flat port/dome port

Hi guys,

All along i thought that dome ports were for wa and flat ports were for micro. But i just found out recently that for the same macro lens, u can use a flat or dome port for it. What's the difference and which is better?

THanks,

Colin

One of the main reasons for using a dome for WA is that it preserves the lens' above-water angle-of-view ... and that's what we want for WA, after all. Macro can be shot thru dome ports, but there's not much advantage and there's the disadvantage that the larger dome port is harder to manuever and may make it harder to light your subject with your strobes. On the other hand, it can save you buying or carrying a port..

Hope this helps...

thanks Chris! yup it did help. I've read somewhere that a flat port for macro would cause 30% increase in magnification as compared to a dome port. is that correct?

Thanks,

Colin

Hi Colin

To answer you question, yes your about correct,

The flat lens of the port coupled with the air gap between your lens and the glass, leads to about a 25% incease in focal lenght of your lens

so

105mm macro would come out at about 130mm.... 105 x 1.25

This can be a bouns to us when shooting macro as it means we can stand off from our subject that little bit more & not not scare the hell out of it.

personally i've used

nikkor 60mm micro

tamron 90mm macro

nikor 60mm micro with 2x teleconverter

all behind flat ports, i've used zoomers behind domes and of course all my primes go behind domes. as the previous message says to maintain my lens's angle of view once it goes below the waves

all work extremely well with my setups..

hope this helps a little

regards

craig . Aquaimaging photography

thanks Craig! great help=)

Colin

Hi Colin

 

To answer you question, yes your about correct,

 

The flat lens of the port coupled with the air gap between your lens and the glass, leads to about a 25% incease in focal lenght of your lens

 

so

 

105mm macro would come out at about 130mm.... 105 x 1.25

 

This can be a bouns to us when shooting macro as it means  we can stand off from our subject that little bit more & not not scare the hell out of it.

 

personally i've used

 

nikkor 60mm micro

tamron 90mm macro

nikor 60mm micro with 2x teleconverter

 

all behind flat ports, i've used zoomers behind domes and of course all my primes go behind domes. as the previous message says to maintain my lens's angle of view once it goes below the waves

 

all work extremely well with my setups..

 

hope this helps a little

 

regards

 

craig . Aquaimaging photography

<{POST_SNAPBACK}>

Hi Craig, any problems with AF when you use a TC behind your 60mm?

Eric