Winter 1998 Newsletter

Cheap plastic domes on expensive cameras?

Optical Glass Domes Ports!

Does it seem odd, perhaps a bit foolish, that we housing users spend thousands of dollars on the very finest cameras, pay top dollar for the very best wide angle lenses, fork out additional thousands for our housings -- all to maximize the image quality for our underwater photos -- and then ultimately shoot through cheap plastic dome ports! Would you put a cheap plastic filter over your finest Nikon or Canon lens? If you use a housing, you already do!

Optical glass ports are plainly superior!

I am in the process of assembling the names of underwater housing users who may be interested in obtaining precision ground, optical glass dome ports for their housings. Why ground optical glass ports?  Quite simply, they are superior to acrylic ports in all ways. They offer greatly improved light transmission, resulting in better sharpness, color and contrast. Just take your plastic dome port off your housing, hold it a foot or two in front of your eyes, and peer through the dome at a light source from the inside looking out.  Pretty ugly, yes?  Notice the loss of sharpness and color saturation. (Sure, the outside scratches are reasonably well filled-in by the water. But you'll notice plenty of scratches on the inside as well.) And this is what your expensive, high quality lens must look through!  Even gently wiping the inside of a plastic dome with the softest of lens cloths results in permanent micro-scratches which degrade image quality further. And even a brand-new dome cannot match the fine tolerances and light transmission of a precision ground optical glass port. So again, would you ever even consider putting a plastic filter over your finest lens prior to shooting? But that is what we are doing with plastic dome ports. Commonly available dome ports are nothing more than compass domes adapted for housing use. Compass domes were never intended to be used photographically, and for good cause!

Top quality comes at a price

For these reasons, high-end users, like Hollywood or the Navy, use optical glass ports instead of plastic.  For them of course, money is no object, as cost is the reason why plastic is all that is available to the consumer in larger diameter size. I am working with a maker of just such precision optical glass domes, a manufacturer who makes domes for the Navy, broadcast T.V. and the Hollywood film industry.  We are looking at producing an 8" (inside diameter) glass dome, utilizing the finest Schott Optical BK7 glass. Such precision domes are extremely expensive when produced in small numbers. They can cost $8000 or more each!  (No problem for the Navy or Hollywood.)  However, in quantity, we can probably get the cost down to around $2300 to $2500. With enough orders, they could get cheaper yet. Yes, this is still high, but remember, the dome is the outer element of your lens system. Your image can be no better than the worst element in the optical system. Presently we housing users are putting what amounts to a cheap, plastic, low tolerance, low precision lens over our primary lens.

Taking waitlist names now

For the moment, I am only collecting names of those who might be interested.  Naturally, I want to be confident there are enough housing users who demand the best the system can deliver, and who see the utter folly of spending all kinds of money on cameras and lenses, only to cap the system with an inferior optic.  We will produce the dome only in the common 8" diameter, with a 3" depth (similar to Aquatica). We are also working with a custom machinist to produce mounting rings for many of the top housings. This will add to your cost. This option will not be for everyone, and will only be of interest to those whose demands for excellence are uncompromising. Speaking for myself, this will be worth the price.  Contact me by phone at (970) 927-9789, by fax at (970) 927-9708 or e-mail at cnewbert@csn.net if you feel the same. I will forward complete specs and final cost once I can determine the number of possible buyers and whether this project is economically feasible.

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