hi there can you help me I couldn’t go on because I am getting this error box all the time
this is memory related, SNAP needs more RAM to compute this task. How much is installed in your computer?
the RAM is 4GB
Unfortunately, that’s not enough.
8Go is the bare minimum and I recommend rather 16Go.
I hope you’ll find better equipment.
Thank you for the information but can you tell me that is SNAP toolbox is the only way to preprocess sentinel-1 image because we can use ArcGIS to radiometrically calibrate for Landsat image
There are alternatives to SNAP, some are free and others are commercial. However, note that Sentinel-1 images are very large. Using other software will lead to problems of the same type. You can work with very small subset if needed
I want to say thank you so much for all of you now I have gat 16 GB RAM and it is working properly
i have gat back scattering dB and i want to select some pixels to take ground truth measurement for soil moisture but i want to know that do i need georeferencing the image
once you have gocoded your image (perform range doppler terrain correction as a last step), you can use the pin manager to extract the backscatter intensity of a pixel together with its lat/lon coordinates.
The pin manager is explaned here: https://www.youtube.com/watch?v=5znAQH6vrLs
thank you so much for the help you don’t know how much you are helping me
Is there any way to import my study area in snap
hi there when I download an image of sentinel-1 the date on it says
Sensing start: 2019-07-22T03:17:51.550Z
Sensing stop: 2019-07-22T03:18:16.548Z but how can I know it is in taken in the day or night time (AM?PM)
time is always given in UTC: https://time.is/en/UTC
okay. is it possible to know on the image the sensing time is in the day or night time (AM or PM) if there is some way to identify thank you.
I don’t think there is a metadata tag for it, sorry.
May I ask why does it matter to you if the image is acquired at day or at night?
because I am going to collect soil moisture samples and I have to take the measurement exactly at the time Sentinel-1 overpass my study area which is found in Ethiopia and the time difference of Ethiopia from UTC is +3 it is found in Eastern Africa Time zone (EAT) but am not clear that the image is taken in UTC AM or UTC PM
UTC is actually a 24 hour scheme and doesn’t make use of AM or PM
You can use this converter to see which EAT corresponds to which UTC https://savvytime.com/converter/eat-to-utc
Hello. I have got a problem of getting an image of Sentinel -1 the last image which was taken in my study was on 03/08/2019 Since the revisit time of this satellite is 12 days I should have an image in 1408/2019 but there is no image after 03/08/2019 does some one has the clue why this is happning?
you can check for changes in the acquisition sements here: https://sentinel.esa.int/web/sentinel/missions/sentinel-1/observation-scenario/acquisition-segments