Re: [HOT] Task manager description/instructions #591

[Max Bainrot]

Hi Charlotte,

Welcome :)

Also in the comments sometimes people put the offsets, although note I am
not aware of a way to feed iD numerical offsets (I used iD for a day or so
then went to JOSM)

I usually align to the osm features as best as possible as this *should*
result in the most accurate atleast for manual navigable maps

But be careful, the worldview and bing imagery are at different angles (I'm
new to osm hot and osm mapping too and that one bit me on the bottom about
a few days to a week ago). Results in structures having wrong shapes from
misleading shadows, etc

Nb I am new too so if I've made some wrong assumptions please do let me know

73s,
Max - mbainrot
On 03/01/2015 6:41 am, "Blake Girardot"  wrote:

> Hi Charlotte,
>
> In iD:
>
> Click on the Background settings (icon looks like stack of papers).
>
> At the bottom of the slide out panel click the arrow next to "Fix
> Alignment"
>
> Then use the 4 "arrows" that show up to move the background image around
> and get it lined up.
>
> As I said, usually, if Bing is the "reference" you draw a few things
> exactly as show on Bing, then Background to switch back to the custom
> imagery and then "fix alignment" to move the custom imagery to match then
> things you drew over the Bing imagery.
>
> It is hard to find, I had to ask as well for iD.
>
> Cheers,
> Blake
>
> On 1/2/2015 8:24 PM, Charlotte Wolter wrote:
>
>> Blake,
>>
>> How does one change the alignment of imagery with ID? I've been
>> mapping with ID for over a year, and I never heard of that.
>> This is just what Laura is talking about. We need plain and simple
>> guidance.
>> When both the Bing and Worldview imagery were available in Mali, I used
>> only the Bing imagery, because it was clearly superior (no huge pixels),
>> and I
>> moved objects as necessary to align with Bing.
>>
>> Charlotte
>>
>>
>> On 1/2/2015 3:14 PM, Laura Green wrote:
>>
>>> > Might someone be able to clarify the instructions shown on the HOT
>>> page please?
>>> > > I *think* it means (for JOSM users, not sure if it applies to ID):
>>> > > 1) please map roads, streets, buildings, walls, water streams and
>>> canals.
>>> > 2) disregard the automatic imagery that downloads when you
>>> contribute, download Bing imagery instead.
>>> > 3) Bing imagery is now aligned correctly (as of date xxx), so please
>>> realign or redraw vector data to match the Bing imagery.
>>>
>>> This applies to ID and JOSM. The task will load WorldView imagery
>>> for either editor. I think you have the directions basically correct,
>>> but as I read them now my understanding is this:
>>> 1. Start editing a task.
>>> 2. Load the Bing imagery (now 2013 images). (In JOSM do not use the
>>> alignment database plugin settings, they are no long needed for Bing
>>> imagery)
>>> 3. Make sure some buildings and roads are mapped correctly using the Bing
>>> imagery. Move or map some new ones to match Bing.
>>> 4. Then load the WorldView imagery (2014 imagery).
>>> 5. Background align the WorldView imagery to match what you just mapped
>>> in using the Bing imagery if needed.
>>> 6. Carry on mapping using the WorldView imagery after you have aligned
>>> it or checked its alignment.
>>> Discussion: Just make sure you use the Bing imagery as the reference. So
>>> you would not do any background image alignment with the Bing imagery.
>>> If buildings or roads were not well matched to the Bing imagery you could
>>> redraw them to match the Bing imagery. Once you have drawn some buildings
>>> and roads using the Bing imagery, you would then display the WorldView
>>> imagery and do the background image alignment to make the WorldView
>>> imagery match up with what you drew using the Bing imagery if that is
>>> needed.
>>> That process is what it means to use the Bing imagery as the reference
>>> imagery:
>>> You map some with Bing, then align any other imagery to what you
>>> mapped using
>>> the Bing imagery.
>>>
>>> > ...but I may be misinterpreting the description/instructions.
>>> > > I’d like to comment generally about the hot task manager
>>> descriptions/instructions:
>>> > > Unless indicated as "Expert only" at the very beginning of an
>>> activation page, I'm
>>> assuming all activations are for the general public to contribute to?
>>> The "whys and
>>> wherefores" and technical information I feel are often getting in the
>>> way of plain
>>> and simple guidance as to what is required, so people can just get on
>>> with it, and not
>>> have to hunt for the pertinent information.  Plainly worded bullet
>>> points would be ideal.
>>> Any "nice to know" information could be provided below this.
>>>
>>> You are right on each point here. It is a challenge though with many
>>> different people
>>> creating directions for Projects. It is too easy to forget not
>>> everyone knows what
>>> "vector data" is. And there is the issue that not everyone is a native
>>> speaker of the
>>> language the directions might be written in. We are working to create

Re: [HOT] Starting on JOSM

[Max Bainrot]

Hi Andrew,

On 14 Jan 2015 6:28 am, "Andrew Patterson"  wrote:
>
> I am just starting to do some plotting on task #591 - South Sudan Crisis,
Cholera outbreak in Juba, mapping with WorldView-2 - task 38 and would
welcome some checking and the answer to a couple of questions before I do
too much abortive work.  The first question is, I guess, whether this is
the correct forum into which to place this request.

Yup this is the right place a far as I know

>
> In opening Task 38 I had assumed from the instructions that the preset
image would be Worldview-2, but I notice from the offset database to which
it is currently set that the name given is Digital Global - is this one and
the same.
>
> When I first started mapping I used iD editor and bling, which had a very
clear image from which I also digitised some areas that appeared to be
cultivated areas.  Although not asked for, these areas did provide some
explanation for certain tracks.  When I converted to JOSM as loaded, on one
occasion I moved the bling image to co-incide with my plotted items, and
adjusted the placing of these areas.  Are both of these actions valid?

To my understanding of the Sudan Juba task it doesn't say not to, and
agricultural places would suggest a presence of a water source.

As for imagery I also found that iD editor was a bit difficult to get bing
imagery to work, in JOSM you may need to click the eye ball (on the bus ATM
so I can't check to describe the icon)

What I have also found helpful is to use transparency to help align the
bing imagery to the worldview to the OSM data

>
> Finally, the square that I am currently mapping was for the most part
empty, accept in the southern end where a number of tracks and buildings
had been entered at least 12 months ago.  These do not appear to have been
on a particular offset, and are therefore considerably astray with the
offset that I am using.  Am I justified in moving them, particularly in the
light of the instruction information about the update of imagery.
>

If your confident that the astray items are the ones offset not the other
data then I would say its safe to do so. I also look at neighboring tiles
to be sure that your imagery is properly aligned

One thing I forgot to do on the tile I was working on was I forgot to check
for GPS traces as they (particularly in numbers ) are ultimately the golden
source of truth.

Though please note that I am very new to OSM and HOT so your milage on my
advice may vary :)

Cheers
Max
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Re: [HOT] Satellite image quality too low for mapping / not loading

[Max Bainrot]

I am quite new too (having done only 1 quarter tile before for South Sudan
Ebola crisis and a little bit of mapping in my local area) and I can relate
to your frustration, what further compounds things is the countries
cultures, building style, etc can and often are different to that of where
you live/have experienced

What I do when I have a hard time identifying features is zoom in and out,
usually that helps with the low resolution and sometimes the stitching
obscures things on one zoom level but goes away on a different zoom level

Usually you can see a contrast that forms an X or a line in the center
which is the roof capping and that's a pretty good give away

Another one depending on the imagery is shadows, they give you a really
good idea of what a given structure is and how high it is (thus helping you
decide if its a short wall/hedge or a proper fence)

Also try cycling between different imagery and that can help identify
structures due to different times of day captures, etc

When I was helping out with the Sudan Ebola outbreak I found it a lot
easier to cycle between bing and the other imagery (my memory is bad
sorry), one was quite bright but low res the other was higher res but alot
darker with longer shadows, between the two it helped me identify what
looked like small buildings to be vans as well as highlight buildings that
weren't visible in the other imagery

Another thing that helps you learn is in your editor (I use JOSM, not very
beginner friendly but it's worth it IMHO) is to toggle your DATA layer (the
layer all the polygons are on) that'll make it easier to see whats beneath
other peoples work and help you learn what buildings, carports, outdoor
toilets/wells look like on the sat photos/aeriel photographs

After a short time you'll get to know certain ground features (random dirt
clearings, weird bright reflections, etc) that give away that there is a
structure there/nearby and it'll make things easier.

Cheers,
Max
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