1. Reflectance values range between 0 & 1 unless any mistake happens during correction or the image has clouds. 2. In ArcGIS, don't directly use sin(x) or alike functions where x is in degree. Because ArcGIS read these functions values as radians. So always convert the values in radians before inputting it in sin/cos type functions in raster calculator or input only the value of the function doing math elsewhere(like him). Thanks
correct me if im wrong, in the video, you process the Landsat 8 to produce TOA, as far as i know, TOA (top of atmospheric) still includes atmospheric effect on the Landsat, while SR (surface reflectance) excluding atmospheric effect.
So is this atmospheric or radiometric correction? Also, what do I do when I have values like 7953 for high and -420 for low (band 5 LC8)? Please help - a beginner. Thank you all.
Very good dear Usman Buhari, excelent video.We are working with Landsat images on Uruguay, and use this video for atmospheric corrections.We are looking for summer crops on Uruguay, wich are regulated here by us: Ministry livestock Agriculture: the government, people have to creat 1 "soil use plan of conservation " for each agriculture crop plantation.Agonomist Martin Dell'Acqua GIS-MGAP-Uruguay Republic
Excellent! Pls, hv u got any video on LST calculation using raster calculator in arcGIS? I wonder what was the problem, but my output gives me too large value to consider as Celsius whenever I compute that.
This is not atmospheric correction. This is radiometric calibration and conversion to top-of-atmosphere reflectance. Atmospheric attenuation is not taken into account at all.
Hi Sean, could you please give me a literature that has mentioned the methodology of the atmospheric correction, I need it for my thesis. Thank you in advance.
You are welcome Mina, you need to have the Spatial Analyst license then activate the extension. Goto toolboxes and find it under spatial analyst - map algebra. As for Landsat thermal image what exactly do you want? The thermal image is band6 in Landsat TM and band10/11 in Landsat 8.
+Usman Buhari Hi! Thanks for an informative video. I am trying to Convert to Landsat DN value to TOA reflectance using your formula. But the problem is that I did not find any metadata like Band_specificReflectance_band and Reflectance_add_band. But I found radiance_mault_band_7 and radiance_add_band something like that (this metadata is for Landsat 1-3 images). I used this value following your formula and I got the NDVI value range is ok (-1 to +1) but red and NIR reflectance value varies. My question is now is it ok to use radiance_mault_band_7 instead of reflactance_mault_band_7. using ArcGIS 10. If it is not ok? What is the formula to convert Radiance to TOAReflactance.
Thanks for video. Is there really big difference in doing atmospheric correction of rugged terrain from a plug-in named Atcor in Erdas software as compared to the formula as given in video above?
Hi, Thank you for an interesting video. Please can you clarify to me on the procedure for atmospheric correction. The conversion from DN to TOA is that a radiometric or atmospheric correction? If using other software like ENVI for instance which has a radiometric calibration tool and DOS or FLAASH, will your method still be applicable?
Hi Thanks for this tutorial I would like to know if I can use this atmospheric correction method before calculating LST using band 10 Landsat 8 OLI TIRS
+Usman Buhari do you know how to make the corrections for Landsat 7? Thanks María, yo también ando batallando con la corrección con Landsat 7. Supiste como solucionarlo. Por qué miro el manual de usuario de Landsat y no lo entiendo.
I am having issues being able to load in/create the composite.tif image you have with the 3 visible bands. The data I have downloaded does not seem to have that raster. Was that composite.tif image created post download? or have I downloaded the wrong dataset (Level 1 GeoTIFF Data Product)?
Hey sorry for the late reply, what Landsat data are You trying to composite? You can atleast assume if your download was the right one by the size of the zipped folder downloaded. There also just .jpeg files that are in the download option, could they be what you have downloaded? If you downloaded the right files then the individual bands should have a unique naming convention like LN00019059165 this is not an actual name though, just for sample sake.
First i would like thank you for your amazing videos. My question is that as my study area falls under multiple scenes due to large area. The sun elevation is different for different scenes. I want to know how to choose the sun elevation for different scenes as i have to mosiac them first, Then calculate Say NDVI, LST etc...
Sir thank you much for your enormous effort in creating such a platform for GIS learners. Whatever I have learned about remote sensing and GIS, that forms your website and the page. I am very much thankful to you I need your help I am looking for a tutorial on how to drive PM 10and PM 2.5 form Landsat 8 data. It will be a great pleasure for me if you kindly extend your helping hand.
Dear Usman, Thank you for this explanatory video. Could you please answer the following queries? Thanks, 1. I was wondering why you would do atmospheric correction after you had made the composite image. Are we not supposed to do atmospheric correction for all individual bands before making the composite? Or we can do that even after making the composite image? 2. Also, for calculating NDVI do we even need the composite or we can just do atmospheric correction for NIR and Red bands and just calculate NDVI values as you have done? 3. How can we plot the spectral signatures of various objects using this NDVI?
1. You should always do an atmospheric correction before anything (including the composite). 2. Since RED an NIR bands are all you need to estimate NDVI, you can use just them without doing a composite as seen in the video. 3. NDVI is mainly for vegetation analysis.
Thanks Usman. I was trying to do atmospheric correction for landsat 7 data. But I found that this formula would not work there as they haven't provided band specific reflectance values like those in landsat 8 metadata. How can we correct the landsat data for atmospheric effects and sun angle using raster calculater? Please help
annd again sir i have made the composite image........and i have been given with a .dat file which contains the training index values for 7 class .......how can i use that .dat file
Mr. Buhari. I probably made a mistake on calculating NDVI, I appreciate if you can help me with this. Atmospheric correction was ok. However, I run NDVI and raster output presents values ranging between -73,46 and 554,555 (Automatic on IMAGE ANALYSIS) and ranging from -29,32 to 129,2 (Raster Calculator). How do I get it in the correct range (0-1)?
Ahh i see, put the formular in raster calculator like this: float(NIR-RED)/float(NIR+RED). This should work if you did the atmospheric correction well.
Hello, I would like to make atmospheric corrections to all my bands. Can I use the same formula (band spesific reflectance_mult_band x DN values + reflectance_add_band) for all the bands? For example for bands 1-3 as well?
Would you mind telling some of them sir???becoz whatever tutorials i was watching .....each consisting 7 bands.....but i have been given only 4 band of an area.... How can i combine these 4 bands to show heat visualisation,aerosol band ,measuring plant health etc
You need the thermal band (which you dont have) to do anything like heat mapping, as for plant health you can do NDVIwhich i believe you must have seen in this video.
Dear Sir; that wasreally amazing video, and actually solved half of my problems,,,,indeed, many thanks. I have another question, I know now how to make any index for specific land cover, for urban, for agriculture, for water, for desert,,,,,the question is, how to overlay al of these indexes in one map, and know the land cover changes within 10 years time (2000 and 2010 for a certain area for example) also, how I can apply PCA? that will be really very supportive and help form you, Kindest regards
Abdelrazek Elnashar is right. The sine function within ArcMap requires the solar elevation angle to be in radians instead of degrees. You are using in your formula sine of deg not rads.
Hello Xenakis, the correction for solar angle like i said earlier is the sin(of sun elevation/angle). See link for reference as instructed by USGS landsat.usgs.gov/Landsat8_Using_Product.php
Hi there, can anyone please tell me is it necessary to do this calculation before I calculate NDVI or we can calculate NDVI without doing this calculation?
It is recommended that you do a correction like this one before you calculate any kind of indices from a satellite image. This is to reduce/eliminate the uncertainties in the original image.
I just calculated NDVI value of a sheet and it shows the value from -44.66 to 57.81, I don't know where I missed, I did exactly what you said but I used the whole sheet instead of clipped raster. Does that make any difference on the output?
Dear Usman Thank you for good video and I learn how to convert Digital Number to the reflectence, when I calculated NDVI and NDBI have incorrect answer for two index, for example the NDVI estimation about 170 for my photo and I know it is not correct (please guidance me). now if possible for you upload the video how I can estimation LST from Landsat 8 Image using software ENVI or another software because I think you are good teacher in this fiel.
Hello Shadman, there are several things that could cause error in your NDVI estimation. 1) Maybe you did not calculate the reflectance correctly, 2) Maybe you are mixing up the bands, make sure you are adding,subtracting, and dividing correctly, 3) Maybe did not specify that the NDVI needs to be in floating numbers from the raster calculator, these are what I can think of now. Re-check your process maybe you made a small mistake along the line, can you tell exactly how you did yours? As for the LST, I will make a video soon when I get a break for that. Thanks.
Hi Nimol, could you please give me a literature that has mentioned the methodology of the atmospheric correction, I need it for my thesis. Thank you in advance.
1. Reflectance values range between 0 & 1 unless any mistake happens during correction or the image has clouds.
2. In ArcGIS, don't directly use sin(x) or alike functions where x is in degree. Because ArcGIS read these functions values as radians. So always convert the values in radians before inputting it in sin/cos type functions in raster calculator or input only the value of the function doing math elsewhere(like him). Thanks
Thank you for sharing your knowledge. Looking forward for more videos from you sir :)
Your videos are very helpful in my study.
correct me if im wrong,
in the video, you process the Landsat 8 to produce TOA,
as far as i know, TOA (top of atmospheric) still includes atmospheric effect on the Landsat,
while SR (surface reflectance) excluding atmospheric effect.
Thank you very much for the clear and very useful video...good luck
Very very excellent video stuff. Very easy to understand ever.
Thank you for this useful video.
So is this atmospheric or radiometric correction? Also, what do I do when I have values like 7953 for high and -420 for low (band 5 LC8)? Please help - a beginner. Thank you all.
Very good dear Usman Buhari, excelent video.We are working with Landsat images on Uruguay, and use this video for atmospheric corrections.We are looking for summer crops on Uruguay, wich are regulated here by us: Ministry livestock Agriculture: the government, people have to creat 1 "soil use plan of conservation " for each agriculture crop plantation.Agonomist Martin Dell'Acqua GIS-MGAP-Uruguay Republic
Excellent! Pls, hv u got any video on LST calculation using raster calculator in arcGIS? I wonder what was the problem, but my output gives me too large value to consider as Celsius whenever I compute that.
This is not atmospheric correction. This is radiometric calibration and conversion to top-of-atmosphere reflectance. Atmospheric attenuation is not taken into account at all.
Hi Sean, could you please give me a literature that has mentioned the methodology of the atmospheric correction, I need it for my thesis. Thank you in advance.
@@इमान्दारनेपाली me too please!
You are welcome Mina, you need to have the Spatial Analyst license then activate the extension. Goto toolboxes and find it under spatial analyst - map algebra. As for Landsat thermal image what exactly do you want? The thermal image is band6 in Landsat TM and band10/11 in Landsat 8.
+Usman Buhari Hi! Thanks for an informative video. I am trying to Convert to Landsat DN value to TOA reflectance using your formula. But the problem is that I did not find any metadata like Band_specificReflectance_band and Reflectance_add_band. But I found radiance_mault_band_7 and radiance_add_band something like that (this metadata is for Landsat 1-3 images). I used this value following your formula and I got the NDVI value range is ok (-1 to +1) but red and NIR reflectance value varies. My question is now is it ok to use radiance_mault_band_7 instead of reflactance_mault_band_7. using ArcGIS 10. If it is not ok? What is the formula to convert Radiance to TOAReflactance.
Thanks for video. Is there really big difference in doing atmospheric correction of rugged terrain from a plug-in named Atcor in Erdas software as compared to the formula as given in video above?
I enjoyed your lecture, thank you.
Dear sir, can we use these atmospheric correction method for Landsat 5 and 7? Thank you in advance!
Thanks for your useful video. is not need there to multiply the sun elevation to 3.14 and divide by 180, and then take the sin value?
Hi, Thank you for an interesting video. Please can you clarify to me on the procedure for atmospheric correction. The conversion from DN to TOA is that a radiometric or atmospheric correction? If using other software like ENVI for instance which has a radiometric calibration tool and DOS or FLAASH, will your method still be applicable?
Excellent. Thanks Usman
Hi Thanks for this tutorial
I would like to know if I can use this atmospheric correction method before calculating LST using band 10 Landsat 8 OLI TIRS
Hii.. do u already got the answer? Could u share
Sir, what reference we can use for the above atmos. corr. of landsat 8 process?
Hello! Thanks for your good video, ive got a question, can i use this formula to make atmosferic corrections with landsat 5 and landsat 7 images too?
No you cannot use this formula for Landsat 5&7.
+Usman Buhari Hello, many thanks for the useful video! Would you explain how can apply this for Landsat 5&7 ? Thanks for advance!!!
This method only applies to Landsat 8 products.
+Usman Buhari do you know how to make the corrections for Landsat 7? Thanks
María, yo también ando batallando con la corrección con Landsat 7. Supiste como solucionarlo. Por qué miro el manual de usuario de Landsat y no lo entiendo.
I am having issues being able to load in/create the composite.tif image you have with the 3 visible bands. The data I have downloaded does not seem to have that raster. Was that composite.tif image created post download? or have I downloaded the wrong dataset (Level 1 GeoTIFF Data Product)?
Hey sorry for the late reply, what Landsat data are You trying to composite? You can atleast assume if your download was the right one by the size of the zipped folder downloaded. There also just .jpeg files that are in the download option, could they be what you have downloaded? If you downloaded the right files then the individual bands should have a unique naming convention like LN00019059165 this is not an actual name though, just for sample sake.
First i would like thank you for your amazing videos.
My question is that as my study area falls under multiple scenes due to large area. The sun elevation is different for different scenes. I want to know how to choose the sun elevation for different scenes as i have to mosiac them first, Then calculate Say NDVI, LST etc...
Same question.. Did you get the solution bro?
Hello Dr Usman could you please help me to evaluate my image after convert it to reflectance
Sir thank you much for your enormous effort in creating such a platform for GIS learners. Whatever I have learned about remote sensing and GIS, that forms your website and the page.
I am very much thankful to you I need your help I am looking for a tutorial on how to drive PM 10and PM 2.5 form Landsat 8 data. It will be a great pleasure for me if you kindly extend your helping hand.
which bands you used to make composite ,i am trying to estimate temperature give me some idea
Dear Usman, Thank you for this explanatory video. Could you please answer the following queries? Thanks,
1. I was wondering why you would do atmospheric correction after you had made the composite image. Are we not supposed to do atmospheric correction for all individual bands before making the composite? Or we can do that even after making the composite image?
2. Also, for calculating NDVI do we even need the composite or we can just do atmospheric correction for NIR and Red bands and just calculate NDVI values as you have done?
3. How can we plot the spectral signatures of various objects using this NDVI?
1. You should always do an atmospheric correction before anything (including the composite).
2. Since RED an NIR bands are all you need to estimate NDVI, you can use just them without doing a composite as seen in the video.
3. NDVI is mainly for vegetation analysis.
Thanks Usman. I was trying to do atmospheric correction for landsat 7 data. But I found that this formula would not work there as they haven't provided band specific reflectance values like those in landsat 8 metadata. How can we correct the landsat data for atmospheric effects and sun angle using raster calculater? Please help
Watch this th-cam.com/video/0EvuA6t1XH0/w-d-xo.html
annd again sir i have made the composite image........and i have been given with a .dat file which contains the training index values for 7 class .......how can i use that .dat file
Can I use Radiance_Mult_Band_10 for Band 10
wonderful , how can i get more tutorials like these
Hello Mr. Usman Buhari. Can Sin (sun_elevation) be negative? Cheers.
I have never seen a negative Sin(sun_elevation). What I do is use a scientific calculator to find the Sin then put into the raster calculator.
I calculated it on Excel...... I'll try on a scientific calculator.
Mr. Buhari. I probably made a mistake on calculating NDVI, I appreciate if you can help me with this. Atmospheric correction was ok. However, I run NDVI and raster output presents values ranging between -73,46 and 554,555 (Automatic on IMAGE ANALYSIS) and ranging from -29,32 to 129,2 (Raster Calculator). How do I get it in the correct range (0-1)?
Ahh i see, put the formular in raster calculator like this: float(NIR-RED)/float(NIR+RED). This should work if you did the atmospheric correction well.
Usman Buhari I've already did it. But it still not working well.
Hello, I would like to make atmospheric corrections to all my bands. Can I use the same formula (band spesific reflectance_mult_band x DN values + reflectance_add_band) for all the bands? For example for bands 1-3 as well?
Yes Ninna the formula is the same for correcting Landsat 8 data
Usman Buhari Thank you for your answer!
sir , i have only red,blue,green and infrared band .........what kind of image classification can be done by using these values
You can perform most type of classification. This still depends on what you are looking for with the images.
Would you mind telling some of them sir???becoz whatever tutorials i was watching .....each consisting 7 bands.....but i have been given only 4 band of an area....
How can i combine these 4 bands to show heat visualisation,aerosol band ,measuring plant health etc
You need the thermal band (which you dont have) to do anything like heat mapping, as for plant health you can do NDVIwhich i believe you must have seen in this video.
Dear Sir; that wasreally amazing video, and actually solved half of my problems,,,,indeed, many thanks.
I have another question, I know now how to make any index for specific land cover, for urban, for agriculture, for water, for desert,,,,,the question is, how to overlay al of these indexes in one map, and know the land cover changes within 10 years time (2000 and 2010 for a certain area for example) also, how I can apply PCA?
that will be really very supportive and help form you,
Kindest regards
why didn't you convert Sun elevation from degree to radian?
My brother
Sun Elevation angle or Solar zenith angle should be in (radius) before using it in the formula, isn't are?
Hi Abdelrazek, No the sun elevation should be converted to sin(of the sun elevation) not radius. Thanks for the support.
Abdelrazek Elnashar is right.
The sine function within ArcMap requires the solar elevation angle to be in radians instead of degrees. You are using in your formula sine of deg not rads.
Hello Xenakis, the correction for solar angle like i said earlier is the sin(of sun elevation/angle). See link for reference as instructed by USGS landsat.usgs.gov/Landsat8_Using_Product.php
thank you sir for this cours
Dear sir, could you please give names of any literature that I can cite for the procedure that you explained in the video? Many thank you in advance.
[www.gisagmaps.com/landsat-8-atco-guide/
How do I cite this methodology?
Hi there, can anyone please tell me is it necessary to do this calculation before I calculate NDVI or we can calculate NDVI without doing this calculation?
It is recommended that you do a correction like this one before you calculate any kind of indices from a satellite image. This is to reduce/eliminate the uncertainties in the original image.
Thank you very much for a prompt reply sir. Much appreciated.
I just calculated NDVI value of a sheet and it shows the value from -44.66 to 57.81, I don't know where I missed, I did exactly what you said but I used the whole sheet instead of clipped raster. Does that make any difference on the output?
jooyee99 If you still have the black area surrounding the actual image, you are likely to have strange values in your result.
Thank you very much, I calculated it by clipping my study area and results are good :)
Good job
Bonjour chers amis merci pour tout ce que vous faites, je voudrais que vous m'aidiez au niveau du logiciel ENVI
Dear Usman
Thank you for good video and I learn how to convert Digital Number to the reflectence, when I calculated NDVI and NDBI have incorrect answer for two index, for example the NDVI estimation about 170 for my photo and I know it is not correct (please guidance me).
now if possible for you upload the video how I can estimation LST from Landsat 8 Image using software ENVI or another software because I think you are good teacher in this fiel.
Hello Shadman, there are several things that could cause error in your NDVI estimation. 1) Maybe you did not calculate the reflectance correctly, 2) Maybe you are mixing up the bands, make sure you are adding,subtracting, and dividing correctly, 3) Maybe did not specify that the NDVI needs to be in floating numbers from the raster calculator, these are what I can think of now. Re-check your process maybe you made a small mistake along the line, can you tell exactly how you did yours? As for the LST, I will make a video soon when I get a break for that. Thanks.
another reason maybe can be not removing the black background of raw image
PLS CHANGE THE TITLE TO THIS TUTORIAL. THIS IS NOT Atmospheric Correction!!!!!!
hello sir, thanks for sharing this beneficial vedeo, but please sir how can i extract surface temperature from landsat 8 using ArcGis. thank you
Watch my new video on estimating land surface temperature.
thank you for responding to my request, i will sure watch that video.
False and Mistechnique.... This is not Atmospheric Correction and Surface reflectance, rather this is TOA only.
This is not atmospheric correction.
Hi Nimol, could you please give me a literature that has mentioned the methodology of the atmospheric correction, I need it for my thesis. Thank you in advance.
@@इमान्दारनेपाली me too please!
@@SolMarTraders search for "COST method"
Eugénio Maza thanks! I have used atmosc on terrset finally.
@Darren Who the fcuk asked you? Beeych!