Introduction
Below is a list of FAQ's related to the release of SkySat 50 cm spatial resolution
How did SkySat spatial resolution improve?
Through a variety of orbital and ground system improvements, Planet is improving both the SkySat basic and ortho product spatial resolutions. By lowering the SkySat orbits from 500 km to 450 km altitude and various processing improvements, the basic product spatial resolution will now be 65 cm at nadir for super-res assets, and 81 cm at nadir for non super-res assets. The ortho product will now be resampled to 50 cm spatial resolution, subject to improve further in the near future.
Asset Types |
Spatial Resolution |
basic_l1a_panchromatic_dn |
0.81 m |
basic_analytic / _dn |
0.81 m |
basic_panchromatic / _dn |
0.65 m |
ortho_panchromatic / _dn |
0.5 m |
ortho_pansharpened |
0.5 m |
ortho_visual |
0.5 m |
ortho_analytic / _dn |
0.5 m |
How will this impact SkySat Collects?
As a result of decreasing altitude, there will be a slight decrease in the swath width to 5.9 km (~10 percent less than before).
Does file size change?
The Ortho SkySatScene and SkySatCollect asset file sizes will increase by approximately 3.5x with the additional pixels introduced by the improved 50 cm resolution (ie, roughly 2.56x the number of pixels per ortho).
Why are file sizes for ortho products bigger?
With 50 cm resolution, the ortho products will have roughly 2.5x the number of pixels than the previous 80 cm ortho products. Hence the new ortho file sizes increase at roughly the same ratio.
Does this impact analytic asset resolution?
Yes, with the 50 cm release, the SkySat analytic product resolution will be less than 1 m. Hence the ortho asset resolution will be 50 cm, and the basic products will be 81 cm at nadir (native sensor resolution).
Will the SkySat Collect still work with my tools?
There will be no changes to the API interface that impact how you access SkySat imagery.
Will the size of the SkySat Collects be larger since the satellites will be in lower orbit?
The footprint of SkySat Collects will actually be smaller with the swath width dropping to 5.9 km. Imagine you are taking a photograph with your phone; moving closer to an object restricts your field of view, so you back up if you want to get more of a “view.” In our case, we have “stepped” closer to what we are imaging.
What resolution will the 50 cm images display in Planet Explore. Will these be displayed at zoom level 18?
SkySat imagery will continue to be displayed at zoom level 17 in Planet Explorer.
How will this impact SkySat Basemap resolution?
SkySat Basemaps will continue to be produced at zoom level 18. However, customers should expect improved resolvability from each pixel due to the lowered satellites and improved resolution.
Will there be any changes to the file formats?
No, neither the image nor metadata format will change with the improved resolution.
When will 50 cm SkySat data appear in the catalog?
All SkySat orthorectified products will be updated to 50 cm resolution starting June 30, 2020.
How far back in time does Planet have 50 cm SkySat imagery?
Only images collected on or after June 30, 2020 will be resampled to 50 cm ortho products. No archive will be reprocessed to this new resolution.
Will the SkySat archive remain at 72 cm spatial resolution?
Yes, the archive up to June 30, 2020 will retain 72 cm basic product resolution (at nadir), however when customers reactivate archive ortho assets for download, they will be reproduced with 50 cm resolution.
Are there any impacts to latency of delivery of ortho products?
No, SkySat Scene and Collect publication latency will not be impacted by the updated 50 cm resolution.
Are there differences in latency between delivery of basic product and ortho products, given improvements to spatial resolution?
No, the Basic L1A asset is the only asset that publishes through the pipeline early, separate from the remaining Basic and Ortho Scene and Collect products, and it is not impacted by the ortho resolution change. Otherwise the remaining Basic and Ortho products publish at the same time.
How does this impact video product resolution?
Video products utilize L1A frames (without super-resolution) hence the resolution will be 81 cm at nadir.
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