DigitalGlobe Premium image disappears on higher zoom levels

[sommerluk]

On higher zoom levels, the DigitalGlobe Premium image disappears on some places in the world. However, in iD at the very same place and the very same zoom level, it works fine.

Example place:
​https://www.openstreetmap.org/#map=19/5.36464/-4.08342

Screenshot:

[sommerluk]

screenshot2.png

[stoecker]

Adding following?

<no-tile-header name="Etag" value="8b83dfdcb2d6a24404982e6563a57f37" />

curl -s -D /dev/stderr https://b.tiles.mapbox.com/v4/digitalglobe.316c9a2e/19/256200/254318.png?access_token=pk.eyJ1IjoiZGlnaXRhbGdsb2JlIiwiYSI6ImNqZGFrZ2c2dzFlMWgyd2x0ZHdmMDB6NzYifQ.9Pl3XOO82ArX94fHV289Pg >/dev/null
HTTP/1.1 200 OK
Content-Type: image/png
Content-Length: 116
Connection: keep-alive
Date: Mon, 11 Jun 2018 14:31:18 GMT
X-Powered-By: Express
Access-Control-Allow-Origin: *
Access-Control-Allow-Methods: GET
Timing-Allow-Origin: *
X-Rate-Limit-Limit: 500000
X-Rate-Limit-Interval: 60
X-Rate-Limit-Reset: 1528727537
Last-Modified: Wed, 25 Apr 2018 17:03:44 GMT
ETag: "8b83dfdcb2d6a24404982e6563a57f37"
Cache-Control: max-age=43200,s-maxage=300
Age: 71
X-Cache: Hit from cloudfront
Via: 1.1 1b1536679e81d123b6aca645be2c5b38.cloudfront.net (CloudFront)
X-Amz-Cf-Id: XZCyk0q1CQQ17I7RnEB-Y-0x4QcoI9GohvullSfnc1Uj_Ej86l5nKg==

[Klumbumbus]

I get a different etag value on every blank tile. So we can use no-tile-checksum instead or would that create different checksums too?

[stoecker]

Replying to Klumbumbus:

I get a different etag value on every blank tile. So we can use no-tile-checksum instead or would that create different checksums too?

In a sensible setup not ;-)

[Klumbumbus]

https://josm.openstreetmap.de/wiki/Maps/Worldwide?action=diff&version=28

Works fine for me.

[Klumbumbus]

(DigitalGlobe Standard Imagery is not affected in this area.)

[sommerluk]

Wow, really fast fix.

Thanks a lot!