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.
16.7.09
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.
28.4.09
First holidays with the G1
I remember I didn't write anything about my Easter holidays yet. I went skiing in the Italian Dolomites, to a nice little town in the province of Trento named Moena. Its in the middle of Fassa Valley, a valley in the region of Trentino-Alto Adige where people speak an ancient Rhaeto-Romance language called Ladin. I know this region since I was a kid, we used to go skiing there with all of our family, quite regularly for more than ten years. Moena lies at the foot of the Cantinaccio mountain range, home to the legendary dwarven king Laurin, who was said to having kept a garden of beautiful roses high up near the mountain top. Stories tell he fell in love with a beautiful woman and abducted her. He was defeated by the womans brother and a band of brave knights and taken away into custody, but as a last action he put a ban on his rose garden turning it invisible day and night. But he forgot about dusk, which is not day or night and thus you can sometimes see the mountains glow red of roses in the last rays of daylight when the time is right. So they say.
Easter was late this year but reportedly it had been snowing heavily throughout most of March and April and the conditions were said to be quite good so I took the chance to go there and spend a week skiing and trying my new camera equipment. I had recently bought a Lowe Pro Slingshot 200 back pack that is big enough to hold all my gear, the G1, 14-45, 45-200 and the Canon FD 50 1.4 lens, together with a small tripod and cables, filters, charger, etc. I didn't take the Metz flashgun with me, I have found that it's a part of my equipment I almost never use and since it adds considerable weight I left it at home. I didn't miss it.
I wasn't going there alone. We were a group of around 15 people and we had rented a house for the whole group. A couple of them I knew already from earlier trips to Moena, some of them even from the time I went there together with my parents and brother. The area of Trevalli (Three Valleys) offers quite a number of skiing opportunities. If you have a car, the selection of resorts within 20 minutes travel distance is quite impressive. The image to the left was taken from the top of Col Margherita, which is part of the San Pellegrino skiing resort. Looking at the pictures its hard to believe it was already beginning of April. Not often have I seen this amount of snow that late. However, the warmth of the approaching Spring time was busy melting the snow and even though there was lots of it, its quality degraded massively during the day. So we got up early every day and tried to be on the ski piste soon. That worked rather well, by the time the snow turned soft around 3pm we usually had enough for the day and enough time left to chill, drinking marvelous Italian coffee and eating ice cream.
All the time I carried the Slingshot pack on my back. It was working really well on the piste, I almost didn't feel the weight of the gear and when it was time to enter the lift I could just swing it around from back to front and sit down comfortably. My sun glasses turned out to be a bigger problem, I had to take them off for taking pictures together with my gloves. The viewfinder worked pretty well under the bright sun, I just had to shield it a bit with my hand. The LCD turned out to be mostly useless. I tried to take photos with all the lenses I had, most of them with the 14-45, but some with the 45-200 as well. Sometimes I used a polarizer filter to improve the sky colors and cut down the haze a bit, but still I had to post process most of the images to correct white balance and levels. I used only digikam for raw development and corrections and it handled the task pretty well. I had also taken the MSI U100 netbook with me which allowed me to download the images every evening and inspect them.I've uploaded a selection of images taken during my stay to Flickr, there's a set named Dolomites. All in all I'm quite satisfied with how the G1 performed. The only thing I'd have wanted is a bit more of dynamic range. One stop more might have made a difference in some situations.
26.4.09
Old Gear, too
Today a big jumble sale of photo equipment was held at a university facility, it takes place only once a year and it was the first time I went there. It was quite amazing, the mass of gear for sale was huge. Wide selection of stuff from all old and recent camera makers. The selection of Canon FD lenses was not too rich, though.
Still, I was quite successful and got a 28mm f/2.8 for very little money and a 50mm f/3.5 macro lens in very good condition for considerably less than the cheapest ebay offer.
I was tempted to buy a 24mm f/2 and had another good offer for a 24mm f/2.8, but the difference in speed and field of view was too little against the 28mm I already had in my bag and I declined. Instead I took the 50mm f/3.5 macro, I think it will be nice for flower shots and might work as a portrait lens as well.
The 28mm is a particularly nice lens. It's very light and the effective focal length of 56mm is close to a typical film standard prime. I think I'll like it. The 50mm macro is a bit long physically, but also quite light. Not something to have on the camera all the time, but still something to have in your photo bag.
Some first images with both lenses can be found in my flickr photo stream.
Still, I was quite successful and got a 28mm f/2.8 for very little money and a 50mm f/3.5 macro lens in very good condition for considerably less than the cheapest ebay offer.
I was tempted to buy a 24mm f/2 and had another good offer for a 24mm f/2.8, but the difference in speed and field of view was too little against the 28mm I already had in my bag and I declined. Instead I took the 50mm f/3.5 macro, I think it will be nice for flower shots and might work as a portrait lens as well.
The 28mm is a particularly nice lens. It's very light and the effective focal length of 56mm is close to a typical film standard prime. I think I'll like it. The 50mm macro is a bit long physically, but also quite light. Not something to have on the camera all the time, but still something to have in your photo bag.
Some first images with both lenses can be found in my flickr photo stream.
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