Annecdotal one

[Ron Mahoney]

Thought the old strand had been quiet for a while; so here's one for you: You get down on a U-boat in 60m of water, the visibility is gin clear (20m+) bright sunshine overhead and plenty of ambient light. Your buddy swims around the wreck passing his 50w halogen light across the wreck. You W/B your camera for the available light and put up with the occasional red streak across your lens as his light catches you. The question is why does his light appear red on the bottom but turn more blue as you ascend? Surely it should become more red!

[10barpics]

Hi Ron and all,

I am not a expert. Just taking a stab. On surface different torch lights seem to glo a little different. Some are white some orange and even with newer type of bulbs and reflectors some even give a blue glo. So perhaps different torches different colour that glo from them, different results.

From my short experenice with video and light and with video if you hold your camera in the one spot wait for the sun to come in and out from behind clouds. Wait for the light from you torch to blend with the changing ambient light and wait for your buddy torch to blend has well, 3 different light sources in and out . The results are like if you are videoing 3 different wrecks.


Dive the U-89 recently as well. Pictures on http://www.10barpics.com.
If you look at the Folia pics you well see one of the pics all red perhaps from the rust in a tight area? Or the rust reflecting back up along the light in some way.

yours truly,

Jim

[Ron Mahoney]

Jim,

Great pictures of the U89, the workings of the stern tubes looks really good. Tell me do you "grab" the images from tape or do you store pictures to card/tape during the capture? Some of the stills seemed to be a much higher resolution than others. The shots of the inside are caused by the amount of rustin the area. Even under HiD lights and with you having w/b the camera you will always get results like that in tight enclosed areas of the wreck. Got to admit the shot of the conger is a corker - is that an unarmed torpedo or an air bottle (or some other machinery)it's got its head poking out of?  

What you're saying about the light is true; in the case I was taliking about, the diver had a 50w halogen light and on all the bottom footage you get the really red glow from the torch - as you'd expect from the additional red compensation the camera makes to white balance. The answer was that as I had neared the surface I had re-white balanced so obviously there was less red in the filter - should have posed it as more of a teaser. I've found that for about every 5m you descend you need to w/b each time - the same is true as you ascend if you are looking to take some deco shots.

Best regards

Ron  

[10barpics]

Thanks Ron,
             the pics are decompiled from the video. It is Seapro Housing with optiport. Camcorder is NV-GS22 very basic.No card in it for stills. Have not found the white balance on it yet if there is. Everything is set to auto. For lights, with the housing came the Seapro great white light on its own leveas an outer black circle. So to either side I have mounted adjustable arms with Aqua-vision umbical torches mounted. So 3 50w lights. A bit strong with I get close to object's. The U-89 is the first time I have used all 3 lights. Might change bulbs to 30w any advice?

At the moment software is ULEAD 6 very very basic an Aldi special offer. Hope to get some Adobe come the new year. And to get the stills I use OSS Video decompiler software. About 30,000 pics per half hour but to get good resolution from a frame takes a bit of searching. If I have read the manual probaly a frame is 800,000 pixles. So a long ways of 6m digi still camera. Light is the secert.

But as for the high resolution me thinks it is because I got to the stern free from other divers and free from the very harmless current.

I do not know what the conger is living in. Freindly fellow why most divers are afraid of them I never know.

But to the stern storage/torpedo room that is a real live torpedo all right. Hit that with a hammer if you dare ? A real challange for the shell collectors.

Over all video turn out all right. If you are the dive show. Barrie has it on his laptap and can show you. It is raw footage. When I get a handle on editing I will send you a copy on DVD.

yours truly,

Jim