DIY macro lens for gopro or intova hd cameras?

[RonFrank]

Sounds like we have a serious misunderstanding. Tele-converters like the Nikon TC20E will double the focal length at the cost of 1 stop. These can cost $500 and are like lenses with multiple elements and ED glass in the higher quality variety. They are large so several inches in length and go between the camera and the lens.

Macro filters are thin and thread on the end of the lens. There is no reduction of light adding a macro filter to a lens. You can get macro filters in a variety of diopters like +1 +2 +3. The +3 is a bit thicker than a UV filter. This is not a DIY project as filters are difficult to manufacture (melting sand to make glass) and they are cheap ~$20. More $$$ for larger sizes like the 82mm. I have used the +1 as a normal UW filter as it can help with normal focusing UW. While a macro lens will provide more quality these work well and are inexpensive. For $50 you can get a pack like +1 +2 +4 +10. They can be stacked.

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BTW this is standard for pros so do Not take the advice of those who obviously do not shoot UW much. These filters can be necessary to focus properly underwater. I left a +2 on my 18-35mm full time in Coz for normal shooting with my Nikon D200.

 

[vapourinthesea]

I agree there is a misunderstanding. First no one said anything about a teleconverter lens. And the Nikon TC20E is a cheap mans zoom lense. A true zoom lense with some serious glass can easily be $2000 and up. However, the op wants a MACRO lense. First, something every photographer knows is that the more glass there is, the less light is let in. So even your macro filter does (not much) cut down the light let in. Also, if they were so good (and so cheap) why doesn't any true photographer do anything but laugh at them. There is a reason their so cheap. Do they blow the picture up...some, do they cut down on light lost because its a single piece of glass...yes, but you get what you pay for. Those are horrible and are MUCH worse than the O.P. idea that he found. It comes down to optics, the way the glass is bent and shaped and treated, ect. That is a very nice picture of a turtle, but do you wonder why the turtle is barely in focus and everything else is terribly out of focus? It could have some to do with motion...though I doubt much at all since he is lit up with a flash. Its mainly the macro filters glass. And thanks for the website posted because it proves my point. Everyone look down at Macro10+.....see how its not focused and doesn't even look like the flower anymore? That's the effect that those have on pictures, the more the number is, the worse and worse it gets. I have used all the cheap macro solutions, and the cheapest one even worth trying was the op's original idea. Not great, but if he doesn't mind sacrificing some quality, it should work. But those macro filter things are junk. And you say these are standard for pro's, a true pro would never even touch one, and its far from standard. Aside from myself, I also have many photographer friends who wont even do a shoot for less than 5k and who run photography websites, mags, ect.