IV, (potential) New user, Questions

[Ferguson]

I use Lightroom and am happy with the image load from it, but was looking for a verifier program and managed to stumble into this product and later this site (thanks to a tip on Lightroom Forums).

It appears that one has to buy the ingester to use the verifier.  Unfortunate but not a big issue (or did I misunderstand).

My first use of the verifier I had about 10 NEF's and 3 of them had been edited, so had corresponding TIFF's produced by Lightroom (I did not save the edits from CS3, just used it to cut/paste some crops).

The NEF's all verified (after I downloaded the DNG converter), but the TIFFs all say they may be invalid.  They display fine in both Photoshop, Lightroom, and IrFanview.

I initially dismissed IV as broken, but someone on LRF suggested I look more closely, and this "feature" does seem to be documented.  Also unfortunate, especially that it would appear to fail on a pretty common product's TIFF's.  Not sure what that means.

Does anyone have insight?

Fundamentally what I want is something to run parallel to Lightroom, and periodically check that no bad things have happened, tell me which images have been changed, allow me to relatively easily dismiss those changes when on purpose (e.g. I do a bunch of metadata updates or keywording of old shots).

I THINK it will work in that mode.

Are there any issues using it without the Image Ingester portion?   (Not asking a licensing question but whether one presumes the other was involved)

Are there any more lightroom-integrated choices? (For example taht might reconcile changes known to Lightroom's catalog against changes in hash and only show those that weren't know).

And should I worry that it doesn't do TIFF's well?  I understand the issue that "anything can be inside a TIFF" but is Adobe really producing non-conforming TIFF's?

Linwood Ferguson

PS. Windows Vista, Lightroom 2.3, Nikon

[peterkrogh]

Linwood,
At the moment, data validation is not a terribly easy task.

IV works in two ways.  It can check the validity of the structure of files, using other tools that Marc can include in the program.  And it can make a hash and tell if files have changed since the hash was first created.

• The TIFF spec has not been updated since 1992, so lots of what is happening in many TIFFs is "non-standard" and won't pass a generic validity check.

• The DNG format has a built-in validation code, so it can be checked with much more certainty. 

• A NEF can be checked to see if it's valid, but it still might have corrupted image data, even though the file structure is in tact.

IV Hash storing/checking
• The hash checking can tell if the file has changed since the has was made, which can be great for backup files or any other file that might be put away and not updated (this would work, for instance, for NEFs edited with Lightroom).

• Any change to the files - even the simple change of a star rating or addition of a keyword  - will produce a hash mismatch for files where the change happens to the actual files.

Does that clear up how it works? Ideally, all this stuff would be bult into Lightroom, but at the moment, Lightroom does not even check the hash inside the DNG (although ACR and the DNG converter do).

Peter

[Ferguson]

Thanks Peter.  I think I understand. 

I did find out at least one cause of the invalid TIFF indication -- if I export from LR without compression into TIFF they validate, if I export with compression they do not.  And the hand-off file from Lightroom 2.3 to CS3 is apparently a compressed TIFF.  I'm not sure if that is the default or not, I see that I can change it in the preferences.

But at least this compression from Lightroom will not validate.  FWIW.

I wish there was a standalone version.  $40 is not a lot of money, granted, I just hate buying something I won't use to get the free tool.   

[Marc Rochkind]

Peter has said it well.

So-called structure validation won't work well with TIFFs because of the variability. But, if you know they are OK, you can still compute and save a hash, and then hash validation will work fine.

IV and II are totally independent, although there is a single license code for the pair.

--Marc

[Ferguson]

I bought it and have spent some time with it now. 

I found a corrupt NEF.  It wasn't corrupt at download (because Lightroom imported and created a preview), it hasn't been modified since according to the modify date, but it is bad (really bad, Lightroom can't read it). On a raid-1 disk.  So a tool like this is useful.

It is reporting quite a few PSD files as invalid. 

Probably invalid: T:\Photos\2007\20071215\20071215_1473.psd
   (Wrong expanded width (columns = 3144; expanded = 6288))

If I open them in CS3 and re-save, the problem goes away.  Not sure what to make of that, it was produced by CS3.  Maybe a prior update.  Interesting.

The one thing I can't figure out how to do (and maybe because you cannot) is how to detect a lost file, not a corrupt file.

Is there a way to compare the saved hashes against a new run, effectively an existence check -- did you see all the files?

E.g. if Windows had a directory hiccup and a file either disappeared from disk, or from the directory structure because a pointer got lost, could it notice?  Lightroom does not, at least as best I can tell, unless you either synchronize or touch the image manually or export it, all a bit painful.

[Marc Rochkind]

Sorry, IV doesn't detect lost files. Probably it should, but it doesn't.

--Marc

[peterkrogh]

Linwood,
That corrupt NEF is the kind of indicator that makes me nervous. Something made this happen.  Leading suspects -

• Adjusted across a network and resaved.
• Dropped network connection in transfer or finder crash in transfer
• Bad drive, drive case, or RAM.

It will be interesting to see how many such files are uncovered once people learn how to validate their data. At the moment, it's a total unknown.

As to validation for completeness, the catalog is your best friend there. You can ask it to confirm the presence of all files. This is easier n Expression Media than Lightroom, where it must be done folder-by-folder rather than catalog-wide.  I find that this is really useful to do periodically.  I'm pretty organized about how I handle my files, but even I end up with stuff that was moved or deleted outside of the DAM.

Peter