Janice and Jeff's Wedding

Pam and I had the pleasure of shooting at Janice and Jeff's wedding. It was a very lovely wedding and we had a blast both as guests as well as photographers. Speaking of photographers, I've never seen so many photographers AND videographers at a wedding in my entire life! I can only imagine that the coverage was superb. Anyways, without elaborating further, please enjoy these pictures that Pam and I took! By the way some of the pictures below are CLICKABLE as easter eggs to bigger resolution pictures. Have fun!



That's it for now.! If you need photographers or need recommendations on photographers (I know a lot of them) you can email me. My contact is posted on www.KameraKevin.com. -Kevin and Pam

Catch light in models

I was curious one day and went to the women's hair coloring section in Walgreens and snapped a few pictures with my wife's Canon SD750 (it is such an amazing camera!):

No, I didn't walk in with an SLR. I find that the moment I put my eyes through a camera's view-finder, I get kicked out 90% of the time whenever I'm on a private property for one reason or another. SLRs are huge, cumbersome, and impractical to use most of the time.

I organized the snapshots below. Take a careful look at them. Photographically speaking, what do these pictures have in common? Which pictures do you like/dislike and/or catch your eyes? Try to answer these questions as you're looking through these pictures:

Photographically speaking, these pictures have the followings in common:

1) All of them used diffusers (bounce, softbox, octobox, or umbrella) to cast gentle lighting on the face, to either carve and accentuate some parts of the face, or to flatten the shape of some parts the face.

2) All the eyes are in sharp focus. They say the eye is the window to a person's soul, and when the eyes are in focus, the entire picture is in focus [psychologically speaking].

3) Almost all have at least 1 main catch light in the eyes, placed between 1 o'clock and 11 o'clock position-- aka your very standard text book studio shot. Wikipedia says "Catchlight is a photography term used to describe either the specular highlight in a subject's eye from a light source, or the light source itself. They are also referred to as eye lights or Obies, the latter a reference to Merle Oberon, who was frequently lit using this technique. A catch light may be an artifact of the lighting method, or have been purposely engineered to add a glint or "spark" to a subject's eye during photography. This technique is useful in both still and motion picture photography. Adding a catch light can help draw attention to the subject's eyes, which may otherwise get lost among other elements in the scene."

4) All the catch light are using interior artificial lighting, be it an umbrella, softbox, octobox, or some type of studio diffuser. Four models on the left column used a single softbox (square). A softbox looks like the following:

In fact, if you look at the eyes carefully where there is a white bright square in their eyes, you'll also see a little bit of a ball shaped thing below the white square. That is actually a photographer's head! This is pretty common in studio settings where you want the softbox slightly on top of the model, and the photographer needs to get in front of the softbox to make the shot.

The rest of the pictures use either octobox or umbrellas. An octobox looks like the followings:

Portable studio umbrellas look like the following (there's also a bounce panel to the right):

When a human being looks at a portrait, he/she has an intuition what looks good or not. But photographers can go one step further and decompose and analyze at how the portrait is shot. In the case of portraits, pictures that have catch light have a higher tendency to catches the viewers' attention.

There is one picture that does not place the main catch light between the 1 o'clock and 11 o'clock position. That's the bottom right model where the catch light is actually below and to the right of the model's pupil. This gives her a little bit of a mysterious look (along with a darker broad lighting position to cast more shadows on her left cheek, to make her look even more mysterious than the other models).

Going back to the model pictures, which models catch your eyes? What lighting techniques are used in those pictures that you like? Do you prefer a single source catch light, or multiple light source catch light? Do you prefer the look of a softbox (looks more like a window), or do you prefect the octobox/umbrella look?

* Men's hair dye products do not emphasize the eye as much. The catch light is typically smaller because the photographer usually moves the lighting a bit farther. Farther lighting source gives a bit more harsh feel to the face (opposite of diffusing light for women), which is appropriate if you want the man to look harsher and more manly. Go to any men's hair color section and you'll see what I mean-- smaller catch light, harsher lighting source that yields more square looking face.

Filters and flare

They say that it's best to put on a filter on your lens to protect it. It's cheaper and more effective than having camera insurance. There have been hundreds of stories on the internet where multi-thousand dollar lenses were saved from crash/drop by putting cheap UV filters (and/or hoods). However, filters come with a price-- decreased image quality. Adding an additional glass means the lens will get flare more easily. This is especially true when shooting directly into a light source where the light source becomes a flare at the opposite side of the frame. Below is an example of a green flare, thanks to a cheap UV filter, when shooting into the moon:

Adding a filter also means decreased of light going to the camera. A cheap lens today in general will allow 90% of light source going through, and a really high end one will allow 99% going through. However, this is actually quite negligible. 10% is miniscule compared to how much aperture I can open up or how high ISO I can crank up in today's modern DSLRs. Each stop means 50% or 200% difference, so the decreased of 1% to 10% of light is a non-issue, at least for me.

Going back to the issue of image quality -- this is a real concern. Below is a wonderful HDR picture that Ping shot in Alaska with a B+W UV MRC filter. Notice the green flare to the left-bottom corner of the pictures. Personally I think it is fine as it adds some artistry to it... in fact often times people add in fake flare in Photoshop to spice up their pictures.

On the other hand, real flare can come at inopportune moments when you least want them to exist. In my past I never really cared about flare until one day, I came back from from a wedding shoot, and was horrified at a bunch of green flares on people's faces. They're shot using my amazing Sigma 50mm f/1.4 but sadly mis-paired with a really really cheap 77mm Hoya 81A filter! "Why on earth would you use a 81A filter at night" you may ask? Because I didn't have any other 77mm filter at the time, and shooting without a filter while I run around doing event photography is utterly out of the question for me.

The first example below is acceptable because the flare is not interfering with the subject. It just so happened that none of the green flare got on Jennifer, yay!


However, subsequent examples are where I really didn't want any flare to occur, but I did not realize that it was happening at the time since I was too busy shooting and I didn't have time to chimp the LCD. Moral of the story: chimping IS GOOD FOR YOU! Sometimes.
All of this of course could have been mitigated by 1) using a flash and blow away all warm natural lighting [thus rendering the color out of whack and will need to turn night pictures into black and white] 2) using a higher quality filter 3) not using a filter 4) not shooting into the light source (candles). On the other hand, I really wanted to capture the candlelight to emphasize that all these shots were made possible with nothing but natural candle-light. Most photographers will just opt for 1) because flash is a lot easier. Capturing natural candlelit subjects usually requires 1600-3200 ISO, 1/30 sec, f/1.4-2.0 (below EV2)... or pretty much at the limits of what steady photographers can hand-held AND pushing the technological limits of today's DSLRs sensors.

In short, not all filters are equal. I have compiled a list of the filters that I've been using below and some examples shots. The first row shows examples of NO FILTER. Subsequent rows show the 77mm Hoya HMC 81A, 77mm B+W 010 UV Haze MRC x1, 77mm Hoya Super HMC UV(0), 72mm Hoya HMC UV(N) and just for kicks a 77mm Hoya NDX8. The second column shows the reflection of the filter and a full-spectrum CFL light source (rated at 94 CRI) where you can look at the colors of the filters. The last 2 columns show an example of shooting into the light source, and the flare on the opposite site of the frame. Are of them were shot using a Nikkor 85mm f/1.4D (portrait lens) on a tripod:

In short, I had a very high expectation of the German made 77mm B+W 010 UV Haze MRC x1 and I was very disappointed with it. People on the internet seem to say that it is great... that it is what German engineering is about. However, my tests show that it simply blows. In fact it is *MORE* expensive than the Japanese made Hoya Super HMC, and performs as badly as the cheap Hoya [regular] HMC. Personally, I've never been impressed with the value/cost ratio of BMW cars vs. Lexus, and this test just made me feel the same about B+W vs. Hoya.

One last note. I didn't cover color range and IR/UV accuracy. I've seen tests that show that the Hoya Super HMC blocks way more IR and UV that it is suppose to thus creating color shifts, and that the B+W MRC has a much more accurate IR/UV block off points. However, without instrumentations I can't validate those tests. If color is a more important issue than flare, perhaps the B+W MRC is a better choice. Trade-offs.

P.S. For more formal results you can visit an external link here:

http://lenstip.com/113.4-article-UV_filters_test_Description_of_the_results_and_summary.html

Modular Transfer Function (MTF)

Courtesy of Norman Korman (http://www.normankoren.com/Tutorials/MTF.html)

I was going to post this long time ago but today I'm motivated to finish it because a friend asked me "I have a 15MP Canon T1i camera, should I buy a Canon 18-200mm f/3.5-5.6 IS to replace my 18-55mm version?" Well, it depends. If the lens will give flexibility when shooting kids from wide to zoom, AND it's only going to be used on the internet (1600 pixel width), AND you don't care about optical quality, then by all means get the 18-200mm lens. On the other hand, the results may be disappointing when zoomed in to 1:1 resolution or printed at 8x10 or 11x14 and above because super zoom lenses like the 18-200mm get convenience and trade-off with inferior optical quality. So if one must use the 18-200mm lens, one might as well as shoot it on a 8-10MP camera because at full 15MP, pictures will have a tendency to look "soft" and "mushy"... they will look not much better than shooting with a lower megapixel sensor and then upsize it later in Photoshop.

Let me just say that when I need convenience, I'll simply use my wife's Canon SD750 point-and-shoot, which is a superb camera to shoot casual events... kids, pets, what not. I don't usually care about optical quality for casual events. In fact I don't expect the quality of the SD750 to remotely match that of modern DSLRs+pro-lenses. On the other hand if I'm serious about something, I'll get SLR equipments but not just any SLR equipments-- pro-lenses. There's no point of buying a toy consumer 18-200mm lens when a point-and-shoot will shoot just as well. Having that said, two years ago I bought the Canon equivalent-- back then a spanking brand new Nikkor 18-200mm f/3.5-5.6 VR. I had it for about 2 months. I sold it (on eBay) after only using it for 2 months because I was very disappointed with its optical quality. In fact, eBay today is full of used 18-200mm lenses-- people are now starting to discover that super zooms don't project good quality images, and are dumping them back to the used market.

So let's assume now that optical quality is in fact of high concern, how should one determine in general whether a lens is well matched for a particular MP sensor? You compare technical specs. However unlike looking at a single MP value, lenses are a bit more complicate. Lenses are usually characterized using the Modular Transfer Function (MTF).

Originally MTF started from USAF in the 50s when the air force wanted to know how much "lines PAIRS per millimeter" (lp/mm) a lens can resolve (this is different than l/mm!). The higher details, the more information they can get from the Soviet Union using high altitude spy planes and spy cameras. In the old film days, lp/mm was used commonly because there were only a few common formats: 35mm, medium format (45, 67, etc) and it made sense to talk about lines per millimeter projected on film. Today with a plethora of digital sensor sizes, people use lw/ph or lwph (line width per picture height) in favor of the older lpmm unit. Keep in mind, the two aren't equivalent and requires calculations to get from one to another, but for the sake of simplicity, let's just agree that the higher MTF value, the more details a lens can resolve. By the way there are a bunch of good technical MTF information online. My favorite is the following URL. Is this really necessary to read? Yes, absolutely, especially if you're a pixel peeping/engineering/math type of person:

http://www.luminous-landscape.com/tutorials/understanding-series/understanding-mtf.shtml

So going back to the question "I have a 15MP camera, should I get a 18-200mm f/3.5-5.6 IS lens to replace my 18-55mm vesion?" Unlike the camera body, we can't simply look at one single MTF value on a lens. What makes lens comparison complicated is that the center resolution will be different than the corner resolution because unlike a uniform sensor/film density, the projected optic quality isn't uniform throughout the area. To make things more complicated, lens resolution varies with aperture as well; subject to the laws of optics engineering and design, the higher the aperture, the higher resolution, and likewise the wider-open the aperture, the lower resolution. So we have two basic things to worry about now: 1) how much resolution in the different areas a lens projects 2) how much resolution using different apertures. In fact to make things even more complicated there are a bunch of other factors to consider (but we won't get into it here): contrast vs. resolution, color, chromatic aberration, vignette, distortion, and bokeh (BTW I hope I've made pixel peepers happy by mentioning all of these other issues).

Unfortunately, most manufacturers have their own MTF values derived from theoretical/calculated results. In fact, they don't make it easy for consumers to access that information. In addition, manufacturers' MTF is a lot lower than the theoretical values due to manufacturing variations, and subject to real world conditions (heat, humidity, calibration, irreproducible lighting levels, etc). Luckily however, there are numerous MTF charts published by independent testers online. Photozone is one very good European company that publishes optical results. Let's look at the MTF for the following two lenses:

18-55mm 55-250mm	18-200mm

Go to both pages, scroll to MTF for 18mm at f/3.5. You'll see that for center MTF value (middle of projection), both lenses resolve almost the same lp/ph. Now, look at border MTF value (edge of projection), and you see while the 18-55mm resolves at 2182 lw/ph, the 18-200mm resolves at an abysmal 1703 lw/ph. Extreme corner is another story to be told. Based on this MTF, one can say that the 18-200mm lens often yields mushy looking images. "This lens at f/3.5 and 18mm isn't very sharp" is what photographers would say. You can look at other apertures and other zoom ranges and see that aperture-for-aperture, zoom-for-zoom, the cheaper 18-55mm lens usually out-performs the much more expensive 18-200mm lens! (see footnote 1)

In short, lens engineering is about trade-offs, and one of the big trade-offs is convenience vs. optical quality. I understand that the 18-200mm lens is much more convenient for shooting pets and kids. It's certainly more convenient than having to switch between 18-55mm and 55-250mm lenses. So if convenience is the primary issue at hand, the 18-200mm is a fine lens. Just don't expect crystal sharp pictures.

If on the other hand optical quality is of importance (portrait, event, wedding, poster, etc), then don't get the 18-200mm. Instead get a better lens that can also resolve just as much resolution as the sensor has. MTF is your friend.

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Footnotes:

1) One can make the argument that you can just close up the aperture to f/5.6 and beyond and both lenses will perform superbly. As good as that sounds, f/5.6 is 1.5 stop lower than f/3.5. That means the lens opening at f/5.6 is roughly 1/3 (1/(2^1.5)) than at f/3.5. Shooting f/5.6 under anything but bright day will yield a lot of disappointments.

Lynn & Ross' Wedding

Lynn and Ross are x-coworkers/friends from the Google days. They got married on August 22, 2009 in Malibu, Adamson House. What more could you ask for when you mix a beautiful day, a beautiful couple, and a beautiful location! Click www.lynnandross.com for more info.

I wanted to make sure this special couple had a good coverage throughout this once in a lifetime event and came in as a secondary/third shooter. Since we were not primary shooters, you will not see a single portrait of Lynn and Ross and no close-up of rings, shoes, etc on this web site. Enjoy!

I hope you enjoyed these pictures that Pam and I took. For other photographer's pictures, you can check out Michael+Anna's web site. They're very good, you have my endorsement!