Yesterday, I had this topic happen to me. I received my dream lap delivered. HP Pavilion 15.6", 2TB storage, 32 GB RAM, AMD Ryzen 7,touchscreen, backlit keyboard. I was finally able to utilize the latest versions of PS and LRC. It was screaming fast. I transferred over 43k photos from 2 external SSDs to my computer in less than 2 hours. All was right with the world! HP suggested I update my BIOS. I figured with everything else being updated (Win 11 Pro, Creative Cloud etc.), why not? 10 minutes later, my laptop was a paper weight. Not only that, I had formatted the 2 ext SSDs to backup the laptop. Luckily, I discovered a third ext SSD with the majority of my photos on it. Saved by the 3rd backup!!!

Hi Urnst. I've been watching this discussion. A lot of what has been said is mostly true, but a couple of errors persist, and the discussion does not explain the reality of what is going on, nor does it explain how to understand why it matters.

It is important to understand that diffraction is a phenomenon caused by edges in an optical system. All lenses have edges bounding the images. Most of the time, this edge is the edge of the iris blades. The only exception usually occurs when the aperture is fully open.

So we have these diffraction effects, which are confined to the area near the "edge" that creates them. At wide apertures, a very high percentage of the image is formed by light that has not passed through the diffraction zone. As the lens is stopped down, the proportion of light that passed through the distortion zone grows. At tiny apertures, the proportion of light which has been affected is highest.

Is this proportion enough to make a visible difference? Maybe, maybe not. Depends on how small that aperture is. Depends on whether the lens is intrinsically good enough for the effect to make anoticeable difference. Depends on whether the skill and technique of the photographer is good enough not to introduce even bigger problems. Depends on whether the lens elements are clean enough that they are not introducing even bigger problems. May depend on a lot of other things, as well.

In my experience, more often than not, diffraction is just a topic that lets people have a discussion involving lots of big words. Sometimes it matters. Sometimes it's just a waste of time and energy. You have to figure out which. It's probably never worth getting your blood pressure elevated.

Please see my earlier comment. Of course we all agree how diffraction is created, but the actual mechanism which causes diffraction effects in photography is multiple pixels being covered by the Airy disc, and the smaller the pixels, the more likely that multiple pixels will be covered. For equivalent resolution, smaller sensors have smaller pixels, hence more pixels covered by the same size Airy disc and greater diffraction effects. The article I referenced from Cambridge in Color explains it in simple terms and includes a calculator that demonstrates what I said above. Please read that article and tell me why you disagree.

Cambridge in Color has a tool to allow you to view an image with different apertures: https://www.cambridgeincolour.com/tutorials/diffraction-photography.htm

Or better yet, use a good photo resolution target and take images from f8 to f22 and compare. It’s easier with a target than a complex scene. I’ve done it and can see the difference, so I try to stay at f11 or larger on ff and f8 on crop, but if a larger DOF is essential to your image and no other way to get it (such as focus stacking), then you just have to live with it.

Lots of opinions very little to corroborate them...
While I have reservations that that there are enough technical savvy photographers on UHH to actually appreciate what Thom brings to the table on his extensive analysis which he has continuously update over the past decade.

Thom was a senior editor for a very widely read and revered Photo Magazing for many years.
To this end I would suggest you bookmark his dissertation since it is extensive and actually enumerates which of Nikon's VR iterations function on a myriad of their Nikkors.

What Thom shares here is that there are not any "rules" or "best practices" for VR but rather a kaleidoscope of parameters to keep in mind each of which may only be germane to a small subset of VR optics. Nikon continously advances the technology as it moves forward. This has resulted in newer Nikkors rising the performance bar...

The most scary takeaway? Since i'm certain few will actually study Thom's analysis.
If you disconnect a VR optic while the VR system is still spining down you have placed you lens in serious harms way... i.e. yes you can trash a VR lens by removing it too quickly from your camera...

From experience I've noticed some high end Sigma's optics are slow to "park" there floating elements. Sigma actually cautions that it's OS takes a second or so to spin down... And since Sigma was sued by Nikon for copyright infringement on it's VR I'm a believer here. I've always allowed my 50-150mm f/2.8 HMS OS IF Sigma to spin down prior to removing it... enough said

Here's Thom's wisdom on VR (which I've study many times over the years (he updates it constantly))
https://www.dslrbodies.com/lenses/lens-articles/lens-technique/all-about-nikon-vr.html
Your welcome...

This morning brought an amusing set of posts pertaining to what is on my list to work through. I just replaced a 10 year old PC that couldn’t be dragged any further into the current world. I always kept the OS updated, replaced all of the storage with larger SATA SSD drives and had 16GB memory from the get go. BUT the USB 3.0 hardware failed, the GPU never was compatible with where Adobe and others are and the mother board couldn’t accommodate one that was capable. So I had Puget Systems build one to my specifications which will likely out live me. And I sprung for the Topaz AI triad.

After a couple of rough months in my real world in am in the process of carefully moving to the new machine this time with tedious discipline. Almost done and starting to look at integrating the Topaz suite with the Adobe centric workflow.

The basic fact is a raw file is raw. Only a camera can create a raw file. Once a raw file is “cooked” it cannot be saved as a raw file. You can’t uncook an egg. Your best bet in to create a 16 bit TIFF file. You can’t recover the recorded data lost in adjusting the white balance, color space, sharpening, and noise reduction to name a few. That is why you tell LrC to the file type and color space to create and send to Ps when you “edit in Photoshop” and subsequently Ps returns either a TIFF or PSD… to your LrC folders and catalog. (I omit editing edit as a smart object because I have never tried that.) So what workflow do you follow? Presumably Topaz AI apps do a better job if fed a raw file but then must cook their processing into a limited editable file. Is DNG really a solution to this conundrum? Help! 80 year old brain is smoking!

I think you'll find that the large file is created after you call the external editor (Topaz) but before you start working in Topaz. In other words it's Lightroom that's creating the large file and it's doing that as soon as you call the external editor. Presumably the reason it doesn't do that with Ps is that they have another protocol because they are both Adobe products. You'll probably find that Lr produces the intermediate file when it calls any other external editor other than an Adobe product.

It's a simple procedure to get rid of the intermediate file. Just make sure you're not selecting the original file for deletion. The original file and its Lr adjustments (if any) will still be there in Lr. Checking the film strip along the bottom is the simplest way to keep an eye on what's happening. That's the first place you'll see the intermediate file when it's created. As far as I know, the intermediate file will always be a TIFF.