hi I'm not let me hard and this is another behind the scenes film for the
short film clips clips as an entry into the my Road real 2015 competition and as
part of that we were asked to make a short behind the scenes making a film
but that was only land to be three minutes long and i wanted to show a bit
more of the process behind how we did some of the shots particularly the sky
replacements and some of the VFX shots and I couldn't fit into the three-minute
making up so I thought I take the time to show you that now
so in this shot this is one of our key shots for the film our character sara is
about to encounter the solar eclipse and when we shot it
it was a little late in the day the sky had gone a bit flat
the lights have gone quite flat and actually the light look fine
the light on her looks great and it sort of suited what we wanted but we wanted
to make the sky a bit more dramatic
it's been interesting watching the behind-the-scenes documentaries for the
reason mad max fury road almost every shot in that has had the sky replaced so
this is a really useful technique and replacing skies can give you so much
more drama in your shot
and if you live in England like I do especially the northeast of England it
cold and it can be cloudy and miserable
ninety percent of the time so I do a lot of sky replacement
so in this shot obviously the camera was on a dolly on a rubber wheel dolly and
obviously was a couple of problems here one of which is the sky is a bit flat
and the other of which is that there is an enormous great light in shot with the
width of the lens and with the shot we could really put that light anywhere
else we knew it was going to be there so we knew that was something we were going
to have to fix in post and so here's the shot in after effects you can see that
we went for an anamorphic aspect ratio of around 23 9 21 and that gave us a
composition size of 2048 by a hundred and fifty eight pixels so the original
shot although shot 69
we made our composition that size and after effect and rendered all our shots
at that side
the first thing to do is track the shot and I did that just using the 2d tracker
and after effects you can see that you just have to pick two points on the
horizon
make sure that you have the switches select for position scale and rotation
and then let after effects to is Magic tracking shot and you did that very well
you then apply that tracking to an object an object is an object in the
scene that you can't see it doesn't do anything else other
really just be a place where information like tracking data can be stored and
other items other things in the shop can be parented are made to match the
movement of that an object and it's a useful way of just basically keeping
everything together
so once we have that knowledge extract into the scene we found our sky and this
is a sky that i found through a google image search online and it's always when
you search for stuff on google you can always see search for items that are
labeled for reuse that aren't copyright control the road Creative Commons
copyright free and i found this wonderful shot a lot of detail my scale
- it's about three and a half thousand pixels wide
perfect for what we needed so once we drop them into after effects with a
little bit of a master's to feather the bottom of it off and position to enter
the shot
I parented to the null object and you can see that it locks perfectly into the
shot
so the next thing to do is to put our actress Rachel teat you play Sarah back
in over the top and also the horizon as well and we do that just by putting
another layer of the original video back over the top and using a luma key just
using the extract effect in after effects with a very very soft luminance
key
lots of feathering on it so you keeping some of the original sky in there and
and it's blending over the top of the new sky that you put in that and once
that's in we have another layer of the original footage again just with a mask
on and I just helped us keep in all the foreground details and fill in any holes
for anything that had got dropped out for instance there's a small bright spot
on the bottom of the skateboard ramp and that was getting cut out by the luma key
so putting that mask in without layer just actually help fill that back in and
also kept the highlight line by the trees meet the sky look much better I
think
and again everything's feathered lots and lots of feathering
and obviously we need to get rid of the light as well the light stand is still
in the light itself as being covered now by the sky but the light stand still
there so we track to another track . just a standard again to the track in
after effects and once we had that we went and found another plate of the same
scene but didn't have the life standard I think this is from actually just a
previous take it from a different angle and the light stand wasn't in the shot
glass we managed to grab a piece of the horizon with the trees and the sky
just take it from that shot cut out the bit that we wanted and an overlay it
onto the top of our new composition here
now we just need our Eclipse rather than wait 16 years for him to come around and
be there at exactly the right time that we make our own
so this is a very very simple composition it's just a solid with a
circular mask and then another circular mask subtracting away from that and then
we put that into the image then of course we had a lens flare using optical
flares from video copilot and the great thing about optical flow is is that it
lets you create custom flares in particular
custom textures and so what I did was I created some custom flyer objects from
images that actually came from a real solar eclipse and there was a solar
eclipse that happened and was visible in the UK in march this year was one of the
inspirations behind making this film and so I went out with my ps4 camera and
very long lens and some gaffer tape and some ND filters because I didn't have
the right adapter to put the ND filters on front of the camera so thank you
gotta tape and I shot some footage and as you can see that footage goes very
distinct lens flares and you can see those little green half moons and orange
half moons that actually came from the lens and i was using and from the actual
solar eclipse and so I took those as images
I put them into optical flares and I made my own custom eclipse lens flare
that's track to a light and the light is track to the null object again
and so it moves perfectly with the scene
finally we did some color correction so added in an orange solid with a mask
heavily feathered not just give a little bit of wants to the sky a little bit
more of a sunset field and then another mask on a black solid which is set to
overlay and that's just creating a bit of shadow from the Eclipse and then
another solid just filling in that little bit of hole in the background
where we replaced the skyline the trees the the difference in like that just
didn't seem to quite much for me
and because we shot on the area mirror shot in log see which is the very very
flat mode that the area cameras have and it gives a very flat image but I wanted
to see what this image look like in rec 709 color space which was where we were
going to end up so I and applied an adjustment layer
I went utility apply color lot and I selected the rec 709 a mirror a lot that
i have and i just put on as an adjustment layer over the top so that i
could see and actually the final rendering what i did was i ten that
adjustment layer into a guide layer so they wouldn't render with the footage
but it's just useful as a guide here in after effects so that i could see how
the final shot was going to look added in some great not too much just said to
a ten percent and overlaid over the top of the image and I just have to blend in
the elements that we got it like the lens flare like the clouds just give
everything a subtle grain and it just helps it all sit together
and finally i added in some stock footage of some custom lens flies
and these came from a company called lens distortions from the legacy pack
it's great stuff i really recommend it if you can get hold of it and not just
gave us a lovely glow as the Eclipse sort of first enters the top of the
screen there and matching with your lens flares I think gives the shot
I really organic look obviously this wasn't the final shot after this we took
it into the davinci resolve we did a color grade so the final shot here has
got a slight color grade on it and there's the final shot
thank you very much for watching I hope that was useful and sky replacement
something I've had to do a lot over the years so I know they were really useful
skill to have a really useful thing to learn in after effect
now if you haven't please take the time to watch eclipse and vote for a city
like it on the road real
thank you very much