What information wil be lost during DNG conversion?

[Roelof]

Since a few years now i committed myself to the workflow described in the DAM book. So i'm also creating DNG's.
At the first i assumed there was no data loss during DNG conversion but later i found out that's not complete true;
For example the autofocus points, at least i can not find the info (with EM2 and Bridge).
Yesterday i found out that also the (Exif) lens type is not coming thrue from NEF to DNG... (created with DNG converter 6.4.0.139)
Now i wonder if there is more info in my NEF's that are lost in conversion to DNG?

Roelof

[Bill Lewis]

Hi Roelof,

My DNG's, converted from CR2 files, are showing autofocus points using Breeze Browser 1.9.6.1 and the lens that was used is showing up in the PHOTO EXIF data in Breeze Browser, LR3, EM2 and in Bridge. I have no idea why you are not at least seeing the EXIF lens data. Maybe a NEF - DNG conversion quirk?

Bill

[ScottBuckel]

I use Nikon and I just randomly checked and the lens information does make it into the dngs that I have created.  I no longer use EM2, but the lens information was in the file using Bridge.  I do not normally save the autofocus points so I can not address that aspect of the conversion.

Scott

[Roelof]

Further investigation (with ExiftoolGui) learned that the lens information indeed does make it into the DNG and so it's not a DNG problem but a Expression Media problem.
Strange however is that all images untill 31 dec 2009 do show the lens information and all recent images don't (in Expression Media). You can see in this movie how lens information disappears after rebuilding:
http://dl.dropbox.com/u/25580003/Lens%20Info%20disappears%20in%20EM2.wmv

So in short: lens information is present in DNG but Expression Media does not show them (anymore).

Because it looks like a EM2 problem, i will post further in that section.
Roelof

[Roelof]

My DNG's, converted from CR2 files, are showing autofocus points

Focus point are not that important for me but i'm curious how you can see them in bridge or any other program (DNG's).
The only way i could do it was to open the original NEF's in ViewNX.
Once when they were converted to DNG i never saw them again.
Roelof

[Bill Lewis]

Roelof,

I use BreezeBrowser Pro version 1.9.6.1 which can read focus points from my DNG files. There was a recent upgrade that made this possible and a feature I had been waiting for to streamline my workflow. Breezebrowser is a Windows only app.

Bill