Working with Bitmaps

[BBatts]

Hello, I'm collecting bitmaps from a camera like below:

private void LPRCamera2_OnNewFrame(object sender, ref Bitmap NewFrame)
{
while (LPR2List.Count >= LowCamSettings.LPR2FrameCount)
{
LPR2List[0].Dispose();
LPR2List.RemoveAt(0);
}

        if (lpr2FrameIndex >= LowCamSettings.LPR2SkipCount)
        {
            LPR2List.Add(new Bitmap(NewFrame));   //List object
            lpr2FrameIndex = 0;
        }
        else if (LowCamSettings.LPR2SkipCount > 0)
            lpr2FrameIndex++;
    }

I then take the list (LPR2List) and pass it to a new object that copies the list to a local variable. Like so:

            for (int i = 0; i < LPR2List.Count; i++)
            {
                if (LPR2List\[i\] != null)
                    this.Plate2List.Add((Bitmap)LPR2List\[i\].Clone());  //Error Line
            }

Every now and then i'm getting an error when copying telling me that the object is in use. I haven't the slightest clue what I could be doing wrong. Any help would be greatly appreciated.

[TnTinMn]

I suspect that this is a threading issue. LPRCamera2_OnNewFrame appears to be an event handler and it may be raised on its own thread. See this SO answer[^] for a good explanation.