Focus Stacking Landscapes…and moving water.

I’ve done a fair bit of focus stacking in macro/closeup type stuff. I know it’s also used for landscapes and the question occurred to me “What happens when you stack photos of moving water? Does the water turn to mush? Does one use a faster shutter speed and let the “softening” come from the stack?”

I was all set to ‘speriment with this last weekend, but the little waterfall I chose to try this out on wasn’t moving - it was frozen solid!

Hi TwoWheeler,

I haven't delved into the grey art of focus stacking (yet), but - sort of loosely - connected with the concept of multiple shots and flowing water is this tutorial from Anthony Morganti about how to produce a silky cascade like effect from 'normal shots', which may be of interest to you or others.

(Where we tend to most often use multiple shots with waterfalls is if wind is disrupting the foliage when we'll blend one slow/ one fast in Photoshop).

Phil

TwoWheeler said:

I’ve done a fair bit of focus stacking in macro/closeup type stuff. I know it’s also used for landscapes and the question occurred to me “What happens when you stack photos of moving water? Does the water turn to mush? Does one use a faster shutter speed and let the “softening” come from the stack?”

I was all set to ‘speriment with this last weekend, but the little waterfall I chose to try this out on wasn’t moving - it was frozen solid

Click to expand...

It might depend on what processing program you are using to blend your stack of images. In Photoshop, in my experience, Photoshop uses the most detail from each individual image in the focus bracket group for each area of the image. This means that in moving water at a slow shutter speed, it will include the most detail that it can find in the water itself. So, it is trying to do exactly the opposite of producing mush.

In the end, if one particular frame/shot has water that looks the best to you, you can always use a mask on the other layers to hide the water and use only the water you like.

PKM-UK said:

how to produce a silky cascade like effect from 'normal shots',

Click to expand...

I’m not a fan of turning water to milk, so I try to find a level of motion blur that doesn’t look too fake - hence my question. I was wondering if you have to take the multiple shot factor into account when selecting a shutter speed. @Bryan Conner made a good point about using the retouching tool, so it currently seems like the answer is “no”.

Bryan Conner said:

It might depend on what processing program you are using to blend your stack of images.

Click to expand...

Helicon

Bryan Conner said:

This means that in moving water at a slow shutter speed, it will include the most detail that it can find in the water itself. So, it is trying to do exactly the opposite of producing mush.

Click to expand...

I guess my question stems from my attempt at using pixel shifting to take a waterfall shot (because you’re not supposed to!). That turned the water to mush. It was horrid.

Bryan Conner said:

In the end, if one particular frame/shot has water that looks the best to you, you can always use a mask on the other layers to hide the water and use only the water you like.

Click to expand...

DOH! It never occurred to me to use the retouching tool for that. I’ve only used it to fix halos and stuff.

If I can find a waterfall that isn’t frozen this weekend, I’ll have to give it a try and report back.

Okay, so I answered my own question: What does focus stacking do to moving water? And the answer is "Not a damned thing".

The first image is one from the stack, the second is four stacked images. Other than the odd difference in white balance (even though I copied and pasted settings from one to the other), there's not a whole lot of difference.

Even here with the small file sizes and compression, I can see more detail in the water drops and in the water itself in the stacked image in the bottom left corner. There are probably difference elsewhere as well. But, not anything that anyone besides us pixel peeping camera nerds would notice.

Bryan Conner said:

Even here with the small file sizes and compression, I can see more detail in the water drops and in the water itself in the stacked image in the bottom left corner. There are probably difference elsewhere as well. But, not anything that anyone besides us pixel peeping camera nerds would notice.

Click to expand...

Yeah, I did notice a little difference but nothing to be fussed about. I was picturing more of the horrid mess that resulted when I used pixel shift to take a waterfall picture. It wasn’t even really a proper stack - I just took a shot, guessed where to move next and took another one.

Edit: I found the pixel shift photo in question! (Thought I'd nuked it). Here's a section: