I can open files fine in Photoshop CC, but if I try to use the Camera Raw filter, I get the "file format module cannot parse your files" error. This only happens with larger TIFFs, say 300 MB or so - 70 MB files work fine.
300MB Tiff seems like a large files size for a Tiff which leads me to believe its a layered Tiff. ACR does not have Layers support try opening the Tiff file in Photoshop not through ACR to see it there are layers. If there are target all of them and convert to a smart Object then try ACR as a filter. A smart object is a single layer in Photoshop.
Thanks for your reply. The files are single-layer scans from medium-format film. No layers or adjustments, just tiffs straight from the scanner (except they have been downsized and inverted in PS before I attempt the Camera Raw filter).
Can you open it into Photoshop as a Tiff not through ACR? Can you display it using a image viewer?
As I described in my original post, I can open the files OK in Photoshop, it's only when I try to apply the Camera Raw filter that I get the error message. (It may occur in other circumstances as well, but I haven't come across any yet.)
Edit: I can see the confusion: I'm not talking about ACR per se, but the *new* Camera Raw filter.
I know this is a couple of months old but just had the same problem with large file 5x4 provia tranny scans. The only way I found around was to import them into lightroom then export them as DNG's.
Opened them up as smart objects in PS and can maintain adjustments via ACR. The file size dropped about 100mb, but file is still 62.87cm x 79.12cm. You lose some quality but at least you can edit them.
Hope this helps.
Better late than never.