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blaisedouros

Member Since 23 Mar 2012
Offline Last Active Mar 20 2013 08:33 AM
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Posts I've Made

In Topic: Tokina 10-17mm vs Sigma 15mm in FX mode on Nikon D800

07 March 2013 - 08:22 AM

John, that second image is extremely cool.  Great perspective on the eye, it's a very humanizing shot.


In Topic: Amazing and hilarious pictures of human figures and uw life

31 January 2013 - 08:23 AM

This is great work, and a nice fresh perspective on what we usually see in UW imaging.

In Topic: Internal dome reflections.

17 January 2013 - 03:58 PM

Hope it helps! Moray Eel is just my current rating, my forum handle is blaisedouros which provides a huge degree of anonymity given that it's nothing like my name. Swear ;)

In Topic: Internal dome reflections.

16 January 2013 - 08:46 AM

I notice that it's primarily your UV filter ring that is reflecting like this; presumably it has a relatively shiny surface on it? This is likely the main cause of the issue. Have you tried shooting without this UV filter?

I have seen many people paint the shiny portions of their lenses with matte black paint to help alleviate this, especially lenses with shiny silver or gold rings on them. Since it's just a UV filter on the front, what do you have to lose by painting it matte so it doesn't reflect?

Notice how in each of these images you are shooting into relatively strong sunlight? When enough light hits your lens through the dome, it reflects onto the inside of the dome. So if you can, avoid pointing your housed camera directly into strong light sources that you know will cause this reflection.

In Topic: Need info/technique on Stealth Mode

07 November 2012 - 10:40 AM

But in theory, the red light should work for video, as long as you take custome white balance. Like I said, take a white balance of the white slate with the red light, so anything that has red/pink color now become the new white. This should work for close distance subject (macro), not sure about far/wide scene. I may just go with UK Aqualite, and get a red gel to play with it.


White balance works by reducing the gain on the sensor sites that are receiving higher amounts of one color and increasing the gain on the sites that are receiving less color to produce a balance between red, green, and blue to produce white light. If the only color the camera is seeing is red, there is no green or blue light to produce a white balance.

In theory, the only way that the camera could "correctly" white balance a scene lit with only red light would be to turn off the red photosites, producing a black image (since there's no green or blue light hitting the sensor at all). In practice, you might get some weird color shifts or green and blue noise in the image as the camera bumps up the green and blue gain. You'd be better off setting a regular white balance with white light, shooting with red, and just accepting the color shift. You could convert to black and white in post for a less jarring look.