Je joins un code trouvé sur le NET pour copier l'image de la feuille vers un fichier :
'Based on http://www.jpsoftwaretech.com/export-excel-range-to-a-picture-file/
Private Sub Save_Object_As_Picture(saveObject As Object, imageFileName As String)
'Save a picture of an object as a JPG/JPEG/GIF/PNG file
'Arguments
'saveObject - any object in the CopyPicture method's 'Applies To' list, for example a Range or Shape
'imageFileName - the .gif, .jpg, or .png file name (including folder path if required) the picture will be saved as
Dim temporaryChart As ChartObject
Application.ScreenUpdating = False
saveObject.CopyPicture xlScreen, xlPicture
Set temporaryChart = ActiveSheet.ChartObjects.Add(0, 0, saveObject.Width + 1, saveObject.Height + 1)
With temporaryChart
.Border.LineStyle = xlLineStyleNone 'No border
.Chart.Paste
.Chart.Export imageFileName
.Delete
End With
Application.ScreenUpdating = True
Set temporaryChart = Nothing
End Sub