Lightroom faster than ACR for RAW??

Rhuarc

I don't know if anyone else has notived this or not, but it seems like Lightroom is much faster than ACR for RAW processing. Since the two programs process RAW the same way, I've just been using Lightroom as my RAW processor. Anyone have any idea why this is? The only thing I can come up with is that since Lightroom writes the changes to a database at first, not *.xmp files it is faster to the database.

I've just been doing all my processing, then exporting the changes to xmp before converting to DNG, and importing the processed DNG's into IDImager.

Has anyone else experienced the speed difference between Lightroom and ACR?

arodney

The use the identical processing engine so its doubtful.

Rhuarc

They may use the same processing engine (I'm sure you are right) but Lightroom by default writes the changes to an internal database, where as ACR writes the changes directly to the file. When I have 300 CR2's loaded into Lightroom the program chugs along nicely with no hickups. If I tried the same in ACR it would slow to a crawl and probably crash. I'm figuring this is because in ACR all 300 files are "open" where as in Lightroom changes go to a database, so all the files don't need to be accessed the whole time.

Again, I could be wrong, it just struck me as strange.

CatOne

Rhuarc wrote:

They may use the same processing engine (I'm sure you are right) but Lightroom by default writes the changes to an internal database, where as ACR writes the changes directly to the file. When I have 300 CR2's loaded into Lightroom the program chugs along nicely with no hickups. If I tried the same in ACR it would slow to a crawl and probably crash. I'm figuring this is because in ACR all 300 files are "open" where as in Lightroom changes go to a database, so all the files don't need to be accessed the whole time.

Again, I could be wrong, it just struck me as strange.

ACR doesn't write the changes to the files. It writes them to XMP files or it writes them to another metadata location (depending on how you have it set up). Writing to XMP is slower -- you can do this with LightRoom as well and it slows it down.

arodney

Rhuarc wrote:

They may use the same processing engine (I'm sure you are right) but Lightroom by default writes the changes to an internal database, where as ACR writes the changes directly to the file.

Depends on the file and the preferences. And what its writing is a small metadata file.

In ACR, if you click Done (not open) the file is written.

Now there's a heck of a lot of other functionality in LR compared to ACR. So its possible there are processing differences in that respect. And there may be some speed hits with a plug-in versus a stand-alone. I would hope these differences would be negligible.

Rhuarc

arodney wrote:

Depends on the file and the preferences. And what its writing is a small metadata file.

In ACR, if you click Done (not open) the file is written.

Now there's a heck of a lot of other functionality in LR compared to ACR. So its possible there are processing differences in that respect. And there may be some speed hits with a plug-in versus a stand-alone. I would hope these differences would be negligible.

Unfortunatley these differences aren't negligable, at least not when dealing with large numbers of files. I can easily have 500 shots open in LR, and it will barely slow at all through several hoursof processing all of the shots. If I tried to use ACR to process the number of files till I got to the 30th or 40th shot it would almost be unuseable. Also, the sliders aren't nearly as responsive in ACR as in LR when a large number of files are open. I don't think it is my system.

I'm running Ahtlon 64 X2 3800+, 2GB Ram, and dual video cards (not that I think this matters). I suppose it is just the difference between writing directly to xmp files vs writing to a database. The database writing is just plain faster. I guess I'll just have to continue to use LR for processing large shoots.

Thanks for the input!