ParkerS 0 Posted January 9, 2022 Does anyone know if a flat port effects focus underwater like a dome port does? Share this post Link to post Share on other sites
SCUBA Hank 5 Posted January 9, 2022 What are you trying to ask? There is no negative effects on focus from a flat port. Dome ports operate a little differently as the camera is seeing the reflection on the inside of f the dome. Share this post Link to post Share on other sites
ChrisRoss 150 Posted January 9, 2022 24 minutes ago, ParkerS said: Does anyone know if a flat port effects focus underwater like a dome port does? the issue with a dome port is that the virtual image is curved and very close to the dome so you lens needs to focus quite close. You also need to stop down enough to get all of the virtual image in focus . A flat port does not have these issues, it does however magnify the image about 1.3x in water. Technically it does create a virtual image, but that merely appears closer which is the cause of the 1.3x magnification. For practical p=application though there is no focusing issue associated with a flat port. This link provides a detailed explanation: https://oceanity.com.au/articles/view/understanding-flat-port-and-dome-port-theory Share this post Link to post Share on other sites