Why would smart previews take longer to build from one SD card to another?

[shotbydna]

I am importing two SD cards into lightroom classic and the smart previews take significantly longer - about 1 photo per every 3-4 on other cards - on a certain card. The 2 SD cards I'm using are the same exact model and size and have been used the same amount of time. The cameras shooting to the cards are the same exact model with the same photo settings. The only difference is the amount of photos - the card in question has double the photos. BUT I have tried importing equal test amounts from both cards (1000) and am experiencing the same ordeal. I have tried importing the second SD card (camera shoots RAW to 2 slots simultaneously) from the same camera and the problem persists. Thus, the cause is the camera. Both are Sony a7r4a's. I am curious as to what interaction Lightroom could have with one camera over another to cause this problem. Thank you for your time!

MacOS 14.6.1

LR Classic 13.5.1 

SONY A7RIVa (x2)

[GoldingD]

Double check. are you sure that both cards have RAW files. Some cameras with two slots can have:

• All photos first to slot 1, then Slot 2 (sequential)
• All photos to both slots (backup)
• RAW to slot 1, JPEG to slot 2

Also, be aware that on some cameras, if shooting RAW+ JPEG, with JPEG going to slot 2, in camera pano, any toy filters, any multi frame creating JPEG, and video, may go to slot 2, so slot 2 may have more files. (mind you only the video files will eat lots of space)

[shotbydna]

Appreciate the reply. We are professional photographers of 7 years bringing in over 100k photos a year so we have our method down. Both cards are definitely just RAW files. This problem is somewhat new. 

[DdeGannes]

@shotbydna , You stated "I am importing two SD cards into lightroom classic and the smart previews take significantly longer -"

Please indicate what option do you use on import, Copy, Move, or possibly Add?

[shotbydna]

Copy 

[Jao vdL]

Are you perhaps by accident using "add" instead of copy? If using add, you would be limited by the speed of the sd card and reader. Also, are you sure you need smart previews? Smart previews are only useful if you want to edit your images while they are not online. They offer basically no (or actually negative since you are waiting for them to be generated) speed advantage or other advantage when you have your images actually available on modern machines.

[JohanElzenga]

@Jao vdL You can't use 'Add' when importing from an SD card. That option is dimmed.

@shotbydna When I look at the info in the upper left corner, I get the impression that smart previews are built after the image has been copied to the hard disk, so I have no idea how the SD card could influence the speed of smart preview generation alone. It could of course influence the total import time (copying, generating previews, generating smart previews) if for some reason the read speed of that card is lower than the other cards.

[Jao vdL]

It depends on the reader and the operating system and the type of card. I have definitely seen it offer Add with certain memory cards. Not recently but it is possible and I was assuming perhaps the OP calls any memory card a sd card. It has to do with how the operating system reports the card and that has to do with the driver for the reader. If it is reported as a hard drive instead of removable media, Lightroom Classic will offer the add option.

No clue how this would influence smart preview creation indeed except if the import speed is really low but usually these are done sequentially.

[JohanElzenga]

Yes, the newer CFExpress and CFast cards are seen as removable hard drives, but the OP uses Sony A7R 4a cameras, which do not support these cards yet, so he's definitely talking about SD cards.

[Jao vdL]

You are absolutely right! Should have noticed the camera type. Your idea of compressed vs uncompressed would definitely be a good explanation for the bahavior!

[shotbydna]

Yes I am indeed using a couple of SanDisk SD cards, not CF. Both cameras have exact same settings, including shooting compressed RAW on both. I realize the speed/state of the SD card shouldnt affect the smart previews which are built on locally stored copies after import, so I'm starting to believe it has something to do with the specific camera in question creating corrupt files of some kind. 

[JohanElzenga]

Thus, the cause is the camera.

By @shotbydna

Are you sure this camera is not set to uncompressed raw while the other is set to compressed raw? That would explain it...

[shotbydna]

Indeed both cameras have exact same settings, including shooting compressed RAW on both. 

[GoldingD]

This should be a bit far fetched, but

LrC /Preferences/Presets/ RAW Defaults, not set to a specific cameras serial number perhaps?

[JohanElzenga]

This should be a bit far fetched, but

LrC /Preferences/Presets/ RAW Defaults, not set to a specific cameras serial number perhaps?

By @GoldingD

How would that explain the writing speed difference of smart previews?

[shotbydna]

No nothing set here, its on Adobe Default, override global setting is unchecked. 

[shotbydna]

Just did a bit of an experiment. I took camera A (problem camera) and put the SD cards that normally go with it into camera B (the control variable). After importing a gallery of about 500 photos on each I'm seeing the SD card from camera A exhibiting the smart preview problem, even though it was shot with camera B and even though the files are copied to the local drive before the previews are built. It's the same problem - about 1 preview built for every 4-5 on the other card. This obviously leads me to believe it is the fault of the SD card - which is still strange because the files are local for the building of previews - but I did another experiment where I used the second SD card from each camera and the problem persisted even with Camera A's second card. I can get new SD cards no problem, but now my question is was it the camera that possibly corrupted these cards? Will I be up against the same problem once I slap brand new SDs in camera A? I know there is probably only one way to find out, which I will and shall report back. 

PS. Another strange problem with LRC that may or may not be a clue. Everytime I open my catalog I check for missing files and lately there are always 10. Exactly 10 that were originally sourced from the Lightroom Sync folder inside the catalog folder. I do not import images here, nor do I download images via the cloud. The photos that are missing are not specific to one SD card or the other though. Just thought it was strange for these problems to be coinciding. Eventually I will be getting a new Mac to eliminate the final variable. 

[shotbydna]

Ever since the update the whole catalog has been buggy I've found. I've started a new catalog with a new computer and it seems to be running ok. Problem now is with the syncing, I'm getting 10 pics synced every 20 mins with 700mbps internet speeds. 

Can someone validate my anger with adobe support? Its so bad it makes me feel like I'm living a nightmare when I'm talking to them. Zero help, constant transferring. I've gotten way more support on this forum.