Wide angle lens options

[ETJ]

This is what I have for filter with the semi fisheye lens:

There seems to be small dead bug inside my housing

And this is my macro (& normal "wide") setup:

 

[BabySweetlipsLover]

View attachment 204620

Are these lenses really $900???? I know I'm a camera noob (hence the GoPro).

Are there any other cheaper options? Do you guys use the wet connect under water? How do you store the different lenses?

 

[tamas970]

I payed ~450$ including taxes and shipping (sd cage +ufl-g140), even with the macro you'd stay below 700. For macro
I intend to use my UCL-165. I know, there are really good+cheaper alternatives for macro (Macromate) but I have this lens
for my Olympus rig anyway.

Are these lenses really $900???? I know I'm a camera noob (hence the GoPro).

Are there any other cheaper options? Do you guys use the wet connect under water? How do you store the different lenses?

 

[tamas970]

First experience from today's dive: it seems, that the corners are very soft, from an expensive solution like that I'd expect a sharp image, corner to corner... Tomorrow I'll take some wet lens-no lens comparison shots.

Also very annoying: I can't see the LCD while the lens is mounted. To make sure, that the camera is on, one has to remove the lens - or never let the cam turning off.

 

[Interceptor121]

First experience from today's dive: it seems, that the corners are very soft, from an expensive solution like that I'd expect a sharp image, corner to corner... Tomorrow I'll take some wet lens-no lens comparison shots.

Also very annoying: I can't see the LCD while the lens is mounted. To make sure, that the camera is on, one has to remove the lens - or never let the cam turning off.

Corner sharpness is a known issue with dome ports
I think the default aperture of the go pro is quite wide so even with a tiny sensor you could have a problem there

 

[tamas970]

Corner sharpness is a known issue with dome ports
I think the default aperture of the go pro is quite wide so even with a tiny sensor you could have a problem there

Correct about domes, but this is NOT a dome! This is a modified Ivanoff-Rebikoff converter with aspherical element.

 

[Interceptor121]

Correct about domes, but this is NOT a dome! This is a modified Ivanoff-Rebikoff converter with aspherical element.

The problem remains the same due to the curve

 

[tamas970]

The problem remains the same due to the curve

A lens system can be designed to provide a flat image, just as the nikonos lenses - they also had dome front elements (eg: Borut FURLAN Underwater Photography) and provided stellar results on 35mm film. The g140 is a lens system, 4 elements in 4 groups - probably they had to make compromises between price, size and quality...

 

[Interceptor121]

I know inon system pretty well. They usually have a multiple element flat glass that if you use as is its sharp in corners but doesn't go more than 110 degrees. When you add an air dome on top of the lens the corners get less sharp. This is not an issue when you shoot a small sensor at reasonable aperture but I think the go pro is f/2.8 even with a tiny sensor maybe you have some challenges. The adapter also corrects fringing and other aberrations so it's not just sharpness

 

[tamas970]

Yepp, the hero4 is f/2.2. Later I might mod the camera with a narrower lens, around 3.5mm focal length, but need to do some more research, how useful that would be underwater (and how well would it go with the g140, since the flat port remains an issue)