Getting the reflectance value and exporting the image

Hi,
I downloaded Sentinel 2 data from SciHub and now trying to analyze it in matlab. First I tried to read the image directly to matlab but after I divide it by 10,000 I still get values higher then 1 (max is 1.7). Does anyone knows how to do it right?
How can I make one file with 4 bands (2,3,4,8) and export it?
When I try to export the RGB image as TIF I get the message: “Writing this image as GEO-TIF/Big TIF is not possible. Cannot write multi size products. Consider re sampling the product first”.
I can’t seem to export one band at a time. When I try to add layers through the layer manger and then export it I seem to get the same matrix duplicated 4 times. Every same 4 pixels in the image are the same value
Any help will be much appreciated!
Thanks Eshkol

Exploring the tutorials will help you

http://step.esa.int/main/doc/tutorials/sentinel-2-toolbox-tutorials/

Dear Eshkol,

  1. The reflectance values greater than 1.0 are due to saturation, I expect to find these values over clouds or very bright objects.
  2. In order to export the image in GeoTIFF/BigTIFF you should resample all the bands at your desired spatial resolution [Raster --> Geometric Operations --> Resampling] without saving. Once your new product appears under the Product Explorer window you can select it and subset (resize and selecting the needed bands) [Raster --> Subset…]. Selecting the new product under the Product Explorer window you can export it in GeoTIFF/BigTIFF (File --> Export --> GeoTIFF/BigTIFF).

Regards,
Fabrizio

Thanks a lot Fabrizio that is very helpful!!!

Hi Fabrizio, I was wondering if you can explain why would a saturated pixel have a value bigger then 1 and not 1, how can I tell between the difference of a cloud or a saturated pixel? I am interesting in the clouds so its important to me.
Do you know where can I get knwoledge about these things cause I couldn’t find it.
Thanks again,
Eshkol

Dear Eshkol,

Please find below the answer to a similar post given by Dr. Olivier Hagolle

Regards,
Fabrizio

Thanks again you have been very helpful!!!