But everyone thank you for turning up
today my name is dr. Robert lenford as you're aware of by now and basically I'm
an archaeologists on a project nearby the tram expansion project which if you
drive it off you know you're acutely aware of the traffic that it's causing
so I'm basically on tea break at the moment so I'm just gonna briefly talk
for about 25 minutes or so and I can answer any questions
basically I'm talking about today the coffee stand and the DSLR in this case
it's a Canon 7d some of you may may be very keen digital photographers and some
aspects of this you may be more familiar with that I do quite a bit of a
geography I'm basically self-taught but I've been doing it intensively for about
five years now and basically I take lots and lots of photos of everything so I'm
coming at this from a from kind of a advanced amateur enthusiast perspective
if you will but I also I was the photographer on the poplar Petri project
in which I photographed the pod refined from the site in Greece where dr. John
Henderson and the department here has been working so it took about thousand
artifacts photos on that on that excavation and and then just naturally
in my job as a commercial archeologist at the moment I do a lot of site
photography so but getting away from field work a bit at the moment basically
I'd like to go through and just say a little bit about what is macro
photography which you may or may not have heard of and basically what the
coffee stand what its advantages are over say it
scanner for example if you if you're photographing documents and macro
photography is basically as I eloquently put in handout is making big photos of
small things so technically if you're taking a macro photograph you are taking
a photograph that is larger of that object in real life so if you take a
photograph of a fly for example and you print it off and the fly is this big and
then you are doing macro photography this this copy stand is capable of
helping with that they can also be used with with different lenses now just to
point out the lens along here at the moment is a 100 millimeter lens it's a
macro lens on the side it has a minimum focusing distance of about 31
centimeters now the other two lenses are what they call standard prime lenses
they're a bit wider angle ones a 50 mil 28 mil the lower the number the wider
the angle of view with these lenses these lenses are called prime lenses
versus zoom lenses zoom lens you might have a range from say 18 to 55
millimeter or something like that so you can you can move in and out without
having to move yourself physically remove the camera to get the desired
composition now this one has a macro function
and it will focus within 31 centimeters kit lenses or standard lenses may
actually have a closer focusing distance but the problem is if you get the lens
too close to what you're trying to take photographs up then you're lighting on
the sides is being blocked and in photography lighting is as critical as
everything if you want to get really good results you need to get your
lighting set up properly so I mean said that to switch back just to the coffee
stand basically a copy stand works in the same way as the tripod does just as
the gentleman here is using for his video camera the advantages of a copy
stand as you can see you can get very precise you can get very precise
vertical motion with it and you can also if you in rare cases if you want to tilt
the camera to get an oblique angle you can do so by making basically micro
adjustments with this hat but the primary advantage here is is that you
get excellent control height wise with the camera now the advantages over a
tripod as you can see if you're taking objects horizontally with a tripod you
would need to shorten two of the legs as I've done the forum projects where I
didn't have a copy stand shortened to the legs and have the third leg
extending way out and it's a big kerfuffle you're trying to get the
camera directly over the object you're trying to photograph and you have to
have a rucksack underneath with some books in it to hold everything it's yeah
so this is a much more professional set up you can look in the phreatic
sometimes and find film enlargers that people
and you can actually take the enlarger bit off because it uses a similar base
and upright as the top east and so you can you can almost make a coffee stand
if you're particularly keen on that the lighting is critical
again with this you have what's called white balance which I'll talk about a
little bit more in a minute but the lights the lights used here
mimic basically sunlight at noon or when the sunlight is in overhead conditions
they would have a different color temperature probably than these
fluorescent bulbs overhead so you've got two different lighting sources so you
need to be aware of where you're lighting these horses are coming from
three actually you've got a third color temperature coming into the window but
it's not very strong today so we don't need to worry too much about that I am
now quickly before I move on to more and camera bits the copy stand has primary
advantages for photographing documents and objects with precision documents in
text especially rare text or fragile text that you can't just plunk down in a
flatbed scanner so have a little ditch eye and keep going back and forth page
after page you obviously can't do that with some documents damage them in a
very short manner Laurens documents that I know there is
well this standard here in particular may be able to fit larger documents but
again if it's a rare manuscript for example it's much much preferable to lay
it flat on a copy stand and use it in photographic that way than trying to
scan an image if it's not a rare manuscript but you want to photograph
many pages it's a lot faster to get this set up it takes a minute to set it up
maybe compared to say a scanner once you get it set up you can use the
tether mode where you can actually control the camera from the computer
that's one of the nice functions about this camera and you can actually get it
set up you almost have someone flip the pages
and as soon as they flip the page you can you can activate the shutter here so
you can go very rapidly that way so that's another advantage of it so many
other advantages again the reason why I. Chose this object instead of
photographing a flat object this was just some some bits that were lying
around so we'll call that our widget for today's purposes the reason why I chose
this is because it's it's a taller object so the problem when you're doing
macro photography what you can run into is a problem with depth of field that
means you might get this bit in focus but then if you want to have this part
in focus as well it may not be because bets down to what's known as your
aperture I mean my little handout there I go and talk about this five different
things that when you use your camera most cameras have green mode or
point-and-shoot if you're using an iPhone even every time you use the
digital camera on an automatic setting it's doing five things for you so you
don't have to think about it so you can just take the photo
the first one is focus its auto focusing the second one is shutter speed the
third is aperture the fourth is ISO and the fifth is white
balance basically autofocus most cameras today are very good with autofocus you
don't have to worry about that too much if you were say photographing this
temperature controller over the wall this is what we would call a little
contrast above that because there's not much for the camera to recognize so you
may have to switch to manual focus to get the proper focus on something like
that obviously a more high contrast situation where we have this brass water
fitting the camera will be able to autofocus quite easily so 99% of time
you can leave the camera on the autofocus you don't have to worry about
that the second one is shutter speed as you
can see in the hand down on second or third page there's the bullet passing
through the shutter speed is the difference between having a blurred
photograph or having a nice crisp photograph and you'll find this if you
take photos it's someone's birthday party in low-light and you get your
photos back and they're all blurry it's because you're moving perhaps or the
people themselves are moving so there's different ways you can correct that one
of the ways you can correct that is by changing the aperture which is inside
the lens that controls the amount of light that reaches the sensor the
aperture also controls your depth of field so it's a trade-off there is a
compromise here because otherwise numerically and higher f-stop say you
might look at an old camera lens in my twenty-two on it more things will be in
focus say if you're taking photograph in this room starting from this point here
to the penguin might be in focus at f-22 but if you dial it down to say F 2.8 You
might only get this bit focus if you're if you're photographing that way so
everything's a bit of a trade-off so if you're using deeper apertures that have
a deeper depth of field and you need to increase the shutter speed
correspondingly and it's if everyone does have a handout along you may
already know this and it's um it's it's outlined in in some detail there but one
of the advantages here and if you switch to green mode the camera is going to
make a decision about what aperture you want most of the time that's fine if
you're photographing something flat you don't have to get too caught up in the
technical bits you can set it on green mode and the candidate software and
basically you can start clicking away as long as you have your file settings such
as JPEG or if you want to shoot RAW.
Files basically go to town but saying
this is you'll have to pretend with me here this is an incredibly rare object
and you only have this afternoon to take a few photographs of it before security
comes and takes it back to whatever museum it came from so you don't want to
use green mode in this instance because you may look at your photos the next day
after you've really sat down and you know all the excitement's weren't off
and realize that your aperture didn't allow a sufficient depth of field to
take nice clear detailed photos so what you do if you go to manual mode this is
as the name suggests you full control over all of the camera
settings and this is a perfect environment for using manual mode
because we're a we're shooting an object that doesn't move it'll sit there as
long as we wanted to that allows us to use a very slow shutter speed so we can
set our aperture in our ISO at the highest quality settings to get a really
really good photograph of this object so in this case we're also assisted with
good lighting we know what color is color temperature wise this is about
5,400 degrees Kelvin on these lights you don't have to remember all of this auto
white balance on cameras these days are quite good and since we have a known
color temperature we can always go back and photo editing and change the color
cast if we think it's same not quite as red as it should be or not quite as
yellow so we've got auto focus and auto white balance we don't have to worry too
much about it it's really good these days however to get our depth of field
and if we want to get all of this in InFocus F night it's in spikes Empire well you
won't be able to see it very well I have this set on a very very high
f-stop it's f 29 at the moment f 32 which is actually the maximum for this
lens and we're not done is everything's on manual setting the ISO goes back to
the film days and it's what what your film speed is basically now in digital
that translates to basically image quality if you've taken a photo in
low-light it'll be very grainy the image all will start to break down and
deteriorate that's because your camera in in auto mode is saying oh there's no
light here this is awful so we're going to use very high ISO say ISO 6400 and
you get the image and it looks really awful some people like it for artistic
purposes so they like the nice grainy image but we want really good detailed
images from say publication or maybe even gallery enlargement for an exhibit
at a museum so we want to shoot the lowest ISO possible in this instance
most cameras these days is over 100 is the best set because we're in control
were shooting a non moving object with controlled lighting the camera is held
Rocksteady thanks to the copy stand we're completely in the driver's seat
and we can use a slower shutter speed as it takes to get a really good photo so
to get the depth of field you'll have to do some practice shots and just find out
what the minimum depth of field is that will get everything in focus you really
don't want to just go to the deepest depth of field aperture and and use that
straight away because you will lose a little
detail due to a process called diffraction which I won't really go into
that so basically you want to take some test shots and what I did before
everyone came in just very briefly I. Took I took two photographs of are
priceless widgets and the first one I. Took at what they called wide open
that's f 2.8 And basically you can see the 15 on the end of the camera actually
the the maker's mark or what have you the brand the size of this fitting is is
in focus but you can see how quickly the focus goes away you've got everything's blurred in the
background so all of this is out of focus but you've got a nice sharp focus
on the actual end of the object now at the other end of the aperture spectrum
I've gone and in turn the aperture stuff tip right the way down at 32 so you can
see in comparison how all of this is in focus including this object now because
it's a really good camera and good lens combo we don't have to worry too much
about diffraction because it's very unlikely you're going to be printing
this image off and say a1 I mean how many times do you really print a
photograph that egg one although this image you could come close to doing that
he wanted to so you've got your depth of field and because you've got the copy
stand and as I mentioned you're in control of everything you can set the
object and set the camera settings to the desired settings you want to get the
photograph you want now one thing I need to point out is on
the page with the little this is actually from the canon 7d it shows the
little print extreme drought of the top LCD monitors on the camera what that is
it's a light meter and anyone that's that's done very much photography manual
photography will be familiar with it your older film cameras and it didn't
have a built-in light meter image the David Bailey documentary where his
assistant is holding the little meter out there they're testing the available
light so they know what shutter speeds and what apertures they can get away
with digital cameras these days have light meters built in and so if I go and
change the aperture as I'm doing now I'm going from a really on aperture really
high I've stopped down to say something more normal f/8 I then look at my light
meter because there's a lot more life coming through the lens now because I
opened the aperture I'll just wake it up here okay so now I need to go in
decrease I'm sorry increase my shutter speed because otherwise too much lights
going to come in and what will have a will have a very overexposed image what
I'll do here is I've got it all wrong I. Don't know what I'm doing I press the
shutter yeah that's that's what you called
overexposed image and it looks like a nuclear flash went off in the room so
what you do it's very easy you increase the shutter speed to decrease the amount
of light that reaches the digital sensor and you do that until we get so we find
it is a bit difficult doing the upside down but it only takes a second or two
there this is off the scale so instead of a four second exposure really what we
want is one tenth of a second so basically you just rotate the wheel here
that controls the shutter speed in manual mode until you until you're right
on zero as so now we're back in normal range I go and take another photo
breathing deep sigh of relief because now that's coming out that's at f/8 and
you can see that's halfway in between these maximum and minimum I was talking
about earlier this is actually a bit of a difficult object to photograph because
it does have such a depth of field say I.
Have this set on maximum aperture and it
still is in focus all the way I can alleviate that by moving the camera
further away from the object so I can raise it up and what that does the
further away the camera is from an object the deeper your depth of field is
if you're shooting up very close even at maximum aperture
you might have only a very little bit in focus so this is another reason why it
gives you a lot more control and also by moving that I've maintained my
perspective that I have the previous photo so if I'm taking photos of
different objects I can I can maintain that control throughout the day
consistency the other two lenses are not macro lenses but then again it depends
what you're photographing and macro really only means that the camera has a
closer than normal focusing distance a 100 millimeter lens is getting into
telephoto range that people might use for sports or for wildlife things like
that you can take photos of things across the room a bit closer so to have
a minimum foking focusing distance of 31 centimeters with this lens is quite good
as the macro designation for that one this one is your 50 millimeter what they
call your standard prime and this has a very shallow depth of field if you want
it's f 1.4 It's good for sports and low-light things like that if you do
have an object and you just want to get the very edge of it in focus and give it
a nice artistic effect in the background a nice blur so it's not distracting it
draws your eye in onto just a little bit you want to have in focus and this lens
is about as good as you can get for that it's 50 millimetres so it does give you
a little bit wider angle of view than the 100 and then also is the 28
millimeter Canon lens that if you have say photographing roughly
a a3 sized document you would probably want to switch to the 28 millimeter lens
for that just to get everything in focus and 99% of this is practice it doesn't
take too long but once you get everything set up and take it to a few
test shots of what you're photographing then you'll quickly be able to dial in
the settings and manages quite quite easy to buy to work with once you've
briefly familiarize yourself with it I. Don't even really use panic I've got a
Pentax but I'm thinking about selling it and getting the canons but these days
it's really difficult to get along it's hard to buy a bad digital camera my
camera actually doesn't have the tether feature which is very very good that's
one of the main advantages of this camera besides it it's excellent image
quality is the fact that will combine what the resources here at the digital
humanities center you can you can shoot tethered photos with it and get results
instantly it's tempting just to shoot with a digital and look at the little
screen on the back and say yeah that's a good photo and then you download them
that afternoon and realize that somebody bumped the table or or you have one
little setting off and then the object that you wanted to photograph is back in
the library so yeah it's definitely - I'll stop
there before I run out of breath and I'm like I said this is just a brief
introduction please load the resources on the Internet
but buyer beware when you look at photography blogs and things like that
make sure it's fairly reputable source but by and large the basics of
photography are pretty much the same across the board whether it's film or
digital and then macro photography there's entire websites dedicated to
macro photography if if you want to get very closed off objects if you're
shooting lithics for example say you have a nice flint blade and you want to
get a really good photograph of the edge of it you can move in that's probably
about as close as I can get with that you can move in quite quite closely I
don't need to know what this is because I have it manual say you can get
some obviously I didn't set that up and even look at my composition or just
fired away they you can see with that lens you can get some really really good
it's almost like a microscope so it's a lot of potential there diffusers as in Oh for flash photography
or tour continues lighting I guess you didn't talk about too much is
controlling your light source because you may find that this lightning as it
is is I think good point actually it's too bright it's too harsh and say you're
not getting the desired effect be one with the object you're photographing but
diffuser basically soften it's like a lampshade almost a lampshade is is
effectively a diffuser because instead of sitting in your chair by the
television looking at a light bulb on the table next to you a lampshade acts
as a diffuser and it softens that light and helps reduce shadows same same
effect in photography I almost gather that these holes on the
side of this are probably for some type of diffuser if you've seen photographers
with a it's almost like a bit of white cottony material that just goes over the
the actual bulb just to kind of cut down on par shadows and glare without really
reducing your available light so you can they have light tents out which are just
little pop-up literally a little tense if you're doing item photography that
you can set this inside of a small light tent and keep your light source here and
in almost because it's it's pretty good here but you can see a little bit of a
shadow around this if you want to completely eliminate
shadows then yeah you can use them you can use the diffuser which it almost be
I've heard of people using coffee filters on the spot with the pop-up
flash on their phone their camera I get so yeah you can you can use a diffuser
to break up shadows and if anyone thinks of anything else or has any photo
related questions just drop me an email if I don't know I've got some friends
that probably do so yeah.
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