Ikelite dome port 5503 is an 6 inch acrylic dome, used with wide-angle lenses for underwater photography.

Please watch video for HOW TO USE

https://www.youtube.com/watch?v=Y6MSAKIHOVk

https://www.youtube.com/watch?v=tZR1hKe-N5Y

see following chart to see compatible lenses for Canon/ Sigma/ Tamron and others

http://www.ikelite.com/images/products/housings...

*******Canon Lens Chart see below
Canon 8-15 mm f/4L EF USM Fisheye
• Zoom with 5509.28 zoom set - included with housing
• Dome shade must be removed to prevent vignetting"

Canon 15 mm EF f/2.8 Fisheye
• Vignetting will be present if using a full frame camera.

Canon 20 mm f/2.8 USM

"Canon 20-35 mm Ultrasonic
• Zoom with 5509.28 zoom set - included with housing
• Addition of a +4 close-up lens is required for this lens to focus underwater"

Canon 24 mm f/2.8

Canon 28 mm

"Canon 35 mm f/2
• Select a dome for the full angle of coverage underwater
• Select a flat port for sharper image quality, but reduced angle of coverage."

"Canon 35 mm f/2 IS USM
• Select a dome for the full angle of coverage underwater
• Select a flat port for sharper image quality, but reduced angle of coverage"

"Canon 35-80 mm
• Zoom with 5509.27 zoom set - included with housing"

"Canon 40 mm f/2.8 EF
• Select a dome for the full angle of coverage underwater
• Select a flat port for sharper image quality, but reduced angle of coverage"

Canon 40 mm f/2.8 EF STM

"Canon 50 mm f/1.4 USM
• Select a dome for the full angle of coverage underwater
• Addition of a +4 close-up lens is required for this lens to focus underwater behind a dome
• Select a flat port for sharper image quality, but reduced angle of coverage
• Flat port recommended"

"Canon 50 mm f/1.8 II
• Select a dome for the full angle of coverage"