Hermanland

Which is right and which is wrong? I cannot find the exact answer from Adobe XML specification document.

In ExifTool documentation about XMP aux namespace, aux:Lens is defined as tag rather than attribute. However, IDimager generates aux:Lens as attribute rather than tag in the embedded XMP block in jpg image file, causing Zenphoto unable to extract the value of aux:Lens. After I perform a dummy update to the same image file, Zenphoto is able to extract the value of aux:Lens because I found aux:Lens now appears as tag in the embedded XMP block.  Funny enough, ExifTool is able to parse the XMP with aux:Lens as attribute and writes back the XMP block with aux:Lens as tag.

aux:Lens generated by IDimager as attribute

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<rdf:Description xmlns:aux="http://ns.adobe.com/exif/1.0/aux/"
                 rdf:about=""
                 aux:Lens="Pentax smc PENTAX-M 40mm F2.8 sn 5145745 (PK)"
/>

aux:Lens generates by ExifTool as tag

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<rdf:Description xmlns:aux="http://ns.adobe.com/exif/1.0/aux/" rdf:about="">
 <aux:Lens>
   Pentax smc PENTAX-M 40mm F2.8 sn 5145745 (PK)
 </aux:Lens>
</rdf:Description>

As a follow up of my finding, I just found Adobe Lightroom version 3.0 generates aux:Lens as tag rather than attribute, meaning Lightroom version 3.0 behaves the same way as ExifTool. My test steps were similar as above but using raw file with XMP sidecar file rather than jpg file with embedded XMP block so that I dont need to extract the XMP from the jpg file but I believe the principle should be the same.  I just updated the XMP sidecar file (that was generated from IDimager) with Lightroom.  Then, I found that the aux:Lens was redefined as tag rather than attribute.

Considering my DAM workflow, I can see the folder holding the media files can be under following state:

Open, Full, Computed, Reviewing, Prepared, Archived, Re-working, Trash

More explanation will be posted later.

Although some backup tools claim data verification is performed to ensure data is copied correctly, most tools do not disclose how the data verification is performed. How do the tools ensure the file content copied to the backup media is exactly the same as the original one? Some tools state they use binary comparison or checksum or temporary folder but I cannot think of any way to verify the claim that data verification is really performed. Does anyone know a way to do so? To release my concern, I compute checksum to the source folder before performing a backup and then run the same checksum againist the destination folder after the backup.

During the past 2 months, I have been using Olympus C-5050 daily and also in several social events during the weekend. I were amazed to find there are some useful features in C-5050 which I dont even find in all the cameras I have used so far. Firstly, not only I can set the exposure compensation or flash mode with a single press of button, I can also change the iso sensitivity, meter mode, focus mode and even the flash output in the same quick simple way. The use of the jog dial to select the value adds another security measure to avoid changing any setting by mistake. All these can be done without even turning on the LCD and the control panel on top of the body gives clear indication. I did not realize how useful they were until I tried to practice many of the new techniques I read in the flash photography book recently. Furthermore, the option to configure the camera to startup at the last used focal length of the zoom lens is another useful feature not found in my other cameras. I also appreciate the fast lens at both wide end and tele end (F1.8 – F2.6) so that I dont need to worry the lens getting slow when I zoom in. The lens at tele end is even faster than most lens at wide end.  Foto quality wise…well, there are already many reviews and user comments about it.  It is a typical Olympus color and rendition whether you like it or not.  I like it of course:-)

Some portable DC today claims offering fast lens but in fact the lens is fast only at the wide end of the zoom. There was a period of time in Olympus Camedia series that offered fast lens at both wide end and tele end. They are my preference also because the wide end starts from 35mm and not 28mm so that there is less distortion for portrait. After trying C2020, C3040 and C5050, I found they each have special personality by their own. The C2020 has a very cute classic style body that most people will realize it is a DC from last century and the foto it produces will surprise most people. At this early days, the maker is generous enough to include a PC socket for use with most old cheap auto flash light. The C5050 was housed in a very high quality Magneisum die cast body and equiped with many advanced useful features even by today standard e.g. raw format, real time histogram. The C5050 was built as a 2nd portable DC for professional in mind. The C3040 is some where in between but I found the foto it produced can compare favourably with C5050. All three DC take just 4 AA batteries and I found them very enery efficient. C2020 and C3040 take the already obsoleted Smart Media card while C5050 also accepts the more modern CF card or xD card.

I am wondering what is the life cycle for a folder in the context of Digital Asset Management. In line with the bucket and additive backup concept, I see a bucket in a HDD undergoes following life cycle.

• Open - The bucket is available for adding new files.  Folder in other status is always full as a backup bucket and no new files should be added to the folder.
• Meta in Review – Meta data is under review.
• Image in Review – Hash total was generated and the photo or video images are under review.
• Closed - The bucket was closed for any further update and is ready to backup to read-only media e.g. DVD.
• Re-open - The closed bucket is re-opened for updating.

Hash total is a text file kept immediately under a bucket folder listing all the file name, attribute and checksum.  Hash total is a digital signature to the bucket folder allowing to automatically detect any changes in content in the folder.

There are many software to create the digest text file for multiple files in batch. Following features help to manage to manage a large photo portfolio more effective.

• Selectively update the digest text file just for the changed or new photo only because I dont want to visually verify the other old photos again because they are too many.
• Able to perform digest verification on read only media e.g. DVD.
• Portable application so that I can perform the digest verification any where any time.
• Consider file modified attribute and file modified datetime.
• Keep should-be checksum, file attributes in digest file and show it along with actual value in the verification result.

When I have more than 20,000 photo in my collection, I start to wonder how I can ensure all of them are still being kept in the storage media properly.  All media e.g. hard disk or DVD will be aging and I may find some photos cannot be displayed properly when I open them some day in the future.  This will happen although no one can tell exactly when.  Regular data backup will not help because backing up rubbish gets rubbish.  My solution is to have the computer automatically create a digest text file containing a list of order pair of file name and checksum for the photos in my collection bucket.  And then, I visually verify these photos.  It is tricky.  Visually verifying photos and then creating digest is still not the safest.  Then, I can have the computer to automatically verify the photos regularly.  Whenever I need to copy or move the photos across partition, I also use a special tool with checksum verification to do so.

富士經典夢幻組Fujifilm made its name in high performance portable digital camera in its F series.  Fuji did it by leveraging the result of its continous R&D effort in sensor technologies and the careful balance in various factors in camera design.  I have no doubt the famous moonlight camera F31FD is qualified to be admit to my dream team.  The comparatively less well known F700 and F810 have recently joined my dream team.  Unlike F31FD, they are both capable of saving in raw format and supported by Adobe dng converter.  F700 is fitted with Super CCD SR to optimize the dynamic range while F810 provides 16:9 format.  A common characteristic of all these team members is that they all are not mega pixel blaster but still their humble 6 mega pixels sensors are producing pleasent image which can be seen from my online album http://hermanland.com/zp

Should I use raw format or jpg format when taking photograph? I had tried to explain to the beginners as most books do and still could not manage to get them understood with correct expectation. Recently, I think of a better analogy for easy explanation.  Just like raw food I got from the market, raw food is often not as tasty as the cooked food or raw format does not look as eye candy as pre-cooked jpg.  Well, some people prefer their dish cooked by P.  Here P may stand for chef from Pennisula hotel or the raw file processor from Pentax:-)  Oh, so Pennisula taste…oh, so Pentax color. If I cook the food myself, it may not taste the same as cooked by P or it may be even worse depending on my cooking skill or post processing skill to the raw file.  However, with the raw food on hand, I have the flexible to cook to whatever taste I want.