Sharpening a Diffraction Limited Photo

Those of you who know me, know that I prefer to shoot single frames at F11 or higher. One way to deal with diffraction is to carefully sharpen an image. No, I won't recover detail that's lost to diffraction -the computer will never be able to recover data that I didn't record with the camera. But you can decrease the level of "perceived diffraction softening". The trick is to sharpen an image without introducing a lot of noticeable artifacts.

A few days ago I bought a license for Topaz Labs Sharpen AI (used my own money, so this isn't an add in disguise). Here's a shot taken at 5x and F11 processed with Topaz Labs Denoise AI, Sharpen AI, and Clarity (contrast adjustments). I'll let you decide if it looks good for a single frame.

Tech Specs: Canon 80D (F11, 1/250, ISO 100) + a Canon MP-E 65mm macro lens (5x) + a diffused MT-26EX-RT with a Kaiser adjustable flash shoe on the "A" head (the key), E-TTL metering, -1/3 FEC, second curtain sync. This is a single, uncropped, frame taken hand held.

IMAGE LINK: https://flic.kr/p/2gSR​eWY

Wow! That's done a great job. I usually open up to f/5.6 or somewhere around there at 5X but still end up with images similar to your unsharpened version.

I may have to look in to Topaz. I've heard good things but actually seeing the before and after has me interested.

thomas-b wrote in post #18912729
Wow! That's done a great job. I usually open up to f/5.6 or somewhere around there at 5X but still end up with images similar to your unsharpened version.

I may have to look in to Topaz. I've heard good things but actually seeing the before and after has me interested.

Thanks! You can download Topaz plugins and try them for free for 30 days to see how you like them.

That looks really good. I use the program occasionally but it is too cpu intensive for every shot. It does a brilliant job with wind motion.

ECC233 wrote in post #18921883
That looks really good. I use the program occasionally but it is too cpu intensive for every shot. It does a brilliant job with wind motion.

I'm now just using the Sharpen AI plugin because it removes sensor / exposure noise as well as sharpening a photo. Actually seems to work better if I use it first.

Dalantech wrote in post #18922093
I'm now just using the Sharpen AI plugin because it removes sensor / exposure noise as well as sharpening a photo. Actually seems to work better if I use it first.

Yup. That's what I am doing as well. Just try it on a a7riv file though!

I find that dXo Photolab's 'Lens Sharpness' tool does a very good job of getting similar results when used with the 'Prime' noise reduction tool. I do occasionally use the Topaz tools in Photoshop as well but DxO gets used the most I think.

With just 3 photoshop filters, you can get very close to the same results.

1) Unsharp mask to add very, very fine detail
2) Unsharp mask to fix contrast
3) SmartSharpen using .1, 125 fixing lens blur


Not quite the same, but very close, USM is a very powerful tool, many use it to just sharpen an image at various levels, but the micro contrast control it gives is quite versatile.

TeamSpeed wrote in post #18956430
With just 3 photoshop filters, you can get very close to the same results.

1) Unsharp mask to add very, very fine detail
2) Unsharp mask to fix contrast
3) SmartSharpen using .1, 125 fixing lens blur


Not quite the same, but very close, USM is a very powerful tool, many use it to just sharpen an image at various levels, but the micro contrast control it gives is quite versatile.

I use to use USM quite a bit, but I like the granularity I get with the Topaz plugins, and the new AI plugins offer a split screen view with a slider so it's easy to see how much of a change the plugin is going to make. Also I'm sharpening first, then removing image noise, then contrast adjustments. In the past sharpening without removing noise first didn't work so well, but Sharpen AI seems to work better before noise reduction. Here's the most recent file I've processed:

Tech Specs: Canon 80D (F11, 1/250, ISO 100) + a Canon MP-E 65mm macro lens (about 3x) + a diffused MT-24EX (both flash heads on the Canon flash mount, E-TTL metering).

IMAGE LINK: https://flic.kr/p/2hGb​ub3

IMAGE LINK: https://flic.kr/p/2hki​pdf

Dalantech wrote in post #18922093
>snip. Actually seems to work better if I use it first.

I think that Topaz recommends using AI Noise Reduction as the very 1st process step, so it performs its magic on the raw data (providing you shoot Raw).

Cheers

Dennis

nardes wrote in post #18956502
I think that Topaz recommends using AI Noise Reduction as the very 1st process step, so it performs its magic on the raw data (providing you shoot Raw).

Cheers

Dennis

I've tried it both ways, and it seems to work better with sharpening first. Got a link on the Topaz site where they go over work flow?

Edit: FWIW: Both Sharpen AI and Deoise AI plugins will sharpen and remove noise. But using both of them is worthwhile.

Edit2: This article recommends applying noise reduction first, but was written before Topaz released the AI plugins. Yet another thing on my weekend "to do" list is to process the same image twice, one with noise reduction first and the other with sharpening first and then compare them. In my informal post processing sharpening first seemed to work best, but I suck at post processing so it's worth testing to see what works best.

Ninja edit: I'm probably wrong, because this recent article recommends removing noise first.

I usually remove noise first, but it depends on the type and quality of noise. When noise was "blobby", you wanted to remove it first. As resolutions have gone up and noise became more grain-like, I will often run some sharpening (minor) on the image, and then tackle the NR.

I took a Raw SOC image of a Galah at full resolution and cropped it to 1200x1200, then processed it with the following Topaz Labs Plug Ins at their default settings:

Denoise AI
Sharpen AI

You can see some differences at the pixel peeping level on my screen and I am not sure how this will translate to the saved JPGs as viewed here. One quite noticeable difference is that DeNoise AI has removed the fine, granular detail in the eye of the Galah, whereas Sharpen AI has managed it better.

Viewing the originals, it looks like the fine feather details show a greater degree of sharpening artefacts in DeNoise AI compared to Sharpen AI which surprised me.

Cheers

Dennis

DeNoise AI Version

Here is the Raw SOC version with no processing - just open in PS CC, Crop full res section at 1200x1200 and save as JPG.

Cheers

Dennis

Raw SOC

nardes wrote in post #18956812
I took a Raw SOC image of a Galah at full resolution and cropped it to 1200x1200, then processed it with the following Topaz Labs Plug Ins at their default settings:

Denoise AI
Sharpen AI

You can see some differences at the pixel peeping level on my screen and I am not sure how this will translate to the saved JPGs as viewed here. One quite noticeable difference is that DeNoise AI has removed the fine, granular detail in the eye of the Galah, whereas Sharpen AI has managed it better.

Viewing the originals, it looks like the fine feather details show a greater degree of sharpening artefacts in DeNoise AI compared to Sharpen AI which surprised me.

Cheers

Dennis

That's what I was seeing as well, that it was easier to preserve detail using Sharpen AI first.

If you look at the red area around the bird's pupil there is more "texture detail" in the Sharpen AI version. Can see it without changing the view depth, just looking at it the way it's rendered on my monitor.