That must be it, I have just moved over 1500 large tiffs to my NAS and to a external drive without a problem from my 2019 Mac Mini also on Catalina.

First glance gives me the name Contax !
My mate had a 1939 model while I had a Leica IIIf (1937?).
Results? in the darkroom and in the final prints you could not pick which was which. The wallet was the final arbitrator.
Sold my Last Leica R8 in August and went Canon RP due to lighter weight. Still kept my Folding Voigtlander RF from 1952 even if It only gets used a few times a year, 120 -8 shots makes it a real luxury exercise!

Just remember that USA Nikon are import models to the rest of the world!!
Currently Nikon Australia gives a 5 year warrantee on a lot of models, do Nikon USA? They are all built in the same place so quality should be the same. The fact that USA believes there is a difference shows lack of confidence in the total Nikon product line. Our Consumer affairs would have a lot to say about that!
A lot of our grey imports seem to come from the U.S or Japan. Nikon's are used all over threworld, why would they bother to make inferior products for some markets. Sounds like the rely on some people being gullible!

btw Canon do make models just for the US - the Rebel Range.

a long time Nikon user with equipment purchased in Australia, Japan and the U.K. all work as expected and have proved reliable and top quality.
PS All the Nikon Medical equipment is made in the same place and of course it is all imported.

Stay safe and wear a mask to protect yourself and all your loved ones.

That might be true in the U.S.A but it was 2019 in Australia. I bought it BUT very limited use for my requirements. Ended up continuing to use FastStone and Affinity Photo - Firestone I gave them A$25 and affinity was about $70 .
Affinity includes minor update for free an a cheap upgrade for major releases.Both highly recommended, I shoot Nikon Raw

Neither work if you are in the bush where there is no internet and if there is you have power (or lack of) problems.

In Australia the government is panicking as there have been over 100 new infections over the last week, mainly due to Staff not enforcing separation at Quarantine hotel.
Victoria has already had 105 deaths BUT good news is number of deaths from Flu hast dropped by 300 this year due to safe distance rules!

First heard that it was a fireman on a Steam Loco and Driver (Engineer) in the bush in Australia. About 1967 I think.
They change the names to participants to to protect the guilty!

Interestingly only one individual called it 'Chinese virus' and he failed to handle it well.
Maybe trying to divert attention from his failing - that could explain it!

I have a similar problem but only on the latest Windows 10 on my 2019 Lenovo Laptop. Works OK on my Mac Mini 2019.
May be a timing problem, the windows is a lot slower. Both computers have lots of memory and are uptodate with software.

Tied to send same photo 3 times and different amounts of the jpg sent each time. That would point to a timeout problem. Tried two ISP's same results and with NEF files.

?? I give up, will just use the Mac when I get home.

Not with NEF , ORF or Pentax. The DNG is simular to Tiff in size. DNG is not a universal standard, it may be an Adobe standard. Tiff is the only 'universal' standard and has been for decades.
I converted all my TAGA files back in the early 90's, they were considered very large at over 2 Mb each but the quality was the best available at that time. Ran the camera on a NEC APC IV Powermate, The TAGA card cost over $4000 and took about 20 seconds to process each image. It had seperate cables for Red, Green and Blue so only a few early cameras would work. I used a JVC movie camera modified to capture single frames.
Just looked for an example and found I cannot read the CD! The Kodak one with the 100 year life warrentee!
Now need to check all my early CD's and hope this is a once off!
Every backup system is forever - NOT

At least I am 40 km from East Gippsland bush fires but the smoke means visability down to 1km or less

My problem is a lousy internet connection and it needs to be connected on a regular basis. Took 4 hours to download LR and PS and neither will work reliably. Luckily did not ditch my 2010 Mac Mine with a CS5 which is now my Photo computer. Must get around to cancelling my Adobe Account as it is veryually useless. Now use Affinity on my new Win10 and 2018 Mac Mini and it seems to work well. Old Mini has an external 3TB hard disk which I can also use on new computers

Somehow lost the .jpg on one file.
Will try updateing

Fathers Day in Australia so dad is getting mum some fancy stones.
Black Swan (Cygnus atratus) showing of his long neck to pick up a red stone which he took back to the nest.
His partner has 2 eggs and there was a broken one two metres away, Pacific Gulls like Swan Eggs!

Problem with download - second link downloads first photo (Long Stretch). Third link downloads swan with eggs (Cygnus atratus.jpg). Did something silly but what??

Attached file:
(Download)


(Download)


(Download)

Sorry but LR6 will not always work on older Macs - will not on my Mac Pro 2009.
The subscription system only works on very recent equipment - Not even 5 year old machine! Also problem if you have a poor internet connection.

I just bought a new Mac Mini i5 and use it with my 27" monitor from my old i7 PC. It is faster but more important in MUCH more stable. It will not do random updates, boot much faster and has more software with it. Only thing is it's SSD is only 256GB as opposed to the Windows machine's 512GB SSD but the Mac SSD is faster. Have just purchased a 1 TB USB 3.2 add on disk and that solved that problem. It cost me (including bigger disk) about $300 more than I paid for my i7 2 years ago so I am more than happy.
The i7 was intended to replace a 2006 Mac Pro but never quite did. Still have old Mac Pro as it is too good to throw away and use it as a backup machine (cost me $280 for a 4GB hard disk a couple of years ago as original 250Gb was too small). Cannot understand why Apple consider 256GB is adequate 13 years later!