Google announces their own public DNS now. Some seem to think it's a good move and a fundamental threat to ISPs who are diluting the neutrality of the net. However, I tend to side with the conspirationalists who see it as an attempt of Google to gather even more information about what people do online.
Using the Google DNS you basically allow them insight into any connection your PC performs while it is online. Not about the data exchanged, but at least about what other computers you are connecting to, and not just during web browsing, but also email, instant messaging, chatting, peer-to-peer networking and so forth.
Of course my ISP provides their own DNS and uplink routers are normally configured to use the ISP DNS servers, but I bet Google's Chrome OS will by default use Googles DNS. Guess what I'm not going to use on my private machines.
Now, unfortunately ISPs are known to tamper with DNS queries of their users. If you ever tried to surf a non-existing site you probably found your browser displaying some "navigation aiding" by courtesy of your friendly Internet provider. While meant to be helpful towards their users it bears a threat as well. There you have an infrastructure which is specifically built to intercept connection attempts. While I can't say I actually appreciate this, the way Google harvests data is seriously creeping me out just as much.
9.11.09
Some photos from the summer
I only recently found time to process and upload some photos I took during our summer holiday this year. Instead of going abroad we decided to travel Germany, there are quite a few places we've never been. This year we went East, visiting Thuringia and Saxony. I've uploaded a selection to Flickr, with more to come. Enjoy today some impressions collected visiting Dresden, which marked the end point of our journey.
16.7.09
Control is an illusion?
In a recent interview with the Digital Photography Review web magazine a Nokia representative talks about convergence devices like the N86 mobile phone incorporating an 8MP digital still camera and aiming to replace digital compact cameras in many peoples' pockets. Read the story here.
Seemingly unrelated, The Register has an article about a provider in the United Arab Emirates pushing a trojan horse program as a software update to their customers Blackberry smart phones. The sting was only accidentally discovered and if anything can be learned from that, it is that stuff like that is not just overheated imagination of a few conspiracy theorists but happening right now under our very eyes.
This got me thinking. Do I really want all those features crammed into a connected device I have no control over? Each and every feature requires me to provide more, sensitive information. Phone books are no longer just phone books but store email and postal addresses of my contacts. browsers store web site credentials, Ebay, not to mention PayPal accounts. All my data under the reign of a software that can be changed at any time, without me even noticing.
I may want my camera be a camera, and my mobile phone be just that and nothing else.
Seemingly unrelated, The Register has an article about a provider in the United Arab Emirates pushing a trojan horse program as a software update to their customers Blackberry smart phones. The sting was only accidentally discovered and if anything can be learned from that, it is that stuff like that is not just overheated imagination of a few conspiracy theorists but happening right now under our very eyes.
This got me thinking. Do I really want all those features crammed into a connected device I have no control over? Each and every feature requires me to provide more, sensitive information. Phone books are no longer just phone books but store email and postal addresses of my contacts. browsers store web site credentials, Ebay, not to mention PayPal accounts. All my data under the reign of a software that can be changed at any time, without me even noticing.
I may want my camera be a camera, and my mobile phone be just that and nothing else.
1.7.09
Canon vs Tokina 135mm lens shoot out
A couple of days ago I acquired an old Canon A1 SLR camera. Someone was selling off old photo equipment on Ebay and so with the camera came a small collection of four lenses. One of them is a Tokina 135mm f2.8 telephoto. It's quite an impressive item, looking much sturdier mechanically than its Canon FD counterpart. It's made of all aluminium, even the aperture ring is made of metal. It feels quite heavy in your hand and appears to have been well treated since there is no apparent sign of wear. Since I also own the Canon lens, I started wondering which of the two to sell. Casual shooting with both lenses on the G1 didn't reveal major differences in image quality so I did a series of shots under more challenging conditions.
The following photos show performance of both lenses while taking images of a church in my home town against the bright sky before sunset. The sun is hidden behind a cloud layer just outside to the right of the frame on the G1, on a 35mm film camera it would still be inside the frame.
The photos taken with the Tokina are always on the left side. They start at f8 and go up to f2.8, the maximum aperture for both. The lenses feature a built-in hood, it was used while taking the photos but of course for a factor-two crop sensor it's not deep enough. The images were taken as RAW files and then developed without any sharpening or other corrections applied. They were downscaled for presentation and 100% crops of two interesting areas patched on.
As you can see, at f8 there is not much difference between both lenses. If you look at the 100% crops, there is a slight advantage for the Canon, but it's not obvious. There is a difference in color tone, but I cannot say if its a difference of the lens or just subtle changes in the lighting conditions.
At f5.6 the difference is more noticeable. While the Canon lens shows almost no degradation in sharpness and contrast, the photo taken with the Tokina is becoming a little soft with a very slight amount of CA, but it's still pretty good.
The trend continues at f4, the gap between Tokina and Canon is getting wider. The Canon now starts to show a little softness and a bit of CA, but its overall still pretty good.
At f2.8, the Tokina shows a significant loss of contrast and increased softness. Color seams appear around back-lit areas. The Canon has also lost some of the sharpness and contrast it displays at smaller apertures, but its a lot better than its Tokina counterpart.
Summing up, I found the Tokina lens to be performing quite well under most conditions. A challenging environment like strong light sources just outside of the frame requires stopping down to f4 or f5.6 for good image quality. The Canon 135mm however proves to be an excellent lens with good results even wide open.
The following photos show performance of both lenses while taking images of a church in my home town against the bright sky before sunset. The sun is hidden behind a cloud layer just outside to the right of the frame on the G1, on a 35mm film camera it would still be inside the frame.
The photos taken with the Tokina are always on the left side. They start at f8 and go up to f2.8, the maximum aperture for both. The lenses feature a built-in hood, it was used while taking the photos but of course for a factor-two crop sensor it's not deep enough. The images were taken as RAW files and then developed without any sharpening or other corrections applied. They were downscaled for presentation and 100% crops of two interesting areas patched on.
Tokina f8 | Canon f8 |
Tokina f5.6 | Canon f5.6 |
Tokina f4 | Canon f4 |
Tokina f2.8 | Canon f2.8 |
Summing up, I found the Tokina lens to be performing quite well under most conditions. A challenging environment like strong light sources just outside of the frame requires stopping down to f4 or f5.6 for good image quality. The Canon 135mm however proves to be an excellent lens with good results even wide open.
7.5.09
Digikam hacking
Since a few days I'm officially a contributor to digikam! I even got my old KDE SVN account reactivated and updated and so I can directly contribute code to the project. It started with a bug in the lens correction plug-in I fixed that turned into developing a method to access sub-pixel image data. Currently I'm working on an additional tool for digikam's batch queue manager. This nice feature is particularly helpful for people who need to apply a series of operations to a large number of images at a time.
I'm developing a batch tool to sharpen images, for example after resizing them for print. I found that these two operations, resizing and then sharpening, are a somewhat common constant in my work flow. Usually, I shoot RAW images, import them into digikam directly, then apply white balance, tone curve corrections and sometimes input sharpening. There is little to be automatized there because each image needs different treatment. After this first step I save the post processed images as TIFF. Then, depending on what I do with them, I resize them differently, e.g. 1024x768 for Flickr, 1600x1200 for small prints, etc, and convert to JPEG. Downsampling tends to soften the images, so the final processing step is always a slight sharpen filter.
To demonstrate the effect, take a look at the following two images. The first one was just resized to 1600x1200 pixels, the second one was treated with an Unsharp Mask filter after resizing. It looks more crisp. Click on the images to view them in original size for the full effect.
I'm developing a batch tool to sharpen images, for example after resizing them for print. I found that these two operations, resizing and then sharpening, are a somewhat common constant in my work flow. Usually, I shoot RAW images, import them into digikam directly, then apply white balance, tone curve corrections and sometimes input sharpening. There is little to be automatized there because each image needs different treatment. After this first step I save the post processed images as TIFF. Then, depending on what I do with them, I resize them differently, e.g. 1024x768 for Flickr, 1600x1200 for small prints, etc, and convert to JPEG. Downsampling tends to soften the images, so the final processing step is always a slight sharpen filter.
To demonstrate the effect, take a look at the following two images. The first one was just resized to 1600x1200 pixels, the second one was treated with an Unsharp Mask filter after resizing. It looks more crisp. Click on the images to view them in original size for the full effect.
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