Stupid question from a non-cave-diver

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Peter Guy:
Please explain to me, in simple terms if you can for people like me who are physics impaired, how using several (let's say 4?) focused HID lights will light up a cave so that the single diver can see the huge stalagmites/tites in the "cathedral" atmosphere of the photographs?

Is there enough defraction/dispersal of the light to get the whole image or is it just a series of mental snapshots?

When I've been in a dry cave, unless there has been a general light source, only that which is directly lit is viewable. And watching the HID's underwater at night (or otherwise in the dark), the illumination has been pretty darn focused.

Obviously there is much to see in caves, but, without a general light source, how is it seen?
I'm no physicist, but I'll tell you about my personal experience.....

First, I'm not a cave diver, though that's something I have been interested in since before learning to dive, but I've been into some "caverns" and swimthroughs that technically I should not have entered :wink:

These caverns and swimthroughs are basically mini-caves with exits that are easy to find using some "uncommon sense," even if some bozo screws up the viz. What folks say about dark is true ~ there is no dark like the dark of a cave.... dry or wet! Unlike dry caves, the water actually seems to help with the dispersing of the light beam. My 18W HID is focusable, which means I can make it a smaller beam for signalling or a wider beam for covering more area. What I've found in dark, dark places is that the wide beam is awesome for lighting up the structure and formations of caves. It's way cooler to see these in context than in little snippets caught in a narrow beam. It's a fascination that is impossible to describe to someone who has not seen it or is not interested in such things. If you look at the few "Chandelier Cave" pics I have in my Gallery, you can see how well my HID lit things up even for pics with my little point~n~shoot digital camera. The little built-in flash would never be able to light things up that much in the underwater shots (the ones that say "chamber' were actually not underwater, but the rest were). It's only good for up to about 12-16", depending on viz.
So.... point is, if the diver is interested in the stuff to be offered via a cave dive, an 18W HID will illuminate plenty more than a narrow beam of view. Also, the allure of cave diving to me is much more than that which is to be seen. Kind of like tech diving for me... Going there to see the structure and/or life is primary, but part of the allure is the planning and preparing and talking about and executing the actual dive with a favorite "buddy."
 
500 dives? Well, longer than a two year plan, then. Have done Fundies and will be working on those skills. Got a long way to go.

I watched the Budapest video and was amazed that there would be such an extensive cave system in the middle of the city!
 
Jason B:
wb416:
The darker walled caves DO seem to suck up the light and only what is pointed at is seen.

bob
PIII comes to mind....:evil:
Telford too. I hated Telford when I dove it during training. When I went back to dive it "for fun" I fell in love with it. Unfortunately it's been under every year I've been back since then... :(

Roak
 
I hate you guys. I probably live an hour from Telford, and it'll take me 3-4 years to be good enough to go in there!

How much training can you pack into a year anyway! :)
 
roakey:
Actually all caves form underwater. The Mexican caves were formed before the last ice age and looked just like the Florida caves of today. During the ice age the water level dropped and the Mexican caves became "dry" caves and became decorated. After the ice age when the sea levels rose, they became underwater again.

It's a pretty rare series of events and conditions, and though I'm sure there might be some decorated underwater caves elsewhere, nothing approaches Mexico.

Roak

I'm no geologist so I'm open to being corrected but though all solution caves are formed by water (or so the theory goes), not all of them have been under water for any extended period of time. For example, the caves of In, Kentucky Tn and so on.
 
wb416:
phfffffftttt!!

Everytime I've tried to get to Telford while I was in the area, it was heavy tannic.

I've gotten in their a few times but at the times of the year I end up going down there it seems like it's blown as often as not.
 
https://www.shearwater.com/products/teric/
http://cavediveflorida.com/Rum_House.htm

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