I’m not going to delete it completely, but I don’t intend to maintain it anymore. To remove the burden, I will just move the content back to WordPress.com, and let it stay there. I don’t think the images will survive the moving process as they are scattered all over the place. Some are in the wordpresss database, some are linked externally, and some are just stored elsewhere on my own server. Some of them will probably disappear as I start to clean things up.

The new URL will be (as it used to be a couple of years back) http://lentic.wordpress.com/, but don’t bother putting it in you feed reader, it’s just kept for reference.

As you may already know, I have made a transition to my Norwegian blog (http://speilbildet.no), but there are other things happening as well.

My son is getting older every day. He’s closing in on 7 months now, and he has already started to stand up, supporting himself on tables or anything I can get a hold on. He has even started to take a couple of steps while pushing a box in front of him. Needless to say there are intense and fun times right now.

In addition to that, I started in my new job 4 weeks ago. I have more fun at work than ever before, and I’m excited to go to work every morning now. One side effect of this is that I am more spend in the evening, resulting in less photography at the moment. I guess I will find time for more photography when the dust settles.

A fairly new one shot with my Pentax K-7 and the DA70mm Ltd.

If you use YouTube, this plugin also gives you the choice of viewing the videos in high quality H264, HD format instead of the crappy default format (which is flash based).

You can also read more at AppleInsider.

I can live with that.

I got another comment to my “Fixing a broken LightRoom catalog” post. It is good to see that someone actually find some of the information useful.

Just an image to prove that I’m still here.

So, go into the catalog settings and uncheck the “Automatically write changes into XMP” option inside the “Metadata” tab. You should also go into the “View Options” under the “View” menu, and tick off the “Unsaved Metadata” checkbox. That way you will get a small arrow on each photo that contains unsaved metadata. Every once in a while, and at least every time you quit the session, select those photos and hit Cmd-S. You will not lose work even if you don’t save, but then the metadata is only stored in the LR database file, and not as part of the image file. If the metadata is stored in the image files, you will get back everything if you reimport them into a new catalog, which is good if the lightroom catalog gets corrupted.

Contrast based auto focus

To start with contrast based auto focus. This type of system is most commonly used in compact cameras, and on some dSLR’s when the Live View function is used. It uses the actual imaging sensor to determine focus, and here is how it works:

1. It shoots a series of images at different focus settings.
2. For each of these images, it will determine how  much contrast there is in the designated focus areas.
3. It selects the image with the most contrast, and reset the focus to the value it used to capture this image.

This process is relatively slow since the camera must take a large number of shots and process them before finding the focus. On many cameras you can observe this if you look at the lens while trying to focus. It will cycle focus from one endpoint to the other before it snaps back to somewhere in between which hopefully is the right focus setting.

A major drawback with this kind of focus is that the camera has no way of predicting if the focus is in front of, or back of the current setting. It must just try in one direction and hope that it is right, and if not, it must go the other way.

Phase detection auto focus

This type of auto focus works kind of like the good old split prism in the days of manual focus. The focus system will take a part of the light coming from one side of lens and project it on one sensor, and a part of the light coming from the opposite side of the lens and project it on another sensor. These sensors are dedicated AF sensors, and are usually formed as narrow strips. When the image is in focus, the two images are perfectly aligned, but they will get more and more misaligned as the system gets more and more out of focus. Just like the split prism, all the AF system has to do is to rotate the focus until the two images are aligned.

A major benefit with this type of AF is that it can predict which way the focus shall be turned. Not only that, but it can even predict how far it shall be turned. This is accomplished by detecting to which side the misalignment is, and how much the images are off.

Here is a short drill down how it works:

1. The AF sensor detects the direction and amount of misalignment.
2. Based on the information about the lens, if predicts how far the focus must be turned.
3. The focus is then adjusted accordingly (focus is not measured when this happens since the focus changes too fast).
4. When the focus motor stops, a new measurement is performed. If the focus is not perfect the drill (1 through 3) is performed over again, but now the adjustments are much smaller, and therefor more precise.
5. This goes on until the focus is good, or the system times out because it is unable to find focus.

The big misconception is that this system optimizes contrast, when in fact it correlates two one-dimensional images. When the contrast based system relies on a sharp edge to focus, this system only need some sort of recognizable pattern. In theory, it should be able to focus on a smooth gradient that goes along the focus sensor.

Here is an illustration by Canon (go to the bottom of the page).

And here is the Wikipedia article.

So, this is an overview of my understanding of these systems. If anyone more knowledgeable than me finds this to be wrong, please write me a comment.

I just came across a really neat little application. It’s called jDarkRoom, but even if the name suggest some sort of relation to photography, there is none. It’s a very simple text editor with a rather unique feature.

When you start jDarkRoom for the first time, it will fill the entire screen with black, removing all menus, task bars, docks and everything. When you start to write, green text will apear using a simple monospace font. The idea is to minimize the number of distractions while you write. It is also the most basic text editor you’ll ever find, featuring only the basic functions like open/save, cut and paste, and search functions. Some may consider this a drawback, but for me it is all I ever want.

When I write a piece of text, instead of using a word processor (like Word or OOWriter), I prefer a text editor for its pure simplicity. I will usually start to capture the content, adding formatting, graphics and tables later. A word processor distracts me, and I start to worry about formatting and figures as I write, which breaks the flow. When I’m more or less finished writing, I will paste it into a real word processor for spell checking, layout and formatting.

Another good reason why I don’t like writing in word processors are the tendency they have to pause everything for some background task. Not too seldom, I find that I have written more than a sentence before the word processor wakes up and start the catching up. The basic text editor is snappy.

This editor is not suitable for coding, but it will probably be my first choice for capturing ordinary text.

You’ll find it here (http://www.codealchemists.com/jdarkroom/), it is written in Java, available for all platforms, and it’s free. I’ve tried it on both Mac and WinXP, and works fine.

PS.

I may slow down on posting here, but I don’t intend to shut it down completely.

Also, I won’t deny that having a 2 month old son is putting some restrictions on the web activities, but not as much as I would have expected. He’s really very nice, sleeps well at night.

Anyway, if you read Norwegian you can stop by http://speilbildet.no

If not, just keep me in your RSS reader, who knows when I find the time to post something.

Now they get som google attention again with the release of “Angels and Demons”. Ambigrams are a central part of the plot in that book, and in the film also I presume. The book sucked so hard you won’t believe it, so it shouldn’t be too hard to make the movie better. I acutally enjoyed reading “The daVinci Code”, but “Angels and Demons” was just crap.

Anyway, funny how a movie affects what people googles, and that the stats pick up these things.

While my Canon zooms, namely the 70-200 f/4L IS, the 24-105 f/4L IS and the 17-40 f/4L are magnificent, they are also huge. That’s a big problem on the street, but even while doing nature photography it’s a problem. Due to some back problems, I am reluctant to carry more than one of those lenses, and even then the setup is heavy on my sholder. Im really thinking more and more of the Pentax gear. So far the starting setup would look something like this.

• K7 body
• The kit zoom for family snaps (doesn’t really add much cost)
• DA 21mm f/3.2
• DA 35mm f/28 Macro
• DA 70mm f/2.4

After that, some potential candidates would be

• DA 15mm f/4
• DA* 50-135mm f/4
• DA* 16-50mm f/4
• DA* 55mm f/1.4

It is always good to have a zoom or two, and the DA* lenses are weather sealed as well, so there is an added benefit.

Anyway, here is some of the pictures from today. Remember, click on them to see a bigger version.

Oh boy how that made a difference. The computer just became so snappy now. Startup, login and application startup is so much faster, and I don’t have to listen to that harddisk sound all the time. I still have ordinary drives for my image files and all the other data I store, as well as for the TimeMachine drives, but the system and applications are on the SSD drive. Below is a table of different operations using the new and the old drive. And by the way, the old boot drive was the standard 320GB drive that came with the computer. It’s a Western Digital 7200rpm drive.

This is not a very accurate or scientific test. I only did it once for each drive, and it is kind of difficult to determine when some operations are finished, but it gives an indication of how it went.

The subjective impression is that things suddenly happens instantly. The icons in the dock hardly gets to bounce when an application is launched. All this joy is of course a result of the close to zero access time on these disks. There is no speedup on cpu intensive operations, like LightRoom development operations or Photoshop work, but all the small daily tasks suddenly became much more enjoyable.

Just a note on the OCZ drive. The Vertix has got some very good reviews, but don’t mix it up with the Apex model. Even if the Apex drive seems to give faster read and write speed, the controller circuit does not handle large amounts of small files very well. The performance drop in such cases are dramatic. The Vertex has a different controller with a cache, which handles this very well.

The LX was the nicest (is that a word??) camera I’ve ever owned and used. It was small and fairly light. It had moderate weather sealing, and very robust. The auto exposure was very unique, used only by Pentax and Olympus, with TTL reading for ordinary exposures as well as flash. The meter measured the light that reflected off the film during exposure, and closed the shutter when it was enough. Really good for low light shots. It also had a very precise film advance mechanism that enabled you wo rewind to a previous shot on the roll and do a second exposure. On lots of other cameras you could see the spacing between the frames vary, but not on the LX. The handeling was excellent, and the controls was very traditional. It was a camera I could use very fast. Unfortunately I sold it off during my student days. I needed the money to buy into a sailplane (yes, a real plane you sit in and fly, but without an engine).

When I started my quest into digital photography, I instinctively headed over to the Pentax shelves, but at the time it seemed like Pentax had wandered into the dark age with both their dSLRs and their lenses. I went for Canon instead. My Canon gear have seen a lot of use. The 5D is a work horse that produces really nice images, and the lenses are stellar, which shouldn’t come as a surprise as I went for L-glass. But there are some issues. As much as I want to like it, the ergonomics of the knobs and buttons are not quite fit for me. I just can’t get used to it. Also, the gear is very bulky. The lenses, apart from being big and heavy, has only one slight disadvantage. The multicoating is not as good as Pentax SMC. Even the old glass I used to have behaved better when pointed at the sun than the expensive modern Canon glass I own.

Oh, and the viewfinders; The Canon 5D has a very good reputation for a big and bright viewfinder these days. A couple of years back, I found my old Pentax Mz5, which I didn’t sell for some reason, and I was shocked when I looked through it. the Mz5 is a very small camera, smaller than all of todays “small” dSLRs, more like the Panasonic G1. The viewfinder, on the other hand was way bigger and brighter than the Canon 5D. I had a comparable lens on it, a 28-70 f/4 vs. EF24-105 f/4. The prism house was so much smaller to look at than on the Canon, and Pentax also managed to squeeze in a pop up flash as well. But the view …… aaah .. somthing to kill for. And worth mentioning, this was the low end model at the time. I had about the same viewfinder experience when I looked through a Canon 1Ds mkIII the other day, but this camera was also equipped with the 85mm f/1.2 lens.

Well, a couple of years has passed by, and Pentax has found their way back into the sun. The lens lineup is better than ever, and the newly announced K7 seems like a real killer. I’m going to be first in line to try it out when it hit the stores this summer. The K7 with its weather sealing, small size and 100% viewfinder. As much as I like my Canon lenses, I will definitely consider the K7 when it comes. Combine it with a 16-50mm f/2.8 and a 50-135mm/f2.8, it should be a good replacement for my Canon gear. Add the 55mm f1.4 and the 21mm as well, and it may well be a killer kit.

Good thing the camera isn’t in the stores yet so I’m forced to think it through.

If I’m going down that path, maybe I should start with the K7 and only the two mentioned primes. It could be healthy for my photography.