How to Sharpen High-ISO Photos

Sharpening photos taken at higher ISOs is a tricky thing, as you run the risk of making the appearance of noise much worse very quickly. This helpful video will show you how to sharpen high-ISO photos to enhance detail while still reducing noise.

Coming to you from Blake Rudis at f64 Academy, this video will show you the ins and outs of sharpening high-ISO photos in Photoshop (or Lightroom) while reducing noise. High-ISO files tend to have much less latitude, so it's important to be very precise in your edits. As Rudis shows, noise reduction and sharpening are interdependent, and you can't consider one without also taking into account the other. The biggest takeaway, I think, however, is that it's less about the amount of sharpening you apply (though that of course still matters) and more about masking it in carefully so areas of nuance show more refinement, while broad, uniform sections of the image (where noise is more immediately apparent and sharpening isn't needed) are left untouched, making the noise reduction more effective and resulting in a better overall photo. If you're someone who spends a lot of time in less-than-ideal lighting conditions (like a wedding photographer), really dialing in this skill will help you improve the overall quality of your output. 

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12 Comments

Evan Kane's picture

Too often people are afraid of raising their ISO. While it's indisputable that lower ISO is preferable for preserving maximum image quality, there is no reason to fear raising the ISO if it means you can get a shot that you wouldn't be able to otherwise.

Alex Cooke's picture

Sometimes for sure! If you're shooting on an ISO invariant camera, sure, keep it a little low. But if you're shooting on something like a 5D Mark III, your files will look drastically better if you get the exposure right in camera.

Samuel Flores Sanchez's picture

Yeah ISO is a critic element in the triangle. Tha's what it is called "triangle". Is the last one we have to raise if we want a clean archive but definitely is miraculous what can be achieved today with intelligent ISO use. I find that if you get the histogram to the right edge using the ISO when necessary, you have better levels of noise, and generally when you do that you have to twitch down the exposure a little which is good to for noise reduction in near black areas

Larry Whittaker's picture

That was one fine video on sharpening I subscribed. He does an excellent job of explaining it.

Gabrielle Colton's picture

Awesome, I can definitely use this I shoot high iso often

Most of my noise reduction use is with film scans. With my digital camera images it would usually be for instances of shadows brought up that then become noticeably noisy. In that case the tools in Lightroom/ACR are worthless since I only want the noisy shadows to be affected. For that, and all my other noise reduction needs, I use Noiseware. It's also a more competent and much more versatile noise reduction tool than what you get with LR/ACR. For example, in addition to being able to selectively affect noise in shadows, midtones and highlights, you can adjust noise reduction based on color.

As for sharpening, and apparently in contradiction to my selective use of noise reduction, I have no interest in selective sharpening. I also think the detail slider in LR/ACR is awful. I never use it.

I have no idea how well they will show up when posted to this site but attached are before and after cropped samples of noise reduction applied only to the shadows in Noiseware. Notice the lighter midtones of the street sign to the left are unaffected.

Edit: Click the first image to get the larger view and then use the arrows to toggle back and forth between the before and after.

The Noiseware plugin user interface.

Alex Cooke's picture

While you could do this in Photoshop, I would love if you split noise reduction into shadows/midtones/highlights in Lightroom. That's a neat functionality and a nice result you got!

Nice!
In Photoshop one could do much better:
1. Use Edge Maps to prevent sharpening of flat areas.
2. Use Multi Scale / Multi Frequency approach to sharpen mostly mid and low scales (Frequencies) which usually means higher signal to noise ratio.

There are many tools and plug in's to do that out there.

This was helpful. I usually use the High Pass filter for sharpening, but PS still requires me to go through the handful of steps required to execute it for some reason -- I would have thought there's be a solution that does all of that for you. So this is a good alternative.

See my answer above for one step solution.

Steve Cullen's picture

For sharpening high ISO shots, my favorite technique for Photoshop is to 1. Create a stamped layer, 2. Desaturated it, 3. Change blend mode to “Linear Light”, 4. Apply a high pass filter (play with various radii..usually 1.5 to 8 depending on subject), 5. Denoise the layer using NIK/NoiseNinja/etc. (apply high noise reduction and detail preservation to where noise is flattened but edges still visible), 6. Adjust layer opacity to eliminate ringing and other artifacts (typically to less than 50%...often times to under 30%), 7. Mask as needed (i.e., you don’t really want to sharpen Sky, clouds, or water).