Hi Ignacio
I tried to reproduce the issue as follows:
// Save description to file
ImageEnView1.IO.LoadFromFile('d:\input.tiff');
ImageEnView1.IO.Params.TIFF_ImageDescription:='Tag 270';
ImageEnView1.IO.SaveToFileTIFF('d:\input_Out.tif');
// Ensure cleared
ImageEnView1.Blank;
ImageEnView1.IO.Params.SetDefaultParams;
ShowMessage( ImageEnView1.IO.Params.TIFF_ImageDescription );
// Ensure saved
ImageEnView1.IO.LoadFromFile('d:\input_Out.tif');
ShowMessage( ImageEnView1.IO.Params.TIFF_ImageDescription );
It worked fine in my test. Perhaps it is related to your source image. Please email me d:\temp\test1.tif
Nigel
Xequte Software
www.imageen.com