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Product Details

Learn more about the different data products Hydrosat provides.

Level-1 Imagery

The Level-1A data product is the least processed of the available imagery. It includes processing applied onboard the instrument, such as time delay integration and non-uniformity corrections, as well as co-registration of sensor bands and georegistration. The full swath data is provided to users in image space with no resampling. Level-1A pixel values represent top-of-atmosphere (TOA) radiance [W/m²/sr/μm].

The Level-1B product includes converting the radiance values to TOA reflectance (VIRI) or brightness temperature (LIRI), clipping the VIRI data to the extent of the LIRI swath, generation of a cloud mask, and orthorectification.

L1 Product Granule Size

L1A VIRI: 122 km x 70 km

L1A LIRI: 70 km x 70 km

L1B: Combined 70 km x 70 km

Each STAC item includes several assets representing the individual data and metadata files associated with the scene. Items from different collections contain a different set of assets, as defined below.

L1A VIRI TOA radiance values can be converted to TOA reflectance by applying the per-band LEVEL1_REFLECTANCE_SCALING coefficient in the companion L1A metadata (MTA) file.

L1A LIRI TOA radiance values can be converted to brightness temperature using the following equation:

where K₁ and K₂ are per-band LEVEL1_THERMAL_CONSTANTS from the L1A MTA file, and L represents scaled radiance.

L1B VIRI reflectance data can be converted back to TOA radiance by applying the per-band LEVEL1_RADIANCE_SCALING coefficient in the companion L1B MTA file.

L1B LIRI BT values can be converted back to TOA radiance using the following equation:

where K₁ and K₂ are per-band LEVEL1_BT_TO_RADIANCE_CONSTANTS from the L1B MTA file.

The Level-2 product includes radiometric terrain corrections and conversion to surface reflectance (SR) and land surface temperature (LST).

Level-2 assets include per-band SR and LST COGs (and more).

Changelog

A list of satellite data product updates, including release dates and key features.

May 21, 2026: Footprint Geometry Correction

We've deployed a minor fix to ensure representativeness of STAC item footprint geometries with actual imaged area.

March 31, 2026: Coregistration Improvements

We've refined our mutual information-based coregistration workflow for improved feature matching between the LWIR and VNIR data.

February 24, 2026: Geometric Processing Improvements

We've updated our georeferencing and VNIR band alignment workflows to improve geolocation accuracy and band-to-band registration. This release includes:

An enhanced optical distortion correction to reduce residual along-track offsets
Use of a digital elevation model (DEM) to improve band-to-band registration over complex terrain

February 5, 2026: Level-1 Unit Changes

We've modified the units for our Level-1A and Level-1B data products.

Previously, L1A and L1B imagery assets contained per-band digital number data. To arrive at radiance, the user needed to apply gain and offset coefficients provided in product metadata.

Level-1A Products

L1A imagery assets now natively contain per-band top-of-atmosphere (TOA) radiance values. Gain and offset coefficients are applied as part of Hydrosat's data processing.

January 27, 2026: Thumbnail Colorization Improvements (LWIR)

We've improved the contrast and visual consistency in our L1B and L2 thermal thumbnails and previews. This includes:

Consistent scaling across the full imaging strip rather than within individual scenes.
A switch from the

January 20, 2026: Noise Mitigation

We've implemented a minor correction for noise in the thermal products.

January 14, 2026: Thumbnail Colorization Improvements (RGB)

We've released a color curve approach that improves the visual contrast in our true color thumbnails. This change has no impacts on the underlying data.

December 17, 2025: Updated Cloud Mask

We've released an improved cloud mask, which uses a U-Net convolutional neural network architecture. The new model outperforms our baseline Fmask approach across several key metrics.

Product Details

Learn more about the different data products Hydrosat provides.

Level-1 Imagery

L1 Product Granule Size

L1A VIRI: 122 km x 70 km

L1A LIRI: 70 km x 70 km

L1B: Combined 70 km x 70 km

L1A VIRI TOA radiance values can be converted to TOA reflectance by applying the per-band LEVEL1_REFLECTANCE_SCALING coefficient in the companion L1A metadata (MTA) file.

L1A LIRI TOA radiance values can be converted to brightness temperature using the following equation:

where K₁ and K₂ are per-band LEVEL1_THERMAL_CONSTANTS from the L1A MTA file, and L represents scaled radiance.

L1B VIRI reflectance data can be converted back to TOA radiance by applying the per-band LEVEL1_RADIANCE_SCALING coefficient in the companion L1B MTA file.

L1B LIRI BT values can be converted back to TOA radiance using the following equation:

where K₁ and K₂ are per-band LEVEL1_BT_TO_RADIANCE_CONSTANTS from the L1B MTA file.

The Level-2 product includes radiometric terrain corrections and conversion to surface reflectance (SR) and land surface temperature (LST).

Level-2 assets include per-band SR and LST COGs (and more).

Changelog

A list of satellite data product updates, including release dates and key features.

May 21, 2026: Footprint Geometry Correction

We've deployed a minor fix to ensure representativeness of STAC item footprint geometries with actual imaged area.

March 31, 2026: Coregistration Improvements

We've refined our mutual information-based coregistration workflow for improved feature matching between the LWIR and VNIR data.

February 24, 2026: Geometric Processing Improvements

We've updated our georeferencing and VNIR band alignment workflows to improve geolocation accuracy and band-to-band registration. This release includes:

An enhanced optical distortion correction to reduce residual along-track offsets
Use of a digital elevation model (DEM) to improve band-to-band registration over complex terrain

February 5, 2026: Level-1 Unit Changes

We've modified the units for our Level-1A and Level-1B data products.

Previously, L1A and L1B imagery assets contained per-band digital number data. To arrive at radiance, the user needed to apply gain and offset coefficients provided in product metadata.

Level-1A Products

L1A imagery assets now natively contain per-band top-of-atmosphere (TOA) radiance values. Gain and offset coefficients are applied as part of Hydrosat's data processing.

January 27, 2026: Thumbnail Colorization Improvements (LWIR)

We've improved the contrast and visual consistency in our L1B and L2 thermal thumbnails and previews. This includes:

Consistent scaling across the full imaging strip rather than within individual scenes.
A switch from the

January 20, 2026: Noise Mitigation

We've implemented a minor correction for noise in the thermal products.

January 14, 2026: Thumbnail Colorization Improvements (RGB)

We've released a color curve approach that improves the visual contrast in our true color thumbnails. This change has no impacts on the underlying data.

December 17, 2025: Updated Cloud Mask

We've released an improved cloud mask, which uses a U-Net convolutional neural network architecture. The new model outperforms our baseline Fmask approach across several key metrics.

Product Details

Level-1 Imagery

Changelog

Product Details

Level-1 Imagery

Level-1 Assets

Conversions

Level-1A VIRI

Level-1A LIRI

Level-1B VIRI

Level-1B LIRI

Level-2 Imagery

Level-2 Assets

Changelog

Before The Change

After The Change