Thursday, March 26, 2009

Digital ND Filter

Remember the post where we talked about dynamic range? Landscape photographs, and particularly photos of sunrises and sunsets, tend to have problems with the dynamic range of the scene. You have the bright sun and clouds in the background, but some darker details in the foreground, and your camera can't always capture both.

For simple compositions with bright sky on top and dark foreground on bottom, the traditional solution is to put a "graduated ND (Neutral Density) filter" on your camera lens. These filters are dark on top and clear on bottom, with a little gradient in the middle to smooth the transition. They let in less light on the top so that you can expose for the foreground without losing details in the sky.

The same effect can also be achieved using some Photoshop wizardry.

I took this photo in front of "Lake" Lagunita behind Stanford soon after we got our camera.

The sky and clouds are really stunning, but the foreground of the image is too dark for you to make out any details.

To apply the digital ND effect, I followed this great tutorial, written for the GIMP (GNU Image Manipulation Program), an open source alternative to Photoshop. The tutorial was well written and easy to follow, so I'm not going to re-write all of the details here. I think my post here should be helpful, though, in seeing the major steps and the overall effect.

I haven't thrown down the dough yet for Photoshop, so the GIMP is a good alternative in the meantime. If you don't have Photoshop, I highly recommend downloading the GIMP. It's interface is very similar to Photoshop, so any concepts or techniques you learn with the GIMP will translate easily to Photoshop down the line.

This effect takes advantage of the fundamental editing concept of layers and layer masks. I didn't have a good handle on these concepts until working on this image, but now they make perfect sense. I think this filter technique is a really good way to solidify your understanding of layers and layer masks.

Think of layers as a stack of transparent slides. The final image you see is what you would see if look down at the top of the stack. The idea is that each slide, or layer, will contribute something different to the final image. Separating it into layers means that you can make different adjustments to different parts of the image. You then apply layer masks to control the transparency of different parts of each layer. In other words, the layer masks let you specify which part of each layer will contribute to the final image.

Even if you don't go through the whole tutorial, I recommend reading through the section in the beginning "About Layers and Layer Masks". He explains it well and has some great images to demonstrate the concepts.

For this technique, we're going to duplicate the image so that we have two layers. We'll adjust one layer to make the ground look good, and the other layer to make the sky look good. We'll then apply a layer mask so that the sky layer only contributes its sky and the ground layer only contributes its ground.

I first created a layer for the ground and adjusted it to bring out the details in the foreground. To lighten the foreground, I adjusted the midpoint slider in the levels tool. The midpoint slider is a good way to lighten or darken an image because it does it without clipping off any parts of the histogram, which would cause you to lose detail.

You can see why the graduated filter is necessary here; lightening the image made the foreground look better, but it washed out the sky.

Next I selected the sky layer to punch up the clouds a bit. I used the midpoint slider in levels again.

This made the sky look even more stunning, but made the foreground even darker.

Note that in order to see the sky layer, I had to unclick the eye icon next to the Foreground layer. Currently the Foreground layer is completely opaque, so unless I hide it I can't see anything from the layer below it.

Now that I have my foreground looking how I want in the Foreground layer, and the sky looking how I want it in the Sky layer, it's time to combine them using a layer mask.

You right click on the layer to add a layer mask to it. Select the layer mask in the layers palette, then use the gradient tool to actually create the mask. You create the gradient by drawing a line on the image.

This mask modifies the top layer so that everything above the beginning (top) of the line will be 100% transparent, and everything below the end (bottom) of the line will be 100% opaque. The gradient will be along the line itself to create a smooth transition between the images in the two layers.

If you hide the bottom layer, you can see the effect of the mask clearly. The checkered areas represent transparent parts of the upper layer.

Once you make both layers visible, you have your combined image!

Here's the original again for comparison:

And that's it! If you're new to Photoshop, I think this is a really good beginning technique. It's helped me get a good grasp on the basics of working with layers, and made me much more confident working with the GIMP in general.

Wednesday, March 25, 2009


So a little bad news. Remember the wood chopping pic? Well, two weekends ago I set out to chop the last handful of logs in the pile, and on the first log, I missed the wedge and kind of squished my finger in between the sledge hammer's handle and the top of the wedge. It wasn't too terrible, but I did fracture it and it's been in a splint since then.

You know the finger you use to press your camera's shutter release? Yeah, it was that one (right index). So that's why I've been MIA for a while. The doctor said the splint should hopefully be off in a week or two, though.

I can't shoot anything, but I can still use a mouse! A broken finger tends to slow you down, so I haven't had as much time for photography stuff, but I have been sharpening my Photoshop skills a bit. I'll show you what I've been learning in my next post!

Tuesday, March 10, 2009

Goleta Beach

A week ago Friday I went out for another early morning photoshoot, this time out at Goleta Beach. I wanted to actually capture the sunrise this time, so I got up at 5:30am to try and get there a little before 6:00 (the sunrise that morning was at 6:20).

This post has taken me a long time! I've spent a lot of time agonizing over the pictures I took. There were really only one or two that I was excited about and I put a lot of effort into trying to edit the other decent photos into something interesting.

I found it really challenging to take a good landscape shot of the sunrise. I've talked to BurnBlue a couple times through e-mail, and he's given me some good advice on landscapes. In all of his shots, he tries to have something in the foreground, midground, and background. With beach shots, the foreground is typically some interesting rocks, and the background is the sky. I'm less sure of what constitues the midground, but I'm guessing that's the ocean. I think this advice makes a lot of sense--without subjects on these different planes, the picture looks flat and doesn't draw you in.

Thinking back to the shots I took, I'm not sure what I could have used as a good foreground, so perhaps that was part of my problem. I think this was the most interesting landscape shot I took, and that's probably because it has some interesting things up front: the car and the tree's silhouette.

I've probably spent the most time playing with this photo--trying different things with the colors, trying different crops. I think the problem with it is that there's too much going on. In a way there are two photos here. There's a nice photo of a car looking out to sea, and there's a photo of a beatiful tree silhouette. Having both subjects seems like too much.

I did actually take a photo of just the car, but I think it's basically pointed the wrong direction--it's on the right looking into land rather than on the left looking out to sea.

I tried something new on this photo, I used the graduated tint effect in Picasa to punch up the blue in the sky. It took me a few tries to get something nice that I didn't later decide looked overdone.

The photo I was most excited about was this one of a water spigot on the pier. I loved the light and shadows on the rough metal, and I had fun trying to capture the water drop mid-flight.

Check out the detail on that drop!

I think I've learned a valuable lesson from my frustration this past week. My editing skills are limited, and I was taking some shots that weren't that great to begin with and then trying to salvage them by applying techniques that I haven't mastered. Really, I should have just picked the photos that excited me (in this case just the one), and been ok with letting the rest go. It was valuable to try and self-critique these other photos to learn what I could do better next time, but trying to edit them into something good was just discouraging and exhausting.


There were a couple other fun stories from the weekend that I wanted to share.

After taking pictures at Goleta Beach, I went over to a friend's place to go jogging before work. He took me out along the coast to a part of Goleta I haven't really seen before. While we were out, we saw a whale a little ways off shore, blowing water and splashing around. We came across a couple researchers whose job it was to sit out on the bluffs from 9-5 everyday and monitor whale activity in the Santa Barbara Channel. They told us it was actually three grey whales out there mating (apparently it's not uncommon for two males to mate with a female)--I think they said it was around the peak of mating season. Sadly, I'm not in the habit of carrying my camera bag while jogging, so no pictures. Cool way to start the day, though!

The next day (Saturday), we went out to Santa Claus beach (perhaps it's so named to-highlight the irony of being able to go play at the beach on Christmas day?). While we were there, a handful of paragliders and one hangglider landed at the beach.

These crazy guys run off the mountains behind Santa Barbara with their chutes, float around for a while and eventually make their way down to land at the beach. I think the guy in these pictures actually botched his landing--he landed back in the shrubs between the train tracks and the beach. I'm assuming he didn't intend to do that because something about landing within thirty feet of a train with a big chute floating above you doesn't seem very safe.

Monday, March 9, 2009

My Journey So Far (Part I)

Photography has been a hobby of mine for about three years now. Since I'm using this blog to chronicle my current adventures and lessons, I figured it would be good to dedicate a post to my past experiences with photography that lead up to this blog. I probably wouldn't remember a lot of the details, except that I have photographs to document them!

There have been a number of events and lessons that I would consider big milestones in my journey, so I've organized the post around those milestones.

My interest in photography began in 2005, soon after my wife and I got married. My wife is an artist and designer, and studied art in college. We had had some fun experiences doing art together in the past--we took basic art together in high school--and I thought it would be fun to find an art form that we could both do together. We decided on photography; I probably had some interest in it, and I imagine the technical side of it appealed to me as well.

Milestone 1: Buying our Canon 20D
My wife had taken a photography course, so we knew at least a little bit about photography, and we knew that we wanted to get a digital SLR camera. So we purchased our Canon 20D which I'm using today.

I remember how exciting it was taking pictures of anything with it. The images were so sharp! And the shallower depth-of-field (less of the photo in focus) that you can achieve with an SLR lens has a way of making everything look more artistic.

Milestone 2: Learning the basics of manual exposure
The quality of even the most boring images was enough to spur my interest. I read through the first few chapters of the book for Jess' photography course, and learned all about the basics of focal length, aperture, shutter speed, and ISO. I enjoy the technical side of things, so I ate this stuff right up.

I misunderstood the significance of shooting in manual, though. I had it in my head that you can't take artistic pictures shooting full-auto, and that exposing manually was going to make a huge difference in my photos. Shooting in manual is not the secret to great photos, however; it just provides you with some important tools to work with.

Other than allowing you to control the exposure, shooting in manual essentially gives you control over two artistic tools:
  1. The "depth of field"--how much of the subject is in focus. This is controlled by the aperture.
  2. How any moving objects (people, animals, flowing water--or even the whole frame if you're holding the camera in your less-than-steady hands) are going to appear, blurred or crisp. This is controlled by the shutter speed.
You'll often want control over the exposure or over these two things, and so you'll want to understand your camera's manual controls. But getting the right depth of field isn't enough to make a great photo--as I mentioned in my last post, there's so much more to it, and I hadn't learned any of that yet.

We went out on a number of outings to take photos around Palo Alto. I didn't have a great handle on composition, and I hadn't learned yet how to look for good light outside. I was also still figuring out the photo editing process, which can involve a lot of floundering about when you're not sure what you're doing. I only went out shooting five times over the course of the first five months that we had the camera, so clearly the results weren't inspiring me to shoot much. I think we also found that going out and shooting together doesn't really work for us; we're inspired by different subjects.

That summer we took a trip to Amalfi, Italy and we took a lot of photos. If you go somewhere beautiful enough and take enough pictures, you're bound to get a few good ones. Even so, I love these photos and they've helped motivate me to keep trying.

Milestone 3: Flickr
In 2006 we both finished college and decided we really wanted to move down to Southern California. The job search went pretty slow, and we were actually planning on just moving to San Diego and continuing the search from there, but at the last minute I accepted a job with Texas Instruments here in Santa Barbara.

I took these photos from the SB court house clock tower. The photo stitching tool in Photoshop made that panorama incredibly easy--I was blown away by how smart it was.

Around then I discovered Flickr. The site is really well designed for discovering interesting work from different artists, as well as for getting your work seen and critiqued by other budding photographers.

So what's so great about it?

Inspiration - There are some amazing photos on Flickr, and it's hard not to be inspired by them. And let's face it, photography can be really hard and full of disappointment. Whenever I feel like giving up, looking at some great work can remind me of the awesome potential, and I find the drive to keep shooting.

Getting seen - Having a place where you can share your work, and have some hope of it being seen and appreciated, is very motivating. Flickr provides a lot of ways to share (and discover) photos. You can submit your photos to pools of similar photos, you can look at the "photo streams" of the people who comment on photos you like, and you can look at the collections of photos which other people have marked as favorites.

I'm sure there are other great uses for Flickr, but those are the two that keep me coming back to it the most.

The other milestones, interestingly, have all occurred pretty recently. But I'll share those in the second part of this post!