Saturday, November 28, 2009

The 50mm Lens

At the beginning of the year, I bought my wife our 50mm f/1.8 lens for her birthday, and we've loved it! The photos of our son Logan in this post were taken by her with the 50mm lens.

50mm, 1/100 sec at f/1.8, ISO 200

If you're lucky enough to own an SLR camera, then I think you should also consider getting a fixed-length 50mm lens... and here's why.

First, a little background. 50mm is a special focal length in photography; a 50mm lens is also referred to as a "normal" lens. The reason for this is that, on a 35mm film camera, the perspective you get with a 50mm lens is the same as human vision. You can look through the viewfinder with one eye, and keep the other eye open, and you should be able to see normally.

So why did I mention a 35mm film camera? Well, 50mm isn't actually "normal" on our camera (a Canon 20D) or probably yours. The reason for this is that the sensor in most digital SLRs is not as large as 35mm film. Instead, our digital cameras use a sensor format called APS-C which is less than half the size of 35mm film.

The smaller sensor size has a magnification effect that's referred to as a "crop factor". APS-C has a crop factor of 1.6, meaning that a 50mm lens on our camera has the same field of view as a longer 80mm lens on film. To truly get a "normal" perspective on our camera, we'd need a lens with a focal length of about 31mm. Nonetheless, the 50mm lens has remained a very popular length for photographers.

50mm, 1/1250sec at f/3.2, ISO 200

Aside: Why are the sensors smaller in digital cameras?
Well, professional-level digital SLRs, such as the Canon 5D, do actually have "full frame" (35mm) sensors... and they cost more than twice as much as the next camera down. The reason for this is pretty simple--the cost of manufacturing semiconductor chips is pretty directly related to their size. You can only fit so many chips on a wafer, and larger chips means fewer chips per wafer. Creating cameras that use a smaller-sized sensor makes them affordable enough that you and I can have one.

One of the biggest advantages to a full-frame sensor is that it can have the same number of megapixels as a smaller sensor, but without having to pack them in as tightly. This makes a big difference in the noise performance of the sensor. A shot from a Canon 5D at ISO 1600 will look a lot cleaner than it does on our 20D at the same ISO. Another difference, which relates to the crop factor, is that full-frame sensors have a shallower depth-of-field for a given aperture, making it easier to achieve artistic blurred backgrounds.

Ok, so now we know why 50mm is a (historically?) significant focal length, but why would you want a fixed-length lens? Don't you want the flexibility to zoom in and out? Isn't being stuck at one focal length a huge pain?

There are actually a number of advantages to using a fixed-length lens (also called a "prime" lens) over a zoom.

A fixed-length lens is much simpler to design and construct than a zoom, and this has two important consequences. The first is that they can have much better performance than zooms. The simpler design and less lens elements means that they produce some of the sharpest images, and can have larger apertures (for low light and shallow depth-of-field) than any zoom. The second is that they can be made cheaper--much cheaper. To put it in perspective, my wife enjoys photographing people (especially our son), and would love to own the Canon 24-70mm f/2.8 lens.

Canon 24-70mm f/2.8

That lens alone costs about $1,300. Guess how much our 50mm f/1.8 lens cost us? $90! And note the difference there in maximum aperture--the $90 50mm can let it in more light (1 1/3 stops) than the $1,300 24-70mm zoom! I'd also point out that our 50mm only weighs 4.6oz, while the 24-70mm weighs 2.7lbs. That's half-a-pound more than our camera body, and literally almost ten times as heavy as the 50mm lens. That zoom lens is a beast!

Canon 50mm f/1.8

The fixed-length of the lens may seem limiting, but it can actually have some benefits to your work. It forces you to work within a single perspective, and to move yourself around and see things from different angles in order to frame your shot. The limitation can actually help inspire creativity!

50mm, 5.0 sec at f/22, ISO 100

All-in-all, the 50mm f/1.8 lens is one of the greatest bargains in all of photography. You get an incredibly powerful creative tool at a very low price (that is, relative to the crazy expensive world of photography).

I should point out that Canon actually makes 3 different 50mm lens. Amazon currently sells the f/1.8 model for $98, the f/1.4 for $375, and the f/1.2 for a cool $1,500. One thing that you'll notice about the f/1.8 (and probably an important factor in its cost) is that the housing is made of plastic. It's noticeable and not very sexy, but the savings are worth it.


If you decide to buy a 50mm lens, you can use any of the Amazon links in this post to buy it and I'll get a little commission for it. Or you can go straight to Amazon just to spite me :). Either way, go buy one and let it inspire you!!!

Friday, November 6, 2009

Beginning Editing (A Review of Google's Picasa)

I think a lot of people are afraid of editing their photos. It's so complicated and involved--there's way too much to learn!

I wanted to step back and take a very elementary look at editing, and try to convince you that the basics of editing are not hard at all, and definitely worth your time.

To do this, I want to show you how to use Google's free and amazing image organization and editing tool, Picasa. There's no fancy software or equipment required here, just a point-and-shoot digital camera and a free tool you can find on the web. You can download Picasa for the PC here or the Mac, here.

Managing Your Photos
Talking about managing photos has always seemed boring to me, but trust me, you'll appreciate what Picasa can do here.

Picasa is a superb tool for organizing your collection of photos. Some highlights are that it allows you to create 'virtual albums' which allow you to create a collection of photos without having them all live in the same directory on your computer. Also, it automatically creates backups of the originals of your photos so that you don't have to invent your own file naming scheme for maintaining original vs. edited copies of your files.

I want focus mainly on editing here, so to get you hyped about Picasa's many other cool features, I'll just point you to a video Google has created to show off Picasa, here.

On to Editing
When Jess and I first started managing our digital photos from trips we had taken and outings with our friends, probably 6 years ago now, we used a Windows tool called Microsoft Office Picture Manager. It had an 'auto-correct' button, and we'd go through all of our photos and auto-correct them. Usually the result was great, but if it was horrible we'd just undo it and move on.

Picasa has the same feature, but with a bit of a Google spin to it, as it's labeled the "I'm feeling lucky" button.

If you're someone who likes to take and share pictures (and of course you are), but doesn't want to learn a lot about editing, just hit this button. You'll be blown away by the results on many of your photos.

Here are a few before-and-after images that have been auto-corrected by Picasa. I honestly only had to hit one button. These are snapshots we took on a trip to Italy in 2005 with a 4 megapixel Olympus point-and-shoot, so nothing fancy here!



Eventually you will come across some photos where the auto-correct seems to do more harm then good. I think the "I'm feeling lucky" button is often just the same as hitting both the "Auto Color" and "Auto Contrast" buttons that are right next to it. Typically if you feel like Picasa didn't auto-correct the image well it's because it didn't get the auto color right. Try just hitting Auto Contrast and leaving it at that.

Plunging Deeper
Ready for a little more control, eh? There's a few other simple corrections you can make.

1. Fill Light
On the basic tab, notice the "Fill Light" slider towards the bottom. This is a handy, seemingly magical tool that fixes a common problem with photos. When we take snapshots, we rarely put much effort into getting perfect, even lighting on the scene. Your eye adjusts to different lighting conditions easily, so you don't really notice when, because of the direction or source of light, your subject is actually much darker than everything around it. The result is that your subject looks too dark in the final photo. Fortunately, the fill light tool can help. Push the slider towards the right and you will see your subject lighten up, as if someone had placed a "fill light" on the ground in front of you to brighten your subject.

This picture was taken in front of the Trevi Fountain in Rome. The fountain's in full sun, but we're sitting in the shade. I auto-corrected the image then added some fill light so you could still make out our faces. Man, we look young there!



2. Saturation
Go to the Effects page and click 'Saturation'. Most photos can benefit from a bit of a saturation boost, which will give the photo's colors some more punch.

Show some restraint, though! It's easy to get carried away with saturation and end up with some electric colors that don't look natural. Watch the areas of your photo that already have bright colors. If boosting the saturation causes you to lose a lot of detail in those areas, you're going too far.

3. Contrast
Picasa doesn't include a contrast slider, but if you look at the 'Tuning' page you'll see a 'Shadows' slider which allows you to darken the shadows and a 'Highlights' slider that allows you to brighten the highlights.Giving each of these a bump can add some extra contrast to your photo.


A little bump to the shadows and highlights can add some nice contrast

Experiment on your own
Picasa has a lot of other neat features, but I don't want to overwhelm you. Just play with what you've seen here, and eventually you'll be comfortable enough to start exploring.

For those of you who are already fairly comfortable doing some basic editing, I wanted to point out a couple other tools in Picasa that I think are really neat. One is the 'Retouch' tool, which allows you to easily remove dust marks and blemishes. The other is the 'Sharpening' effect, which applies some sharpening to your photos and can really help your photos look more crisp. Both of these features are things you usually only get in more powerful editors that you have to pay for, so it's really cool that Picasa includes them. I should say, too, that Picasa implements them very well and they're very simple to use.

Picasa's tools for helping you organize and play with your photos are a good enough reason to use it alone, but it also makes editing your photos so easy that there's really no excuse for not doing it. So go download it and have some fun!

Tuesday, November 3, 2009


This past Sunday was my birthday, hooray! My generous parents bought me a copy of Photomatix as a birthday present.

In a previous post, I explained the basics of HDR and played with a trial version of Photomatix which put watermarks all over the final images. Now I've got the real thing, though, and I'm ready to rock!

It's almost silly how much magic this software works.

I took this photo a couple months back in an effort to get back into photography. Even though the sky was amazing, I had a really tough time framing the fountain, the mission, and the sky. I came home that night really discouraged, but I'm glad I at least captured what I did!

Thinking back on it, what I really needed to do was to get further back so that the fountain would become a smaller part of the composition. The problem was, that fountain is right next to the street and there was a huge truck parked right behind me, so that was as far back as I was going to get. Maybe next time I'll reserve the space by parking in it :).

Thanks again, Mom and Dad, for the cool software!

Monday, November 2, 2009

Time-lapse Sunset

I think I've mentioned before that the back of our house has a great view of the sunset. The house sits on a bit of a hill, so the back end is raised pretty high off the ground, and we have a relatively clear view out to the west. Whenever I see a great sunset in the making out our back door (and they seem to happen pretty often around here), I tend to bemoan the fact that I can't be out somewhere interesting shooting it.

I've found a bit of a solution to that, though. The view isn't quite spectacular enough to make a single photo workable, but I think making a time lapse video can add just enough interest to it to make it fun.

Time-lapse Sunset, October 24, 2009 from Chris McCormick on Vimeo.

Technically, this isn't the first time I've done this. I shot another one of these over a year ago, but never really finished pulling the video together. I've learned a lot from these two attempts, and I think there are some good things that I can do to improve it for next time around.

Here's what I did to create this.

Taking the pictures
The video is composed of 159 shots each taken 10 seconds apart.

To take the shots, I setup the camera on the tripod, and hooked it up to our laptop.

Our Canon 20D came with some software called "EOS Capture" for basically controlling the camera from the laptop (for my own reference, you launch the "EOS Viewer Utility", then find EOS capture in the menu). One of the features is a sort of "intervalometer" which allows you to program it to take a certain number of shots with a certain spacing. I set it up to to take 180 shots at 10 second intervals, giving me 30 minutes. The camera battery wasn't fully charged, though, and it stopped shooting after 159. It's a bummer--you can tell from the video that there was still plenty of color left in the sky when it stopped!

As for the camera settings, I left it on aperture priority mode with an fstop of f/5.6. The lighting obviously changes as the sun goes down, so you need to use one of the camera's auto-exposure modes so that it adjusts. I chose aperture priority because I wanted to make sure that the depth of field stayed constant the whole time.

One thing I forgot about, though, was the white balance. I left it on auto white balance, which probably accounts for some of the shifts in color between different frames. Ideally, I think you'd want to have the same white balance the whole time.

I almost always shoot in RAW format, and with RAW you can go back and set the white balance after the fact. This time, though, I shot JPEG thinking that would save me a step, since the video software would likely need JPEGs. Oops!

Next time, I think I'll leave it on auto white balance, but shoot in RAW, and then go back afterward to apply the same color temperature to all of the shots.

Editing the shots
Yet another opportunity for me to rave about the merits of Adobe's Lightroom. It makes batch editing incredibly easy. You just select one of the photos, perform all of the edits you want to make--color, cropping, and all of that--then just copy those changes to all of the other photos. You select the photo you edited, click "Copy settings...", choose which types of edits you want to copy, select all of the other photos, and click "Paste settings". And that's it, it batch edits all of your photos for you. Sweet!

Knowing that this wasn't going to be much of a masterpiece, I edited the photos pretty hastily. I boosted the contrast and saturation, played with curves a bit to add more contrast to the sky, and cropped it into a 16:9 aspect ratio for HD video.

Creating the video
I was able to pull together the video in iMovie. I haven't used iMovie before, so it took me a while to figure out how to set the spacing between the jpegs. A couple notes for my own reference:
- Once the jpegs are ready, import the photos into iPhoto first, then from iPhoto to iMovie. If you go straight to iMovie, the order of the photos gets mixed up
- Set the frame rate by selecting the images and clicking the 'Inspector' button. Go to "Clip" settings and set the duration of the images.

iMovie would only let me go as high as 10 frames per second, but videos typically run at 30fps. I found that there's a powerful UNIX-based command line tool called ffmpeg which you can use to create these videos. Next time around, if my shots are looking more promising, I think I might put the effort in to using that tool to get a smoother video. The speed of the cloud movement was pretty good, so to balance out the increased framerate, I would try taking the pictures 5 seconds apart instead of 10.