So the excitement over the past week has been the new Adobe Camera Raw 13.2 feature touting a quadrupling of your picture resolution using AI. Aptly called Super Resolution, I put it through its paces to see if it actually works on many of my photos of birds that were taken from a long distance back and needing a fair bit of cropping.
There were a lot of mis-steps in the road to discovery, so I will guide you along so as not to repeat the mistakes I've made along the way. That said, here are the step-by-step instructions:
Step 1: Open your RAW file (Nikon NEF, Canon CRW, Sony ARW, etc) using the latest Adobe Photoshop 2021 (release 22.3) and the updated Adobe Camera Raw (ACR) 13.2. Alas ACR 13.2 can only be installed if you have this new Photoshop version.
Step 2: Right-click on any part of the image, select the Enhance function from the pop-up menu (See picture above). You will now see the Enhance Preview dialog box similar to the picture below:
By clicking and holding on to the left button on this enlarged image, you can toggle between the Enhanced image and the Unenhanced image (see below). That way you can see the changes made by the AI-based Super Resolution function.
You can immediately see the changes that will be made by this Super Resolution (SR) feature. Firstly you will notice that it added an amount of digital noise. This is one of the "benefits" of SR. After all, remember GIGO (Garbage In Garbage Out)? You cannot get something out of nothing and so if your image is noisy to start off with, you will end up with artifacting similar to the one above. But nevertheless, there are some noticeable gains - edges are more defined and overall, the image looks sharper.
You can press the [Enhance] button here and the whole image will have a doubling of the horizontal and vertical pixel sizes. As I only want just a small section of the picture to be enhanced, I press [Cancel] here and proceed to Step 3.
Step 3: To zoom in on the image, go back to the main ACR screen and use the crop tool to select just the section of the image that you want and then apply the SR enhancement.
Step 4. You will now see two thumbnails of the cropped image at the filmstrip below the image. (See picture below). If you do not see this filmstrip, just press the [ / ] button on your keyboard. Now comes the important step - you must select the second image as this is the one that has the enhancement.
You now have an image that is twice the resolution horizontally and vertically. This is just perfect if you want to print the image as you now have a file that is four times bigger.
Further experimentations with this SR-enhanced image revealed some interesting facts. Firstly, if you think you can further enhance the image using Topaz Denoise AI or Topaz Sharpen AI, you can just forget about it. I came to that conclusion after testing many files. In fact Topaz just made a whole mess out of the images and I removed it from my workflow completely. Here is a sample using Topaz Denoise AI.
So back to the original question - is there a benefit in all of the Super Resolution? Well yes, if you are wanting to print an enlargement from a file with not enough resolution to begin with.
As for increased sharpness, as I discarded the use of Topaz, I experimented with the built-in Details function of ACR and found that I can increase the sharpness further with no visible penalties.
Finally for an orange-to-orange comparison, I reduced back to the original size using Bicubic Sharper (reduction).
The result speaks for itself. Have a look and tell me if it is all worth the effort!
There are some noticeable sharpness that can be seen - especially to the ants (yes there are ants on the branches!) and the feathers of this Common Kingfisher.
To the Pixel Peepers out there, do let me know what you think and whether is it worth all that work. As always, I welcome any comments - either positive or negative. We all learn by sharing.
Update: 19th March 2021:
So the question that was raised was whether there are any benefits to be gained in running the SR enhancement over previous enhanced image over and over many times. Well, the answer is - No! I experimented with many images, stopped doing it four times and checked the results. There just was no noticeable benefit whichever way you want to review the image - either blowing up the original 4 times or reducing the 4x enhanced image back to its original size. So folks, don't waste your time. It may give you some benefits if you are dealing with very, very low resolution files like 500x500pixels, but for my birding photos shot using the Sony A7Riv, no! Full stop!
I have been using my set-up for taking photos of birds for more than a year now. The configuration consists of my trusty Sony A7Riv with the FE 200- 600mm f/5.6-6.3 G OSS lens. Of late, I wanted to test the lowest shutter speed that I can set when taking birds that are perched.
An opportunity came up when a juvenile buffy fish owl clambered down to a low perch on its maiden flight. The sun was almost overhead and lit up parts of the bird just enough for me to test this combo. This was not the ideal condition, but then again when you are shooting wild-life, you take what mother nature dishes out to you. It was breezy, with leaves swaying and branches moving. The juvenile was no help as it was moving erratically and observing the surroundings.
The camera was mounted on a tripod (not the steadiest) and shot by pressing on the shutter release. It would have been better if a cable release or the RMT-P1BT were to be deployed, but again many situations just demand your immediate attention. The OSS setting was ON and set to #2. I found that turning it on or off makes no difference when using a tripod.
I decided to turn the camera to portrait mode and switched to APSC mode (giving a crop factor of 1.5x at about 26MP). To get even closer, I zoomed the lens in to about 750mm. In total, the effective zoom setting was around 1135mm.
I then started with 1/15th sec. at f/16 in order to hit the lowest ISO setting of 100 and then moved my way up all the way to 1/100th sec. All the photos here are JPEGS (set to fine mode) straight out of the camera without any enhancements by any software. They are cropped to 640x480 to have a zoomed-up enlargement.
As you can see from the image above, at 1/50th sec. the results were very good indeed. For me this shutter is usable in the worst-case scenario where there is not enough light. However the probability of getting a good image is about 1 in 5, so it is still a hit or miss.
At 1/60th sec, my chances of getting a sharp enough picture got much better, with 1 out of 2-3 images acceptably sharp. Still I am only at ISO400, so I decided to stretch it a bit more.
At 1/100th sec, I was getting good odds in the number of sharp photographs that are keepers. The ISO noise of the 61MP Sony A7Riv is beginning to show, but is still very acceptable. If needed I can then run Topaz Denoise AI to completely eliminate the slight graininess.
Interestingly, this is also a good test of the amount of digital noise at the various ISO settings. At ISO640, the image is more than acceptable, and I was able to go as high as ISO 6400 and still maintain a respectable image quality on the Sony A7Riv. But alas, that is about the upper limit of my tolerance, and in the worse case scenario with really poor lighting conditions, ISO8000 is about the max that I will go.
Do try you own shutter speed tests, that way you know the limits of your camera and lens combination. Let me know what you think and I always welcome all your feedback!