We Don't Need No Stinkin' Flash
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We Don’t Need No Stinkin’ Flash
Lesson 2b George Brown College “Night and Low Light Photography”
instructor Paul Till
• Flash looks like flash-not what you see already there.
• People notice flash-especially if they can’t see for a bit after you take photo.
• Wait for it…the inverse square law.
It doesn’t look like flash
How do I live without flash?
• Fast lenses, large apertures (focus carefully on just one thing)
• High ISO (and high noise)• Slowest usable shutter speed.(VR
[vibration reduction] helps and a tripod cures-but not if there’s subject motion)
The Trade Offs
• You can trade aperture, shutter speed and ISO for each other.
• Wide apertures. less depth of field(only one thing in focus, better focus carefully!), lens is less sharp.
• High ISO. More noise, degraded sharpness and quality.
• Slow shutter speeds. Unsharpness due to camera shake and subject motion.
The Trade Offs
• You (or on auto, the camera) will try to pick the best combination of shutter speed, aperture and ISO.
• e.g. f2 at a 1/60 at ISO 1600 or f2.8(don’t have to focus quite as well) at 1/30(might not hold camera steady enough) or f 2.8 at 1/60 at ISO 3200(more noise)
• Focus carefully on the place that you most want in focus.
• If the camera isn’t focusing make sure that the focus point has something with contrast to focus on.
• If you need to recompose hold the focus lock button.
• Push the shutter release before subject moves from were you’ve focused.
• Focus on a point where you hope the subject will soon be (zone focusing).
• Test the focus when using fast lenses, to to make sure you’re focusing well
• For a small distant subject, make sure you are focussing on it and not behind it.
• If there is enough light stop down a little to get a little more sharpness
Lens Sharpness-an asideA very rough guide to lens quality at different apertures
• As we stop down (make the aperture smaller) the depth of field consistently gets larger.
• That means we have a more margin of error for focusing.
• But as we stop down the lens quality(sharpness and number of other qualities) changes less consistently and differently for different lenses
• This is the general pattern as you stop down
My subjective view of f stops on a 50mm f2 lens (factoring in depth of field and sharpness)
• f2“Be careful! Use it if you have to (better than unsharp because of camera shake)”
• f2.8 “Better, but still be careful”• f4 “Much better but still focus carefully”• 5.6 “That’s pretty darn good”• f 8 “Oh yeah!”• f 11 “Too much of a good thing”• f16 “Only if I need the depth of field”• f 22 “I need tons of depth of field so I gotta”
More Lens Quality
• As a general pattern this is a good guide-wide open lowest quality, improves for 2 or 3 f stops levels out for a 2 fstops then decreases for each of the rest of the f stops but still stays better than the first two stops.
• The depth of field increases consitently and proportionally for each smaller f stop.
How Low Can You Go?
• Relax, hold the camera steady, breath out,gently push the shutter release
• The longer the focal length the higher the shutter speed needed
• Test yourself to get an idea of how low you can go.
Safe shutter speeds for hand holding(a guideline only)
Focal length Shutter speed DX (little) Shutter speed DX (full frame)
10mm 1/15sec 1/10sec
15mm 1/25sec 1/15sec
20mm 1/30 sec 1/20sec
24mm 1/40sec 1/25sec
28mm 1/50sec 1/30sec
35mm 1/60sec 1/40sec
50mm 1/80sec 1/50sec
85mm 1/125sec 1/80sec
105mm 1/160sec 1/100sec
135mm 1/200sec 1/120sec
200mm 1/300sec 1/200sec
300mm 1/500sec 1/300sec
Stopping subject motion
• The closer they are it is the faster they are
• (it’s degrees per second not miles per hour)
• The more at right angle to you the faster they are
• Moving the camera with the subject (panning) helps
Stopping motionguidelines only
• 1/10000 will stop streaming water into individual drops• 1/8000 will stop most any motion
• 1/4000 high enough speed to take pictures while walking/ and freeze baseballs ie. 90mph
• 1/2000 will stop most motion• 1/1000 will stop bicyclists and runners
• 1/500 will freeze a person jumping in the air ie. basketball• 1/250 will stop some motion• 1/125 will stop most walkers, runners, and cars in the background of a
picture, and will work well with panning
• 1/60th will work well with panning but runners arms and legs will be blurred• 1/30 can work with panning but runner’s arms and legs will be significantly
Stopping subject motion-a trick
• Wait for them or it to stop or slow down• Even for a fraction of a second
• If they jump up they have to stop to come down• Wait for the peak of motion• Allow for shutter delay• Practice
Going against the grain(or it sure is noisy here)
• Cameras go up to incredible ISO’s • The higher the ISO the more noise (just like
film!) (also definition and general quality go down)
• But some noise is uglier than film grain• Also affected by sensor model (they’ve gotten
less noisy with time), sensor size (bigger is better), pixel size(bigger is better), long exposures (1 second+),and heat
Reducing noise after you’ve got it
• Reducing noise- in camera setting (may only work with jpgs)
• In computer with Photoshop, Lightroom etc
• A stand alone program or plug in for Photoshop (e.g. Noise Ninja)
Reducing NoiseThe Trade offs
No Noise ReductionISO 3200(inset is whole photo)
Auto Noise Reduction(Noise Ninja)
Maximum Noise Reduction(Noise Ninja)
Selective Noise ReductionPlus selective levels
(Noise Ninja and Photoshop)
Learn this trick
• The brain looks for things that make the scene make sense and mentally highlights them
• The camera just looks at the tones-it doesn’t care what they are attached to
• Important picture elements must be separated by significant tonal differences and this is called…
• If black hair is as dark as the black sky behind it you can’t see where the head ends and the sky starts
• There’s no separation between head and sky.
• Look for something so the poor subject’s brains don’t leak out into the sky
For most people it’s mostly about the hair
• Hair is a light trap• In the light goes between the hairs and follicles but
yikes! It never comes out.• In the case of lighting from the front and a dark
background most hair will not show up well. Even darker blond hair will seem dark. If there are lights behind or from above it is a different story.
What to do about hair
• Look for a light behind the person or for any piece of lighter background-even if it is only a few square feet
• Then wait or move yourself (or move the subject)so the piece of background gives their hair separation
In the digital darkroom
• You can increase seperation if it’s there• The better the separation the easier it is
to increase it and have it look good (don’t underexpose)
• If there’s no separation you can put it in with lots and lots of Photoshop work.
Here’s some other questions to ask yourself
• Look at the light. Where is it brightest?• Where should you photograph from to make
the best use of the light?• Try squinting and seeing if your picture
makes sense?• Take the photo and review it. Does it make
sense if you don’t think about the actual scene where you are?