My 30 day free trial for DxO NIK Collection with PhotoLab 2 is almost over and I have a question about how Canon raw files are handled so I can make a decision on if I am going to buy this or stick with Photoshop… First, does DxO PhotoLab 2 edit using all the data in the raw file? The jpeg is a compressed file and has less data but the CR2 file has all the data captured in the image. Is there still an advantage to edit the raw file over the jpeg? Second, in Export to Disk, why can I not save the CR2 file? I either have to convert it to a DNG file or a TIFF both of which are extremely huge, at least 5+ times larger than the size of my CR2 file. If I use the external DNG Converter software to convert my CR2 to a DNG file, it is basically the same size. It does not become huge like your saved version of a DNG file. This may be the show stopper for my workflow. I’ll some home from travel with 2000 images and rate them only saving the ones rated 3-5 stars. I want to rate them in PhotoLab and save them as the CR2 files but can’t. Thanks.
There will always be an advantage to shoot and edit raw over using jpeg only.
JPEGs are meant for getting decent quality with the smallest file size possible. They use only 256 shades of each (R, G and B) colour and areas that look similar are simplified. Editing and saving jpeg files over and over lead to reduced quality.
RAW files store image data with between 2’000 and 16’000 shades per colour which prevents all kind of undesirable effects you get with jpegs. In order to preserve the quality, raw files are not altered by most apps. Instead, changes are written into a database and in sidecar (DPL creates .dop) files. These are the recipes that describe how the app processes raw data in order to get your image look like you want it.
Keeping the raw files unaltered also means that you’ll have to store your files separately. DPL offers TIFF, DNG as well as JPEG to that end.
RAW files are the digital equivalent of a film negative or slide - they can never be edited.
What RAW development software like DxO does is to create a record of the changes you apply to the image (in the case of DxO, in a .dop sidecar file). There is no such thing as a single, edited image, file - for that you need to export to a bitmap format, at which time DxO will merge the original image with the changes to create a file that can be either jpg, tiff or dng.
Unless you have immediate need to share the file, you don’t need to save or export it as it can be created at any time from the original file plus its sidecar.
You also don’t need to record RAW + jpeg in your camera, unless you need the jpeg for immediate sending to someone, the RAW file actually contains a full-sized jpeg preview version as well as the RAW data. This means you don’t fill up your memory card so quickly and, subsequently, your disk.
Your workflow should be:
- RAW only in the camera
- transferred to your disk and organised in folders
- worked on in DxO, which will create .dop sidecar files
- left as they are until you need to create a definitive copy to transfer elsewhere (usually as a jpeg for web/mail or tiff for printing)
Whether you edit the raw file in DXO-PL2 or PS the only way you can get an image out is to save as a RGB file eg tif or a jpg. The image you view on screen in PS or DXO is a debayered image.
When you convert a CR2 file in Adobe DNG converter you are simply re-writing the bayer data in a slightly different way i.e from Canon raw format to DNG raw format. Both are still raw files and you can’t do anything with them until you use a raw converter to produce a jpg or tif.
When you save a DNG file from DXO-PL2 you are demosaicing the raw file into a linear DNG, (DNG is simply a container format, just because it says DNG does not mean that it is a raw file). A linear DNG is basically a tif file.
You cannot save a CR2 file because this is a raw format i.e. the data is in a bayer format. Only the camera can create a raw file.
I hope this helps. The fact that DNG is simply a container for different types of files can be confusing and people often think that they are using a raw file.
Always edit the raw to produce a jpg. The camera jpg is produced from the raw file in camera using an automated process. If you do the raw conversion you get the chance to improve the result. Even something simple like white balance. You probably don’t do a custom white balance in camera before every shot and the camera makes its best guess. With raw you get the chance to make that choice at your leisure 
Ian
Thank you , Joanna and Platypus for responding to my question . Much appreciated. Joanna, the step you mentioned “transferred to your disk and organised into folders” is the one that I will have to change. It sounds like you are suggesting that I transfer ALL my images to disk but I prefer to review and rate them first and only transfer the ones I choose to keep and save the raw files. I think I will still need to do that step in Photoshop Bridge. But no big deal really, was just hoping to get away using Photoshop entirely. I will probably be going forward with my purchase of DxO software. I love the editing functions!