Converting TIFF to DNG

[_H__G__Smith_]

It's possible to convert a TIFF file to DNG in Lightroom, and I could have sworn I had done it at least once with the DNG Converter that comes with the Camera Raw plug-in. Now it works only with Lightroom. Is there some way to convert a TIFF file to DNG in Photoshop alone? I'm currently using CS, not yet having had time to upgrade to CS3.

[JimHess-8IPblY]

Thank you for setting me straight, Jeff. I have used ACR to edit JPEG images frequently, but had never considered that there was any value to saving them as DNG files. I will have to go back and give that a try on some of them.

[_Jeff_Schewe_]

>BTW, it was my understanding that some future rev of DNG was going to be tweaked
a bit to handle tiffs and jpegs better. Any insight?

You mean a future rev of Camera Raw? I can't comment on thatother than to say that even Camera Raw 4.5 now has it's own virtual memory and can open a 512MP imagewell beyond the old limit of 10,000 pixels.

[Thomas Knoll]

When using just Adobe products, there is not a strong workflow reason to convert JPEG/TIFF files to DNG. The workflow benefits mostly come in mixed company workflows where you take advantage of the embedded previews possible in a DNG file. This would allow to make "non-destructive" changes to the underlying JPEG/TIFF data, and render previews to embed in the DNG so non-Adobe software (e.g. a third party DAM) can see the adjusted preview images.

The big downside of converting JPEG files to DNG is the size increase due to the lack of a lossy compression option in DNG for the main image data. This is not an issue of TIFF files converted to DNG since the lossless compression in DNG is actually quite good, and can sometimes result in the DNG file being smaller than source TIFF file despite the embedded previews.

[bkolmsted]

I experience this. When I scan my images to tif and then edit in lightroom, the embedded xmp data for the current state of the image is reflected when I view the previews with Adobe Bridge or PS. However, the embedded preview according to my Mac OS does not reflect any of this and creates a confusing situation when sifting through files using the OS natively. However, converting to dng does not allow previews to be displayed by the Mac OS and reminds me I have to use Bridge.

[_Sean_Clarke_]

Thanks for that Eric, I had a feeling that might be the case but talked myself out of it. Surely this capability is as relevant to JPEGs as it is to RAWs and not so difficult to implement. One for the wishlist to go to Adobe perhaps?

[_Emmanuel_Giasson_]

Hi everybody, I have this TIFF to DNG issue too.

Actually, I have a negative scanner which gives me 22 Mega-pixels, 48-bits TIFFs. I've scanned a lot of old negatives and I'd like to process those "now-digital" negatives with the same workflow than my "genuine digital" camera raw files (correcting chromatic aberration, vignetting and all the usual whitebalance, exposure, etc. stuff). Please note that I have access to Photoshop CS2, not CS3, and the latest Camera Raw plug-in supported by CS2 is version 3.7, which
doesn't support TIFF files as input. It does support DNG though.

So, does that sound now like a good reason to convert TIFF to DNG?

That should be easily done, but even Adobe Digital Negative converter 4.5 won't use TIFF as input files.

I'd just like to do that (dumb) conversion without buying additional software (or I'll have to code it myself with the DNG specification... don't have that time right now). Any ideas?

[JimHess-8IPblY]

The DNG converter only converts raw files to the DNG format. It never has converted TIF images to DNG. Since you only have Photoshop CS2 I don't see any way for you to make the conversion to DNG.

[KC2PED]

I also want to convert TIFF to DNG.  I scan my 4x5 pinhole negatives to TIFF and load them into Lightroom for processing and storage.  The camera produces considerable stretching in the corners of the image.  I want to create a lens profile (for a lens less camera) to take care of the distortion.  It is my understanding, which is often imperfect and growing more so as time marches on, that profiles will only work against DNGs.  Also, you can validate the checksum of a DNG which will warn you of bit rot so you can refresh the active file from backup.

I thought I read so where that whatever file format you give Lightroom it processes it as a DNG.  If that is the case then 1) you should be able to apply a profile to any file you can open in Lighteoom, and 2) you should be able to export the open file as a DNG.