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KRISTEN: So our next keynote
speaker is Alex Lorman.

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He is an engineer,
but he has also

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been a professional
photographer.

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And he's going to tell you
what's inside the camera,

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and all the physics behind
it, and some cool things

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cool he's done with
his own cameras.

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So I'm going to
turn it off to Alex.

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Thank you.

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ALEX LORMAN: I promise to bore
you all to death with physics.

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It will be great, I promise.

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So like Kristen mentioned, I
currently work as an engineer.

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I build robotic boats right
now, which is all kinds of fun.

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But I used to build cameras and
take pictures in a former life.

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It's OK, you guys can all
have two careers, too.

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This is what I do.

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I play with sunken ships,
and now I build them.

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It's great.

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It's good times.

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So also for cameras, helicopters
are really useful if you ever

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want to take cool pictures.

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You should go out and
ask your parents for one.

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So this is actually a camera
I built. And that shot--

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the picture on the left--
and before you all say,

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no, you didn't possibly
shoot that picture-- I did,

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and I can show you
the raw feed from it.

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So it's actually a really
old style of camera

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that used to use film.

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How many of you actually
loaded a film camera.

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Awesome.

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Wow.

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That's actually more than
I would have expected.

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So film is the thing,
we'll get into that

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in a couple of slides.

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This was a digital
film hybrid camera.

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So actually the whole
front unit is a film camera

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and it had a platen
glass, which is what you

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used to use to focus the image.

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So before auto-focus
and before fixed focus,

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you actually had to focus
a picture, which involved

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moving pieces of glass around.

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It was super fun.

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And then the thing at the
rear takes a picture of that.

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So it's a really weird set
up, but it also worked,

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and I made it in my basement.

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So you guys can, too.

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Honestly, it's kind of fun to
go to a camera store, or eBay,

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or Amazon, or wherever, and pick
up old used large format camera

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gear.

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And you can do some
fun stuff with it.

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So this did shoot the
image on the left.

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You see it has a really sort
of odd, dreamy quality to it.

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That was in 2008.

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But it can do some
interesting stuff.

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Most of the Secret Service
will think you have a bomb.

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But that's OK.

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So I've built some
other cameras as well.

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You can build time
lapse cameras.

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This is taking apart go pros
and soldering things onto them

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so that microcontrollers--
similar to the Raspberry

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Pi's-- actually, a lot simpler
than the Raspberry Pi's-- could

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control them and take
a picture every--

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I think this was taking a
picture every half an hour,

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something like that.

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So it actually turned the
GoPro on, take a picture,

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and then turn it off again.

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And you guys are actually
building something much more

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sophisticated than that,
so if you guys can all

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do your stuff today,
you're way ahead

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of where I was a
couple years ago.

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It'll be great.

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So that was also solar powered.

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That was fun.

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That was-- why is my
clicker not working?

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There we go.

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So this shot this.

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It will give you a
minute of time lapse.

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That stayed on the top of
a mountain on a project

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I was working on for-- it stayed
up there for like six or eight

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weeks or something.

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I only give you a minute of it.

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It worked out pretty well.

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It was a fun little project.

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Time lapses are cool when
they actually show something.

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In this case, they're not
actually showing very much.

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So there's one or two cool shots
where you get a nice sunrise.

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There we go.

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Isn't that pretty?

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All right, we won't bore you
with any further details.

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So, cameras and how
they've developed.

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I'm sure there are
further notes on this,

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and this is not an exhaustive
history of cameras,

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so don't quote me on any of it.

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In fact, I might
even be making it up.

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I probably am.

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Apparently in 1839,
photographs were

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on paper that probably had
something to do with chemicals

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that reacted to light.

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I'm just guessing.

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But in 1861 they seem to
have gotten it in color.

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Now the thing with both
color, digital cameras,

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and film cameras,
is suddenly you

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need to capture three
different sets of light.

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And that's much more key
with digital cameras--

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and you'll see that-- you
need to capture red, green,

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and blue to make color.

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So then apparently in 1884
they made photographic film.

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They seemed to have had a pretty
good run of that for about

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the next 125 years, 150 years.

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And in 1936 SLRs.

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We'll get into exactly what
SLRs do, and how, and why,

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in just a second.

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That's OK.

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Instant photography.

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Has anyone actually
shot a Polaroid camera,

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where you've got like a little
thing that you have to shake?

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One.

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Cool.

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OK.

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Polaroid used to be
a lot more popular.

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Remember I was talking about
large format cameras before?

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You used to check how they
shot by shooting a Polaroid,

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and then waiting for
the Polaroid of develop,

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and then putting the proper
large format film-- which

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was about this big-- into it.

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So your subjects couldn't
really be going anywhere fast.

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So instant photography
was a thing.

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A little bit before my time,
but it definitely was a thing.

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I've heard about it.

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Auto-focus, we'll get
into auto-focus as well.

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People used to actually have to
manually focus their cameras.

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They had all kinds
of cool things called

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split screens, where
you could-- the image

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would suddenly snap into
focus when you had it right.

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Those were fun.

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You can actually get them for
modern cameras if you want.

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Kodak digital camera.

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So they basically took a--
I think it was an Icon F5--

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and just stripped
the entire thing out

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and put electronics in it.

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They were horribly,
staggeringly expensive, slow,

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and didn't work all that well.

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And really the only people
who used them were newspaper

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photographers because they
needed to get their images out

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as fast as possible.

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They were also about-- the first
ones were like one megapixel,

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maybe not even that.

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They were horrible.

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And that continued for a while,
until 1998 with modern DSLRs.

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Modern DSLRs are really
amazing, and what

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you can get for a couple
of hundred dollars

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is unbelievable.

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So, a 2012 is the
gigapixel camera.

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Apparently-- I'm told--
that is a camera that

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has like 92 lenses that
all shoot at the same time

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and creates a gigapixel image.

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If any of you can tell me
what a gigapixel image is,

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that would be great.

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Because I don't know.

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But I can tell you about DSLRs.

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So-- even have a few here.

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This looks pretty
familiar to everyone?

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Cool.

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Great.

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Ahead of the curve so far.

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This bit, too?

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Lenses?

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Great.

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Let's see if they'll
actually a couple together.

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So, yes?

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Still with me so far?

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And the make clicking noises?

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Fabulous.

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So in this wonderful
diagram, which

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I stole from the internet,
the light path goes in

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and we get lens elements.

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So if you see
through lenses, they

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have bits of glass in them.

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We'll get into much more
about how they work.

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And I'm probably making
half of that up, anyway.

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It might just be black
magic coming through.

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It's fine.

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It's not a problem.

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The aperture.

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So I'll pass around a
manual lens for you,

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and you can see what
the aperture is.

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Who can actually-- oh, come on.

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Lord.

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Who can actually tell
me what an aperture is?

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Anybody?

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Yes, please fire away.

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AUDIENCE: [INAUDIBLE] small
hole that lets light in.

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ALEX LORMAN: Yes.

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That is an accurate summary.

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So-- here, I'll
pass this around.

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The aperture ring
is on the front.

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You hear it click.

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Look through the lens,
you'll see it change.

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Please pass it around.

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Just don't lose it.

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Awesome.

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So she's exactly right.

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The aperture controls how
much light is coming through.

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You say, why on
earth would you want

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less light to come through?

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Can anybody tell me?

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Please, the back.

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AUDIENCE: [INAUDIBLE] picture
doesn't get overexposed.

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ALEX LORMAN: Good.

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Why wouldn't I just want an
obscenely fast shutter speed

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instead?

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It would freeze everything
nice and you could get

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exactly the right freeze frame.

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Anybody else?

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It is-- you're right, you
have a correct answer, though.

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Please.

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AUDIENCE: [INAUDIBLE]

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00:08:12,609 --> 00:08:13,650
ALEX LORMAN: That's true.

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The other one is depth of field.

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So if I'm shooting
with that wide open--

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00:08:18,249 --> 00:08:20,790
and you can sort of see it when
you look through the camera--

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you get a really
shallow focus point.

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And that's great if you're
shooting romantic portraits.

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But if you're not,
you can actually

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00:08:27,800 --> 00:08:30,930
stop it down-- make it
smaller-- and your focus

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00:08:30,930 --> 00:08:32,152
area will increase.

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So suddenly I'll get the
first three rows of you guys

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in focus instead of just one.

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So apertures are
really important.

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Then it comes in, and
bounces up, and then

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bounces around five
times, and out.

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Anybody have a reason why
bounces around five times?

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00:08:46,360 --> 00:08:50,060
Why don't I just put a mirror
right there and call it a day?

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Great.

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00:08:50,560 --> 00:08:51,990
I had to look this one up, too.

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So it bounces around five
times because otherwise it

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would be upside down.

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And who wants to look
through an image upside down?

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00:08:58,540 --> 00:09:00,582
Personally I don't, but
a lot of old view cameras

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00:09:00,582 --> 00:09:02,998
you do have to look at the
image upside down, because they

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00:09:02,998 --> 00:09:04,710
don't have any optics
to flip it over.

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00:09:04,710 --> 00:09:08,230
It's really easy when you have a
developed film to just do that.

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00:09:08,230 --> 00:09:10,160
But you have to actually
focus and compose

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00:09:10,160 --> 00:09:11,590
the camera upside down.

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00:09:11,590 --> 00:09:14,880
These were challenges I learned
when I was building cameras.

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So the sensor and the shutter
are two different things.

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00:09:18,760 --> 00:09:20,910
So you will notice that
the light is not actually

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00:09:20,910 --> 00:09:23,220
going to the sensor or
the shutter right now.

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00:09:23,220 --> 00:09:24,570
We'll get into this in a minute.

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Anyway, that whole
shebang flips up

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00:09:27,770 --> 00:09:29,600
and allows light to
get to the imager,

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and then flips down,
in all the time it

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takes you to press the button.

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It seems complicated,
and honestly

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it really is complicated.

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00:09:37,710 --> 00:09:39,870
There are many simpler
ways of doing this.

256
00:09:39,870 --> 00:09:42,037
And the cameras you're
about to build are simpler.

257
00:09:42,037 --> 00:09:44,620
And thank god, they don't have
all these moving parts to them.

258
00:09:44,620 --> 00:09:46,190
It's great.

259
00:09:46,190 --> 00:09:50,080
So we go into parts of
the camera a little bit.

260
00:09:50,080 --> 00:09:51,119
We've got a lens.

261
00:09:51,119 --> 00:09:52,160
We talked about shutters.

262
00:09:52,160 --> 00:09:53,300
We'll get into
shutters in a second,

263
00:09:53,300 --> 00:09:54,850
they're actually kind of fun.

264
00:09:54,850 --> 00:09:58,260
Flashes, batteries,
sensors, LCDs.

265
00:09:58,260 --> 00:10:01,010
This looks pretty familiar
to everyone, right?

266
00:10:01,010 --> 00:10:02,400
Great.

267
00:10:02,400 --> 00:10:03,840
Lenses.

268
00:10:03,840 --> 00:10:05,570
This is fun, right?

269
00:10:05,570 --> 00:10:07,761
Come on, we're having
fun, aren't we?

270
00:10:07,761 --> 00:10:08,260
Excellent.

271
00:10:08,260 --> 00:10:09,640
Good.

272
00:10:09,640 --> 00:10:10,458
So lenses.

273
00:10:13,270 --> 00:10:13,960
Here's a lens.

274
00:10:13,960 --> 00:10:14,740
We can pass it around.

275
00:10:14,740 --> 00:10:15,250
Don't drop it.

276
00:10:15,250 --> 00:10:16,920
It's already been
dropped about five times.

277
00:10:16,920 --> 00:10:17,670
Don't do it again.

278
00:10:17,670 --> 00:10:20,340
It will be unhappy.

279
00:10:20,340 --> 00:10:24,760
So we have wide angles
and long lenses, right?

280
00:10:24,760 --> 00:10:26,530
Anybody have any idea
why the lenses have

281
00:10:26,530 --> 00:10:29,730
different sizes in the front?

282
00:10:29,730 --> 00:10:30,763
Please.

283
00:10:30,763 --> 00:10:32,655
AUDIENCE: So you can
see more-- [INAUDIBLE]

284
00:10:37,870 --> 00:10:38,777
ALEX LORMAN: No, no.

285
00:10:38,777 --> 00:10:39,860
I see what you're getting.

286
00:10:39,860 --> 00:10:41,102
And the answer is, sort of.

287
00:10:41,102 --> 00:10:42,310
I don't mean to call you out.

288
00:10:42,310 --> 00:10:43,580
But, it's sort of.

289
00:10:43,580 --> 00:10:46,630
So this over here
is an 8 to 15 lens.

290
00:10:46,630 --> 00:10:48,950
Who can tell me what
a focal length is?

291
00:10:48,950 --> 00:10:49,450
Nobody.

292
00:10:49,450 --> 00:10:49,710
Great.

293
00:10:49,710 --> 00:10:50,230
Fantastic.

294
00:10:50,230 --> 00:10:50,801
That's fine.

295
00:10:50,801 --> 00:10:51,300
Don't worry.

296
00:10:51,300 --> 00:10:53,890
So focal length is
how wide the lens is.

297
00:10:53,890 --> 00:10:57,590
8 millimeters is really,
really, really, shockingly wide.

298
00:10:57,590 --> 00:10:58,810
Like, it's like this.

299
00:10:58,810 --> 00:11:00,420
In fact, that's a fisheye lens.

300
00:11:00,420 --> 00:11:03,100
It's a really nice little
lens, but it's hugely wide.

301
00:11:03,100 --> 00:11:05,630
And over there we have a
300 millimeter lens, which

302
00:11:05,630 --> 00:11:08,130
is about this long,
costs more than all

303
00:11:08,130 --> 00:11:12,630
of your first cars will, and
shoots-- focuses somewhere over

304
00:11:12,630 --> 00:11:15,440
there to begin with, and you
can't really focus any closer.

305
00:11:15,440 --> 00:11:16,940
But they're really
beautiful lenses

306
00:11:16,940 --> 00:11:18,960
for doing certain things.

307
00:11:18,960 --> 00:11:23,290
So we've covered what focal
length is between 8 and 200.

308
00:11:23,290 --> 00:11:25,630
But the aperture is a big thing.

309
00:11:25,630 --> 00:11:29,717
We talked about the aperture
and the iris in the lens.

310
00:11:29,717 --> 00:11:31,550
You will not be able
to see through the lens

311
00:11:31,550 --> 00:11:32,716
even if you look through it.

312
00:11:32,716 --> 00:11:35,510
I promise you you'll
never get it to focus.

313
00:11:35,510 --> 00:11:37,510
But it's a fun try.

314
00:11:37,510 --> 00:11:42,100
So the big expensive lenses
let a ton of light in,

315
00:11:42,100 --> 00:11:44,620
and that's why they're
big and expensive.

316
00:11:44,620 --> 00:11:45,160
Seriously.

317
00:11:45,160 --> 00:11:47,030
No, that is exactly why.

318
00:11:47,030 --> 00:11:49,490
In terms of optics as well,
you'll notice none of these

319
00:11:49,490 --> 00:11:53,980
are 8 to 200 because you
can't actually produce

320
00:11:53,980 --> 00:11:55,350
good optics that do that.

321
00:11:55,350 --> 00:11:58,150
It is not within the
realm of physics.

322
00:11:58,150 --> 00:12:00,510
People try, and they
make really bad lenses

323
00:12:00,510 --> 00:12:02,330
that do like 8 to 200.

324
00:12:02,330 --> 00:12:06,090
And they're about this big,
and they're not very good.

325
00:12:06,090 --> 00:12:07,456
That's OK.

326
00:12:07,456 --> 00:12:08,830
Your lenses on
the Raspberry Pi's

327
00:12:08,830 --> 00:12:11,530
are moderns of marvel
engineering-- of-- you

328
00:12:11,530 --> 00:12:12,810
know what I meant.

329
00:12:12,810 --> 00:12:13,310
All right.

330
00:12:13,310 --> 00:12:13,980
So here's a fun bit.

331
00:12:13,980 --> 00:12:14,604
Here's a video.

332
00:12:14,604 --> 00:12:17,640
So shutters-- we talked about
shutters briefly, right?

333
00:12:17,640 --> 00:12:20,130
They expose the imager
to light, and then stop,

334
00:12:20,130 --> 00:12:22,590
and they do it in a
very precise timing.

335
00:12:22,590 --> 00:12:24,850
So same thing as film.

336
00:12:24,850 --> 00:12:27,649
So we're watching this at
10,000 frames a second.

337
00:12:27,649 --> 00:12:29,190
And I think someone
is coming to talk

338
00:12:29,190 --> 00:12:30,648
about high speed
cameras, which are

339
00:12:30,648 --> 00:12:32,710
their own really awesome thing.

340
00:12:32,710 --> 00:12:36,760
So we'll watch this again with
more narration, if that's OK.

341
00:12:36,760 --> 00:12:40,560
If you all can tolerate
30 seconds again.

342
00:12:40,560 --> 00:12:43,394
So we talked about the
mirror flipping up.

343
00:12:43,394 --> 00:12:44,310
There goes the mirror.

344
00:12:44,310 --> 00:12:46,570
This is in one exposure.

345
00:12:46,570 --> 00:12:49,970
Now we see these are all
different exposure times,

346
00:12:49,970 --> 00:12:52,170
so they let different
amounts of light in.

347
00:12:52,170 --> 00:12:53,040
And you'll see that.

348
00:12:53,040 --> 00:12:57,080
Watch the size of the
shutter as it rolls by.

349
00:12:57,080 --> 00:12:57,580
There we go.

350
00:12:57,580 --> 00:13:00,260
See one's much bigger,
one's much smaller.

351
00:13:00,260 --> 00:13:02,860
Lets much more light in
versus much less light in.

352
00:13:02,860 --> 00:13:05,050
And now the mirror
is coming back down.

353
00:13:05,050 --> 00:13:08,390
So you see how phenomenally
fast this processes is.

354
00:13:08,390 --> 00:13:12,440
And modern DLSRs can do this
on the order of 10 to 14 times

355
00:13:12,440 --> 00:13:13,620
a second.

356
00:13:13,620 --> 00:13:16,530
Which is really cool, and
sounds like a machine gun.

357
00:13:16,530 --> 00:13:18,330
That's OK.

358
00:13:18,330 --> 00:13:21,480
So the imagers.

359
00:13:21,480 --> 00:13:23,130
These are the imagers.

360
00:13:23,130 --> 00:13:24,390
Yeah, they're we go.

361
00:13:24,390 --> 00:13:24,890
See?

362
00:13:24,890 --> 00:13:27,850
That's roughly 8 to
10 frames a second.

363
00:13:27,850 --> 00:13:29,480
They go quickly.

364
00:13:29,480 --> 00:13:33,260
So in film, 10 frames
a second would last you

365
00:13:33,260 --> 00:13:34,840
about three seconds.

366
00:13:34,840 --> 00:13:39,380
And they actually invented
big, high capacity basically

367
00:13:39,380 --> 00:13:42,120
magazines for stuff like
sports photographers,

368
00:13:42,120 --> 00:13:44,170
that had 250 shots in them.

369
00:13:44,170 --> 00:13:46,860
And you'd have a roll of
film that was about this big.

370
00:13:46,860 --> 00:13:48,450
And they were horrible.

371
00:13:48,450 --> 00:13:52,490
And some cameras got
away without the mirror

372
00:13:52,490 --> 00:13:56,050
snapping up and down by having
something called a split

373
00:13:56,050 --> 00:13:58,852
mirror, and let some light
through and some light up

374
00:13:58,852 --> 00:13:59,560
at the same time.

375
00:13:59,560 --> 00:14:02,530
So you basically got a
bad image in both places,

376
00:14:02,530 --> 00:14:05,015
but you didn't have to flip
the mirror up every time,

377
00:14:05,015 --> 00:14:07,140
so you could just shoot
the film through like there

378
00:14:07,140 --> 00:14:08,610
was no tomorrow.

379
00:14:08,610 --> 00:14:10,050
Sports photography is hard.

380
00:14:10,050 --> 00:14:11,550
If you want to start
in photography,

381
00:14:11,550 --> 00:14:14,320
sports is probably not
the place because you

382
00:14:14,320 --> 00:14:16,710
need thousands and thousands
of dollars of equipment.

383
00:14:16,710 --> 00:14:18,130
Don't worry about it.

384
00:14:18,130 --> 00:14:19,680
This is a CCD.

385
00:14:19,680 --> 00:14:23,271
I am not the right person to
tell you exactly how they work.

386
00:14:23,271 --> 00:14:25,770
I'm sure one of the other people
that does this for a living

387
00:14:25,770 --> 00:14:29,610
can, and can tell you how to
make them in your basement.

388
00:14:29,610 --> 00:14:31,130
Which would be really cool.

389
00:14:31,130 --> 00:14:35,110
But essentially they convert
light photons to electricity.

390
00:14:35,110 --> 00:14:37,670
And then the computers
in the cameras

391
00:14:37,670 --> 00:14:40,490
convert that to a picture, and
then write it to an SD card,

392
00:14:40,490 --> 00:14:41,382
and we go from there.

393
00:14:41,382 --> 00:14:43,590
So the cameras you're going
to building, like I said,

394
00:14:43,590 --> 00:14:46,920
are marvels of
modern engineering.

395
00:14:46,920 --> 00:14:50,830
All of that-- lens,
shutter, focus-- all of that

396
00:14:50,830 --> 00:14:53,780
is built into something
that is absolutely tiny

397
00:14:53,780 --> 00:14:56,550
and costs like $25.

398
00:14:56,550 --> 00:14:57,830
It's amazing.

399
00:14:57,830 --> 00:14:59,800
And actually, all of
the image processing

400
00:14:59,800 --> 00:15:01,870
is on-board the camera as well.

401
00:15:01,870 --> 00:15:03,730
And it sends it over
a communication bus

402
00:15:03,730 --> 00:15:07,400
called SPI, which is a
standardized communication bus.

403
00:15:07,400 --> 00:15:11,550
So it's actually incredible what
these little cameras can do.

404
00:15:11,550 --> 00:15:14,900
And no, they're never
going to shoot as nicely

405
00:15:14,900 --> 00:15:17,710
as the giant piece of
glass that's flying around.

406
00:15:17,710 --> 00:15:20,310
But they're also on a chip.

407
00:15:20,310 --> 00:15:23,880
How many of you use your
iPhones over a different camera?

408
00:15:23,880 --> 00:15:26,830
Like a smartphone instead
of an actual camera?

409
00:15:26,830 --> 00:15:27,340
Most of you?

410
00:15:27,340 --> 00:15:27,881
Don't be shy.

411
00:15:27,881 --> 00:15:29,939
It's OK to admit it.

412
00:15:29,939 --> 00:15:30,480
There you go.

413
00:15:30,480 --> 00:15:31,370
See?

414
00:15:31,370 --> 00:15:34,660
So the marvels of
cell phone technology

415
00:15:34,660 --> 00:15:35,660
have brought us to this.

416
00:15:35,660 --> 00:15:38,480
And that's why you can
buy it for $25 or $30,

417
00:15:38,480 --> 00:15:39,870
which is still
pretty incredible.

418
00:15:39,870 --> 00:15:45,329
And the volume of production
for that is unbelievable.

419
00:15:45,329 --> 00:15:47,370
There is a fun trick with
that lens, if you want.

420
00:15:47,370 --> 00:15:49,020
If you can hold a
smartphone behind it,

421
00:15:49,020 --> 00:15:50,436
you might be able
to get the image

422
00:15:50,436 --> 00:15:52,049
to focus on the
smartphone camera

423
00:15:52,049 --> 00:15:54,590
and shoot some kind of weirdly
distorted, and probably upside

424
00:15:54,590 --> 00:15:56,300
down, picture.

425
00:15:56,300 --> 00:15:59,240
It will probably be upside down
because the light is probably

426
00:15:59,240 --> 00:16:01,780
crossing as it goes
through to focus.

427
00:16:01,780 --> 00:16:02,280
Maybe.

428
00:16:02,280 --> 00:16:05,456
You can do it with a set of
binoculars, too, actually.

429
00:16:05,456 --> 00:16:07,100
AUDIENCE: [INAUDIBLE]

430
00:16:07,100 --> 00:16:08,160
ALEX LORMAN: Nope.

431
00:16:08,160 --> 00:16:10,632
Everyone's welcome to try it.

432
00:16:10,632 --> 00:16:13,215
In fact I'll pass around another
lens and we can do that, too.

433
00:16:16,860 --> 00:16:20,455
Again, they're all heavy because
they are really fast lenses.

434
00:16:22,790 --> 00:16:23,290
Here.

435
00:16:23,290 --> 00:16:24,456
That's another fun activity.

436
00:16:24,456 --> 00:16:25,110
Go for it.

437
00:16:25,110 --> 00:16:26,484
Just don't drop
that one, please.

438
00:16:26,484 --> 00:16:27,894
I really like that one.

439
00:16:27,894 --> 00:16:29,310
If I have to pick
one lens, that's

440
00:16:29,310 --> 00:16:30,351
the one I go around with.

441
00:16:32,780 --> 00:16:33,390
All right.

442
00:16:33,390 --> 00:16:33,890
OK.

443
00:16:33,890 --> 00:16:35,790
And please, you can
play with smartphones

444
00:16:35,790 --> 00:16:39,520
and try to get a picture
if you desperately desire.

445
00:16:39,520 --> 00:16:41,310
Like I said, the
Raspberry Pi cameras

446
00:16:41,310 --> 00:16:44,374
are really stunningly amazing,
and you can do really fun stuff

447
00:16:44,374 --> 00:16:46,540
with lots and lots of them
because they're so cheap.

448
00:16:46,540 --> 00:16:48,390
And I think someone's
going to show you

449
00:16:48,390 --> 00:16:51,640
how to do photogrammetric
scanning with them,

450
00:16:51,640 --> 00:16:54,030
which is really cool.

451
00:16:54,030 --> 00:16:56,060
But that concludes cameras.

452
00:16:56,060 --> 00:16:58,160
Who has questions
about any part of that?

453
00:16:58,160 --> 00:17:00,960
Because we really breezed over
like several hundred years

454
00:17:00,960 --> 00:17:03,305
of development and
science in 20 minutes.

455
00:17:05,950 --> 00:17:09,940
Who can explain how a
shutter works, roughly?

456
00:17:09,940 --> 00:17:11,670
I clearly didn't
do a very good job.

457
00:17:11,670 --> 00:17:14,150
Oh, no-- please-- save me.

458
00:17:14,150 --> 00:17:14,650
No?

459
00:17:14,650 --> 00:17:16,650
All right.

460
00:17:16,650 --> 00:17:19,698
What does a shutter do?

461
00:17:19,698 --> 00:17:21,099
AUDIENCE: [INAUDIBLE]

462
00:17:21,099 --> 00:17:22,335
ALEX LORMAN: Please.

463
00:17:22,335 --> 00:17:23,460
AUDIENCE: It lets light in.

464
00:17:23,460 --> 00:17:24,210
ALEX LORMAN: Yeah.

465
00:17:24,210 --> 00:17:25,930
Exactly.

466
00:17:25,930 --> 00:17:26,540
Perfect.

467
00:17:26,540 --> 00:17:27,240
Detector.

468
00:17:27,240 --> 00:17:29,180
It's 10 points for
the scientific words.

469
00:17:29,180 --> 00:17:30,131
Very good.

470
00:17:30,131 --> 00:17:30,630
All right.

471
00:17:30,630 --> 00:17:31,130
Excellent.

472
00:17:31,130 --> 00:17:33,830
And apertures, again?

473
00:17:33,830 --> 00:17:36,022
AUDIENCE: [INAUDIBLE]

474
00:17:36,022 --> 00:17:36,730
ALEX LORMAN: Yep.

475
00:17:36,730 --> 00:17:37,540
Perfect.

476
00:17:37,540 --> 00:17:38,200
All right.

477
00:17:38,200 --> 00:17:39,266
Fabulous.

478
00:17:39,266 --> 00:17:40,640
I think I'm going
to hand it back

479
00:17:40,640 --> 00:17:42,348
to whoever else is
running the show here,

480
00:17:42,348 --> 00:17:44,200
because it's clearly not me.

481
00:17:44,200 --> 00:17:45,630
And hopefully you
have enjoyed it.

482
00:17:45,630 --> 00:17:47,190
And hopefully I get
all of the lenses

483
00:17:47,190 --> 00:17:48,670
that I passed out
back at the end,

484
00:17:48,670 --> 00:17:52,210
otherwise I'm going to
sit and cry in the corner.

485
00:17:52,210 --> 00:17:54,210
I promise you,
there will be tears.

486
00:17:54,210 --> 00:17:56,210
KRISTEN: Let's give him
a big round of applause.

487
00:17:56,210 --> 00:17:57,087
[APPLAUSE]

488
00:17:57,087 --> 00:17:58,170
ALEX LORMAN: Thanks, guys.

489
00:18:02,100 --> 00:18:04,800
If anyone does have
questions, please fire away.

490
00:18:04,800 --> 00:18:05,540
No?

491
00:18:05,540 --> 00:18:06,830
Yes, please.

492
00:18:06,830 --> 00:18:08,955
AUDIENCE: Why is that camera
called a Raspberry Pi?

493
00:18:08,955 --> 00:18:11,121
ALEX LORMAN: That is a
question for the Raspberry Pi

494
00:18:11,121 --> 00:18:12,930
foundation, who's
based in the UK.

495
00:18:12,930 --> 00:18:16,480
And I honestly don't know.

496
00:18:16,480 --> 00:18:19,740
No, but seriously, the
Raspberry Pi Foundation

497
00:18:19,740 --> 00:18:21,820
is a nonprofit that
makes Raspberry Pi,

498
00:18:21,820 --> 00:18:24,110
and they started making
the Raspberry Pi camera.

499
00:18:24,110 --> 00:18:26,990
And that's what they do.

500
00:18:26,990 --> 00:18:30,480
I don't have a better answer
than that, unfortunately.

501
00:18:30,480 --> 00:18:32,490
Anybody else?

502
00:18:32,490 --> 00:18:32,990
No?

503
00:18:32,990 --> 00:18:35,790
If you really wanted
to get into like boards

504
00:18:35,790 --> 00:18:37,930
produced by nonprofits,
literally the BBC--

505
00:18:37,930 --> 00:18:40,480
like the news
organization-- just came out

506
00:18:40,480 --> 00:18:43,470
with a tiny little
ARM based Linux board,

507
00:18:43,470 --> 00:18:46,257
which they're giving away to
all school children in the UK.

508
00:18:46,257 --> 00:18:48,590
Which is pretty cool, actually,
when you think about it.

509
00:18:48,590 --> 00:18:50,006
Better yet, they've
included tools

510
00:18:50,006 --> 00:18:52,950
to actually do things with it.

511
00:18:52,950 --> 00:18:53,460
All right.

512
00:18:53,460 --> 00:18:54,043
Thank you all.

513
00:18:54,043 --> 00:18:55,290
Appreciate it.

514
00:18:55,290 --> 00:18:56,840
[APPLAUSE]