ASD pioneered the science of field spectroscopy over 25 years ago and continues to lead the industry with the world's most trusted field-portable UV/Vis/NIR/SWIR spectroradiometers covering the full solar reflected spectrum.

The ASD FieldSpec 4 line of full-range spectroradiometers delivers the fastest and most accurate spectral field measurements available from any commercial field-portable spectroradiometer. Continued enhancements to core instrument spectrometers and other critical components have dramatically improved overall performance, signal, and integration speeds compared to earlier models.

The ASD FieldSpec 4 spectroradiometer is designed specifically around the challenges researchers face when collecting spectral measurements in the field.

  • Full-range detection capacity (350 nm – 2500 nm) provides uniform Vis/NIR/SWIR data collection over the entire solar spectrum.
  • Faster integration speed allows more measurements in a limited solar collection time window.
  • Graded index InGaAs photodiode SWIR detectors ensure seamless measurements in the 1001 nm – 2500 nm spectral range and provide the smallest available spectral sampling interval (bandwidth) in a field portable device.
  • Single element scanning detectors in the SWIR ensure seamless measurements in the 1001 nm – 2500 nm spectral range. This scanning approach eliminates the uncertainty of missing “dead pixels” and the need to fill the gaps with data interpolation and smoothing as required with instruments using “solid state” array SWIR detectors. Also, the use of single element detectors allows for 2-stage thermoelectric cooling resulting in lower dark noise when compared to the single stage cooling used with array detectors.
  • Superior signal throughput and greatly improved radiometric calibration accuracy over signal-to-noise, and radiometric performance ensure data integrity in suboptimal atmospheric conditions.
  • Long-range wireless increases collection coverage potential from a stationary base of operations and enables collections under poor atmospheric conditions by linking of multiple field spectrometers.
  • A permanent fiber optic cable design provides superior signal throughput over detachable fiber optic cable systems and a ruggedized design reduces the risk of signal loss from broken optical fibers.
  • The customized fully adjustable ergonomic Pro-Pack backpack is designed specifically around the workflow rigors of field research. Durable and lightweight, the Pro-Pack backpack makes field portability a reality with the ASD FieldSpec 4 product line and comes standard with every instrument.

Which ASD FieldSpec spectroradiometer model is best suited for my application?

All ASD FieldSpec spectrometers and spectroradiometers provide 3 nm spectral resolution in the VNIR (350 nm – 1000 nm) range. Four spectral resolution options are available for the SWIR (1001 nm – 2500 nm) range.

The enhanced 6 nm SWIR spectral resolution of the ASD FieldSpec 4 Hi-Res NG spectroradiometer provides both the sampling interval (bandwidth) and the spectral resolution to support accurate calibration and image classification analysis with the next generation high spectral resolution hyperspectral sensors.

With 8 nm SWIR spectral resolution the ASD FieldSpec 4 Hi-Res spectroradiometer is the instrument of choice for geological studies and atmospheric research.

The ASD FieldSpec 4 Standard-Res spectroradiometer, with 10 nm SWIR resolution is perfectly suited for characterizing spectral features with a resolution of 10 nm to 50 nm, which covers the technical requirements of most field researchers. The ASD FieldSpec 4 Standard-Res spectroradiometer has long been the industry’s go-to workhorse instrument for trusted field spectroscopy and the scope of potential applications is broad.

Because of its wide optical slit the ASD FieldSpec 4 Wide–Res spectroradiometer provides the highest signal throughput and offers the best signal to noise performance of any ASD FieldSpec model. These high throughput characteristics also benefit field measurements taken in less than optimal illumination conditions. The 30 nm SWIR resolution of the ASD FieldSpec 4 Wide-Res spectroradiometer makes it an ideal fit for applications such as vegetation analysis and vegetation indices that are characterized by broad spectral features. This instrument is also available at a significantly lower price point than other ASD FieldSpec models, which makes it an attractive option when budgets are tight.

The ASD FieldSpec 4 leaves the factory floor capable of collecting reflectance, transmittance, and absorption measurements.  The FieldSpec instruments can also be calibrated as a spectroradiometer, for precise radiance and irradiance measurements.  A wide variety of accessories are available to provide accurate contact or stand-off spectrum collection for any kind of analysis needs.

Not all research needs are created equal and the spectral reflectance characteristics of different materials can vary greatly. In order to better accommodate this real-world variability, the ASD FieldSpec 4 is available with several spectral resolution options in the SWIR range, as well as the ultra-portable ASD FieldSpec HandHeld 2 and HandHeld 2 Pro VNIR-only models.