Your teacher is absolutely right 'Smart Objects' are a far better way of working because edits are non destructive and save vast amounts of time in real world design projects. More specifically we are talking about 'Camera Raw Smart Objects'. Lightroom can export to Photoshop in two ways. 1) as conventional images or 2) as 'Camera Raw Smart Objects' . I'm guessing you already know how to do both export processes, but if not just ask. Once you have your camera raw smart object in Photoshop you can do virtually anything you can with a regular background layer. Yes 32 bit images can cause problems and some of the very oldest filters may not work-but there are workarounds for that. What you get with smart objects is access to smart filters that can be applied in series and not damage a single pixel of the original image-everything is completely reversible. The downside to smart objects is they consume system resources and in particular memory, but most modern computers handle them with no problem at all. With a camera raw smart object in Photoshop all you need to do to edit the original image is double click the smart object and it will open up in camera raw and you can process whatever edit you want, save and the smart object updates automatically in Photoshop. All in all everyone should be working with smart objects but they are perceived to be hard, maybe true at first, but with 30 minutes of practice the benefits are obvious.
Smart Object editing is the way to go in most cases. But they've only been around for a few years so a lot of content on the web about editing didn't include them. Heck, even newer content doesn't include them. In commercial "real world" environments, it's definitely the best way to cover yourself for future edit requests.
Learn to edit with things like Adjustment Layers, New Blank Layers, etc, so that you are stacking over the original image. Many tools that may seem limited, such as a stamp tool, just need its options changed to say "Sample All Layers" rather than the "Current Layer" default.
Hope that helps.
The downside to smart objects is they consume system resources and in particular memory, but most modern computers handle them with no problem at all.
Chris Cox (lead developer of Photoshop team, now retired) at the time mentioned that smart object are actually meant to save system resources and processing power, and keep Photoshop from responding (too) slow. The contents inside a smart object is pre-rendered, and that speeds up things.
But you are correct that placing a RAW file in a smart object eats up more memory than a flattened version of the same image data. It depends on the image data in that smart object. If the SO merely is created to transform a layer non-destructively, then there isn't that much difference in regards to memory use.
If, however, a complex Illustrator-made illustration of 50mb is placed in a Photoshop smart object, then yes: a flattened layer will take up much less memory space.
I suppose we ought to differentiate between CPU time taken and memory taken.
It would be good to mention some of the disadvantages of smart objects here as well for a complete picture:
- SOs open in a new window and cannot be edited in-place, which is rather cumbersome and awkward at times;
- Photoshop doesn't provide a default setting to open SOs side by side with the master document;
- changing the content in a SO does not cascade in real-time or without saving to the master document;
- the fact that a SO is required at all to accomplish non-destructive layer transformations is, at the very least, inconvenient, and a workflow-breaker at its worst.
yes all true. I possibly play up the advantages to encourage OPs to try to learn Sos , but there is certainly scope for improvements in usability.
There is a difference in opening a file as a smart object from lighroom and creating one in Photoshop. If you open a file from Lightroom or Camera Raw, when you double click on it to edit it, it goes back to Camera Raw for editing. A file that has a background layer - or other layer - converted to a smart object will just open a new window in Photoshop for regular editing.