I have started to do some testing of LR3 and found some interesting differences. I started with the same RAW image and processed it identically in LR 2.5 and the LR 3 beta. I exported the image as a JPG using identical settings. First, I looked at the File Info in CS4 - the Raw Date tab, and found the following differences

1. The LR3 image exported as a 9.91 MB file. The LR2 image was 7.14 MB

2. The LR3 image contains some EXIF data not in the LR2 image
<exif:SubjectDistance>113/10</exif:SubjectDistance>
<aux:LensID>224</aux:LensID>
<crs:RenderVersion>5.7</crs:RenderVersion>
<crs:GrainAmount>0</crs:GrainAmount>
<crs:ColorNoiseReductionDetail>50</crs:ColorNoiseReductionDetail>
<crs:NoiseReductionContrast>0</crs:NoiseReductionContrast>

3. The LR2 image contains some EXIF data not in the LR3 image
<crs:LuminanceSmoothing>0</crs:LuminanceSmoothing>

The biggest difference is in the appearance of the two images. I will leave it to you to decide what you think about the two. The first image is the LR2 image. The second is the LR3 image. It appears to me that LR3 added some grain even though the grain was set to 0.

In PS, I did nothing but identical 100% crops, resize to 1000x714 and save with the compression set to 8.

I think you can see some of this same effect in another LR2/LR3 comparison thread....
http://www.fredmiranda.com/forum/topic/826895/2#7681866

Could it be the lack of luminance NR in 3 beta?

Make sure you have enabled the new process version by clicking the exclamation mark above the histogram in the develop module.

You may also have to change your sharpening settings as that has changed quite a bit since v2.

All settings were adjusted to the same levels in both versions. I am quite certain that the differences you see are differences in between the versions, and not differences in the settings. Started off by pressing reset to return the images to as shot.

NR: 0 ,50
Sharpening: 110, 1.0, 25, 0
Grain: 0 in LR3
Export Sharpening: Off

LR3 didn't add grain—it just didn't make the image into a smeary mess. What you're seeing is color noise processed by a competent tool.

It's also the reason a lot of people have traditionally preferred DPP or Capture One over ACR/Lightroom. Adobe's raw engine has long had an awful noise reduction algorithm. LR3 is the first time we're getting to play with both their new demosaicing algorithm (already increasing quality) and their new noise reduction (further increasing quality).

colinm wrote:
Adobe's raw engine has long had an awful noise reduction algorithm.

I don't see that... I actually prefer LR NR over DPP NR.

How about the difference in CA between the two sample images? The LR2 conversion shows a lot more CA on the guys shoulder.

The new demosaic will actually look noisier than the old one because it's not apply any NR as part of the demosaic - but the result is an image that will respond far better when NR is applied in the Develop module. Once the luminance NR is active again, the LR3 image looks a lot better.

I've found the sharpening in LR3 to be significantly better. It does appear to have a very fine "noise" at 100% but nothing that would show on a full size print. It also appears to have much less "smeary noise" as someone else suggested. Many thanks for the improvements there.

The highlight recovery is still a bit sketchy. I found a number of other software programs to handle blown or nearly blown highlight details much better than LR. Then again, I suspect we haven't seen all of the improvements just yet.

I'm finding comparable differences which your shots illustate well. I tweak mine as much as I know how so far and get better results but similarly different.
The MKii files are horid imho compared to my D700 files no matter what I do. I wonder if it is the LR and 5Dmkii files combo ... or is it just that the 5Dmkii is not so hot in low light?

I'd rather have the second version personally - by a wide margin. Noise ninja to the rescue later.

Thanks for posting your findings and being a LR 3 guinnea pig. I am an avid LR 2.5 user and am looking forward to improvements in noise reduction and sharpening in version 3.

Scott

Maybe someone has mentioned it before or on another thread but why is the luminance slider locked on some installs including mine

george malamis wrote:
Maybe someone has mentioned it before or on another thread but why is the luminance slider locked on some installs including mine

The noise luminance slider is locked out on all installs ... it's not ready yet but will be added in the final release .... if you import images with LR adjustments saved to XML data from earlier versions of LR, the luminance slider is available .... but will only adjust based upon the tool settings from the earlier version of LR.

has anyone done tests of LR2, LR3 and ACR 5.5? or would ACR be the same thing as LR?

Despite your results here, I very quickly noticed a subtle but distinctive improvement in the LR3 renderings. Depth effects and sharpness are much better. I use LR almost exclusively, but when I compare to DPP, that "smeary" look mentioned above is obvious - and it wasn't in LR3. My first thought was "wow, this is going to make a lot of photographers better " I can't wait for it to come out. Super zippy on Windows 7, too.