This is the second in a series of articles abut passing images between Lightroom, Photoshop and various plugins. The other posts include:

• Are You Wasting Dynamic Range?
• The Lightroom “Edit in…” Problem
• RAW File Processing: Photomatix Pro vs. ACR/Lightroom
• HDR Tools Comparison
• Aligning Images for HDR

[See Update at the end of the post. 4:20pm PST on 1/10/12.]

Yesterday I posted the first in this series of articles (Are You Wasting Dynamic Range?) about problems passing images between Lightroom and Photoshop, plugins, etc. Today I want to look at just one such situation, the use of the Edit in… menu option in Lightroom 3. An hour ago I saw the announcement of Lightroom 4 beta. I wonder if this is something Adobe would consider fixing for version 4.

The Challenge

We start with the image below of the Golden Gate Bridge at night. Not only is the image generally overexposed, the highlights are completely blown out. Can we rescue this image? It’s easy to darken it overall, but what about those highlights?

Luckily it was shot in RAW so there’s a lot of data in the highlights and (to a lesser extent) the shadows that we can’t see in this uncorrected version. Just to be clear, what you see below is not a RAW image. There’s no way to display a RAW image in a browser or on your screen. The dynamic range of the image is just too great. Instead, what you see here is a JPEG derived from the RAW file using the default Lightroom settings. [Note: You can click on any image to see a larger version.]

Correcting in Lightroom’s Develop Module

Below is an example of what we can do in Lightroom (or pretty much any other RAW file processing application) to recover the highlights and reduce the overall exposure. (For the curious, the settings are Exposure=-2.55, Recovery=65.) Additional corrections could certainly be made, but this illustrates what we’re trying to show. We’ve recovered a lot of detail in the highlights in both the moon’s reflection on the water and the city lights in the distance.

Passing the Image to Photoshop

Now suppose you use Lightroom to organize your images, but you want to make your corrections in Photoshop rather than in Lightroom’s Develop module. Select Edit in…Photoshop CS5 from the Photo menu or right/ctrl-click on the image in the grid. Photoshop starts up and shows you pretty much the same thing as the first image at the top of this post.

But if you now try to recover the highlights, the image below is pretty much the best you can get. (Exposure adjustment layer with Exposure=0.38, Gamma Correction=0.37.)

This looks a little better than the original, but not as good as the image corrected in Lightroom. Why? It’s because of how Lightroom passed the image to Photoshop. Rather than passing the original RAW file with all it’s wide-ranging data, Lightroom created a TIFF file, which is inherently low-dynamic range) and passed that to Photoshop instead.

From the Lightroom…Preferences…External Editing menu you can select the format and colorspace of the intermediate images passed to Photoshop, but a 16-bit TIFF using the ProPhoto RGB colorspace is the best option available. You cannot pass a DNG or other RAW-file image with high dynamic range.

What to Do?

Does this really make a difference to you? It all depends on whether you need to recover highlight or shadow details in your images. If not, then go ahead and use the Edit in…Photoshop CS5 feature. But if you want to recover any such data, there are two choices. First, you can do your recovery using the Lightroom Develop module and then Edit in…Photoshop CS5, in which case your corrections will be baked into the intermediate image. Alternatively, you can open the original RAW file in Adobe Camera RAW (ACR) or in Adobe Bridge, which will start ACR for you. This will allow you to make the same corrections as you can in Lightroom’s Develop module since it uses the same RAW file processor engine as ACR.

And if you shoot in JPEG instead of RAW, you don’t have to worry about any of this. Those highlights are burned out and gone for good. There is nothing to recover from a JPEG, which is already an LDR image. You can go from high-dynamic range (HDR) to LDR, but there’s no poing in going the other direction. Once you’re in the LDR world, the extended data is forever lost.

Edit in…(something else)

What about all those other options under the Edit in… menu? If you have some plugins installed, you might see them listed there. Passing an LDR intermediate image to these plugins is the only option. Therefore, if you want to recover highlights or shadows, you must do that in the Lightroom Develop module before invoking the plugin. My suggestion is that you also perform certain other Develop-module tasks before invoking the plugins such as Lens Correction — the plugin may delete the lens’ EXIF data — and preliminary sharpening and noise reduction.

[If you have any comments or questions related to this post, please make them on my Google+ page. There are a lot more photographers reading g+ than reading my blog!]

Update!

I’ve discussed this issue and my idea that Edit in… might support DNG intermediates in LR4 with Eric Chan, one of Adobe’s ACR gurus on the Adobe Labs Forum. Eric made a good case for why this might not be an appropriate feature. You can read the discussion here.

But over on Google+, Marko Haatanen provided a solution. In LR you can Photo…Edit in…Open as SmartObject in Photoshop… It won’t appear as though you’ve successfully moved the RAW file into PhotoShop, but if you double-click on the SmartObject in the Layers panel Photoshop will open the image in ACR. And if you’ve previously made adjustments in Lightroom’s Develop module, you’ll see them there, slider-for-slider. (Remember LR’s Develop module is virtually the same as ACR.) Very cool.

If you select two or more images in LR and go for Photo…Edit in…Open as SmartObject in Photoshop…, you’ll get the same number of images in Photoshop. But if your goals are either HDR or you just want to mask-in selections from multiple selections, what you really want is a single image with a SmartObject layer for each original. Again on Google+, Tarun Bhushan showed me how to do this. “In PS, click on a Smart Object layer in one open document and use Duplicate Layer. In the dialog that comes up, choose the destination document as the one where you want the Smart Object to be as a layer. Now you will have the two Smart Objects as layers in one document that you can then manipulate independently.”

I’ll have more to say about this as I continue to explore some of the best options for HDR in particular.