I am failry new to Lightroom and I am still learning this one hell of a software collosus.
I want to start using smart previews since my mac has only 128gb SSD available and I have nice and clean 500gb SSD external drive for RAWs. However, those smart previews as for now only multiplies my questions, here are three most important one:
1. Let's assume I'll do the import, I will build smart previews for whole import then unplug my external drive. Next step is - naturally - to reject some photos and I'm doing this while my ex-drive is still unplugged. I am deleting my smart preview from library but will LR delete my photo from my external drive when I'll plug it in?
2. I have my nice library with smart previews and original on my external drive then unfortunately it dies completely but luckily for me I have a second external drive with whole backup of all the photos. Will I be able to reconnect those smart previews to second ex-drive?
3. Sooner or later I'll be changing my mac to something newer. What about exporting LR catalogue? Is it the same as withouth smart previews or some additional steps must be taken into consideration?
Thank you all in advance for clearing those things up for me!
Why do you want to use Smart Previews in the first place? Simply so you can unplug the external drive? If so, don't create smart previews and don't unplug the external drive. If you are traveling, and so you have to travel without the external drive ... well ... then you do have a problem, and the size of your 128gb SSD is the problem. There's not much you can do if the external drive is unplugged and you have limited space on your internal SSD.
You can selectively delete Smart Previews if you are sure you won't need them on your trip. In LightrooM Classic, select the photos for which you no longer want Smart Previews, and then Library->Previews->Discard Smart Previews.
Adding ... don't make a mistake and delete the wrong Smart Previews before your trip, because without the originals on the external drive, because then you can't create Smart Previews of those photos without the originals on the external drive. And once you get back home, remember to re-create the Smart Previews for those photos ...
If you are travelling and must have access to ALL (that's 100%, every single one) of your photos, you might consider either getting a bigger internal drive, or finding a way to take the external with you, or using the cloud-based Lightroom where you can access all of your photos via the cloud.
First off, it's very important to have as much empty space on your hard drive as is reasonable. I have a 1TB SSD drive on my Mac and it almost never goes about 500 GB full. This "empty space" is requried for efficient room for LR, PS, and other applications to work in. When you fill up your computer's HD, it makes it harder for the applications to be efficient.
If you're concerned about filling up a 128 GB drive, than you do not have that many images (yet)! But you will and that's the issue.
Here's what I do: I have a 4TB drive that holds all of my images and most of my important documents. HOWEVER, there's an adage that says: "There are two kinds of computer users: those who've had a hard drive crash and those who've not had a hard drive crash yet." In other words, putting things as valuable as your images and important documents is, well, risky. So, I have a 2nd 4TB drive that I back up the first drive at least once a week or just after an import of images (or documents) that matter.
For organizational purposes I have the images (in sub-folders) and the Catalog all in one folder on the external drive. This means that it's easy to find it because it's all together.
But a 2nd drive can be burnt in a house fire as with the first. So I also use the Cloud service BackBlaze. So, I have my files backed up in three places. (Oh yeah, I also take advantage of Apple's Time Machine but that only backs up files on the main computer.)
Travel: I do not own a laptop but my wife does. When we travel, I comandear it. I create a brand new Catalog for just that trip. When I take a day's shoot, I ingest it into the Lightroom on her computer (she never uses it, it's my 2nd copy). After I process as many images as I can for that day, I back everything up on an external travel drive. This is done dayly.
When I get home I take the external drive which has the LRC Catalog and import the images and data from that Catalog into my main, primary Catalog.
This is a bit tedious to do all of this but it really takes no extra time and surely is less time than the grief that I'd have if all of my images were lost.
If you need any further details on what/how I do things, just ask.
A few subtleties that haven't been answered yet.
1. This scenario ONLY works if you store the catalog and the previews on the internal drive. If the catalog is on the external, the smart previews will be right next to it and when you unplug the external, neither the catalog nor the smart previews will be available. So if you are storing the catalog on the external as your second question implies and as I would expect with the tiny internal SSD in the mix, you can't do anything. If you are able to put the catalog on the internal SSD including the previews but store the raw files on the external than yeah, generating smart previews will allow you to edit images. Note that you ONLY need smart previews in that case if you want to be able to go into Develop. If you just do culling and keywording you don't need smart previews. Lastly if you are working like this, deleting the image from Lightroom's catalog will then NOT delete it from the external when you reconnect it. You would have to manually do that if that's what you want to accomplish
2. Assuming you have your catalog on the internal SSD in this scenario, you won't have to do that as the smart previews will be on the internal SSD next to the catalog file. You will be able to connect the raw original files on your backup to the catalog.
3. There is no difference. Just copy over the catalog and associated previews and everything will work. No need to export. You might have to update the location on the originals on the new computer but there really is no need to export anything.
Again smart previews have very limited use. They are only used if you go into Develop and the original image is offline. Nowhere else are smart previews used for anything. In general they are a waste of space and time for most workflows. There is rarely a point to them except if you travel with a laptop and don't have access to the originals. For your workflow, I would just get a 1TB SSD that plugs into your computer (they're cheap and tiny) and double sided tape it to the lid of the computer and keep it plugged in.
Thank you for explaining everything nice and clean.
I stambled upon smart previews when reading about Lightroom performance. So let's say I won't use them but I will still be using external ssd drive (on usb-c) for keeping photos, there won't be any hiccups?
Also the last question - the important one. Should I just keep my photos on SSD but LR catalog on internal drive or should I create LR catalog on external drive? Is there any difference?
If you won't use the Smart Previews, don't create them. Get rid of them. Only create them if you are having performance problems.
Catalog should go on the fastest disk, which is usually the internal HD/SSD. Photos should go on an external HD, no need to spend extra money to put them on an external SSD as you will never notice the speed difference.
One of the good AND bad things about LRC is that it doesn't care where your images are located or where the Catalog is located.
The good is that it gives you tremendous flexibility but with that tremendous fexibility power comes tremendous fexibility responsibility. YOU have to know that you cannot moved LR items (images, xmp files, Catalogs, etc. in the Finder or Explorer, you HAVE to move them within the confines of LRC.
LRC is a database and when things are moved outside of LRC, LRC doesn't know squat about that such a movement and that will confuse it.
The good news is that you're just starting to work with LRC and you can make mistakes and recover relatively easily. DJ's comments on placing the Catalog are absolutely correct. For other reasons (mentioned) I'm willing to lose a few miliseconds to have my Catalog and files all on the external drive. Do whichever way that seems the best to you (or something alltogether different). LRC will not care.
I am currently setting up things thanks to your advices. Thanks again!
1. I was also looking for answer in this particular topic. Quick and elegant resolution for me is Reject filter. Hit that X while browsing your catalog with smart previews and when you are back online with your original RAWs at home/studio, simply filter Rejected photos, delete them then safely, and you are done. Cheers