Hi David, I've messed with this a few times and ran into similar results as you in the past using the image control. What I did to get the result I wanted (showing each image at its original size) was to create a blank form (on the ribbong: Create -> Form Design).

In the properties pane for the form, choose the format tab.
Picture Type: Linked
Picture: [choose the path to your image - this can be managed programmatically in VBA as well)
Picture Tiling: No
Picture Alignment: Center - this will place the image at or near the exact center of the screen - similar to photo viewer
Picture Size Mode: Clip - this may seem counter intuitive, but it works once the form loads
Border Style: None
Record Selectors: No
Navigation Buttons: No
Scroll Bars: None - I use code to enable scroll bars if I have a very large image and I want to scroll to see it all

On the Other tab, set Popup to Yes, this ensures the full screen is available, however may have issues if you have multiple monitors but that can also be managed with code.

Lastly, on the Events tab, in the Form On Load event, go to code builder and add "DoCmd.Maximize"

This will load the form and show the indicated image  with the form in full screen view and the image at or near the center of the screen.

Things that help include setting a background color for your detail section if you don't want blinded by a white background behind your image. You can also bind your form to a table and have the On Current event change the "Picture" property of the form to the current record and handle any file path. You could set a button with arrow at the left and right of the form to navigate to next and previous, etc. Pretty much however you want it to look.

I should add, that I added some mouse/keyboard functionality for clicking on the form anywhere to close the photo view and have some hidden navigation as well. For example:

Details


Private Sub Detail_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
  
   If Shift = 1 Then
   ' Shift Pressed - Move Picture to next record in table or return to the first record
      If SelTop < Me.Recordset.RecordCount Then
      ' SelTop is the current position of the record cursor in the assigned record source
         SelTop = SelTop + 1
      Else
      ' Already at the last record, so go back to the first
         SelTop = 1
      End If
   ElseIf Shift = 2 Then
   ' The Control Key is pressed so go to the previous record or last record if already at the first record
      If SelTop > 1 Then
         SelTop = SelTop - 1
      Else
      ' Already at the first record, so circle to the last
         SelTop = Me.RecordSet.RecordCount
      End If
   ElseIf Shift = 4 Then
   ' The ALT Key is pressed, so close the Image Viewer Form
      DoCmd.Close acForm, Me.Name, acSaveYes
   End If

End Sub
Copy

Also, if you have issues with it not navigating to the last record initially with the code provided, then you likely have a lot more records in your table than I had so You may want want to do some behind the scenes record navigation with a recordset or clone and store the count in a variable to get the correct record count.

Thank you for the help!

Thanks for helping out, Donald. David, the key distinction is that Zoom fits the whole image inside the available space while keeping its proportions. Clip displays it at its original size, but any part that does not fit will be cut off. That applies to an image control too, so you can try Clip there as well as Donald's form-background approach.