FAQs

Here are our answers to some frequently asked questions from users.

I never received an account invitation email. What should I do?

Please check your spam inbox. If you still don't see the invitation email, reach out to [email protected] for assistance.

I received my temporary password, but I see an error when I try to connect to the API. What's happening?

You may encounter a 500 Internal Server Error if you attempt to connect to the API without first resetting your temporary password.

To reset your temporary password, please follow the instructions here.

Can I browse the catalog even if I haven't ordered any data?

Yes! Please email [email protected] requesting a demo account.

You can also check out our Open Data Program, which you won't need an account to access.

What is STAC?

STAC stands for "SpatioTemporal Asset Catalog". It's a standardized framework for indexing, cataloging, and describing geospatial data. It makes Hydrosat data easier to work with, especially if you're integrating it with data from other sources.

What do the different assets in a STAC item represent?

Each STAC item includes several assets representing the individual data and metadata files associated with the scene. Items from different collections have different assets, as defined below and on our Product Details page.

vz-viri-l1a

Asset	Description	File Type
BLUE	Blue band digital number (DN) values	COG
GREEN	Green band DNs	COG
NIR	NIR band DNs	COG
RED	Red band DNs	COG
REDEDGE1	Red edge 1 band DNs	COG
REDEDGE2	Red edge 2 band DNs	COG
REDEDGE3	Red edge 3 band DNs	COG
QUALITY_ASSURANCE	Radiometric saturation mask	COG
PREVIEW	Full-resolution RGB preview image	COG
THUMBNAIL	Low-resolution RGB thumbnail	PNG
METADATA	Ancillary metadata file	JSON

COGs from the vz-viri-l1a collection are provided at the resolution of the VIRI sensor (~30 m).

vz-liri-l1a

Asset	Description	File Type
LWIR1	LWIR 1 band digital number (DN) values	COG
LWIR2	LWIR 2 band DNs	COG
QUALITY_ASSURANCE	Radiometric saturation mask	COG
PREVIEW_LWIR	Full-resolution LWIR preview image	COG
THUMBNAIL	Low-resolution thumbnail	PNG
METADATA	Ancillary metadata file	JSON

COGs from the vz-liri-l1a collection are provided at the resolution of the LIRI sensor (~70 m).

vz-l1b

Asset	Description	File Type
BLUE	Blue band digital number (DN) values	COG
GREEN	Green band DNs	COG
NIR	NIR band DNs	COG
RED	Red band DNs	COG
REDEDGE1	Red edge 1 band DNs	COG
REDEDGE2	Red edge 2 band DNs	COG
REDEDGE3	Red edge 3 band DNs	COG
LWIR1	LWIR 1 band DNs	COG
LWIR2	LWIR 2 band DNs	COG
QUALITY_ASSURANCE	Radiometric saturation mask	COG
CLOUD_MASK	Mask indicating cloud, cloud shadow, and snow or ice	COG
PREVIEW	Full-resolution RGB preview image	COG
PREVIEW_LWIR	Full-resolution LWIR preview image	COG
THUMBNAIL	Low-resolution RGB thumbnail	PNG
METADATA	Ancillary metadata file	JSON

COGs from the vz-l1b collection are provided at 30 m resolution.

vz-l2

Asset	Description	File Type
BLUE_SR	Blue band surface reflectance	COG
GREEN_SR	Green band surface reflectance	COG
NIR_SR	NIR band surface reflectance	COG
RED_SR	Red band surface reflectance	COG
REDEDGE1_SR	Red edge 1 band surface reflectance	COG
REDEDGE2_SR	Red edge 2 band surface reflectance	COG
REDEDGE3_SR	Red edge 3 band surface reflectance	COG
LWIR1_BT	LWIR 1 band brightness temperature	COG
LWIR2_BT	LWIR 2 band brightness temperature	COG
LWIR1_EMIS	LWIR 1 band emissivity	COG
LWIR2_EMIS	LWIR 2 band emissivity	COG
LST	Land surface temperature	COG
LST_UNCERTAINTY	Land surface temperature uncertainty	COG
QUALITY_ASSURANCE	Radiometric saturation mask	COG
CLOUD_MASK	Mask indicating cloud, cloud shadow, and snow or ice	COG
PREVIEW	Full-resolution RGB preview image	COG
PREVIEW_LST	Full-resolution LST preview image	COG
THUMBNAIL	Low-resolution RGB thumbnail	PNG
THUMBNAIL_LST	Low-resolution LST thumbnail	PNG
METADATA	Ancillary metadata file	JSON

COGs from the vz-l2 collection are provided at 30 m resolution.

I only see thumbnail assets for certain scenes. Where's the rest of the data?

You have full access to the scenes you've ordered and thumbnail access to the rest of the catalog.

What do the different values in the cloud mask mean?

The cloud mask encodes information about clear or cloudy conditions present within each pixel.

Specifically, the cloud mask contains bit-packed pixel values; each pixel value is a decimal representation of binary strings, in which each bit represents a different condition.

For simplicity, we recommend using the look-up table below. The table displays common pixel values and their meanings.

Value	Clear	No data	Cloud
0
1
2

If you see a value of 2 in the cloud mask, for example, this would indicate cloudy conditions.

You can also review our how-to guide on using the cloud mask for additional information.

How can I use Hydrosat data with Google Earth Engine?

We recommend using the Google Earth Engine Python API along with the xee extension to smoothly integrate the two data sources.

I want to learn more about Hydrosat's data products. Where can I find more information?

You can find additional details in our product guide. Please reach out to your organization point of contact if you don't already have this document.