any downside to DNG?

[John Chardine]

Following along from this thread:

http://www.birdphotographers.net/for...ad.php?t=54408

I will likely use Adobe's DNG converter to convert mark IV files (once I get the camera!) rather than playing the Photoshop upgrade game with Adobe. I'm happy with CS3 but it will not read the RAW files from the new cameras.

So I would convert the CR2 (Canon RAW) files to DNG and then open them in ACR 4.6. Just tried it and it works.

My question is: as far as processing the DNG file versus the CR2 file, is anyone aware of any drawbacks to starting workflow with a DNG? Are you losing anything by way of digital information that may have been in the original proprietary RAW file? Put another way, is converting a CR2 file to DNG then bringing the DNG into ACR the same as bringing in the CR2 file to ACR directly?

[Axel Hildebrandt]

I don't know if you lose anything by converting to DNG rather than working on the CR2 file, but since you are in higher education, CS4 costs less than $200. I read some reports that Adobe will release the next PS version sometime this spring.

[Dug Threewitt]

I don't know if this will be the case with the MK IV, but with previous .cr2 files the adobe versions were quite a bit noisier than alternatives(DPP, Bibble, BBPro). That looks to be changing with the next version of camera raw, but that will likely require cs5(or lightroom 3). As "open" as the dng standard is, I don't know of any apps besides adobe's that support it.(that could be because I don't use it though)

[Roger Clark]

My understanding is that the DNG format is simply that: a format change and header change with no change in the data. But the difference you may see is the availability of algorithms that construct the RGB image from the raw data. The canon raw files are pretty simple. I have written my own code to extract the data from the raw files, so it would be easy to change the format without changing the actual data values.

Roger

[Alfred Forns]

Hi John The only downside I can think is that you don't have the RAW file anymore and if you enter a contest which requires RAW ... the DNG will not be accepted !!! A big advantage of the DNG is having all the info in one file, no sidecar !!!

[John Chardine]

Hi John The only downside I can think is that you don't have the RAW file anymore and if you enter a contest which requires RAW ... the DNG will not be accepted !!! A big advantage of the DNG is having all the info in one file, no sidecar !!!

Thanks for all the useful replies.

Al- I noticed when trying out Adobe's DNG converter that it offers an option to embed the original RAW file within the DNG file. I'll try this and see if it solves the problem you raise. Also interested to see how big the resulting file is!

[Axel Hildebrandt]

Thanks for all the useful replies.

Al- I noticed when trying out Adobe's DNG converter that it offers an option to embed the original RAW file within the DNG file. I'll try this and see if it solves the problem you raise. Also interested to see how big the resulting file is!

1D Mark IV 16bit TIFF files at 300 dpi are 96MB.

[Cliff Beittel]

Yes, embedding the RAW file in a DNG doubles its size.

On Dug's point about other applications not using DNG: wrong. The only reason I use DNG (with RAW files embedded) is that catalog software like iView MediaPro and Expressions Media can read a DNG file and show the image as optimized in ACR; feed either of those programs an ACR-optimized Canon RAW file and they can only show the image as it came from the camera--a very unsatisfactory result.

[Roger Clark]

Hi John The only downside I can think is that you don't have the RAW file anymore and if you enter a contest which requires RAW ... the DNG will not be accepted !!! A big advantage of the DNG is having all the info in one file, no sidecar !!!

Alfred,
There is no reason why you couldn't save the original raw file.

Roger

[Dug Threewitt]

...

On Dug's point about other applications not using DNG: wrong. ...

Thanks for the correction. Since I don't use it, I never see it anywhere.

[Alfred Forns]

Hi Roger, yes the original can be saved but I was thinking of the extra room. Having the original at two sets of back ups takes up a lot of room !!!

[William Malacarne]

Can you just work with the DNG and archive the RAW?


Bill

[Jeff Donald]

Hi John The only downside I can think is that you don't have the RAW file anymore and if you enter a contest which requires RAW ... the DNG will not be accepted !!! A big advantage of the DNG is having all the info in one file, no sidecar !!!

Are you sure DNG's would not be accepted? DNG is just Adobe's Raw format, like Canon has CRW and CR2, Nikon has NEF, and Adobe has DNG. The Leica M8 uses the DNG Raw format, so Leica M8 owners can't enter some contests? I believe some medium format cameras use DNG as well.

[Tell Dickinson]

Are you sure DNG's would not be accepted?

I would think that competitions just want the ORIGINAL file whatever format that is, and not one that has been derived from the original.

Tell

[Byron Prinzmetal]

Question: does the dng file contain all of the changes you made in lightroom or does the LR catalogue contain those changes? If lr appendes the changes you made to the dng file and keeps the original file intact then if you lose the LR catalogue you still have your changes.