Get bitmap from clipboard problem

I have a program where I'm copying a bitmap from the clipboard and
displaying it. It seems that after I perform this operation a few
times (3-4) even after confirming there is bitmap data on the
clipboard {if (iData.GetDataPresent(DataFormats.Bitmap))} when I get
the data it returns null.

I have made a simple test case in MSVC.NET

File->New->Project->Windows Application. Under the
InitializeComponent() I added this simple test case.

for (int i = 0; i < 10; i++)
{
// Get the image from the clipboard
IDataObject iData = Clipboard.GetDataObject();

// Make sure we have a bitmap available
if (iData.GetDataPresent(DataFormats.Bitmap))
{
Image kImage = (Image)iData.GetData(DataFormats.Bitmap);
int t = 0; // So we can see kImage in debugger
}
}

The first 3 times kImage will be a System.Drawing.Bitmap object.
Afterwards it will be null.

I can only imagine that there is some sort of resource limit I'm
coming up against (This is my first C# project). I'm using a "print
screen" capture (3120 x 2400) which is quite large.

Remember to put something on the clipboard to test. Printscreen works
great.

Thank you in advance for any help you can provide!

Christopher