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enter image description hereimage_2

The procedure went well. Image 1 represents the raster (Chelsa) of annual mean temperature (bio1). I clipped it using a shapefile of country boundaries and the resulting image is image 2. As you can see, there is a contrast difference between the layers and the legend values on the right also changed. If I use this clipped raster for my further analysis, will it have any adverse impact on the results. I have been behind this for quite sometime but Not Yet Resolved.

Response to @rumski20

  1. Downloaded .tif files from Chelsa (Image 1),
  2. Converted them into .asc files in QGIS 3.18 using Translate option. While translation, no data values were not given.
  3. Translated ASC files were clipped using shapefile while clipping No Data Values were assigned. No data values were sourced from the developer (Image 2).
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  • Can you report on some of the raster properties for the two images, such as resolution, bit depth, etc? Invariably, clipping a raster will result in resampling (and thus changing values), but your legend alludes to some other differences between the two datasets.
    – rumski20
    Jun 15 at 15:50
  • > image 1 dimensions : 20880, 43200, 902016000 resolution : 0.008333333, 0.008333333 (x, y) extent : -180.0001, 179.9999, -90.00014, 83.99986 crs : +proj=longlat +datum=WGS84 +no_defs source : bio1.tif names : bio1 values : 0, 65535 (min, max) --------------------------------------------------------------------- > image 2 dimensions : 17172, 43199, 741813228 resolution : 0.008333333, 0.008333333 extent : -179.9918, 179.9999, -59.46681, 83.63319 crs : +proj=longlat +datum=WGS84 +no_defs source : bio1.asc values : 2450, 3072
    – Dr. Rahul Raveendran
    Jun 15 at 17:05
  • There is certainly a change in range of values. The initial min/max almost seems like a potential rather than actual min/max. Can you list in detail the steps you used to go from image1 to image2?
    – rumski20
    Jun 15 at 21:23
  • 2
    Please Edit the Question in response to requests for clarification. As OP, it is your job to curate a complete, answerable Question. Comments are ephemeral and lack a full set of formatting tools. More importantly, it's not fair to those who would help to have to sift through comments for critical information.
    – Vince
    Jun 16 at 11:51
  • Okay, based on the procedure you outlined, my best guess is that raster type or bit depth conversion took place that altered your values. I would revisit the settings you used along the way at each step. Additionally, I would suggest taking the advice of @Vince and update your question with any/all information you can in order to increase your chances of useful responses from the community
    – rumski20
    Jun 16 at 19:21

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