Posts tagged “DOF

Where Everybody Knows Your Name

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Cheers! 17mm, f/10, 6 exp, ISO 100

Had lunch at the basement bar in Cheers on Beacon Street in Boston — the inspiration for the TV show and the place you see when they would show the outside shots.  It was a tiny little place and spots at the bar were coveted but I happened to come in at just the right time to get a spot.  There was also an upstairs bar which mimics the set of the show but frankly the room had none of the feel of what the show looked like…not very impressive.  Downstairs was the place to be.  While waiting for my food I set the camera on the bar and fired off some brackets.  Even though I used f/10 the DOF is really shallow due to the close focus distance.  I didn’t want super long shutter times given the movement of the bartender and the people seated on the other side.  f/10 was a decent balance (I shot brackets at f/4 and f/22 also and later picked what I liked the best).

In the gift shop they had this infant onesy.  Pretty funny when you think of the words to the theme song.

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Two of My Boys: Bokeh Panorama

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Two of My Boys: Bokeh Panorama 50mm, f/1.4, 1/640s, ISO 100,14 frames...sort of

[Update: Here’s another try at it]

This evening I photographed my youngest boys in the backyard with the goal of trying out something called the Brenizer Method, or bokeh panorama.  I first heard of it in a post by Brandon Brasseaux. The goal of the Brenizer Method is to create an image with extremely shallow depth of field.  If I were to take the shot above using a single frame I would either (1) use a very wide-angle lens or (2) use a “normal” lens and stand far back from the scene.  In either case it would be difficult to get much bokeh in the image.  I’ll let you consult a depth-of-field calculator for the exact details but suffice it to say that the wide-angle lens — even at an aperture of f/1.8 — doesn’t result in much bokeh when focused at any reasonable distance.  A lens like I was using in this shot — a 50mm f/1.4 — would require such a long focus distance (i.e. I’d have to stand so far back) that the depth of field would large enough to eliminate a lot of bokeh.  The Brenizer Method uses multiple frames to form the image — using a much shorter focus distance resulting in much shallower depth of field than if you shot one frame standing further from the subject.

The process goes as follows: Instead of standing far away, stand close (I roughly filled the frame with the two boys).  I used an aperture of f/1.4 to get the shallowest depth of field and set a shutter speed in manual mode to keep the exposure consistent in all the frames (I also set the camera to daylight white balance).  I prefocused on the boys and switched the lens to manual focus.  The first frame I took was the one with the boys in it (took many tries to get something decent).  I then let them run off and proceeded to shoot overlapping frames (with the camera in the same location) of the rest of the scene you see above.  I used 14 straight-out-of-the-camera frames to stitch the panorama in Photoshop but in the end I cropped the image quite a bit. It took all of two minutes to shoot the frames, even with the boys’ goofing off.  Since my goal was to try out the method itself, I didn’t stress about background, lens flare, etc.

After stitching I warmed the image a bit, added vignette, tweaked the exposure/clarity on the boys, and removed some of the color fringing on the branches so it wasn’t *so* prominent.  Pretty simple stuff.  I want to try more of these but next time I’ll find a prettier background.  I believe I’ve given enough info for one to start playing with it but if not, an internet search will turn up a lot more information in a hurry.

Here’s a link to posts by the man behind it all: http://www.ryanbrenizer.com/category/brenizer-method/


Hand Made Christmas Ornaments

2009 (painted on the side of the mailbox) 35mm, f/22

Each year my mom sends hand-made Christmas ornaments to family and friends.  They are usually very intricate in both structure and painting.  It’s a bit harder now with our large family size but ours are typically personalized with our first names painted on the ornament.  She does exceptional work on crafts like this.  We always encouraged her to make a business out of her various crafty things but she was never interested.

Before the tree came down this year I decided to grab quick shots of some of the ornaments.  While the crafts stand on their own artistically I’ll throw out a few comments on how I shot them.  First off, I didn’t light them except with the lights on the tree and the ambient (tungsten) light in the room.  I used a tripod and bracketed the shots thinking that I might even do some HDRs given the large difference between the shadows and the lights on the tree.  In the end the only HDR is shown at the top of the post…it’s just OK photographically IMO.  I didn’t spend any time in Photoshop trying to make it better.  I experimented with aperture.  I didn’t get enough DOF with f/2.8 — even when considering only the ornaments and not the tree and lights.  Using f/22 gave interesting starbursts in the lights of course but required either very long shutter speeds at low ISO or a higher ISO which I avoided since I was planning on HDRs.  Of course I could use any shutter speed I wanted but I was simply too lazy to do manual exposures/bracketing above the 30 second maximum sans “bulb” mode.  I didn’t want to do starburst HDRs that badly.  So, I ended up processing individual frames with apertures ranging from f/6.3 to get some bokeh vs. f/22 to get the starburst effect.  Lightroom was used for some simple adjustments — mainly clarity, contrast, sharpening, and vignette.  A variety of combinations are posted here.

For purposes of scale here’s a (blurry) picture of the above ornament with a quarter held next to it.  Other ornaments are shown below.

2003

The Texas ornament is not hand-made...


Strolling on the Beach

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Strolling On The Beach 50mm, f/2, 1/4000s, ISO 100

I was very surprised to find that one of my (not-so-freshly-pressed) posts was featured on WordPress Freshly Pressed. I started thinking about what post I should follow up with to hopefully meet the expectations of any new followers, etc.  I’m humble enough to realize that I’ve got nothing but photographs that *I* like — and hopefully others will like many of them.  What’s the Ansel Adams quote?  Something like “There no rules for good photographs, only good photographs”.  And of course “good” is defined by personal taste.  So…I’m just posting the next picture I had already planned to post in hopes that others like it too 🙂

On a recent trip to the Texas coast I was setting up for some bokeh shots with the 50mm f/1.4 and noticed this couple approaching.  I quickly focused on the sand and recomposed to catch them as they passed in front of the camera.  I said a quick ‘hello’ but otherwise pretended to ignore them and clicked off a couple of shots as they were in the frame.

My camera was already at what I considered a good aperture for this situation — f/2.  From experience I knew that anything larger and the background would be too blurred to provide enough detail to give a sense of where the shot was taken.  I had already experimented with some f/1.4 shots taken at a very close distance from the subject and the background was completely lost.  For all you could tell, I was in a bright room inside my house as opposed to the beach.  Sometimes that’s a nice effect but when I’m at the beach I typically want to show, or at the very least hint strongly, that I’m at the beach.

I knew my focus wouldn’t be perfect.  With such a shallow depth of field it usually doesn’t work to recompose your image since you end up swinging the whole plane of focus away from the subject [see below for a short, lame-ish explanation of that].  I had no time to worry about that nor did I care for this shot since I didn’t really want to capture any detail of the couple — I was going for the overall scene of “some couple” walking on the beach.  With the blown-out highlights and backlighting a precise point of focus wasn’t going to matter much anyway.  I’m not wild about the composition but again, this was a hurried, serendipitous shot.  The almost-opaque frame around the image was something I added while experimenting with OnOne Software’s Photoframe.  I’m not sure if I like it but I’m considering this one “done”.

About those depth of field issues when recomposing a shot…When you focus your camera on a particular point, imagine a plane that is perpendicular to line between your lens and subject.  Everything on that plane (including everything near the plane within the range of your chosen depth of field) will be in focus.  Taking that further, if you focus on a subject 10 feet away it will obviously be in focus, but so will anything on the flat plane (NOT arc) which goes left and right from that point.  [Here’s an illustration — not sure how helpful]  When you focus and then rotate the camera (recompose) that whole plane moves.  If you have a large depth of field (ie small aperture and/or fairly large distance to the focus point) that may not matter because the subject remains within the in-focus region even when you rotate the plane.  If the depth of field is very narrow there’s a good chance that you end up moving the subject out of the in-focus region (actually you move the plane of focus away from the subject as you rotate it).  I’ve seen a great illustration of this somewhere…I’m not able to find it with a couple quick internet searches though.


Out of Focus. Sort of…

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Former Flower 60mm, f/2.8, 1/2000, ISO 200

I shot this on a hike in Montana this summer.  Initially I just thought it would make a nice shot with a blurred background — usual stuff.  However, when I started shooting it I realized that no matter what I focused on within this “flower” it still appeared out of focus somewhat.  There’s so much going on in there that the shallow depth of field blurs out the rest.  I kind of like how it sort of has a focal point, yet sort of doesn’t.

Just for grins, another shot from the hike:

http://www.flickr.com/photos/michaeltuuk/6304473358/in/photostream/

Flower 70mm, f/2.8, 1/350, ISO 200


Capitol Star

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Star in the Capitol Gate

I always liked the stars that adorn the gates and fences on the Texas Capitol grounds.  I played with variations of this shot for a while but couldn’t seem to capture what I really had in mind — both the star and the Capitol in focus, with this perspective.  The formula may exist but I didn’t figure it out.  The wide-angle lens (used for this shot) gave a perfect perspective but I had to use a focus distance which precluded a deep depth-of-field.   Stepping back with the wide lens pulled in some out-of-balance elements (IMO) of the gate unless I centered the star (blocking the Capitol building). Tried the 24-70mm but the bit of added compression in perspective wasn’t quite to my liking.  That compression does help square up the star and Capitol relative to each other but again, it wasn’t what I was after.

I decided to post the shot anyway — still an interesting shot IMO and I hope you enjoy it.  It’s interesting how the tonemapping process turns the background blur into a somewhat dreamy scene while keeping the star a nice, realistic focus point.  I might experiment with this shot again someday.


Depth Of Field…Not Simply Determined By Aperture

Understanding depth of field (DOF) is one of the keys to great photographs.  Having too shallow a DOF can result in important subjects being out of focus.  A very deep DOF may result in background distractions — areas that you intended to be out of focus may be sharp and detract from your subject.

For a long time I thought that the only thing to know was “large aperture = shallow DOF”.  However, in addition to aperture, DOF depends on many other factors like the focal length of the lens, the size of your camera’s sensor, and the distance to the subject you are focusing on.

I have no intention to discuss the equations and physics which govern DOF here.  If you find that interesting then search for articles on a site such as photo.net.  What I will do is give a few examples of what to expect with certain settings.  All the calculations come from dofmaster.com.  I use their iPhone app — quite handy.  Google “DOF calculator” or search the iPhone app store to find other programs if you’d like.

Let’s assume you are using a Canon 50D (my current camera) with the trusty 50mm f/1.8 lens.  If your subject is 5 feet away (that’s your “focus distance”) and you’re shooting at f/2.8, whatever is between 4.85 feet and 5.16 feet will be in focus (roughly 4 inches).  In a portrait situation this implies that if the eye is in focus, the tip of nose will barely be in focus (depends on the size of the nose 🙂 ).  The back of the ear may be out of focus a bit.  If you stepped back to a distance of 20 feet (granted this will be an entirely different composition) you now will be in focus from 17.7 feet to 23 feet — total DOF of over 5 feet.  Note that this depth is obtained using the same lens and aperture as the portrait above but the DOF is different due to the focus distance.

Here’s a shot taken with a 50mm lens, f/2.0, approximate distance was 6 feet which gives a total DOF of only a few inches.  The near eye was my focus point.  Note how the rear eye and cheek are already a bit out of focus (I like it).

Elaina

Impromptu Portrait of Elaina

Here’s a shot taken with the same 50mm lens at f/4.5 (reasonably large aperture) but with a large focus distance.  Everything is in focus from the front of the car to the sign behind it.

VW Bug

VW Bug at Magnolia Cafe South

Let’s look at an example using a smaller aperture.  Most of us would consider f/7.1 to be a reasonably small aperture and expect this to give “good” DOF.  If you are focusing on a single person at a distance of 10 feet, they will be nice and sharp.  However, your total DOF is only about 3 feet.  If you were shooting into a crowd at this distance you would only be focused at a depth equivalent to a few people.

Five

Elijah Is Five Today!

In the above image of Elijah, a 28mm focal length at f/7.1 gives exactly the effect I intended.  The hand is in focus and prominent due to the wide angle, his face is blurred but still very much recognizable and part of the picture, and the distant background is quite blurred.  Someday I’ll photoshop the kiddie pool out of the background…

So — pay attention to DOF and know how it will affect your images.

There’s a LOT more to know.  I’ve ignored the fact that DOF is constant in a *plane* rather than simply a radius from the lens.  I’ve not explained hyperfocal distance.  Research and learn the basics at least.  You may avoid the disappointment of finding out your small aperture didn’t give you much DOF or that your large aperture didn’t blur the background like you thought it would do.

© 2009 Michael Tuuk

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