Generic RAW v DNG

[Patrick]

A friend has just bought a Canon G12, and uses CS4.
Adobe in their usual helpful way don't and wont offer support for such a new Camera for CS4, but naturally do for CS5 but he's not about to buy CS5 just for this camera.
He came to me for help (now that's desperate) so I suggested DNG RAW which we downloaded from the Adobe site and I showed him how to use it.
I then started to think, would it not be a good idea to automatically use DNG, I know many do.
So I downloaded my latest images, a Studio session from Smethwick club converting them as they downloaded, and was surprised to find the files are up to a Mb smaller than my Canon CR2 RAW files does this happen with all generic RAW files from Nikon, Sony and the like or is it just with Canon?

I would also like to know why, if its not too technical.

Patrick

[Graham_of_Rainham]

Re: Generic RAW v DNG

Hi Patrick,

Do you have the "Preferences" set to embed the original RAW file and what size JPEG Preview have you selected.

I only have "medium" preview and Don't embed the original and they convert to DNGs only slightly larger than the ORFs

Also the compatability setting will make a small difference.

Not a full technical answer, but hopefully it may help

[Patrick]

Re: Generic RAW v DNG

Hi Patrick,

Do you have the "Preferences" set to embed the original RAW file and what size JPEG Preview have you selected.

I only have "medium" preview and Don't embed the original and they convert to DNGs only slightly larger than the ORFs

Also the compatability setting will make a small difference.

Not a full technical answer, but hopefully it may help

I haven't saved the original RAW file emended in the DNG file just the DNG I can't actually see the point, its only a RAW image I want for processing.

Patrick

[rogleale]

Re: Generic RAW v DNG

Hi Patrick,
The DNG files can be between 15-50% smaller than the original NEF or CR raw files because of a more effective, but lossless, compression. The advantages of DNG further on in the PP is that all the changes made are recorded in the DNG file and there is no need for the xmp files to be moved around with the original.

Roger

[Ian]

Re: Generic RAW v DNG

Hi Patrick,
The DNG files can be between 15-50% smaller than the original NEF or CR raw files because of a more effective, but lossless, compression. The advantages of DNG further on in the PP is that all the changes made are recorded in the DNG file and there is no need for the xmp files to be moved around with the original.

Roger

Camera manufacturers do embed a lot of proprietary information in RAW files and it's not clear that DNG can maintain this data in a usable form. One example is the focus point used. Others include special effects modes used at the time of shooting. These effects may not apply to the RAW file directly, but may assist a program to reproduce the effect using the RAW file image data as a starting point.

Ian

[rogleale]

Re: Generic RAW v DNG

Do you think that something will be lost in converting, say a NEF, to DNG Ian?
It is unlikely because the DNG file structure is designed to conform to the TIFF/EP standard (EP = Electronic Photography), which dictates not only which data will be included, but how it is arranged in the file. This includes sensor data and metadata.
As the DNG file normally includes a jpeg image the camera settings must be taken into account, so the information must be there for that to be possible.

Roger

[Ian]

Re: Generic RAW v DNG

Do you think that something will be lost in converting, say a NEF, to DNG Ian?
It is unlikely because the DNG file structure is designed to conform to the TIFF/EP standard (EP = Electronic Photography), which dictates not only which data will be included, but how it is arranged in the file. This includes sensor data and metadata.
As the DNG file normally includes a jpeg image the camera settings must be taken into account, so the information must be there for that to be possible.

Roger

My point is that I would be wary of converting to DNG and then deleting my original RAW files. I use Olympus gear and there are lots of features recorded in the RAW files that are proprietary and only recognised by Olympus' own software. I would think that this was much the same, to varying degrees, with other camera manufacturers.

I'm pretty confident that there would be no loss in image quality potential, however. It's just the extras that are now part and parcel of RAW files.

Ian

[rogleale]

Re: Generic RAW v DNG

I must admit that I don't know much about Oly gear Ian, but I am very surprised to hear, by implication, that you won't get the best out of your raw files if you don't use Oly software.
What do you lose?

Roger

[Ian]

Re: Generic RAW v DNG

I must admit that I don't know much about Oly gear Ian, but I am very surprised to hear, by implication, that you won't get the best out of your raw files if you don't use Oly software.
What do you lose?

Roger

Did I say that? I did say that image quality potential is is unlikely to be compromised. But from what I understand, not all the camera make and model-specific data that can be recorded in a RAW file will be recorded (or probably more realistically) be usable via DNG, with the example of focus points used, one example.

I routinely use Lightroom and Photoshop. The Olympus Software I also use is Viewer 2, which can reproduce, from RAW files, some of the Art Filter effects that can be created in the camera (pin hole, grainy black and white, pop art, etc.).

Ian

[Patrick]

Re: Generic RAW v DNG

Did I say that? I did say that image quality potential is is unlikely to be compromised. But from what I understand, not all the camera make and model-specific data that can be recorded in a RAW file will be recorded (or probably more realistically) be usable via DNG, with the example of focus points used, one example.

I routinely use Lightroom and Photoshop. The Olympus Software I also use is Viewer 2, which can reproduce, from RAW files, some of the Art Filter effects that can be created in the camera (pin hole, grainy black and white, pop art, etc.).

Ian

If its only art filters does it matter? all that can be done in Photoshop anyway and under more control. I just checked the Exif date and all the info carried by the Canon CR file is on the DNG file.
What it didn't do was show the adjustments made in ACR on the CR2 files this is lost in conversion, So you simply do your ACR on the DNG files instead
My plan is to use DNG only in the future.

Patrick