Backscatter removal

[Andreni]

Dear all

I'm desperate. While diving in PNG we had a lot of plankton in the water which affected the pictures badly.

I usually work with Lightroom to edit my pictures and correct some of the worst spots. But for backscatter removal it is very tiring. I heard about a better way for removal of backscatter in Photoshop. Can someone explain it to me? But it has to be an explanation for dummies as my technical understanding is not very good...

Your help would be much appreciated.
Cheers
Andrea

 

[stepfen]

The first and most important thing to consider is the correct position of your lights/strobes. Do you know how to place them properly?
This should greatly reduce backscatter.
It also depends on the type of photography (macro, wide etc).

Post processing should be your last resort. I use lightroom's spot removal for up to say 10-20 particles. More than that, I usually discard the image.

 

[Ministryofgiraffes]

short of erin quigley's videos etc. i'm afraid i don't have much more to offer. I know it's a silly question, but im sure you have watched all of the tutorials on 'removing backscatter in photoshop'? i'm not sure who would be able to offer more than that, but i'm always keen to hear tips...

 

[D_Fresh]

You could (and probably already have) try the noise reduction functions, but I find them less than effective to say the least.... I'm afraid that your options are likely tedious Spot Removal or better light positioning, further away from "down the line".

But don't fret, I know it's frustrating, but it's all part of the learning curve we've all endured. I can even begin to count how many "fantastic" shots I've had to toss for various reasons (Both above and below the surface).

 

[Storker]

I'm far from a Photoshop expert, but in my limited experience it's rather difficult to automatically remove backscatter without seeing loss of other details.

You might try using layers. Mask out the subject on one of the layers, leaving only the background where you remove the backscatter using some kind of filter. The loss of detail may be quite acceptable for the background which may be more or less out of focus anyway. Then you mask out the background from the other layer and remove the backscatter from the subject manually. It might be that that method is less work.

 

[The Chairman]

Get closer to your subject and use ambient light. No, I'm not in the PNW, so I don't fully understand what you're going through. I just know that works here in Florida.

 

[Storker]

use ambient light

...and lose the reds.

I'm not in the PNW, so I don't fully understand what you're going through. I just know that works here in Florida.

At some latitudes, you have to go to 1600+ ISO to shoot ambient. At least quite a few compacts struggle with giving a clear image at 1600+ ISO. Heck, even my m43 shows noticeable image degradation at 1600+ ISO.

 

[peterak]

I use Backshatter (backshatter.com) to removed backscatter from jpegs. Not perfect, but quite useful for salvaging otherwise nice shots. $50, but they offer a free trial.

 

[The Chairman]

...and lose the reds.

Filters. I use them and they work great!

 

[Storker]

Filters. I use them and they work great!

Until a point.

No filter can restore wavelengths which aren't there. The only thing they do is to reduce the amount of light in the wavelengths where there's plenty, to make color balancing easier. Which means that at 15m in murky cold water, if you use a filter there's even less light hitting the sensor, so the filter makes your camera ramp the ISO even further. You may have an easier job balancing the R channel with the G and the B channel, but you can't get around the fact that now your camera fires at 4000+ ISO instead of at 1600+ ISO, degrading the IQ even further.

And at 30m in murky cold water, there just isn't any red - or yellow - left. At all. The only ambient you have is in the green wavelenghts. So down there, the only thing a filter does is to reduce the amount of light hitting your camera's sensor.