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Photography Tips: Manual Photography & The Munker-White Illusion

Skill Level: Professional


"Can You Trust Your Eyes" by ASAP Science
Check out their post here.

The good folks at ASAP Science posted an interesting video titled "Can You Trust Your Eyes?" In it, the narrator demonstrates how colors and tones will appear lighter or darker depending on what tone they're next to. As the video so eloquently illustrated, this phenomena - known as the Munker White illusion - can make tones that are actually the same brightness appear to be vastly different.

Photography Tips: Manual Photography and the Munker-White IllusionThe "A" column appears darker than the "B" column,
but in actuality, they are the same tone.

I teach a process for shooting in manual mode that depends heavily on the shooter's ability to analyze tones (covered in my How to Shoot in Full Manual online course here). So this video got me thinking about how we are basically doomed to make metering errors in our photography purely by nature of this illusion. No matter how experienced one may be in the manual metering process I teach or the somewhat similar Zone System by the great Ansel Adams, you will never escape this inherent failure of our eyes to accurately analyze tones.

Understanding this effect may not be vital information for the manual shooter, but it certainly couldn't hurt. For instance, let's say I'm spot metering off of a section of granite rock on a sunlit mountain side. And let's say the spot I'm choosing to meter off of is immediately adjacent to a dark patch of trees. In this situation I may analyze the tone of that granite to be about a +2/3 on my meter - in other words, I think that granite is just a shade lighter than middle tone. So I point my meter up to the mountain, line my meter up at +2/3, then recompose and take my photo. Everything comes out great.

But what if this spot was immediately adjacent to something light rather than that dark patch of trees? What if instead of the dark trees, there's a big swath of bright white snow next to it? According to this Munker-White illusion, I'll perceive my metered area as a different tone. When it's next to the trees, I perceive it as a shade lighter than middle tone (+2/3), but when it's next to the snow, I might perceive it as a shade darker than middle tone (maybe -2/3 or so). Of course, the rock hasn't changed its tone, it's purely my perception of the tone dependent on what tone it's next to.

Simply depending on what tone it's next to, I'll perceive my metered area differently and, thus, get a different exposure.

So this information may not fall in to the category of "photography tips" for everybody, but if you're an adroit user of your camera's light meter, you may want to be aware of this illusion. Try to block out the tones around your chosen spot meter area to avoid the trickery of this illusion. Here's one way to do it: just form your hand into a circle (like you're holding a pipe) then look through it like a telescope pointed at your chosen metering area. This will block out the surrounding tones and allow you to analyze the tonality of the subject untainted by the Munker-White illusion. Or if you don't want to look ridiculous, just spot meter off of tones that cover sufficient area to fill your viewfinder.

Photography Tips: Fixing Blurry Pictures

Skill Level: Beginner

Blurry pictures are one of the most common reasons a student will contact me for private lessons or an online photography course. It’s a problem as old as photography and still continues today despite all the technological advances with digital. Fixing blurry pictures involves changing the way you shoot, not getting new equipment or hoping Photoshop will undo the blur (it won’t). 

Often times a shooter will attribute their soft photos to their “crappy kit lens” or their entry-level camera. If only they had sharper glass and a better auto focus system, then blurry pictures would be a thing of the past. And with all the bloated lens reviews on the net comparing side-by-side images and MTF charts, it’s no wonder people assume lens sharpness is a big issue.

Well, it’s not. I can almost guarantee that your blurry photos are not blurry because of your lens. I have tons of students come to me with blurry photos and almost every single time, the blur is not due to a soft lens or bad focus.

Fixing Blurry Pictures

This photo is blurry (as can be seen in the 100% crop below)
but the culprit is not a bad lens or poor focus.
It's blurry because the shutter speed was too slow.

Fixing Blurry Pictures

When it comes to fixing blurry pictures, we first must establish that there are 2 basic types of blur in photography: out-of-focus blur and motion blur (let’s not get in to diffraction). Out-of-focus blur can be intentional and pleasing, like a blurry background in a portrait. Out-of-focus blur can also be unintentional and can ruin a shot. That would be like when the camera focuses on the wrong thing and so your subject goes out of focus.

Motion blur, on the other hand, comes from subject movement or camera shake during the exposure. And whether or not this results in blur is dependent on what shutter speed you use. You’ll get less motion blur with fast shutter speeds and more motion blur with slow shutter speeds.

In my thousands of hours of experience working with aspiring photographers, I can confidently say the number one reason for blurry photos is from camera shake at shutter speeds that are too slow. This is why blurry photos are especially common in low light scenarios, like indoors. The camera needs a slow shutter speed in low-light environments in order to create a correct exposure. Sometimes that’s the only way the camera can get enough light. But this slow shutter speed makes it nearly impossible to freeze camera shake and subject movement.

So the key to fixing blurry pictures caused by motion is to use a faster shutter speed. And how does one get a faster shutter speed? Well, it isn’t as simple as switching over to shutter priority mode and dialing in a faster shutter. You can’t take away light with a faster shutter speed unless you give the camera more light from the aperture or ISO.

To get your faster shutter speed, you must raise the ISO and/or open up the aperture. It’s that simple. Anytime the shutter speed is too slow, just raise the ISO or open the aperture and you’ll get a faster shutter. You may have to do this a few times. Lather, rinse, repeat.

Fixing Blurry Pictures

With a wider aperture and higher ISO,
my camera was able to use a faster shutter speed, 
resulting in a much sharper photo. 

Fixing Blurry Pictures

Now it may happen sometimes where you raise the ISO to its limit and you open the aperture all the way, and the shutter is still too slow. Now what? Well that’s why God gave us flash. Alternatively, you could get a new camera with a higher maximum ISO or a lens with a wider maximum aperture, but let’s not run out and drop a few grand on new gear just yet.

The bottom line is you need to know shutter speed, aperture, and ISO like the back of your hand. If you know those things well, you’ll be in complete control of motion blur and out-of-focus blur. That’s why I devote over half of my Introduction to DSLR Photography online course to shutter, aperture, and ISO. You really can’t know these things too well.

So next time you’re faced with blurry photos in low light, try raising the ISO and/or opening the aperture. Oh, and you sure as hell can’t be in full auto mode for this one!

UV or Skylight Filter: What’s the Difference?

UV or Skylight Filter

In the process of shopping for a UV filter, you may have come across something called a Skylight filter and wondered which one you should get: a UV or skylight filter.

The difference between a UV and skylight filter is subtle but notable: UV filters have no color cast to them. Skylight filters have a faint orangish-pink color cast. So UV filters are simply clear glass - that’s it. A skylight filter is just a UV filter dyed with a faint warm color tinge.

Why would you want a warm color tinge on a filter that will be on your camera all the time? Well, for the answer to that, we must go back. Way back. To the days of film! *gasp* Do they still even make film?!

UV or Skylight FilterSkylight Filter on the left, UV on the right
Notice the orangish-pink color cast on the skylight filter

Skylight filters were originally designed for use on traditional analog film and they really just don’t serve any purpose in digital photography. See, when shooting color transparency film like Fuji Velvia or Kodak Kodachrome, there is no adjusting color balance after snapping the shutter. In other words, it’s like the white balance was “baked in” to the film when it was manufactured. These films are usually manufactured with a “daylight” color balance - meaning they will get accurate colors in outdoor scenes in the sun, but not really under any other type of light source. Try using this “daylight” film indoors and you’ll get some seriously ugly yellow colors. Try to use it in the shade and your pictures will be too blue. There were also some films manufactured with an “incandescent” white balance for use indoors and those couldn’t be used outdoors without creating inaccurate colors.

So let’s say you have daylight film loaded in your camera, but you want to photograph someone in the shade. Well, that’s a bummer. Your film is designed for daylight, not shade. So if you take the photo, the picture will come out really blue.

What is a poor photographer to do?

Aha! What if we put yellowish-orange filter on the lens, then took the picture in the shade? The warm-tinged filter should cancel out the blue color cast from the shade, resulting in accurate colors.

Until digital photography hit the scene, this is how photographers would “adjust white balance” on color slide film before digital white balance existed. That’s why warming filters were so common. There was really no other way to adjust color balance than to use filters.

And this is why skylight filters were popular for shooters using color slide film. The faint warm color of the skylight filter helped to cancel out some of the blue created by an atmosphere rich in moisture. For example when photographing landscapes, often times distant subjects like a mountain range will turn out a little too blue on color slide film simply because there’s a lot of atmosphere between you and the mountains. But with a skylight filter, you’ll “cut through” that blue a little bit and get more accurate colors.

Plus, it just so happens that most (not all, but most) nature photography looks better if the colors are “warmed up” just a bit. Fall color, sunsets, sunrises - people tend to prefer warmer colors in these types of shots. So that’s another reason skylight filters were a common choice amongst outdoor photographers using slide film.

But with digital, it’s all replaced by white balance. There’s no need to use colored filters because a tweak to white balance creates the same effect. Rather than use a skylight filter or a warming filter, you could just use a “warmer” white balance setting, like cloudy instead of daylight, or shade instead of cloudy. Or better yet, just shoot RAW and tweak the WB in the computer. Want a little more warmth? No problem, just drag the slider.

So when it comes to digital, don’t bother with skylight filters. They will offer no benefit over UV filters. And besides, if your camera is set to auto white balance, the white balance will just cancel out the warm colors of the skylight filter anyway.

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