Here a simple example:

Private Sub Command1_Click()
  TChart1.Export.asJPEG.SaveToFile "e:\\tmp\\testAXSize1.jpg"
End Sub

Private Sub Command2_Click()
  TChart1.Width = TChart1.Width + 1000
  TChart1.Export.asJPEG.SaveToFile "e:\\tmp\\testAXSize2.jpg"
End Sub

Private Sub Form_Load()
  TChart1.Aspect.View3D = False
End Sub

- Click on Button1
- Click on Button2
- Compare the images generated. Both testAXSize1.jpg and testAXSize2.jpg have the same size. This is wrong.

- Then close and restart the application
- Click on Button2
- Now testAXSize2.jpg has the updated and correct size.

This doesn't happen in VCL with the following code:

uses TeeStore, TeeJpeg;

procedure TForm1.Button1Click(Sender: TObject);
var exportFormat: TJPEGExportFormat;
begin
  exportFormat:=TJPEGExportFormat.Create;
  exportFormat.Panel:=Chart1;
  exportFormat.SaveToFile('e:\tmp\testVCLSize1.jpg');
end;

procedure TForm1.Button2Click(Sender: TObject);
var exportFormat: TJPEGExportFormat;
begin
  Chart1.Width:=Chart1.Width + 100;

  exportFormat:=TJPEGExportFormat.Create;
  exportFormat.Panel:=Chart1;
  exportFormat.SaveToFile('e:\tmp\testVCLSize2.jpg');
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  Chart1.View3D:=false;
end;