Hi Gary. Thanks for taking the time to reply. The image in question is 32MB. I can send a copy to your email if you like. Alternatively, perhaps I can make it available via http for you to grab. Are there any tools I can use to determine which tag we're looking at myself? I tried tiffinfo but can't find much information on numeric tag indexes. 

On 9 Jul 2013, at 14:32, Gary McGath wrote:

JHOVE recognizes TIFF tag 41488, Focal Plane Resolution Unit (Exif
Private), which can have the values 1 (no unit), 2 (inch), and 3
(centimeter). Tag 37392 is also called Focal Plane Resolution Unit.
JHOVE defines both of these with the constant FOCALPLANERESOLUTIONUNIT
in two different classes (ExifIFD and TiffIFD respectively), so they
don't cause a compile-time collision. There's also an array of String
values for each of these, which are different.

There might be some place where the code is mistaking one for the other,
though I can't spot it at a quick glance. If the tag is 41488 and the
value is 4, that looks like an error in the file. Are you sure the tag
in question is 37392 and not 41488? If you can send me a file that
causes a problem, or submit a bug report on SourceForge, I could see
what JHOVE is actually doing.

On 7/9/13 7:52 AM, Dan Field wrote:
Hi, I'm trying to validate a TIFF from a Nikon D800E camera which, via the Adobe RAW plugin is generating a FocalPlaneResolutionUnit value of 4. This is being thrown back by TIFF-HUL as invalid yet from what I can see in the ISO standard doc cited in the documentation, values of 4 and 5 should be valid:

macdanosx:~ dof$ ./bin/jhove-1.10/jhove -c ./bin/jhove-1.10/conf/jhove.conf Desktop/arm04454.tif
Jhove (Rel. 1.9, 2013-06-10)
Date: 2013-07-09 12:36:27 BST
RepresentationInformation: Desktop/arm04454.tif
 ReportingModule: TIFF-hul, Rel. 1.7 (2012-08-12)
 LastModified: 2013-07-09 12:28:57 BST
 Size: 32375880
 Format: TIFF
 Version: 6.0
 Status: Well-Formed, but not valid
 ErrorMessage: FocalPlaneResolutionUnit value out of range: 4
 MIMEtype: image/tiff

And the relevant part of ISO 12234-2:2001(E)

2.11 FocalPlaneResolutionUnit

This tag encodes the unit of measurement for the FocalPlaneXResolution and FocalPlaneYResolution.

Tag Name = FocalPlaneResolutionUnit
Tag = 37392 (9210.H)
Type = SHORT
N = 1
Value = VALUE (possible values listed below)
1 Inch
2 Metre
3 Centimetre
4 Millimetre
5 Micrometre

Can anybody shed any light on this issue?

Gary McGath            garym@mcgath.com

Dan Field <dof@llgc.org.uk>                   Ffn/Tel. +44 1970 632 582
Pennaeth Uned Datblygu                        Head of Development Unit
Llyfrgell Genedlaethol Cymru                  National Library of Wales