Spring clamp secures the pattern with an equal pressure around its complete diameter. This is important because it helps ensure the best in focus projection across the pattern image. Other holders grab the pattern at 3 or so points and as the pattern expands and contracts with the heat they distort and buckle. As a result the image can never be evenly in focus across the beam.
The image can be aligned on stage as required by simply rotating the holder in the gate. No need to take the holder in and out to realign the pattern in the holder…and no burnt fingers in the process!
The holder is a 'sandwich' style holder to clamp metal gobo's firmly and can also be used with home made acetate gobo's.