Introduction to PLOTS MapKnitter

We're going to start by looking at this image that we gotten from a balloon --
This is actually done by RiverKeeper and the Grassroots Mappers in New York City --
And it's of the New Town Creek at the north of Brooklyn
So here's a map that's already been started
with a couple images placed but
this new image actually gives us a little bit more information about this end of it.
So what we're gonna do is actually click the upload image button
we're going to select that image
and upload
You can see the progress down in the corner
and...
there you go.
It highlights it to start with just so that you see where your new image is.
'Cause sometimes there's a lot of images on the page
So, ah, just to get started
uh... you're already in the distort tool; I'm going to click the rotate tool, and you can see
that the red highlights show up
and just kind of drag this around
This is also the scale tool so I can get it to be neighborhood of
the size I'll want it in
I'll drag this over here
It's not perfect but it's pretty close so I'll try scaling it a
little bit more.
And then what you want to do is click the
image outline button.
And that's actually pretty good fit already: that's probably maybe fifty centimeters,
maybe better?
But to really get a good look we're gonna want to turn off the other images.
Because you really want to be aligning it with uh... your reference image.
Otherwise if you you continued to align against other images
you'll kind of begin drifting.
So what I've done is that I've used the keyword command "o" to just outline all
the other images to that they're kind of out of the way
And unfortunately we can't zoom in anymore here because ironically Google does not
provide imagery that's high enough resolution
So we'll just have to do our best here
You can turn it on and off and see that it's a little bit off
For adjustments like this I like to use the "t" button which actually corresponds
to this image here
or rather this tool, "toggle image transparency"
and then uh...
we're going to try to raise this a little bit
until really kind of snaps, it fits
uh... it worked there for a second
we're beginning to drift out but oh that was it see how that
grating there kinda really clicks
Let's turn off transparency
and it looks like we're doing pretty good
um...
I might bring in this corner a little bit
But you have to remember that the version that you're looking at is
actually a low resolution version
only when run the export
will it actually generate a full resolution
...output.
So here we go.
I'm gonna lock that in place 'cause I'm pretty confident about where it is
I'm going to turn off outlining on these.
There are key commands for most of the tools so you can get better as you go
And you can see actually that compared to this image
which is taken from quite an angle where the building is distorted
the new imagery placed correctly locates that grating and gives us a little bit
more of this pier along this side.
So you repeat this for a number of images you can see that this map has quite a few
leading down to the cement factory here
They're documenting a plume of cement that the company's actually been dumping
So at a certain point you're going to want to actually run an export. You click the
map export button
You have to prove that you're human
Uh... we've had some spammers uh... or spambots come in and actually generate maps...
and then you get these different map products
The Geotiff is the most archival, highest resolution version
but the openlayers viewer is also, you know, an option just for web viewing.
So that's kind of a quick way to get up and running with MapKnitter
There are some more advanced tutorials
on their way and we'll be publishing them on the PublicLaboratory.org website. Thanks!