Flat port or dome

[stano]

I currently own an ikelite housing for my slr. I am planning to fabricate a housing for a sony video camera. I was wondering if someone could tell if a flat port is only for macro. Seems like every flat port seems to say that in descriptions etc. I would like to use the same port mounting system that the Ike housing uses that way any ports I buy could be used with either housing. All comments welcome.

Stano

 

[stano]

Anyone? Camera is an XR500 if that helps.

 

[diversteve]

Flat ports are better for macro as they allow you to get closer. Since it's just a piece of clear glass, all the focusing is done with the camera. But the L&M Stingray, Top Dawg (cost-reduced Stingray) and new Amphibico Turtle only come with flat ports so they're obviously useful in other situations. Most video is shot mostly at wide angle anyway. Just be sure to allow for the FOV of the lens in your design or you'll get vignetting in the corners at full wide angle.

 

[ronscuba]

To follow up on what Steve says.

You know things look around 25% bigger UW right ? That's because of refraction and we look through a flat mask. A flat port maintains the 25% bigger look, plus it allows you to use the zoom on your camcorder. Those are the 2 reasons flat ports are recommended for macro.

A dome port corrects for the 25% enlargement, attempting to make things look real size. The curve of the dome tricks the lens to focus on a fixed position in front of the port. Because of this, zoom is limited. If you try to zoom past the fixed position, the image will blur.

The position of the lens in relation to the dome port is critical to get a good image. That's why many times you will see housing manufacturers recommend certain sized extension tubes for matching camera lenses to dome ports.

If you are making your own housing, a flat port will be much easier.

 

[stano]

Well I did a bunch of research and was either considering cnc milling my own case (buddy has an amazing cnc mill) or casting one out of acrylic. I did find what appears to be a great source for castable acrylics, www.smooth-on.com. Look up crystal clear on their site. Also have tons of great videos.

However I just came across a smokin buy it now deal on eBay and bought a new ikelite. The price was amazing so I hope the deal is for real. I will post back in a week or so.

So I really wanted to do this project but for what I spent I couldn't possibly build one.

Thanks for the comments did learn some things.

Stano