Adobe’s record when it comes to designing software is certainly a mixed bag, sometimes we get great new features, and sometimes those features come rolling along half baked. And that’s very much the case when it comes to the new development defaults in Lightroom Classic 9.2.

I’ve previously written about using Lightroom’s development defaults as a way to save your sharpening and noise reduction settings on a per ISO basis so that they’re automatically applied to your images when you import them. In my experience, this is a tremendously useful mechanism for getting most of the way to a well optimized image right out of the image dialog.

However, in the past there have been a few major shortcomings with this approach. To start with, you had to create a default for every ISO you used — which usually meant every ISO your camera could shoot at. On modern cameras with ISO ranges from say 50 to 102,000 in 1/3 stop increments this made for a lot of tedious work. This was especially true when many of the settings were the same for multiple ISOs, but you still had to create presets for them anyway.

The second problem is that some cameras, mainly Nikons in my experience, when shooting in auto ISO, don’t always use the standard 1/3 stop steps. I’ve run across all kinds of crazy ISOs from Nikon bodies that there simply wasn’t any way to get to manually. And this of course, means that there was no way to setup a default for that ISO.

Which brings me to the new development presets in Lightroom Classic 9.2. Adobe has chosen to abandon the old mechanism entirely. The old way of assigning presets is gone, the old preset XMP files are gone, and unfortunately, so are your old presets if you created any.

On the flip side, the new presets are somewhat better exposed, and certainly more easily portable between computers as they’re now simply xmp files.

Additionally, Adobe has extended the format to support ISO dependent settings. And, the best part of which, is that Lightroom will now interpolate between ISOs that aren’t specifically indicated. You can now have a preset for ISO 400, and another for ISO 3200, and all the intervening ISOs, including the oddball Nikon auto-ISO ones, will be smoothly interpolated between the two end points.

That said, I did strongly imply that there’s a catch to this, and there is. Adobe rolled out this feature without providing a way through Lightroom itself to create these ISO dependent preset files — you have to do this manually in a text editor.

To make matters worse, while they provide some samples they don’t provide complete documentation on how the presets work. And this is what I’ve spent the last hour working on trying to figure out.

So this is what I’ve discovered so far.

First, you’ll notice that there are essentially two parts to the preset’s xmp file. First there are crs: attributes in the <rdf:description tag at the start of the file.

Any setting put in this part of the file will be used as the default value for all ISOs, or when it’s not otherwise specified a <rdf:li tag in the <crs:ISODependent> section at the bottom of the file. More importantly, these defaults are also used when Lightroom interpolates between ISOs where an intermediate ISO omits attribute that was defined in the surrounding two.

For example, if you have ISO dependent settings for ISO 400, 1600, and 6400 per the following abridged example.

<rdf:description ...
  	crs:sharpness="20">
  	...
	<crs:ISODependent>
    	<rdf:Seq>
        	<rdf:li
            	crs:ISO="400"
	            crs:sharpness="50">
    	    <rdf:li
        	    crs:ISO="1600"
            	crs:LuminanceSmoothing="50">
            <rdf:li
                crs:ISO="3200"
                crs:LuminanceSmoothing="60">
	        <rdf:li
    	        crs:ISO="6400"
        	    crs:sharpness="30">
    	</rdf:Seq>
	</crs:ISODependent>

In this example, you might expect sharpness to interpolate smoothly between 50 at ISO 400, and 30 at ISO 6400. That is, you might expect ISO 1600 to have a sharpness of 40.

However, what I’ve found in my testing is that since ISO 1600 and 3200 don’t have a sharpness value specified, Lightroom will assume that they use the default sharpness of 20.

So instead of the sharpening going from 50 at ISO 400 and below, to 40 at ISO 1600, to 35 at ISO 3200, and then to 30 at ISO 6400. It will go from 50 at ISO 400 and below, to 20 at ISO 1600 to ISO 3200, then back up to 30 by ISO 6400.

Though keep in mind intermediate values will still be interpolated. So ISO 800 would have a sharpness value of 35, not the expected 45.

That said, being able to interpolate between ISOs does make creating presets somewhat simpler — well aside from having to edit them yourself, as it allows skipping most intermediate ISOs, and even many full stop ISOs.

I’ve been able to simplify my 5D mark 4 import defaults from having to have 29 individual presets, to only 16 ISO sets in my initial pass at creating an ISO dependent preset. And I’m fairly confident that I can further simplify this by removing some intermediate ISOs that don’t need to be be there.

Unfortunately, Adobe didn’t feel the need to provide a tool to convert users old ISO specific defaults into an ISO dependent defaults, so users that made use of this feature are left to scramble to create new ISO dependent presets to continue their previous workflow.

Overall I can’t complain too much about the change, as I’ve wanted both interpolation between ISOs, and a much easier way to transfer presets between computers and catalogs for a long time now. That said, as ISO dependent presets are a critical part of my camera acclimation and setup process, I’ll be revisiting this in more detail once I’m more comfortable with the new process.