Somewhat of a mixed bag here. Overall the sizes of buildings are accurate and off-nadir is being accounted for, but there's definitely some room for improvement. For example a few footprints should be more complex than rectangles and the SE footprints have been moved to include parts of paths (which are a similar colour to the walls). Consider the highways in imagery and how people are moving and accessing areas. The more complex footprints can help map users identify which building they're looking at.

Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
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#REVIEWED_BAD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170898572

You made good use of a secondary imagery source. Just remember to align to the primary source, GPS traces, or existing data depending on the context. The footprint here looks accurate. It could be slightly wider but that's a minor point. It also looks like you were accounting for the roof overhang which is good. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
---
#REVIEWED_GOOD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170898450

You mapped a valid footprint, with an accurate shape, that has been appropriately squared and moved in the direction of its base to account for off-nadir imagery. A clear improvement. Thank you very much for taking my feedback onboard.

A couple of small points of refinement; The footprint could have been a touch smaller to account for the roof overhanging the walls, and the footprint could have been moved slightly more SW becasue it appears to not be positioned quite at the base. In this case the vegetation at the SW corner of this building obscures a portion of the building and its shadow. I made the modifications and uploaded it here so you can visualise it https://osmcha.org/changesets/170903420

Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
---
#REVIEWED_GOOD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170898300

Oh and take care when mapping with off-nadir imagery and the base of a building is obscured. You may need to reference another imagery source, or estimate the position by moving several footprints simultaneously. I hope this helps.

Hi Rabina, the footprints you mapped here all represent buildings and are appropriately squared, however many of them could be more accurate for one reason or another.

It looks like you do not understand how to account for off-nadir imagery i.e. imagery taken at an angle, when mapping. Consider the Tower of Pisa, when mapping footprints from imagery like this the roof can be used to obtain the building's shape, then it should be moved to the base of the building so that they are accurately positioned. In this case the Southern and Western walls of buildings can be seen and the shadows are cast North so you can sometimes see where the shadow originates at the base of the Western corners of buildings. Sometimes you included the wall in the size of the footprints leading to them being oversized. This [video about mapping dense urban areas](https://youtu.be/JAPiGntG6fs) has more information and a guide.

I think you generally map building footpritns oversized.

When mapping buildings, please trace the shape accurately. Accurate building footpritns aid population estimates and prevent issues like data overlaps. Zoom in so that you can see the outline of the building and mark the corners carefully. Exclude shadows and yards when tracing the footprint. Keep in mind that you are looking at the roofs of buildings, but mapping their footprints. Depending on how the scene is lit, pitched roofs may have light and dark sections that belong to one building. Generally pitched roofs overhang the walls of a building, so a footprint slightly smaller than the roof is accurate. You can scale selected features in ID with shift+(-/+), or JOSM with ctrl.+alt+Lclick & drag. Take care to make contributions that others can build upon.

You mapped some more complex buildings as simple rectangles. Do you know how to use the extrude tool or draw complex buildings in JOSM?

Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/

Welcome to OSM and thank you for your contribution!

You spotted buildings in the imagery but some of the footprints you mapped are inaccurate. Every footprint should represent only one building. Please complete the ID editor tutorial if you haven't already.

When mapping buildings, please trace the shape accurately. Accurate building footpritns aid population estimates and prevent issues like data overlaps. Zoom in so that you can see the outline of the building and mark the corners carefully. Exclude shadows and yards when tracing the footprint. Keep in mind that you are looking at the roofs of buildings, but mapping their footprints. Depending on how the scene is lit, pitched roofs may have light and dark sections that belong to one building. Generally pitched roofs overhang the walls of a building, so a footprint slightly smaller than the roof is accurate. You can scale selected features in ID with shift+(-/+), or JOSM with ctrl.+alt+Lclick & drag. Take care to make contributions that others can build upon.

Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/

Welcome to OSM and thank you for your contribution! The footprints you mapped here represent buildings and have been appropriately squared, however they are generally slightly oversized.

When mapping buildings, please trace the shape accurately. Accurate building footpritns aid population estimates and prevent issues like data overlaps. Zoom in so that you can see the outline of the building and mark the corners carefully. Exclude shadows and yards when tracing the footprint. Keep in mind that you are looking at the roofs of buildings, but mapping their footprints. Depending on how the scene is lit, pitched roofs may have light and dark sections that belong to one building. Generally pitched roofs overhang the walls of a building, so a footprint slightly smaller than the roof is accurate. You can scale selected features in ID with shift+(-/+), or JOSM with ctrl.+alt+Lclick & drag. Take care to make contributions that others can build upon.

The footprint I flagged enveloes multiple buildigns. Each footprint should represent one building. Use shadows, colours and plots to discriminate between adjacent buildings. Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
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#REVIEWED_BAD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170701237

These appear to only be walls. Look at the shadow cast by the feature on the East. Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
---
#REVIEWED_BAD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170701251

Welcome to OSM! You spotted buildings in imagery but the footprints you mapped could be more accurate.

When mapping buildings, please trace the shape accurately. Accurate building footpritns aid population estimates and prevent issues like data overlaps. Zoom in so that you can see the outline of the building and mark the corners carefully. Exclude shadows and yards when tracing the footprint. Keep in mind that you are looking at the roofs of buildings, but mapping their footprints. Depending on how the scene is lit, pitched roofs may have light and dark sections that belong to one building. Generally pitched roofs overhang the walls of a building, so a footprint slightly smaller than the roof is accurate. You can scale selected features in ID with shift+(-/+), or JOSM with ctrl.+alt+Lclick & drag. Take care to make contributions that others can build upon.

After mapping buildings, please remember to square their corners. Most buildings have square corners because that's easy to build. Unless the building is clearly a different shape then it's best to assume that the corners should be squared. In the iD Editor, use the `Q` key to square the corners. This [video about squaring features](https://youtu.be/Xs5wX592E1o) has more information and a guide.

See what your mapping currently looks like on the OSM carto standard layer.

Thanks for your contribution.

Did you intend to tag this as a house, or was it a mistake? Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
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#REVIEWED_GOOD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170744217

A valid highway that looks accuraetly tagged. The line should follow the centre of the highway, a few more nodes could have been added on the corners to make it more accurate. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
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#REVIEWED_GOOD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170744384

I think the waestern footprint envelopes two buildings. Each footprint should represent one building. Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
---
#REVIEWED_BAD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170744076

I think that the southern most footprint is mapped as well as the imagery allows.
---
#REVIEWED_GOOD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170744013

Welcome to OSM! you spotted buildings in imagery, tagged and squared them correctly however they are slightly oversized.

When mapping buildings, please trace the shape accurately. Accurate building footpritns aid population estimates and prevent issues like data overlaps. Zoom in so that you can see the outline of the building and mark the corners carefully. Exclude shadows and yards when tracing the footprint. Keep in mind that you are looking at the roofs of buildings, but mapping their footprints. Depending on how the scene is lit, pitched roofs may have light and dark sections that belong to one building. Generally pitched roofs overhang the walls of a building, so a footprint slightly smaller than the roof is accurate. You can scale selected features in ID with shift+(-/+), or JOSM with ctrl.+alt+Lclick & drag. Take care to make contributions that others can build upon.

Thank you for your contribution.

Some of the footpritns you mapped here are quite accurate, but oversized.

When mapping buildings, please trace the shape accurately. Accurate building footpritns aid population estimates and prevent issues like data overlaps. Zoom in so that you can see the outline of the building and mark the corners carefully. Exclude shadows and yards when tracing the footprint. Keep in mind that you are looking at the roofs of buildings, but mapping their footprints. Depending on how the scene is lit, pitched roofs may have light and dark sections that belong to one building. Generally pitched roofs overhang the walls of a building, so a footprint slightly smaller than the roof is accurate. You can scale selected features in ID with shift+(-/+), or JOSM with ctrl.+alt+Lclick & drag. Take care to make contributions that others can build upon.

Welcome to OSM! You spotted buildings in imagery, but many of the footpritns you mapped here envelope either multiple buildings or entire plots.

Each footprint should represent one building. Use shadows and colours and plots to discriminate between adjacent buildings.

Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
---
#REVIEWED_BAD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170752133

Hi, you spotted a building in the imagery but the footprint you mapped is not as accutrate as the imagery allows becasue it is oversized.

When mapping buildings, please trace the shape accurately. Accurate building footpritns aid population estimates and prevent issues like data overlaps. Zoom in so that you can see the outline of the building and mark the corners carefully. Exclude shadows and yards when tracing the footprint. Keep in mind that you are looking at the roofs of buildings, but mapping their footprints. Depending on how the scene is lit, pitched roofs may have light and dark sections that belong to one building. Generally pitched roofs overhang the walls of a building, so a footprint slightly smaller than the roof is accurate. You can scale selected features in ID with shift+(-/+), or JOSM with ctrl.+alt+Lclick & drag. Take care to make contributions that others can build upon.

Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/

You improved the accuracy of this footprint but it is still inaccurate.

After mapping buildings, please remember to square their corners. Most buildings have square corners because that's easy to build. Unless the building is clearly a different shape then it's best to assume that the corners should be squared. In the iD Editor, use the `Q` key to square the corners. This [video about squaring features](https://youtu.be/Xs5wX592E1o) has more information and a guide.

Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/
---
#REVIEWED_BAD #OSMCHA
Published using OSMCha: https://osmcha.org/changesets/170704813

You spotted buildings in the imagery but the footprints you've mapped are not as accurate as the imagery allows.

When mapping buildings, please trace the shape accurately. Accurate building footpritns aid population estimates and prevent issues like data overlaps. Zoom in so that you can see the outline of the building and mark the corners carefully. Exclude shadows and yards when tracing the footprint. Keep in mind that you are looking at the roofs of buildings, but mapping their footprints. Depending on how the scene is lit, pitched roofs may have light and dark sections that belong to one building. Generally pitched roofs overhang the walls of a building, so a footprint slightly smaller than the roof is accurate. You can scale selected features in ID with shift+(-/+), or JOSM with ctrl.+alt+Lclick & drag. Take care to make contributions that others can build upon.

After mapping buildings, please remember to square their corners. Most buildings have square corners because that's easy to build. Unless the building is clearly a different shape then it's best to assume that the corners should be squared. In the iD Editor, use the `Q` key to square the corners. This [video about squaring features](https://youtu.be/Xs5wX592E1o) has more information and a guide.

Please keep this feedback in mind when contributing in future. Thank you for your contribution. If you want to experience the OSM community or to get timely feedback from other mappers; I recommend that you attend a mapathon. You can find events here https://osmcal.org/