Artificial Light Sources

What's the best light source for photos??? For a long time I was hooked on high efficiency fluorescent lamps that last 10x longer than incandescents, run cool and use less energy. I thought I found some that were "white", but after trying to photograph stuff under them, I could never get the colors to look right. I was searching for a nice white light source that could be used for photography -- Of course there's lots of really expensive lamps out there, but I'm a poor student and want something I can use every day. Then I found these GE Reveal lamps. They are whiter than any other source I've used so far. They are ordinary incandescent lamps with a bluish neodymium glass that cancels out the red-heavy spectrum from ordinary incandescents and adds some blue for a nice balanced white output! At first, I bought the 65W floodlamps, but found them to be pinkish - they make reds come out too oversatured and skin tones look slightly reddish. Then I bought the normal style (Type A) bulbs in the 75W rating and they are fantastic! I used them in my dorm and office now because the light is so much nicer than the fluorescents. They're great for people photography! Ordinary incandescents look yellow, even color corrected fluorescents give a yellow-orange glow, the flash is too blue, and even halogen lamps modify skin tones unnaturally. But GE's Reveal bulbs are a really pleasing white!

It makes sense to use modified incandescent bulbs as light sources because they are blackbody radiation sources and have no peaks in their spectrum (just a red-heavy tilt). Fluorescents, but contrast, have several major peaks in their spectrum, especially green. No matter how hard you try, you'll never get colors like magenta and orange to come out right is there's a strong green peak. By far the worst lamps are those sodium street lamps - they have almost a pure orange component with nothing else - you often can't even tell the difference between brown and blue under them!

All tests were done using a Canon 1D with the Color Matrix-1 (default) setting in Manual mode +2/3 stop exposure. The Canon 24-70mm f/2.8L USM lens was set to about 50mm, f/4 with an exposure time of around 1/50 sec (varies slightly). The lamp was about 18 inches from the subject and may have moved slightly each time I switched the bulb (sorry! The flash could have been more carefully placed). No photoshop processing was done, except to change the image size and the color space of the photos was preserved.

Two tests are done below: one in the 1D's Automatic White Balance (AWB) mode (external sensor plus captured info) and once using the Custom White Balance (CWB) setting. For the CWB, a piece of white photographic paper was placed just infront of the subject was photographed (at lower exposure to prevent saturation) to provide a white standard for the camera to calibrate against. Unless you have the time and ability to photograph a white sheet first, it's preferable to just use some auto setting for convenience. Furthermore, if you're using film, you want the colors to be correct from the start without using filters!!

NOTE: If your monitor does not have the colors calibrated, these photos may look different from my comments. For example, my laptop monitor does not reproduce yellow very well, even though I calibrated it, so the fluorescent bulb doesn't look so bad. On my better office monitor (calibrated), however, it does look more yellow, and if you print it out, it will also look bad!

Test #1: Using Auto-White-Balance (AWB):

Reveal (A)(1)

Reveal (FL)(2)

Halogen(3)

Incandescent(4)

Flash Comp(5)

Flash Uncomp(6)

Cmpct. Fluro(7)

(Slide mouse over boxes above)

Results:
1. GE Reveal Type A Bulb: 75W -- Very smooth and balanced white color! They cost about $6 for four!
2. GE Reveal Floodlamp style: 65W -- Nice white, but makes the red bottle saturate too much.
3. Halogen bulb: 15v, 2A -- Slightly yellow overtone, desaturates blues, gives slightly unnatural skin tone cast
4. Regular incandescent: Yellow and orange stand out and the orange has a yellowish cast. Purple loses its purpleness.
5. Camera flash: Comp=compensated in camera using FLASH White Balance setting. Skin tones are dry, red is a little dark.
6. Camera flash: UnComp=uncompensated. Using camera Auto White Balance setting. Blues are strong, skin tones are cold and dry!
7. Compact fluorescent bulbs: Terrible yellowish-orange color (I can't describe it in words but to say you'll never get the colors to look right!)

Test #2: Using Custom-White-Balance (CWB):

Reveal (A)(1)

Reveal (FL)(2)

Halogen(3)

Incandescent(4)

Flash(5)

Cmpct Fluro(6)

(Slide mouse over boxes above)

Results: Using the CWB, the results are more similar, but there are still subtle differences.
1. GE Reveal bulbs: 75W round Type A -- Very smooth and balanced white color!
2. GE Reveal bulbs: 65W floodlamp -- Very similar to #1, but skin tones are more pinkish.
3. Halogen bulb: 15v, 2A -- Yellow cast, orange doesn't look orange like it does in #1.
4. Regular incandescent: Not bad for skin tones, but colors look slightly washed out using CWB compared to #1.
5. Camera flash: Colors are very good except for a desaturating purplish shift on the red bottle.
6. Compact fluorescent bulbs: Yellow is HOT!! All colors receive an ugly yellowish cast.

And the winner is.... Definetely GE's Reveal bulbs. The whiteness is immediately evident compared to regular incandescents. Although they won't last as long as the compact fluorescent nor save energy, they also cost less and give much nicer light! I've had a tough time photographing people indoors because my flash color looks terrible mixed with the normal indoor incandescents. Now I'll carry a Reveal bulb with me if I have to take people portraits.

UV/Haze Filters

Do different UV filters make a difference??? I bought an expensive $75 B+W MRC UV filter for my Canon EF 28-70mm f/2.8L USM lens because I heard it was the best UV filter available. When I took a picture into the sun, I saw no flare at all -- it is awesome. This lens is fabulous in and of itself, but I suspected the filter had something to do with it too, so I upgraded all my other UV filters to the B+W MRC and during the switch, I compared the cheap and expensive filters. Wow!! I'll never buy a cheap filter again!!!!

This photo was purposely constructed to give me some flare -- maybe you'll never take a picture like it and maybe it's kind of an unrealistic test. But it goes to show that there really is a difference in quality, and it can make or break your shot if you do take a photo like this. On most of my night photos I've had flare problems, so I can't wait to try them again with the new filters! I had the camera on manual mode with manual focus to make sure the shots came out with the same exposure. Pictures were taken with the Canon EF 50mm f/1.4 USM on a 300D.

No UV Filter

B+W MRC UV Filter

Digital Vision Cheap UV Filter

                 (Slide mouse over boxes above)                 

The 58mm B+W MRC UV 010M Filter has a slight fuzzy flare spot near the yellow car, but that's all; everything else is exactly the same (well, maybe a "slight" reduction in contrast).

By comparison, the cheaper Digital Vision UV Filter gives you a BAD flare shot and also puts an orange/ red cast over the whole picture; even in the shadows!! Yuck! It also reduces the contrast of your lens.

As you can see, the B+W MRC filter beats the socks off of the cheaper one. Of course, no filter at all is even better, but that's risky in case you accidentally scratch the coating on your lens (or worse yet, the lens itself).

Different Focal Lengths

This is a series of images I took using the 300D with a few lenses. I wanted to see the effect of different focal lengths on a fixed scene, so I moved my tripod back and forth to try to frame the same subject (but I didn't do a very good job!). With the 14mm lens, I was just a few inches from the front of the shelf; while with the 85mm lens, I was squeezed in the back of my room.
# NOTE: I was recently informed that the effect of depth in a scene is not due to the focal length but rather the distance from the subject. "8 feet feels most natural" according to the comment. The short focal length rather lets more of the scene in at the same distance than a long focal length would. So I guess, in theory, if you had a camera with a ton of pixels and you had a really good wide angle lens, you could take a picture of anything and crop it and not tell the difference from a telephoto. [12/05] #

Directions: Move your mouse pointer over the numbers in the table below to change the image in the box in sequence. Take particular note of the big difference between 85mm and 14mm: The 85mm makes the scene look very flat, while the 14mm gives it a great sense of depth. I was amazed to see the large difference between the widest focal lengths ; but also surprized to see that there is a noticeable difference even at long focal lengths.

14mm(1)

18mm(2)

24mm(3)

28mm(3)

35mm(3)

50mm(3)

70mm(3)

85mm(4)

<== More depth                                   (Slide mouse over boxes above)                                   Flatter ==>

Keep in mind: These were taken with an APS-C sized sensor with a 1.6x crop factor, so the effective lens lengths are 1.6x longer (14mm*1.6=22mm ; 85mm*1.6=136mm ; etc.)

Alignment of the subject becomes much more difficult and important at really wide angles. It's tough or impossible to keep all the straight edges straight.

⁽¹⁾: Sigma 14mm f/2.8 HSM ; ⁽²⁾ EF-S 18-55mm kit lens ; ⁽³⁾ EF 24-70mm f/2.8L USM ; ⁽⁴⁾ EF 85mm f/1.8 USM