From the course: Learning Underwater Photography

Unlock the full course today

Join today to access over 22,400 courses taught by industry experts or purchase this course individually.

Contrast and focus lights

Contrast and focus lights - Photoshop Tutorial

From the course: Learning Underwater Photography

Start my 1-month free trial

Contrast and focus lights

- [Instructor] In this movie we're going to talk about what your camera needs in order to auto focus on a subject and that is contrast. And to explain what we mean my contrast we have Herigan. - [Herigan] As Diek mentioned most cameras rely on contrast and contrast is the difference in tone between two pixels and that's what it requires to focus. - [Diek] And we're you're talking about tone you mean luminance right, brightness between neighboring pixels. - [Herigan] Yes the difference in brightness or luminance between adjacent pixels is what's going to provide the contrast that the camera's going to need to auto focus. One of the issues is that underwater we have a lack of available light and this by definition leads to a lack of contrast, and that can cause difficulties for the auto focus system. So here we've got a fairly high contrast scene, lots of lights and darks and they're right next to each other. Zooming in here a little bit we can see that there's no problem finding some…

Contents