I want to apply different presets to a single photo to compare the different looks. I will likely do some basic retouching with the Spot Removal Tool, adjust exposure, and crop before trying the presets. After doing these basic adjustments, what is the best way to apply different presets for comparison? Virtual copies? Snapshots? OR something different?
If you want to see them side-by-side you need to make virtual copies.
If not, applying a preset, remove it with Ctrl+Z and then applying the next, and so on ...would be an easy but fast way. For a one click switch use the snapshots.
applying a preset, remove it with Ctrl+Z and then applying the next, and so on ...would be an easy but fast way.
To build on this, it's very important to do Ctrl/Cmd + Z (undo) after trying a preset. Otherwise, the settings of the presets accumulate. Many people don't seem to realize this, and they freely click from preset to preset without undoing each, producing very unpredictable results.
Also, you could try my Any Preset plugin, which does allow you to freely click (or cursor) from preset to preset without needing to undo. It provides a virtual-copy button to make it very fast to save away candidates for side-by-side comparison.
How are you able to click on different presets without it applying the previous settings to the image? What if you want to stack presets?
I'm not precisely sure what you mean by "stack", but here is how presets work: When you click on a preset, it applies the develop settings stored in that preset to the photo, overwriting the previous settings. Note that presets often / usually contain only some of all possible settings.
For example, consider these two presets A and B:
A: Exposure = +1, Contrast = -10
B: Exposure = 0, Highlights = +20
If you apply A to a photo, then Exposure will be changed to +1, Contrast to -10, and all other develop settings of the photo are left unchanged.
If you then apply B to the photo, Exposure will be changed to 0, Highlights to +20, and all other develop settings left unchanged (in particular, Contrast will still be -10).
So it matters what order you apply presets. And it also matters which develop settings are set by the preset. This can be hard to tell in LR, since there's no user interface that shows you the settings directly. For example, the only way to know whether B sets Exposure to 0 is by changing the Exposure slider to something other than 0 and then applying the preset.
You can edit the preset in a text editor to see its settings -- right click the preset in the Presets panel and do Show In Finder / Explorer. Then open .lrtemplate file in your favorite text editor. (The Any Preset plugin shows you the settings directly.)
Many of the changes I would like to make will be subtle, so I think side-by-side comparisons would be helpful. I also might end up stacking presets, and making changes with the sliders after applying the same presets, so side-by-side would be great. Should I just go with virtual copies in this case? Command+Z and trying a different preset will not work for me. I have never used snapshots so I am not fully aware of how they work.
To eliminate most presets from your choices you can hover the cursor over the see the temporary changes in the navigator. It is kind of small you it gives you an idea of what the preset will do. You can drag down through a list of preset quickly. Just don't click