From other posts on the RX10 IV over the months, I think my impression is a common one. I was prepared to be pleased with the camera based on reviews but I was stunned. The camera redefines what is possible. I was shown the camera by another photographer on a recent trip and thought, "Right, I've seen cameras with huge focal ranges but the IQ is pretty pitiful." I only considered it after look at reviews (a lot), bought it, and never looked back. I knew from the beginning I had a game-changer in my hands. I highly recommend the book by Gary Friedman, which I think you said you had ordered. The menus can be intimidating. What he recommends is this: (p 51-52)

"1.3 JUST PICK TWO
During the course of learning this camera, you will find that there are many, many, many (some think too many) ways to do something. This is especially true regarding things like focusing and exposure modes. Keep in mind that the engineers weren’t expecting everyone to use every feature; they designed the camera with so many choices so it can be customized to work the way many different people work. And so, trying to memorize every mode so you can know what to select out in the field is an exercise in futility – it will just distract you and prevent you from thinking about the important stuff (that would be light and composition) while out in the field. Don’t do it.

My advice: Go through all of the choices for each feature described in this book. Then pick TWO techniques for everything and just get good at using those two."

He then goes on to give an example.

I bought the camera from B&H so I could return it if it did not live up to expectations. Within 15 minutes, I had decided that was not going to happen. You might consider a similar strategy.

I like to think I'm not a pollyanna, but I do think that an occasional reminder can tamp down the numbers a bit. Since I had not seen a post like this for a while, I felt it was time. I worried that my post might be as distracting as those I was criticizing, but at least (I like to think) everyone knew what they were getting in for, i.e., knew the issue.

If I look down a list of topics on any particular day, there seem to be several topic titles like, "Should I buy this camera?" So the reader has to click on the topic just to find out what camera is involved and whether s/he has anything to contribute. Or whether the reader might be interested in the answer. With a dozen or two topics each day, this would be a lot of unnecessary clicking if everyone did it. Thankfully, everyone doesn't, but everyone who peruses the topic list has to click on it to discover what it's about. This is a request to be considerate of your fellow Hogs. Take a little time to think how to include a maximum of info in the topic title without using 1000 characters. We owe it to each other.

I know this has been addressed from time to time but the evidence is that it needs to be re-addressed now and then...and again.

Thanks for everyone's responses. It has been very helpful in unexpected ways. I am now considering whether to go back to 3-1/2 floppies, which have a much more welcoming name - brings a beagle to mind - than hard drive or solid state drive.

Seriously, the variety of answers is fascinating. I am rethinking what I do.
The original motivation was the syndicated column, "On Computers," by Bob and Joy Schwabach, possibly the longest-lived column continuously published in the world...it began in the early 1980s. In a recent column Bob Schwabach questioned whether anyone except those collecting movies has any need for terabyte drives. I wrote and described my need - I use a 3 TB primary drive for just photos and it is half full - and suggested that there is a world of serious photographers out there who need drives that large. Although this is not a scientific survey (because the respondents are self-, not randomly-, selected), you have supported my claim. I will report this to the Schwabachs and I guarantee that they will find it just as fascinating as I do, especially the comments about floppies! Looking at you, royden.

I'll start.

3 TB drive, 50% full. Contains all of my photos which are backed up on three drives of equal size.

Agree on comment on jars: a tighter crop. In a shot like this the revel is in the details. In the jars, in the wood grain.

Although I've never tried exactly what you want to do, I am sure that if you have told LR to look for your photos on the backup drive (by clicking on the ? then locating the folder there) and then later mount the primary drive, you will again have to tell LR where your photos are (on the primary drive, this time). Otherwise LR will expect to find them on the backup drive. Each time you do the "locate" thing, you are telling the catalog where to find the photos. You won't corrupt the catalog by doing this but you will have to tell where the photos are if you have moved to a different drive.

I'm sure I would, as I am impressed with the Kolb brothers at Grand Canyon who, among much else, famously took photos of tourists on mules before they descended into the canyon to Plateau Point, then ran five miles down the trail carrying the glass plates to Indian Gardens 3000 ft below for the only fresh water available to them, processed the plates, then ran back up with the plates to arrive before the mules/tourists returned from their day ride. Same thing next day.

Still, Rowell was an accomplished mountain climber as well as photographer and carried his equipment with him on, for me, impossible climbs to show the viewer what climbers see.

Amen, Linda.
In addition to his photos, you had to admire him for carrying all that equipment to all those impossible places.

The instructor has the time and means to get into optimum position and is not traveling all over with luggage and his primes. You will be much better served with one or two zooms. 400 mm might not be used much but there will definitely be times when you need good reach. As you cruise the Mekong there will be many many wonderful scenes on the river and the shore that will be a stretch for 105mm. So I would take the 24-105 and whichever of the two long zooms you prefer.

The economies of Cambodia and Vietnam are starkly different. This difference is apparent in the checkpoint buildings for the two countries at the border, on the left side of the river as you cruise downstream. The Vietnamese one is pretty impressive, the Cambodian one is a shack. Worth a shot for its symbolic value. Before the Khymer Rouge, Cambodia had the most prosperous economy in the region. Pol Pott succeeded in his goal of reducing Cambodia to a medieval level.

It is hard to resist showing up for the sunrise photos of Angkor Wat, but it will be a mob scene so getting a photo without the mob and the phones high on sticks (with their illuminated screens) down front will be pretty impossible. Unless the sunrise is spectacular, equally good photos of the ruins can be got at other times, IMO. Others will probably disagree. My experience is that if someone mentions "sunrise" or "waterfall," people will fall over each other to get there for very ordinary photos of very ordinary scenes. I come from that perspective.

If you cannot read your sd card, it is not necessarily the end of the line. I had this happen several years ago, took it to my local store (Bedford's) and for a pretty paltry sum they recovered all but one or two pics. I assume I could have used the same, or some other, software but did not know what was possible back then. It might be a mistake for this thread to morph into a one- or two-slot camera debate. Things are not that dire.

Agreed. But even better IMO would be a left glove configured for an equine version of Don Meredith's (paraphrased), "There's a horse who thinks his team is No. 1."

Years ago, a photographer, hired by Kodak to go from national park to national park giving slide shows of his work and offering tips on nature photography, gave this tip for flowers: use your hat (eg) to produce a shadow behind the flower, which will highlight the flower. His flower photos were almost always with a shaded background and it was easy to see the visual effect. Since I am bald, I always have a hat and have used his tip many times over the years. A helper is a help sometimes, but if using a tripod, I can usually manage alone. This has the advantage of not having to anticipate a photo op where you might not have a black board along. Or if you're backpacking and left your black board at home.

I started doing this when on a river cruise in Cambodia but we took a bus one day to connect to boats. There were many unbelievable scenes of daily life and such and I was aching to record some of them. Nothing very artsy but life goes on even without the art so I started trying the obvious. I became quite good - or at least better - and was able to capture a family scene or a Buddhist statue or any of a wide variety of small objects just by aiming by instinct and panning at 1/1000 sec and a med aperture so to help the focussing issue, ISO whatever is needed. As time went by, I got to be pretty good and came to feel that I was not wasting my time while on the bus.

Interesting. When I was a kid taking photos with a Baby Brownie, "visually as good as" meant that the prints looked just as good. In our digital age maybe it means something else but I don't think so. The OP asked about IQ of prints so the Friedman excerpt seemed entirely appropriate.

Of course, it's true that "in less light, noise becomes an increasingly serious problem," equally true no matter the camera. It's equally true that, if you don't want to take photos when it's too dark, a FF camera should be fine. For any camera it can become dark enough for unsatisfactory results, depending on one's criteria. The question is whether you are able to manage the noise to your satisfaction. The following suggests that many will be happier with low-light/high-iso pics than they imagine.

Here is a link, https://www.dpreview.com/forums/thread/4221226, to some photos taken at iso 3200-6400 with the rX10M4. The relevant photos are the second set with the fall leaves. You can enlarge them (a lot) to see noise by double-clicking on the photo. Considering the high iso, I think it's impressive.