#1915 - Sri Lanka Floods: Eastern Kelani River Basin instruction contradiction

classic Classic list List threaded Threaded
3 messages Options
Reply | Threaded
Open this post in threaded view
|

#1915 - Sri Lanka Floods: Eastern Kelani River Basin instruction contradiction

Alan Bragg
​I'm afraid I don't understand the instructions for task #1915.

 "Either use Bing to trace features and then align it with Mapbox or use Mapbox to trace and then align it with Bing imagery.​"

The second half of the above sentence seems to be the exact opposite of the first half.
Can someone please clarify. 


_______________________________________________
HOT mailing list
[hidden email]
https://lists.openstreetmap.org/listinfo/hot
Reply | Threaded
Open this post in threaded view
|

Re: #1915 - Sri Lanka Floods: Eastern Kelani River Basin instruction contradiction

Community Working Group

Hi Alan,

 

Yes, sorry – hard to write this short and sweet.

 

Basically east of Ambulgama both Bing and Mapbox imagery source ‘changes’; in particular the ‘hi-res’ tiles of Mapbox (i.e. beyond zoom level 17) is not available.

 

So, you’ll be able to see the buildings better in Bing. So I’ve been accomplishing tracing by either just leaving Bing as is, trace the buildings, then switch to Mapbox and drag them to line-up, as we’ve still checked and although the offset is ‘less’ between Bing and Mapbox, Mapbox is still in better alignment.

 

Another ‘fancier’ way to do this is check to see if the roads are lined up with the Mapbox imagery, if so, you can adjust the Bing Imagery first, then trace off that and you’ll be all lined up.

 

But Mapbox is also more recent imagery, so there might be new construction.

 

In other words, you really should be using both imagery sources for this area to ‘get the best picture’.

 

=Russ

 

From: Alan Bragg [mailto:[hidden email]]
Sent: Monday, May 23, 2016 7:11 AM
To: [hidden email]
Subject: [HOT] #1915 - Sri Lanka Floods: Eastern Kelani River Basin instruction contradiction

 

I'm afraid I don't understand the instructions for task #1915.

 

 "Either use Bing to trace features and then align it with Mapbox or use Mapbox to trace and then align it with Bing imagery."

 

The second half of the above sentence seems to be the exact opposite of the first half.

Can someone please clarify. 

 


_______________________________________________
HOT mailing list
[hidden email]
https://lists.openstreetmap.org/listinfo/hot
Reply | Threaded
Open this post in threaded view
|

Re: #1915 - Sri Lanka Floods: Eastern Kelani River Basin instruction contradiction

Community Working Group

Nope Alan, you were completely correct; adding back the list in case others were wondering. That was a literal ‘lost in translation’ issue; as we’ve had folks working furiously to get everything translated into the local languages.

 

So, sorry and thanks for pointing things out when they don’t make sense; it’s reworded now, hope it’s clearer (and non-contradictory now).

 

=Russ

 

From: [hidden email] [mailto:[hidden email]] On Behalf Of Alan Bragg
Sent: Monday, May 23, 2016 9:19 AM
To: Russell Deffner
Subject: Re: [HOT] #1915 - Sri Lanka Floods: Eastern Kelani River Basin instruction contradiction

 

Hi Russ,

Thanks, I understood that and that's what I was doing but the second part of the instruction doesn't make sense to me. It you can "use Mapbox to trace and then align it with Bing imagery."

That would be wrong according to your message. There'd be a bunch of buildings traced in Mapbox and then moved to align with Bing.

I must be missing something.

Thanks for the quick response.

Alan

 

 

On Mon, May 23, 2016 at 9:32 AM, Russell Deffner <[hidden email]> wrote:

Hi Alan,

 

Yes, sorry – hard to write this short and sweet.

 

Basically east of Ambulgama both Bing and Mapbox imagery source ‘changes’; in particular the ‘hi-res’ tiles of Mapbox (i.e. beyond zoom level 17) is not available.

 

So, you’ll be able to see the buildings better in Bing. So I’ve been accomplishing tracing by either just leaving Bing as is, trace the buildings, then switch to Mapbox and drag them to line-up, as we’ve still checked and although the offset is ‘less’ between Bing and Mapbox, Mapbox is still in better alignment.

 

Another ‘fancier’ way to do this is check to see if the roads are lined up with the Mapbox imagery, if so, you can adjust the Bing Imagery first, then trace off that and you’ll be all lined up.

 

But Mapbox is also more recent imagery, so there might be new construction.

 

In other words, you really should be using both imagery sources for this area to ‘get the best picture’.

 

=Russ

 

From: Alan Bragg [mailto:[hidden email]]
Sent: Monday, May 23, 2016 7:11 AM
To: [hidden email]
Subject: [HOT] #1915 - Sri Lanka Floods: Eastern Kelani River Basin instruction contradiction

 

I'm afraid I don't understand the instructions for task #1915.

 

 "Either use Bing to trace features and then align it with Mapbox or use Mapbox to trace and then align it with Bing imagery."

 

The second half of the above sentence seems to be the exact opposite of the first half.

Can someone please clarify. 

 

 


_______________________________________________
HOT mailing list
[hidden email]
https://lists.openstreetmap.org/listinfo/hot