Flickr EXIF Search, Part 2

I’ve done a bit of experimentation and learned a few more keywords one can use to search for photos in flickr by their EXIF data. I have also gleaned the pattern that seems to have been used for coming up with the keywords. They appear to be abbreviations.

Keyword	Meaning	Abbreviation for	Unit
xel	minimum exposure	EXIF exposure lower limit	seconds
xeh	maximum exposure	EXIF exposure higher limit	seconds
xfl	minimum focal length	EXIF focal length lower limit	milimeters
xfh	maximum focal length	EXIF focal length higher limit	milimeters
xal	minimum aperture	EXIF aperture lower limit	f-number
xah	maximum aperture	EXIF aperture higher limit	f-number

Perhaps there’s a way to specify an exact exposure, focal length, or aperture without having to use both the lower and higher limit keywords together. If so, I haven’t found it yet.

I also haven’t yet figured out how to specify fractional exposure times (shutter speeds of less than one second). It seems to treat all decimal values less than 1 as simply 0. The text displayed above search results is not always correct. For example, when one uses xel or xeh to search for photos taken with fractional exposure times (shutter speeds of less than 1 second), the text displayed above the search results incorrectly rounds the fractional exposure times down to 0. Similarly, when one performs a search using xfl or xfh independently, the wording displayed above the search results does not correctly reflect the way these keywords function. The words shorter and longer are interposed.

Obviously, not all of the kinks have been worked out. Maybe that’s why these keywords remain undocumented. I have started a discussion thread about this in the flickr ideas group.

Flickr EXIF Search

Flickr EXIF Search, originally uploaded by blech.

Recently, I have begun to tag each of my photos with information about the camera and lens used to take the photo. It’s easy to add another tag to a batch when I’m uploading new photos. However, it’s a bit more time-consuming to go through my old photos on flickr and determine which photos were take with which lens.

Then I had a thought: the camera model used to take a photo is encoded in the photo’s EXIF data; so are the focal length, shutter speed, and aperture. The specific lens used is not included in the EXIF data, as far as I know. But using the information that is is there, it ought to be possible, I thought, to locate all the photos that were taken with a particular lens.

This led me to search for a way to locate photos on flickr based on their EXIF data. Amazingly, there's very little information out there about how to do this. I did find this one photo though, and in it one can clearly see two search parameters that don’t seem to be publicly documented by flickr:

• xfl — the maximum focal length; find photos with this focal length and shorter;

• xah — the minimum aperture (maximum f-number); find photos with this aperture and wider (this f-number and smaller).

Using these parameters, it's possible, for example, to perform the following search:
Find all of my photos tagged with climbing, with an aperture of f/2.7 or wider, and with a focal length of 50mm or shorter.

I have only one lens faster than f/2.8: my 50mm f/1.4 prime lens. So any photos returned by this search must have been taken using this lens.

Does anyone know if these and other EXIF-related search parameters are documented anywhere? I'd really like to learn more about how to perform searches using EXIF data.

Also, I would really like to know how to perform batch operations on the search results. Is there a way to add all of the results of a search to a batch in the flickr organizer? If not, there ought to be.

Weekend recap

I've just stepped out of the shower and brushed my teeth, and I'm looking forward to laying my head on my pillow in just a few minutes. I'm really tired after a fun and eventful weekend.

The original plan for Friday evening was to go climbing and dancing with Åsa R. Unfortunately, she found out at the last minute that she had to work late, so I changed my plans a bit. I skipped climbing at Klättercentret and had dinner at home instead. I was actually partly relieved to have a little time to catch my breath and wind down a bit after work. Around 10 o’clock I went down to La Isla for a bit of salsa dancing. Some other friends who had planned to show up never did, and the place was really dead. Lots of the folks from the Stockholm salsa dancing crowd were on a Baltic cruise this past weekend, so maybe that's why the place was so empty. Elin was there with her new dance partner Paolo, and I danced a few dances with her. I also saw Niklas and Suzanne there — two of the folks from last weekend’s Sailsalsa after-party. After a while I saw that Janaki was there with some of her friends. We danced a bit, but after just a few dances, the D.J. started playing only reggaeton and disco music. We decided to try another club, Mojito, instead.

Mojito was packed, but not as crowded as the last time I was there. Plus, with the cooler weather, one could actually breathe. It wasn't a sauna this time, but it was still hot and sweaty. We danced until closing time. It's fun to dance at different clubs because each one has its own crowd. The crowd at Mojito is definitely Cuban and Central/South American: much more relaxed and easy-going than La Isla, but also a bit less serious about dancing.

Saturday I spent most of the day just lounging around and relaxing. I went outside for a while to take some photos of the flowers in Vibeka’s garden. I had mixed success because of the clouds that obscured the sun much of the afternoon.

In the evening I took the commuter train out to Johan K.’s parents’ place in Spånga for his 28th birthday party. I met some nice folks at the party, including Tennessee native and MIT graduate Katy, who moved to Stockholm two weeks ago to begin her post-doctorate work — something related to finance and mathematics. Inger and Eva also showed up after a while. It was through Inger (and Elias) that I met Johan three years ago. A few hours into the party, a bunch of folks went down to the basement playroom to compete in a dance-based video game. One plays by dancing around on a mat on the floor that's connected to the game machine (a Playstation 2). It was a lot of fun, and Johan’s sister was the best of all of us. I dind’t realize how late it was getting, and before I knew it, the time was after 3 in the morning. The trains had long since stopped running, so I called a cab to take me home. During the drive home I chatted with the friendly driver, a man from the Kurdish region of Iran who has lived in Sweden for 30 years. I finally got to bed around 4.

Sunday morning I was awakened around 9:30 by a phone call from Åsa B., reminding me that the “IBM Day” at Gröna Lund was about to begin. IBM reserved the amusement park between 10 in the morning and midday, and bought tickets for all of its Stockholm employees who wanted to come. I managed to make my way down to the entrance on Djurgården just after noon. Once inside the park, I met up with Åsa and Patric and went on a few rides with them. We rode the blue roller coaster and then rammed into one another in the bumper cars. Åsa and Patric had been in the park riding the rides since just after 10, so after those two rides, they went home. Left to amuse myself, I rode the roller coaster again, and then rode the fun catapult tower that shoots you up to the top of the tower (sort of like an inverted free-fall tower). It was quite cool outside, and after a while it started to rain. The cold weather and a slight hangover discouraged me from riding any more rides, so I took out my camera and started taking photos. I took a few photos of people and the rides; but mostly I photographed the park’s nice flower arrangements. I was reminded then that I had met a girl on the subway a few months ago who told me she worked maintaining the flowers and plants at Gröna Lund. I can't remember her name, but I do remember that she was friendly. The flowers were lovely, so she must be doing her job. I'll post some of those photos soon, by the way. I also met a fellow Nikon SLR owner (and soon-to-be Mac owner) who was there taking photos of her friends. Her pictures from today are already online, so you can take a look at them to see what the weather was like today.

After a couple of hours at Gröna Lund, I went down to Karbin for a bit of climbing. I had expected to see one friend there, but she never showed up. Instead though, I ran into lots of other friends, including Sara, Elin, Emma and Ewa. I wasn't really in top form, so instead of climbing intensely, I make more of an effort to get some good climbing photos. I went up to the top of the wall, tied in with a sling, and took a bunch of photos pointing down as my friends climbed up. With the help of a new friend named Joachim, I also got some photos of myself. Also climbing with us was another new friend named Jessica. She comes from Canada, and despite being relatively new to climbing is very good at it.

The rain was still coming down outside when I walked across the street to the bus stop. As I sat and waited for the bus to Liljeholmen, another fellow climbing walked up and sat down. We started talking and I learned that his named was Alexander. It turns out that he has an American fiancée and plans to move to Denver soon.

When I arrived home around nine P.M., The Bourne Supremacy was just starting on TV. I watched it on-and-off while answering emails and fixing dinner. That film is pretty good: better than the third, but not as good as the first.

Well, that’s it. That was my weekend. Lots of activities and very little sleep. Of corse spending half an hour writing a blog entry doesn’t help the balance of my sleep account very much, now does it? But what are you going to do? Over and out from Stockholm.

New photo set: Portraits

I have begun to reorganize my photo sets, taking advantage of the new “collections” feature in flickr, and grouping most of my photo sets into collections based on kind or content.

My most recent change is the addition of a photo collection for artistic photos — in other words, photos that have more artistic than informational value, and I hope are appealing as more than mere what's-Michael-been-up-to reportage.

Portraits is a new set in this collection. I think some of them are quite good, but I'll let you judge for yourself.

My next task it to go back through the set and remove photos that are either not strictly portraits in the classic sense of the word, are are simply uninspiring. My intention for the sets in the artistic collection is that these sets contain only aesthetically pleasing photos.

Searching for multiple criteria in Flickr

When I began posting photos to Flickr a few months ago, I was faced with a problem: how does one link to a gallery of photos that match a certain set of search criteria? I never quite figured it out, and I resorted to creating event-specific tags. For example, the tag container_2007.03.04 might represent the evening of salsa dancing at Container last night.

Well today I finally figured out how to do what I really want to do. Instead of creating a separate tag for each event, I can simply construct a URL that performs a dynamic search for photos that match multiple criteria. For example, the URL

http://www.flickr.com/search/?q=container+AND+salsa&d=taken-20070304-20070305;&z=t&w=44124463651%40N01&m=tags

displays the same collection of photos, assuming the photos are tagged with container and salsa. I prefer using generic tags so I'm in the process of removing the old event-specific tags and replacing links with dynamic queries like the one above.

The only drawback I have found to this way of linking to my photos is that the search results page displays advertisements from Yahoo. I guess ad-free search pages aren't included with my Flickr Pro membership.

BloggerBot is dead. Long live BloggerBot!

Today, BloggerBot was deactivated. It has been widely known for a while that the end was near, but BloggerBot's final demise is nonetheless disappointing.

Since 2004, I have posted photos to my weblogs using Hello and BloggerBot. The interface made quick work of the job of uploading a series of photos and providing a short caption of each one.

Nothing Google has provided offers the same simple way of uploading photos to a blog. For this reason, I have stopped posting many photos to my blogs, and have started posting them to flickr instead.

BloggerBot was a useful tool, and I'll miss it. I hope the good folks at Google are working to make improvements the remaining systems, so that uploading photos is again as easy as it was with BloggerBot.