For many years I have been asking the same question.
Why are people so concerned about taking photos, or filming the scroll we use in our Buddhist practice.
I finally found the answer today, after receiving the same answer from a variety of sources across the world.
Under the control of the priests and the Nichiren Shoshu sect mystery, exclusivity and secrecy shrouded the Gohonzon.
All this is still echoed in the way SGI members are concerned with taking photos of it, or allowing it in videos, as if it has magical powers some how taken away by the camera. Or that it would bring bad karma, or perhaps we might be "slandering the law"
(Nichiren's Gosho on what it means to slander the law, explcityly talks about the fact that slandering the law is about putting aside, or casting aside this teaching http://www.nichirenlibrary.org/en/wnd-2/Content/188, no mention of taking copies of the Gohonzon in any form.
Infact if you have ever thought about it, each Gohonzon you have in your home is a copy, and the fact that it was made by a machine, or a person is immaterial. It is the intention with which you use it, that is what matters.)
This practice of stopping people taking photos of filmmaking came about as a way of stopping people being disruptive during Gongyo, and it happened in the early days of the organisation.
It is simply not socially acceptable to take photos because it is rude, and is a distraction. If you allow one, person, then you will soon have the entire room snapping away.
Mobile phones and Cameras are a distraction and unless necessary should be left to the side, as when doing the Gongyo we should be focused on the Gohonzon.
So taking photos, and films is not because it slanders the law or it takes away the magical powers of the Gohonzon, but simply a case of politeness and etiquette.
It is a social etiquette that seems to have taken on a life of its own within our organisation and somehow become something much more than it was originally intended.
I know this because I have done extensive research across a number of countries and asked the same question to countless members who have practiced for 40+ years.
Let me give you another example from here in England:
Many centuries ago, mirrors were a prized possession of people who had money. They were very expensive and quite hard to get. Since the process for making them was rather costly.
To stop servants from damaging them, and being careless, rich people made up a story that if you break a mirror, you get 7 years bad luck.
This urban myth, spread like wildfire and soon across the country tens of thousands of servants spoke about this curse of breaking the mirror and always handled them with the utmost of care.
An urban legend was born.
It became common place that breaking mirrors brought bad luck.
So as you can see, what I have demonstrated from this story, is that the fear of copying or photographing the Gohonzon came from this very simple situation, handed down from the priest hood/early SGI days.
The Gohonzon is you. And the importance you put on the physical Gohonzon is a reflection on the importance you put on your self as a human being.
When we decide this object is worthy of supreme respect, a part of us has learnt that it signifies our enlightened state.
When we chant with it, we activate this potential, and each day, during Gongyo we are reminded of our infinite potential.
So please, help me in dispelling superstition, lets try to move away from this way of thinking.
It will only hold us back in our own growth, because we will continue to see the Gohonzon as an external power, object etc. when it is not, it all goes on within you.
The physical scroll does not contain wisdom, potential power, it transmits it.
Much like a book. A book is just ink and paper.
But when you pick it up, and read it, your mind puts all the letters together and the wisdom is activated, within your own mind.
So please, continue to respect this tradition of not taking photos, but keep in the back of your mind, that if you do take a photo by mistake, the mystic law isnt going to arrange for your imminent demise as if it was some kind of mystical hit man.
Respect the space during Gongyo, and focus on your prayers whilst doing them.
What is going on in your "heart"/mind" is where the real power starts.
A half hearted gongyo including phones and photos, is a half hearted Buddhist practice.
Focus on the sound of your voice, to the exclusion of all else.
nam myoho renge kyo
nam myoho renge kyo
nam myoho renge kyo