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04-05-2014, 07:43 PM   #1
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Need advices for making my own flash extender (fresnel lense)

Hi, i am making my own fresnel lense, (i cannot buy better beamer in my country), and i have a few questions.
There are two types of fresnel lenses here: acrylic and PVC, wich should i pick (PVC is cheaper, but if acrylic would give me better light quality nd quantity i would go for it, altough i dont think this is the case).
What dimmensions? ( i read somewere that it should be 12x14 cm for a 3 stop increase, ( i would cut it 12x16 because i would probably loose 1cm making the grip on each side), and that it should be at 15cm of the flash, is all this correct? ( i will be using it with a da*300)
Thanks for yor help.


Last edited by carlosodze; 04-05-2014 at 08:47 PM.
04-06-2014, 12:24 AM   #2
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Acrylic vs. Polycarbonate: a Quantitative and Qualitative Comparison -

This probably answers your question. I think the last two points of acrylic vs pvc are what you wanted to hear .

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