Questions tagged [reflectance]
Reflectance is the ratio of incident flux and reflected flux from a surface
24 questions with no upvoted or accepted answers
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Negative reflectance values after topographic corrections (cosine correction and modified Minnaert correction)
I am trying to manually correct the surface reflectance values of some Landsat 7 and 8 images. I'm using Minnaert modified method, which uses the cosine correction as one of its inputs (see below the ...
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Viewing Angle Effect On Spectral Reflectance Sentinel-2
I am new to remote sensing and would like resources and literature explaining the effect of viewing angle on spectral reflectance for satellites. I have read the study by Moriya et al translated to ...
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PlanetScope NDWI calculations
I am trying to calculate NDWI for a PlanetScope image scene. I currently have 2 products: one is the "3B_AnalyticMS_SR.tif" and the other is the "3B_AnalyticMS.tif" product. I ...
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Calculating Reflectance from Parrot Sequoia DN
I am dealing with the images of a Parrot Sequoia. I could not pre-process the images in Pix4d because I took single shots in different parts (so there are not overlapping images).. for me it is ...
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When to rescale reflectance data to calculate vegetation indices
I'm attempting to calculate a number of vegetation indices using hyperspectral AVIRIS data in ENVI. Some of these indices are normalized, such as NDVI, whereas others are not, such as the Transformed ...
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eCognition - prevent rounding of raster values?
I have a WorldView2 image, which I would like to segment and classify in eCognition. The image has been pre-processed to Top of the Atmosphere Reflectance, therefore hasvalues between 0-1.
The ...
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What is the difference between surface reflectance and top of atmosphere (TOA) reflectance?
I was told that during winter it is better to use TOA because SR is not good for winter. But I didn't find any files describing it. Can anyone explain the difference of these two and why they perform ...
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Reflectance median extraction on GEE on field values
I want to extract reflectance values of points for field measurment at different dates. I want to get the median reflectance value for each band for 1 pixel around the point to look for the link with ...
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Classifying Object Based on Mean IR Values
While Developing rule sets using e-Cognition for object classification for say; Landsat 7 images what are the threshold conditions to classify water, building, agriculture land & bare soil ...
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Do I need to convert OLI bands DN values to reflectance and TIRS bands DN values to radiance?
I know that this a very trivial question. I downloaded some Landsat 8 images from the USGS website that have the following format (I deleted the processing date):
...
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Does single tile, single date of Sentinel-2 data require BRDF?
I have a single tile of Sentinel-2 Level-2A data from a single date of acquisition.
Does this require bidirectional reflectance distribution function (BRDF), or are the angles consistent enough during ...
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Implementing BRDF in R
I use UAS to survey vegetation at subcentimeter resolution for my research and have found that bidirectional reflectance (BR) is a huge issue that impacts the reliability of estimates across ...
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Calculation of TOA radiance from Sentinel-2 1C product reflectance
I was trying to convert the Sentinel-2 1C product to radiance and came across two links first once says
radiance = ((pixelValueBandX * cos(incidenceAngle) * solarIrradianceBandX) / (pi * d2)) / ...
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view zenith angle of MODIS surface reflectance product and Landsat 8
I have a MODIS daily surface reflectance product (MYD09GA) which I'd like to validate Landsat 8 image with. I want to obtain pixels that only fall within the view zenith angle of Landsat 8 ( 0 - 7.5). ...
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GOCI Radiance to Reflectance
How can I convert a GOCI satellite image from Radiance to Reflectance?
I have been searching through the internet, but most of them are related to other satellites. I try to calculate the reflectance ...
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Converting Digital Number (DN) to reflectance in order to analyze NDVI
I'm working with a mapir nir + red camera meaning that its blue band captures nir light and its red captures red normally. I understand that NDVI is calculated using reflectance values.
How do I ...
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Why Skysat analytic surface reflectance products have wierd reflectance in shadows?
I have a skysat analytic_SR image. I did not get any .json file related to atmospheric correction parameters as they say. I can only get the Planet notes on planetscope for surface reflectance (see ...
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Normalized Difference Turbidity Index (NDTI) wrong
I'm trying to retrieve a turbidity indicator from a Landsat 8 using NDTI :
NDTI=(Red-Green)/(Red+Green).
The problem is the result is not consistent with the reality.
Here is a RGB visualization where ...
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Low reflectance values
I use DJI P4 multispectral. Here is the command I gave in opendronemap software.
–dem-resolution 1.5 --orthophoto-resolution 1.5
–orthophoto-png --dsm
–radiometric-calibration camera
–texturing-skip-...
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Convert Landsat 9 Surface Reflectance product DN to surface reflectance values
I downloaded the Landsat 9 L2 imagery from Earth Explorer for the purpose of calculating NDVI. However, when opened in ArcMap 10, the pixel values are in the range of 7000 to 45000. I understand that ...
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LANDSAT-7 strange strip on SWIR bands (B5 and B7)
I was exploring Landsat 7 data on SentinelHub and came across with this strange strip in the SWIR band B7 (also B5):
By placing a pin in this strip and exploring the stats, I found that there is no ...
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How to Correct Landsat 8 Imagery with TOA Reflectance >1 and <0?
I recently downloaded Landsat 8 T1 imagery and have ran into some difficulties during pre-processing. I applied the TOA reflectance and sun elevation corrections to Bands 2,3,4,5,6 using ArcGIS's ...
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Set multiple values to nodata - Erdas Imagine 2015
I am having trouble with the data ranges in the Landsat 8 surface reflectance product which I downloaded from USGS. The Lansat 8 surface reflectance handbook says the valid range is 0 - 10,000 range ...
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Calculate reflectance for UAV images
I have high resolution images captured by a drone using a , they are RBG and NIR images. My question is how can I calculate the reflectance for the images, the values are currently in digital numbers (...
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