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I set my camera to take raw images, I have a Nikon so all the images are of .NEF file format. I can convert it to JPEG and PNG with my Mac but now I need the NEF format again to do some editing. But when I convert it back to NEF (with ImageMagick) Photoshop tells me that it is a filetype that it cannot read, even if the NEF extension is there.
Is there any tool I can use to get back my NEF file?
3
Answers
You cannot get the real .NEF back from a JPEG or PNG. Just like you can get back a steak from a burger, or get back the cattle from the beefsteak.
.NEF stores much more information than JPEG or PNG (and JPEG is a lossy image format, which does not allow you to recover losses — once they were lost, they’re lost forever).
You can as well do the editing in whatever format you have now.
Remember to never throw away your original .NEF, but keep it as a backup in case you want to do high quality editing in the future.
Having said that, you should still be aware of the following points:
There is still some value in converting camera raw files to JPEG, PNG or TIFF: because .NEF files are not so much for direct consumption (just like living cattle aren’t, as opposed to steak or burgers). If you send a .NEF to your grand dad, it’s not just about the pure file size to be transfered: he’ll likely not be able to view it (unless he has expensive or special software installed), while a JPEG or a PNG he surely will be able to open in any browser. That’s why you convert .NEF to these easier accessible formats in the first place.
Of course, you can convert a JPEG or PNG image to .NEF format, technically. But this will not give back any of the real info which was contained in the original .NEF. You may also re-gain the same image dimensions that were there originally by up-scaling it, and the .NEF can have roughly the same file size. But what you get as additional pixel data is not the original data, it is (at best) just interpolated data from the (lossy) pixels that had been in the JPEG or PNG. (All the detailed metadata inserted by the camera into the .NEF about the exact conditions of the shot may have been lost forever.
So if saving disk space is not an urgent current requirement, it is always a good idea to:
According to this forum, the answer is no.
A NEF file is going to be large and hold the most data. JPEG and PNG are going to lose some of that data.
In short, as Kurt rightly says, you cannot get your cow back if you have the burger 🙂
And further, as Kurt also says, you can just edit the JPEG you still have in Photoshop.
If, however, your question means there is something you want to do in Adobe Camera Raw (ACR), or some feature in there you want to use, you may still have a chance. ACR can also read TIF files, and you can convert your JPEG to a TIF with ImageMagick, like this
You won’t suddenly get back 12/14 bit data or extra highlight detail or lens data that was in your NEF file, but you may be able to use some features in ACR.