Duplicate maps?


I’m doing a map (of what I supposed to be Puerto Rico). Found a big cruise ship at a dock on the western side of the island in the before picture; then 2 of what appear to be naval vessels in the after picture.

But when I come back to the same area a few minutes later (I reopened my browser) the after image is different. AND…all my tags have disappeared!

Which, of course makes me wonder what is the point in tagging the zillions of damaged buildings, only to come back and find a new “after” photo, and all the tags have vanished?

Is something amiss, or am I doing something wrong?

Here’s the two after pictures.



Hi @Colleen3, I don’t think you are doing anything wrong. Had the same experience on the Dominica-map (cruise ship in the before picture and 2 navy vessels in the after picture there, too :confused:).
Did all the tiles on the map, reopened the map and found a much clearer image of the same map, yet all of my tags were gone (tag counter reset to 0, though consensus score remained as before).


When we were new, we were told the DG computer sees ''everything".

We place a tag - recorded.
X-out a tag - recorded.
X-out and drop a new tag–recorded.
Last view of what we had done before ending a browser session-- recorded.
Leave a browser window open and return hours later to close it-- the work remains recorded.

As far as old-new images, DG Staff is constantly loading in new images. It’s supposed to look seamless, but eagle eyes, like yours, might notice when something changes.

The images come into DG from the satellite as long strips. After a lot of other steps, they “seam” those strips together. So any “duplicate” would have to be a whole strip, according to my understanding.

I’m sure Mel will take a look when she gets in to work.

Tomnod Mod


Hm, saw it happen right before my eyes, now.

Was working on a H. Maria map when I suddenly had to go afk for a while.
When I came back, I saw the map as before - only the tag count was zero and the consensus score way lower than before.
The map reloaded several times automatically, with numbers in both the tag count and consensus score changing with every reload.
In the end, everything went back to normal. :face_with_raised_eyebrow:

I suppose (as @cageycat already pointed out) it has something to do with maps being changed as we work on them - and also with automatic browser refreshs. I’m using Chrome 61.0.3163.100 (64-Bit), btw.


Just a quick look at those two… the urls are distinctly different after 1mg… I’d have to say they are probably different mapsets (strips)… One guess is that they were trying to use a prominent land mark for an alignment point… for overlapping strips. Just a guess but I have noticed ‘common’ landmarks in the Tampa area stips in IRMA.

That said they have re worked images before during the seals.


So I’m not hallucinating! Some of these areas looked so familiar. I think I’ve dropped the same pink dots on the same area three times now.

That doesn’t seem right somehow, does it?


Hello all (@Colleen3, @Doug4, @E-Bear and more…)

Sorry for the slow reply on this. I just double-checked our database to make sure nothing was truly duplicated, and it’s not. What it is is that we have many overlapping strips of Dominica. This can be helpful since they all contain some unique information and different levels of cloud-cover, etc. Here’s screenshot of them all together:

Thanks as always for your work!


@Mel_Nod Thank you for always listening/reading and coming back to us and explaining! (part 1) :bouquet: