Lightroom and Snow Leopard

After a comment by Derrick Story on Twitter, Tom Hogarty (Lightroom Product Manager) posted an announcement on installing Lightroom under Snow Leopard. Due to an incompatibility between the original installer for Lightroom 2.0, Lightroom cannot be installed from the disk. While this issue was fixed with Lightroom 2.1, you'll still be better off downloading the current version from Adobe and using that to install. Each version is a full installer, so you would be downloading this file to update from the disk version anyhow. All you'll need then is your serial number and you'll be good to go.

RGB conversion chart

Because Lightroom use a percentage scale rather than the older 0-255 scale, a lot of people ask for such a scale to be added to Lightroom.
While in theory it seems like you just convert the numbers and you're done, it's actually not that simple.
The 0-255 scale is a measure that comes from 8 bit files. There are only 256 levels in each of the channels, so such a number can accurately describe any 8 bit colour. 16 bit colour has 65536 levels per channel. Thats a huge jump in the number of colours and a larger margin of error is we use a 0-255 scale. In truth Raw files are 12 or 14 bit, and a 12 bit file would have 4096 levels of colour per channel. Even that is an unwieldy level to use.

Lightroom founding Engineer Mark Hamburg choose to use a 0.0 to 100.0 percentage scale, which with 0.1 accuracy gives use 1000 levels of colour. Finer than 0-255, but still not in the order of 12 bits per channel colour.
The other issue with a 0-255 scale in Lightroom, is that even if you had one, it is only accurate for the Lightroom working space. To use the words of Jeff Schewe: Admittedly, since Lightroom uses an unusual color space internally (ProPhoto RGB Chromaticities and a linear gamma for processing, but an sRGB gamma tone curve for histogram display), there are no traditional color readouts to be had. Insiders call the Lightroom color space Melissa RGB, named for one of the Lightroom team members. (We like it because as far as we know, it's the first color space named for a woman.) So this would be completely inaccurate if you were exporting to any other space. Still people would ask for such a thing.

One possible compromise would be to have an option to see the values as if it were exported to an 8bit sRGB space. I'm not optimistic that such a thing would be possible, and to be honest, we do need to start thinking in more accurate colours. Anyhow, here's a rough conversion guide for % in RGB numbers. Bear in mind that when you export, these will be subject to the rendering of the conversion engine in Lightroom, and so will be different on export. Try it and see the difference.

Rough conversion between % and RGB255 numbers

Update Jao Van De Lagemaat has posted a link to his blog on the comments with conversion number for the MacBeth colourchecker chart.

Where to keep your Lightroom Plugins.

There's been some questions and concern expressed in a few places about the where you should keep your Lightroom plugins (I'm not referring to Web Engines here, they do have a specific place).

The SDK tells us that Lightroom looks in a specific place for Plugins.

In Mac OS (current user) ~/Library/Application Support/Adobe/Lightroom/Modules
In Mac OS (all users) /Library/Application Support/Adobe/Lightroom/Modules
In Windows XP C:\Documents and Settings\username\Application Data\Adobe\Lightroom\Modules
In Windows Vista C:\Users\username\AppData\Roaming\Adobe\Lightroom\Modules

Plugins located here are automatically loaded and can be both enabled or disabled by the Plugin Manager, but not removed.

This lack of removal is causing pain for a number of users, so a few Lightroom users/gurus/developers were talking about this a while ago. We bantered back and forth about how we work around this limitation. In the end we figured on a simple solution. Manually create a folder beside Modules called 'Plugins' and store your plugins there. This allows you to have a central repository for all your Lightroom plugins, and to be able to add or remove them using the Plugin Manager. This isn't any kind of mandatory or definitive solution, but may be of use if you feel you need to be able to remove plugins without losing them.

Updating Lightroom 2.1 to Camera Raw 5.1

As this is in a comment on the last post, I thought I'd mention this:
Lightroom does not use Camera Raw as a plugin. The two applications share the same codebase and are generally released at the same time.
In the About Lightroom box for 2.1, it states Camera Raw 4.6. This merely indicates that the 2 are compatible for use with Edit in Photoshop.

Where people are getting worried is with the fact that they don't know that Camera Raw 4.6 and 5.1 are actually compatible.
Camera Raw 4.6 is the final Camera Raw release for Photoshop CS3. Camera Raw 5.1 updates Camera Raw 5.0 for Photoshop CS4 to be compatible with 4.6. This means that, for now, users of Lightroom 2.1, Photoshop CS3 and Photoshop CS4 are in sync for Raw processing.
When Lightroom updates to 2.2 and Camera Raw to 2.2 (I suspect this will happen for historical reasons, if nothing else), then Photoshop CS3 users will be left behind. Of course the DNG convertor will be updated and you can still access changes that way.

So don't worry about updating Lightroom 2.1 to Camera Raw 5.1. It already is.

Lightroom 2 vs. CS4 & Lightroom Conspirarcy Theories

Scott Kelby has posted a video about Lightroom 2 vs. CS4 & Lightroom Conspirarcy Theories over at his Photoshop Insider blog. Basically the video is Scott and Matt Kloskowski talking about coverage of issues relating to the programs.
A very valid point is that while the majority of users don't have issues, there are some that do, and for them it's the most important thing in the world (appropriately).
Personally, I'm having a bizarre graphic issue where my screen darkens down as I move the image about the screen or scroll using any scrollbar. I move the whole window to my 2nd monitor and it rectifies immediately.
Here's the catch: to create an effective bug report that lets Lightroom engineers see the issue, you need reproducible steps. While this happens to me all the time, I have no steps. It simply happens.
Besides that I have only one minor crop issue and that's it. Lightroom is solid otherwise. The crop issue, for those that care, is when I'm in a portrait image and I use Shift to constrain a crop, it jumps to landscape when I drag a corner. It happens most of the time for me. If I use the lock it's fine, so it's not major by any means.

Update: Folks, if you're going to say you've a bug in the comments, do it the right way! List your machine and OS, the version of Lightroom you are using and the steps to take to reproduce it. If you've no steps, describe what you were doing when you see the bug.

Keyword Export issue fix

Adobe has published a technote containing a script that fixes the 'Include On Export' issues users are seeing with their keywords. The note details ways of solving the issue with or without the V1.x Catalog available.

Official Adobe Statment on version 1.4

Tom Hogarty, the Lightroom Product Manager has weighed in on the recent issues with the 1.4 upgrade:

"The Lightroom 1.4 update for Mac and Windows has been temporarily removed from the Adobe.com web site.  Those Lightroom users who have installed Lightroom 1.4 should uninstall the update and install Lightroom 1.3.1.(Mac, Win) until a further update can be provided. For those not in immediate need of the updated camera support available in Camera Raw 4.4 or the DNG 4.4 Converter, it's recommended that you also continue working with the 4.3.1 versions. (Mac, Win)"

Read More .

How do I downgrade to an earlier version of Lightroom?

Ian Lyons has posted details on downgrading from Lightroom 1.4 over at the Adobe Forums. Users affected by issues with DNG, timing and Jpeg previews should consider this option. If you're not, 1.4 seems fine bar the issues.

On Windows, DNG previews are not created correctly. When you try to view at 1:1, an error message is displayed. One user has noted that this only happens on landscape images and not on portrait image. While I have confirmed the error, I've not confirmed the orientation report.

Other issues include the time being set to midnight on the export date in the EXIF with image Export. It's not immediately obvious to a lot of users, because both Photoshop and Lightroom will show the correct time. This is because they are reading the internal XMP information rather than the EXIF. Use an EXIF reading tool to see the correct EXIF time.

Lightroom also appears to be writing times into RAW files when saving XMP. Normally the only thing that can change this is deliberate use of the Edit Capture time command. The RAW file shouldn't be changed at any other time. Ian has confirmed this as a bug, rather than intended behaviour.

Certain Olympus users with a recent firmware seem to be having random JPEG preview issues. A smaller version of the file appears embedded in the main image. Thomas Knoll has asked people to post links to such pictures.

It's unfortunate that such bugs have slipped into a bugfix release. I know the team will be straight onto fixing these. The only thing I might have found in my workflow is the time issue, but as I was viewing results in Lightroom, I would've missed it anyhow.