@Colin 'workflow'

[mrrod]

@ Colin Southern

I read your post in the thread 'Input to the HDR software - created exposures' with your example picture 'rocks and redish sky', would you have time in elaborating how you processed the picture? you wrote about 3X 30sec exposures for the rocks and another shot for the sky, i'm just wondering what your work flow was for this picture.

[Colin Southern]

Hi Rod,

Arrrgh - I'll have to think back a couple of years!

Think of the top and bottom as being different "zones" - the for the top zone I simply took one of the 3 RAW captures and processed it for the mountains and sky that I wanted (it's called "The Mountains and the mist - Revisited" by the way). As mentioned elsewhere, "redeveloping" a RAW file doesn't gain you anything in terms of DR, but it can make it easier to get the levels in areas without having to create difficult masks (more on this below).

The bottom portion is 3x 60-second images (sorry, I think I said 30-second before). In Photoshop you just stack them as layers and set the opacity to 100% for the bottom layer - 50% for the 2nd to bottom, 33% for the 3rd to bottom etc.

To combine them I them flattened the image - added the adjusted top portion as a layer - add a layer mask - and then with the brush set for a very low opacity, carefully hide one layer / reveal the other layer to create a transition zone between the two.

Easy eh

[mrrod]

Hey Colin,

Another quick question, your 3X60 second images, are they bracketed as any other HDR shoot? if so, could you explain to me how the under exposed shot keeps the shadows? I was thinking that 60 seconds would have let a lot of light in, I'm asking because I want to try what you did.

[Colin Southern]

Hey Colin,

Another quick question, your 3X60 second images, are they bracketed as any other HDR shoot? if so, could you explain to me how the under exposed shot keeps the shadows? I was thinking that 60 seconds would have let a lot of light in, I'm asking because I want to try what you did.

Hi Rod,

No - they're all the same exposure.

Stacking images like this has a number of advantages ...

1. Because the exposure is shorter, you can shoot with higher light levels (or less ND filter),

2. If you get the exposure wrong, you get a chance to correct it while there's still enough light

3. It reduces the noise to what you would have got at a lower ISO (eg 32 shots at ISO 3200 will be approx the same noise as 1 shot at ISO 100)

4. It effectively means that you can extend the exposure as long as you like

Here's a couple of shots to illustrate the example (by the way, these are posed in another thread here somewhere - if anyone can find it, I'd be eternally grateful)

A 1 second shot @ F16, giving soft waves ...



A combination of (off memory) 64 or 99 consecutive shots, gives mist ...