Cosplay Photography – THE SCIENCE SLIDES

As per request, here’s the sciencey basic slides from my Cosplay Photography panel, hope it comes in as a handy (lengthy..) reference, or at least you get to laugh at how little I UNDERSTAND ANYTHING, or something.

Imagine the entirety of this text read to you very quickly with maniacal hand gestures.

A perfectly accurate diagram of how your average DSLR works.

The reason they make a racket over compact cameras is that whole mirror assembly is mechanically yanked out of the way, before the two shutters do their thing, then slammed back down again, all in the blink of an eye.  This is done so you can see exactly what the camera does, optically, no electronics between you and what’s Through The Lens (TTL), this is why they’re known as Single Lens Reflex, the alternative is Twin Lens Reflex which is how older cameras did things, with a viewfinder that just kind of showed you roughly where the main lens was looking..

So why two shutters?  There’s the magic right there. Imagine if there was only one shutter, and remember we’re working with speeds of thousands of a second here, no matter how fast it gets out of the way, one end of the sensor would get exposed before the other, and as the shutter has to come back to cut off the light, that same side still gets more as it’s the last part to be covered!  You’d end up with a gradient of light across the picture.  With two, the second gets out of the way in advance, then the first goes the opposite way, and the second follows it, cutting off light from the direction that first recieved it!  Clever.  Even cleverer, is to get shutter speeds faster than 1/200 of a second, the Second Curtain starts closing before the first has even cleared the sensor!  So only a thin slit is actually visible at any given fraction of a second. This is why flashes can only sync at 1/200s and no faster, even though flashes are waaay faster, they would only light up that thin slit giving very odd results!

So what about compacts?  Strip out the mirror and shutters, and have that sensor ALWAYS ON, pumping a feed back to the LCD screen, this is why compacts have vastly inferior battery life and quality suffers, the sensor has to be always on and not overheating, while a dslr’s sensor only need be on for a fraction of the time, and can get away with doing things faster and hotter.  I used to use a compact for convention photography (Gotta start somewhere, right?), I’d go through at least four (Li-ion) batteries a day, sometimes more after recharging them during the day.. With my DSLR even going all-out and taking a good 2-3000 photos in a day, I’ll have used maybe one and a half batteries, sometimes two.

THE MODES YOU WILL NEED

Basically the sooner you force yourself onto Manual the quicker you’ll learn this stuff. there’s no shame in using auto modes if you can’t get it how you want or are handing it to a friend or whatever, but give M a chance whenever you can really.

Reason being, automatic modes take control away from you, the photo becomes more of a best guess on the camera’s part rather than your own, and it can be quite tricky to tweak anything if you think something needs changing.  Also, the camera can be wrong, very wrong at times!  Shooting in odd or changing lighting conditions very quickly confuses the sensor and gives a lot of misreadings.

Aperture Priority and Shutter Priority (Av and Tv on Canon cameras) are useful at times, they allow you to fix the Aperture or Shutter Speed and automate the rest, very useful in situations where you know the lighting will be changing quicker than you can keep up with, but you don’t want to lose all control.  ISO can be fixed at any time in most modes.

THE MOST IMPORTANT BUTTON

Nearly all modern cameras, even compacts and even some phone cameras, have a two-stage shutter release.  That means it has a half-press sensor, if you press the button roughly halfway down you should feel the camera whirr away but not take a picture.  This is when all auto-focusing, metering and decision-making happens inside the camera, once finished they will remain fixed for as long as you keep it half-pressed.  Typically if you fully press to then take a picture and release back to half without fully releasing, the settings will still be kept.

Not only is this handy for keeping settings, or for fooling automatic cameras into picking different settings it wouldn’t usually, it’s ideal simply for getting that second or so of calculations out of the way, so when the magic moment happens, pressing the button the rest of the way actually takes the picture THAT INSTANT, instead of faffing around with all of that before taking it.  Plenty of times I’ve seen people squeeze the button, be confused at why it’s taking more than a split second to work, and squeeze harder and harder, even tilting the camera or shaking wildly from the pressure before the shutter finally goes off!

Best practice: half-press in advance. Waiting for a group of people to settle down? Halfpress. Waiting for the cosplayer to tweak her wig before posing? Halfpress.  If they move sufficiently or something changes, let go, and halfpress again.  This means the INSTANT you see the perfect shot, press the rest of the way and you will get it.  Otherwise you may miss it by precious seconds while your camera autofocuses!

So here’s the back of a standardish DSLR, a Canon 450d to be exact in this case.  The smaller view is what you’d see through the viewfinder, a tiny heads-up (or down?) display below the image.

Now there’s a lot of scary numbers there, and that’s what puts most people off.. However, they’re not actually all that bad!  So what do they mean?

These are the three Big Numbers, the main three that actually matter, Shutter Speed, Aperture and ISO.  They make up the Exposure of your image, that is to say how bright the picture comes out. Too dark, and it’s called Under-exposed, too bright, Over-exposed.  The balance between these three settings determines how your picture will come out.

Exposure is measured relatively, and expressed as a doubling or halving of light, also known as a Stop, light isn’t measured in exact terms with photography unless you have a light meter, it’s simply expressed as needing x stops more or less exposure to get where you want to be, cameras often measure things in 1/2 or 1/3rd stops to give you extra control.  If you see something that says eV or +1, +2 etc, it’s talking about Exposure Value, which is just a number of stops. (i.e. -1 eV is one stop less, and thus half the light, of 0 eV)

Long story short, if something is too dark, and for some reason you’re rich and famous and are ordering around an intern to change the settings instead of doing them yourself, you’d say to change a setting by a number of stops, to brighten it. All three can be measured in stops, let’s see how!

 

So Shutter Speed, well it’s reasonably obvious, the length of time the shutter is open and exposing the sensor to light; the faster it is, the less light gets past.  Double the speed, halve the amount of light that gets in!

So if you’re at 1/400s, that’s a four-hundredth of a second, adding a stop of exposure would mean halving the speed, so 1/200s, to add another stop, 1/100s and so on.

Basically faster = darker, pretty simple.  So why not go all the way slow?   Well things moving quickly will blur at low shutter speeds, and when you start getting down to 1/80 and 1/60, camera shake from your own hands will start to have an effect on your shots.  If you’re stable, hold the camera well, brace against something solid, breathe properly, squeeze the shutter release rather than press, and so on, then you can achieve lower speeds without too much motion blur, but for more reliable results you want to be above that 1/60 mark!

Quick example, 1/100 is clearly too fast in this rubbish light.. 1/25 we’re starting to get an image there, but to give an idea of how lucky even that shot is (and how still Angelphie is having to stand in the middle of a cold March night in the Southampton docklands while dangling two lights on chains), on the end there is 1/25 if you jog the camera at all, look at that crazy amount of blur! That’s how much you would have to try and hold still in that space of time!  Or if our Velvet here had moved at all even a fraction, we’d see something more like the third picture.

Okay the second Big Number, ISO Speed

Don’t ask what ISO stands for, it’s not worth getting into.  It’s just there. Call it Ice-so, I.S.O, whatever you like.

This is how sensitive your sensor is to light, and relates directly to ISO speed of actual camera film.  Think of it like a percentage, ISO 100 is 100% reactive to light, ISO 200 is 200%, and so on.  The more sensitive your sensor however, the more noise will creep in.  Low light and slow shutter speeds also increase the chance of noise, but as you can see on the scale there, it gets progressively worse so be careful with how high you go!

The lower strips are just photos of a wall in my bedroom, where a white painted wall hits a black paper border, and the final strip at the bottom is some quick contrast processing to show that even though at a glance the noise isn’t all that bad, should you want to do any filtering or processing, it will quickly become the bane of your life.

So back to stops, again pretty easy here.. Twice the sensitivity = twice the exposure, thus, one stop. ISO goes up in stops anyway (100, 200, 400, 800, 1600, etc) so it’s easy to use.

Ideally you want to shoot as low an ISO as you can get away with.. Outdoors in bright light, 100 all the way, indoors you will be forced to use more in the region of 400 if bright to 800, 1600 and up if not, at that area you’re going to need to start thinking about flash as noise will be getting kinda heavy.

Quick examples, both photos look pretty good at a distance, but up close? DIFFERENT STORY

More megapixels on your camera do actually help here to an extent, if you’re resizing your photos for web use, the bigger they started as, the more the noise will be covered, but don’t rely on this.  Noise reduction tools can save your bacon but they tend to give skin a plasticy HELLO IVE BEEN PHOTOSHOPPED look if you’re not careful.

 

Right, Aperture.

This is the hard one to explain.

This is how wide or narrow the iris in your lens opens when you take a picture, in relation to the focal length of your lens. Make sense? No? Tough.

Basically, there’s a Scifi-looking device inside your lens that opens and closes to make a wider or smaller hole, it’s written as a number with an f, like f/2 or f/5.6, also sometimes written 1/5.6 or 1:5.6, this is because it’s actually a ratio, and this is where it gets real confusing.

The larger the f/ number, the smaller the ratio (1/4 is smaller than 1/2), so when people say larger aperture, which do they mean? a larger number (smaller hole) or a larger hole (smaller number)? AGH!   To avoid confusion, use the terms narrower and wider, to show you mean the hole itself, not the number. ‘Wide-open’ is a term often used to mean the lowest f/ number your lens can handle.  Your average comes-with-camera lens can only go as wide as f/3.5 when zoomed out, and f/5.6 when zoomed in (remember it’s a ratio of focal length, same size hole but longer zoom = smaller ratio!) but the magical cheap 50mm prime (no zoom) lens you can get for most camera makes that I thoroughly recommend goes all the way to f/1.8

 

HELLO MATHS, HOW’S IT GOING?

So this is where the scale comes from, it’s the distance between sensor and the end of your lens (focal length) vs the diameter of the iris, expressed in powers of root 2.

Got that? No? That’s fine. You really, really don’t need to know that.  But if I didn’t tell you, you’d wonder where all these magic numbers come from. Now you know, you don’t need to care!

What you might care about is what those numbers do!  Every step along that scale is a stop, so 1.0 to 1.4 is half the light.. f/1 all the way down to f/22 is 512 times less light! Easiest way to remember is double the aperture f/number = 2 stops less = 4x less light

Again cameras will break this down into half and third-stops for you so you’ll see other numbers in between these.  At the end of the day you only need to know wider aperture = smaller f/ number = brighter.

And here’s the proof!  Smaller hole = darker picture.. and if you look on the right where I’ve set it to balance out the darkness by automating shutter speed you can see the maths really does work.. One stop down the f/ scale on aperture means the shutter speed halves exactly to keep the same amount of light coming in!

Now here’s the magical part, look down the scale on the right, notice how at the lower end both figurines are in focus but with a wider aperture the rear one is blurred?  Welcome to the magical world of bokeh.

Aperture changes your depth of field as well as how much light gets in, that is to say the region in which things are sharp-focused, changes size.  The wider your aperture, the smaller the depth of field, and vice versa.  It’s how shiny cameras get that blurry background effect like so:

So pretty!  Also useful for blurring ugly crowds and background clutter out of existence!  Some say it gets abused but it’s perfectly acceptable for cosplay photography, and solves many an issue with slightly unhelpful backgrounds!

But it’s not always optimal:

Here we can see Ichigo-chan in the MinamiCon studio, up top I went for a wide aperture and while she’s perfectly in focus you can see the edge of her skirt which is in front of her, is slightly blurry.. Down below at a much narrower aperture, it’s all in focus.

As a general rule, if you have enough light to do it (and you often won’t) f/8 is considered optimally sharp

Sometimes this is merely personal preference, however:

Here’s how to get it wrong!

It’s usually trivial to focus on a single cosplayer, two or more and not standing right beside each other, and it’s much harder for wide apertures!  In the first clearly there’s a huge distance between Angelphie and Ashechan so it’s not surprising that our  Tinkerbell is considered part of the background by the camera!  but down below there’s no more than a meter between them, yet she’s still out of focus!

Well..

The other thing that effects depth of field, is distance from subject!  Tricky to explain but the further away you are from what you’re focusing on, the deeper the field in which things will be sharp. Have I lost you?

Okay take the above pictures, at f/1.8 which is pretty damn wide, I’ve focused on Delusional in the front there, Amy-Lou at the back is blurred out of existence!  Second photo I’ve focused on Amy-Lou and now Delusional is blurred – however notice that the building in the background seems to be in focus?  Yet the distance between it and Amy-Lou is reasonably close to the distance between her and Delusional.. So what gives?

Because I’m focused on something further away, the range is larger, if I physically get myself much further away from both of them and focus again, I get both in focus! Hence the third photo, the picture up top is the actual photo taken, but cropped down and it looks the same as my previous two, but with two in-focus cosplayers rather than only one!

Lesson here is: if you can’t get all your cosplayers in focus, you need to either narrow your aperture, or get further away and zoom in/crop your image!

So!  That’s all three Big Numbers explained, back to what they mean.  You can now see the balance we have, to get a correct exposure, not too bright, not too dark, just right for Goldilocks, you need to juggle those three numbers, and at each bright end of their scales is a downside, noise, motion blur, and small depth-of-field.  Small depth of field isn’t always a minus so that’s another reason it gets used a lot, it makes juggling these easier!

So, take a photo. Look at it, what do you feel is wrong with it?

Too bright? Raise shutter speed, narrow aperture or lower ISO until happy

Too dark? Lower shutter speed, widen aperture or raise ISO until happy

Too noisy? Lower ISO, and widen aperture or lower shutter speed to compensate

Too blurry? Raise shutter speed, and increase ISO or widen aperture to compensate

Not enough in focus? Narrow aperture, increase ISO or lower shutter speed to compensate

Too much in focus? Widen aperture, decrease ISO or raise shutter speed to compensate

etc, etc.

 

And here’s where those numbers go!  Shutter speed usually gets the largest sized font, and is typically written 1/100 or so, Aperture is usually the number next to it, written f/5.6 or similar, and ISO usually has ISO written next to it, and is always in steps of 100, 200, 400, etc (some cameras auto modes will pick values inbetween these and use interpolation to munge these values, this can be a blessing and curse)

You’ll notice on the end there, most compacts won’t tell you or let you set shutter speed or aperture! That’s two of the three numbers!  They may flash up when half-pressing or after taking one but you don’t get to set them, only influence them with some tricks we’ll get to soon.

There’s also White Balance, usually seen set to Auto but we’ll get to that.

Finally, an exposure meter. Wait, a what?

So I’ve talked about how the Three Big Numbers make up your exposure, so what’s this?  This is a meter showing you how balanced your exposure is! How handy!  It’s the closest thing you have to a built-in light meter.

If your camera is a compact or a DSLR set to auto, it will automatically play with the Big Numbers, and settle on what it thinks looks good, that’s what it’s supposed to do of course.  What this meter does is tell you what that automatic metering thinks of you and your current view!  A marker on 0 means it thinks you’ve nailed the exposure dead on, if it was on -1 it thinks you’re one stop too low and should double the light you’ve got, +1 is a stop too bright, and so on.

Bear in mind, cameras make many mistakes and it depends on how you’ve set the camera up too!  Still, because you’re in Manual, take a picture, see what it looks like, and change your settings accordingly – use this meter merely as a guide.

Okay I haven’t forgotten about those of you with compact cameras!  You won’t have a manual mode, so are you lost? Adrift? NO! You get to play with this, Exposure Compensation!  Just as the camera aims to change the numbers to hit the magical 0, if you decide the camera has made a mistake and is going too dark, change this here to make your camera aim for your marker instead of 0!  So +1 means the camera will do it’s guesswork, then aim for one stop higher than it thinks, because you know better.

This is invaluable if your camera doesn’t like to play ball often, if you know the lighting is crazy and your camera will go WOAH TOO DARK TIME TO BRIGHTEN EVERYTHING, whack that slider down low and force it to keep its shutter speed nice and fast so you don’t get blur.

Remember automatic modes play it safe, they focus on getting a picture bright enough to see, their main use is for people taking snapshots of places or friends who’re standing still for a pose, they’ll happily pick low shutter speeds if it means getting the brightness it wants!

THAT’S NOT ALL! Even on DSLRs, if you stick the flash on, suddenly you have another variable in your exposure calculations, as flashes are highly automatic unless you know what you’re doing.  Fiddling with shutter speed when flashes go at thousands of a second isn’t going to do anything, so many cameras will have a Flash Exposure Compensation meter for you to play with, and force that flash to aim a little higher or lower than normal.

This is a typical AutoFocus point system in a DSLR, that is to say these dots are where the camera will look for things to focus on!  This is also where Face Detection comes in for compacts, if it spots a face it will figure you want to focus on that since generally, you do!

As usual, automation leads to potential errors!  If in doubt, get that sucker in manual.  Find if your camera supports Spot Focus or Partial Focus/Metering, this tells the camera to use the middle of your view to base its guesswork on.  Spot in particular tells it to use only the dots above.  Now, find the option to select a specific dot and you’re away!

I generally go with the centre dot, this means whenever I half-press that shutter button it will autofocus on whatever I point that centre dot at, nothing else.  It’s best if shooting people, to aim that dot at their eyes, as a rule of thumb that’s the place a misfocus will show the worst, so aim there.

What if you don’t want your focused thing in the middle of your picture?

I’M GLAD I PRETENDED YOU ASKED

Remember all that halfpress malarkey I made you pay attention to?  Here’s its raison detre right here.

Point at what you want to focus on, half press, hold there, move back to where you want to frame your shot, finish pressing! EASY

Similar goes for metering, if the meter is all haywire because of what’s in your view (TV screens or bright lights in the background cause havoc for this), point away and at something you think should be neutrally-lit (ie not the brightest thing, not the darkest, somewhere in the middle), half press, now change settings until you hit the magic 0, now you can let go, recompose your shot and ignore the meter as it goes nuts and you take your shot, you’ve already worked out where your settings needed to be!

So what’s all this then?

Light isn’t white, most of the time.  Natural daylight has a slight blue tint to it, due to the atmosphere, while most indoor lights are tungsten, and have a warm orange glow to them, flourescent lights (ie strip lights) are closer to white but have their own odd hue, and that outdoor light? that actually changes depending on cloud cover and time of day.. Only Flashes or specifically designed lighting will be pure white.  Most stage lights will be orange, but spotlights or some floodlights will be pure white, this can cause major headaches if there’s a mixture!

Now for 80-90% of shots, Automatic White Balance is fine, even if it’s not spot on it’s good enough to not really mind, or to tweak easily enough even when shooting JPEG, but for odd cases or because you want to take a load off your camera from having to guess white balance for every shot, you can manually pick a setting like above.  As you can see getting it wrong looks really, really bad!  Setting it manually then going from one area to another, indoors to outdoors or vice versa will have the worst effect which is another vote in favour of automatic, but as always, automatic isn’t perfect.

(Worth noting that in automatic mode, if you use flash it will automatically pick Flash as the white balance (pure white) so if you’re doing some long exposure fanciness or using gels where the light will be coloured still, remember to manually force a setting other than Flash or Automatic, it won’t detect one for you)

I mentioned gels there, a bit advanced but you can get coloured strips of plastic or acetate to stick over your flash, these either dampen or colour the light coming out of it and can be used for a variety of things, but I won’t cover them here.

A handy tip from Ashechan: when outdoors in daytime leave your camera set to Cloudy, you typically get warmer, richer colours even when it isn’t cloudy. Your mileage may vary of course but it works for me.

So if all the above presets fail you, or you know you’re going to have troubles, there’s a Manual Mode!  Find something neutrally grey, many photography related accessories are a particular shade of grey called 18% grey, you can even get cards in that specific colour just for this, but any sort of pure grey/white/black view will do, there just needs to be no natural colour in the middle 30% of your view, only black, white, or preferably grey. Take a picture, and set your Manual White Balance to that picture, it will look at the grey, read all the coloured tints on it from the lights and WORK MAGICAL WONDERS to get you the perfect balance. Assuming the lighting doesn’t change.

This is great if you’re shooting in a studio or a Masquerade where the lighting won’t change colour, get someone to stand where the cosplayers would, and hold up a grey card or similar, so you can fix your colour settings ready for the entire procession!

THE HOLY WAR

Personal preference, basically. The image above I shot in both at the same time, I then took each and tried to process the maximum exposure out of both of them (2 stops) and took a look at the results, this is where the most noise and degredation should be clear.

RAW is like a pure data dump from your camera’s sensor, it’s not even a picture yet, it’s a mass of data which is usually uniquely formatted for every kind of camera so you’ll need special software or filters to read it in conventional software like Photoshop, but as it’s a pure data dump, little is lost (important to note: raw is NOT lossless) and all the processing your camera’s tiny little CPU would normally try and do in record time so you can take another shot, can be done by your beefy laptop/deskop CPU in its own time with no corners cut.  You also get maximum flexibility over the final image, colour balance is an issue of the past, as you can change it on the fly as if you were STILL THERE, basically if that shot really matters to you, you’ll want it in RAW.

JPEG on the other hand is what most of us are used to, a picture, spat out onto the memory card, plain and simple, but the colour balance is fixed and changing it ranges from trivial to impossible, there is a slight (very slight on modern cameras, see picture) loss of quality vs RAW and you’ll often hear people online swear blind that JPEG is the plague that causes cameracancer or something.

Clearly RAW is superior though, right?

Now take a look at file sizes, your average JPEG, depending on noise, light, subject matter and how many megapixels your camera has, will be, say.. 2MB? 4MB? 6?

RAW? 20MB-40MB.

Per shot.

Now ‘course memory cards are cheap, but a factor many overlook, is buffer size and card write speed.  Your camera can take a number of shots in fast internal memory, and one by one write them to the relatively slower memory card, as long as they’re getting written to the card as fast as you’re taking them you can keep going.. In JPEG mode, I can take roughly 30 photos in a row, at 3.5fps before that buffer/output balance runs out of steam.  In RAW? I can take two photos in quick succession, the third a second behind, after that much slower. So about 2.5 photos really.

While the maths doesn’t appear to add up there, remember that the JPEGs are essentially small chunks and can be written to card and cleared from memory quicker to make space for another, RAWs take up huge chunks and won’t free space until they’re all fully written.  RAW+JPEG is another option but it suffers the writing problem even worse!

Also, processing RAWs can be a serious pain in the ass, every photo needs individual attention to get it out of RAW and into a viewable JPEG for other people to see. If you only take a few photos and you want them to be their best, RAW all the way or RAW+JPEG so fewer post-processing headaches but the RAWs are there if you need them, however if you’re like me and you take THOUSANDS, JPEG looks like the much nicer option.

Especially if you’re taking action shots, you need high-speed photo taking, or you take my lead of TAKE A MILLION PHOTOS, ALL THE TIME, SOME WILL COME OUT WELL, then JPEG is king every day.  On the other hand, many professional industries should you ever take that route, may demand RAWs only.

An optimal compromise I go with, is to shoot JPEG by default, and RAW+JPEG during special shoots or times when I know I want the shot just right.

Basically don’t let anyone tell you one is ALWAYS better than the other, go with what suits your style.

Right, this is FAR TOO HUGE, Imma split this up.

Link to part 2 –>

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