause hard ugly shadows behind your subject. It also causes a bright reflection in your piece, usually at the top center. The more glossy the piece, the worse the reflection. Now that your flash is off, we need a light source, so let’s start with the cheapest and easiest… Window light. We want a window with bright light coming in, but not direct sunlight. Set your project up a few feet from the window like in picture A. The light should be coming from the side. Remember the light source is not direct sunlight, so cloudy or shade is your best choice for WB. Avoid strongly colored walls or other objects as they can reflect unwanted color into the image. This setup alone may provide you with an excellent image, but if the side shadow is too dark, let’s control it. Just take a piece of white paper and place it along the shadow side of your subject, (picture B & C) to reflect light into the shadows. Closer to the subject makes the shadows lighter. Move it back and forth until you have pleasing shadows, and shoot the picture. I used card stock from Staples...13 cents. For less than $1.00 you can get excellent results.

In next weeks tip, I’ll cover some inexpensive light fixtures and ways to control each of these light types, and the shadows associated with them.

Brian Brown
05-13-2007, 8:43 PM
Here are some pictures illustrating the difference in WB selections. The lighting was the same window light described in the previous post. The camera should have been set to cloudy.

Jamie Donaldson
05-13-2007, 8:58 PM
... he selected a blue background- not a good color for wood when the light bounced from the blue surface tints the wood and shadow areas blue. We are interested in a literal rendering of the wood, and the neutral background colors of white, light gray, or black (for light colored wood like maple) work best for accurate color reproduction.

Paul Andrews
05-14-2007, 6:43 AM
Brian,

Thanks for the continuing photo tips. As for the color of the background, each individual can make that decision for themselves!

Greg Savage
05-14-2007, 8:07 AM
Use a light grey or medium grey seamless backround. Art fair jury slides and any profesionally photographed art or craft work employ a neutral backround. Different techniques can be used to achieve the necessary gradation for depth, thus the backround may blend from light gray to a nearly textureless black.

Jay Drew
05-14-2007, 8:42 AM
When you say stay away from fluorescent does that include the 5500k daylight compact fluorescent bulbs? I was planning to use these on my photo setup but I didn't start building it yet so now is a good time to change my plans.

Mark Pruitt
05-14-2007, 9:22 AM
Great tips Brian. Keep 'em coming!

Jim Becker
05-14-2007, 9:22 AM
As for the color of the background, each individual can make that decision for themselves!

That's true, but Jamie has a LOT of experience with photography around turnings (he's also a pro photographer and has conducted seminars at AAW symposiums on the same) and it is indeed true that colored backgrounds tend to telegraph onto the workpiece, especially on light to mid-toned pieces. It's a matter of how light bounces and the effect that has on the workpiece in question, not necessarily personal preference on a color you like. His advise over the past few years has helped me a lot in my own photography.

Tom Sherman
05-14-2007, 4:15 PM
Jamie your tips are making sense to me keep em comin.

Brian Brown
05-14-2007, 7:40 PM
Jay,

When I say avoid fluorescent, I mean all of them. It is not that fluorescent is so terrible that you won't get an image, but that there are better quality sources of light available. Fluorescent is not a full spectrum light, and even those that are close are lacking the richness of the spectrum. Remember when you were in high school science class, and you held a diffraction grating up to the light and it broke the light into the rainbow spectrum? If you did the same to fluorescent lights, there would be gaps in the spectrum (missing colors). Photographs depend on the light reflected from a subject. If the color of light wasn't there in the first place, it cannot be reflected to the camera, so the pictures may be missing colors in certain areas of the spectrum. This caused some colors to reproduce poorly or not at all, and subtle color differences hay disappear completely. The 5500K tubes are better that the cheap ones you get on sale, but they are still missing some of the colors of the spectrum. These 5500K lights are sometimes referred to as having a high CRI (color rendering index). The long and short of it; high quality fluorescents can work, but there are much better sources. If you live in Tucson AZ, or some other place equally hot, you may appreciate the cool running temperature of fluorescent lights though. Hope this helps.

Brian

Jamie Donaldson
05-14-2007, 8:50 PM
...fluorescent lights for photos- a $9.95 Q/H work light(500w) at Lowes will give a good color balance match to the tungsten/incandescent settings on most digital cameras.

Bruce Shiverdecker
05-14-2007, 10:39 PM
Evening. Brian. I noticed that you used a Blue background. I have purchased a light box that has a blue background.

However, when I show a picture with a blue background, I get dinged. I didn't think blue was bad, but others say it's a NONO. What are your thoughts. The picture was taken of a light object. I posted it here. I know that there are some other problems, but I want your opinion on the blue.

Here is the post "Photographing Turnings"

Thanks,
Bruce:o

Brian Brown
05-15-2007, 12:45 AM
Jamie,

I wondered how long it would be til someone took me to task for the blue background. This tip was mostly about white balance. The reason I used the blue background was to show how a dominate color could fool the auto white balance. I had another picture to illustrate this, but the wind was blowing so hard on my wireless antenae that I couldn't keep a good web conection. After an hour I gave up. In the pictures that show the different white balances, I made an effort to make the background and subject take about the same amount of space in the image. The auto white balance was still fooled. The missing picture shows more background, and the auto white balance did even worse. Normally for a juried show, I wouldn't use a colored background, unless a client specifically demands it (yes it has happened several times). I should have taken the time to take an image on a neutral background for the lighting setup. When I started this series, I said that the main purpose for the tips was to help with submissions to juried shows. I also wanted to give help with images for web sites, and printed materials. I find that a colored background can be an asset as long as the color can be kept from reflecting and significantly tainting your wood color. I'll cover this when I talk about backgrounds. When It comes to juried shows, unless there is a very good reason for a colored background, a neutral background is always better. Sorry for any confusion.

Brian

Brian Brown
05-15-2007, 12:50 AM
Bruce,

To answer your question, see the reply I sent to Jamie.

Brian

Bruce Shiverdecker
05-15-2007, 1:18 PM
Thanks, but, if "Royal" blue is bad, Why would they include it as one of the backdrops in a light kit? The other side is a medium grey.

Not trying to be a Smartallic here. Just trying to figure it all out.

Bruce

Brian Brown
05-15-2007, 1:40 PM
Bruce,

The royal blue is a "generic" background. Remember that the tent/box outfit you bought is intended for a wide audience, not just woodworkers and artists. My own personal opinion, it is included, because it draws the eye when you are looking at the sales info for the company. Just marketing. That's why when I get to backgrounds, I'll talk about other colors besides neutral.

Brian.

Bruce Shiverdecker
05-15-2007, 10:55 PM
Thanks, Brian.

Bruce