Here’s something that may have slipped by unnoticed. Adobe Lightroom added a new feature recently called Reference View. This new functionality is part of the Develop module and is really useful when you want to edit one photo and you want it to look like another image.
Maybe you are trying to create a preset and want to match the look of another image. Or, maybe you are trying to ensure that white balance is consistent with a set of photos. In either case, it’s great to be able to tack up a static reference photo so that you have a side-by-side view while you edit your image.
Using the Reference View is really very easy. It is a function in the Develop module, although you can get to it from the Library module or the Develop module.
From the Library Module
If you’re in the Library module, you’ll want to set the image that you’d like to use as the reference photo, and then open the image that you want to edit. This second image becomes known as the Active image.
Find the image you want to use as a reference and right click on the image. Then click “Set as Reference Photo”. Next, find the image you want to edit and then click “Open in Reference View”. Lightroom will open the Develop module and have the static reference photo opened on the left and the Active photo open and ready for editing on the right
From the Develop Module
If you already have a photo open for editing in the Develop module, click on the RA button on the toolbar. If there is not a photo showing in the Reference panel, you can drag and drop any image from the Filmstrip. You can also right-click on an image in the Filmstrip, or, from the Library module grid view, and then select “Set As Reference Photo.”
Editing Your Active Image
Once you have your Reference and Active images open in the Develop module, you can use all of the editing tools except one - the crop tool.
Lock Reference View
When you’re done editing and return to the Library Module, Lightroom will clear our the Reference photo. If you want to use the same photo while editing more than one image, then click on the Reference Photo Lock icon in the toolbar while in the Reference view.
Match Pixel For Pixel
If you’re trying to match a photo down to the pixel level, then check out the data under the Histogram. This is really intended for identical images that are being processed differently. Say, for example, you used a plugin to edit the image and you’re trying to match that look in Lightroom.
When the dimensions of the Reference and Active images are the same, the data for the RGB values are displayed under the Histogram with the Reference image data on the left and the Active image data on the right. This information can be very helpful while adjusting tone and color sliders.