I spent last weekend at the Brussels Tango Festival, mostly taking pictures of people dancing. Because of the lack of light that is typical for tango events, I had bought a Canon 50mm f/1.8 lens online one week before. First at Pixmania, but because they couldn’t deliver fast enough (product not in stock), I cancelled and ordered at Foto Konijnenberg. I expected the package to be delivered in a couple of days. When I didn’t see any sign of delivery and the track&trace URL didn’t work, I contacted Foto Konijnenberg (very friendly and correct customer support, by the way) to ask what was happening. Apparently the transport company had been at my door twice, did however not leave any message, took the package back and at that moment no one could tell me where the package was. We’re now 2 weeks after purchase and still at the same stage: my lens is somewhere in the purgatory between vendor and buyer but the transport company (TNT/DPD) has no clue where.
Apart from the fact that the transporter screwed up their tracking of the package, the whole process of showing up at closed doors and going back seems so inefficient. It’s like so much effort has been spent to smoothen out the process of purchasing online, but the physical delivery still works basically the same as twenty years ago, eventhough the drivers now have wireless devices and you have to sign on an electronic sensor.
Let’s describe how I would have preferred to have my goods delivered:
Package Delivery 2.0
Continue reading ‘Package Delivery 2.0′
Yesterday I reached 100.000 views on my Flickr account. Using the numbers above, that translates in almost 32 views on average for each picture. But of course, my Flickr photo collection has power law (big head/long tail) distribution. Let’s dive into the head.
Most viewed pictures
The top five of my most viewed pictures are:
5787 views and also a favourite of 29 people. My not-so-bad
Web 2.0 overview from the early days of the meme (Sep 2005)
5482 views. I have no idea where those came from.
Continue reading ‘100.000 Flickr views’
If you take a low-res picture, and you want to blow it up to a higher size, there are different algorithms to do the calculation of all those new pixels. I talked about this earlier in “How to upsize an image“. I went a bit further now and took a 100×100 pixels detail of a Roos Van Acker picture by Filip Naudts and enlarged it five times: to 500×500. The tool I use, Irfanview, has 6 algorithms to do resize:
Contrary to what I expected, it was not the Lanczos filter (slowest and ‘best’) that gave the best results, but the B-spline algorithm that’s supposedly a bit worse. With Lanczos you get an rastering effect (check her hair), with B-spline it’s more even.
Continue reading ‘To upsize a picture, use the B-spline algorithm’
French hospitality #1
I’ve just spent a great weekend with the family in France. A couple from Antwerp has restored a “gentilhommière” (small castle) in Le Thurel (Picardie) as a gite d’etappe and turned it into a pleasant bed-and-breakfast!
Long walks on the beach, excellent food and abundance of wine. Splendid!
Continue reading ‘French hospitality’
Lots of people have been taking pictures on New Year and this clearly shows in the stats of incoming pictures at two major photo hosting sites: Flickr and Smugmug.
Flickr reached a peak of nearly 100.000 pictures/hour (97.1 k#/h) and Smugmug a quarter of that (22.7 k#/h). That is 50% to 100% more than regular days.
Flickr
(about 60 of those are mine)
Smugmug
(none of mine)
What’s the value of more megapixels? Is 10 megapixels better than 5? Here are some articles stating the opposite:
On the show, we did a test. We blew up a photograph to 16 x 24 inches at a professional photo lab. One print had 13-megapixel resolution; one had 8; the third had 5. Same exact photo, down-rezzed twice, all three printed at the same poster size. I wanted to hang them all on a wall in Times Square and challenge passersby to see if they could tell the difference.
(…)
I’m telling you, there was NO DIFFERENCE.
The Truth About Digital Cameras (NYT)
Megapixel apples and oranges
A 5-megapixel image that was created by down-sampling a 13 megapixel original is not the same as a 5-megapixel original. Why?
Well, let’s take a look at how a digital camera CCD sensor works. Natively the sensor is color-agnostic: pixels only measure light, not color. So the chip can only do greyscale images. A smart guy from Eastman-Kodak, Dr. Bryce E. Bayer, has however found a way to add color-sensitivity, by adding an RGB color filter array (the Bayer filter). Each pixel has a filter in front of it that lets through either the Red, Green of Blue light. Since the human eye is most sensitive to green, 50% of all pixels measure green, 25% do red and another 25% blue. A 5-megapixel image from the sensor is really a 2.5 MP green image, a 1.25 MP red and a 1.25 MP blue image, the three of them almost overlapping (1 pixel off). This is how the image is stored in RAW format. Each such pixel has a value between 0 and 4096 (12 bits). To convert it to a full-color image (8-bit value for each color R-G-B, so 24 bits for each pixel), the missing colors for each pixel are derived from the neighbouring pixels (aka demosaicing). E.g. a Red pixel has the exact value for the colour red, gets the green component from 4 neighbouring green pixels and the blue one from 2 neighbouring pixels. (More advanced algorithms exist) This gives some false colors (’artefacts’) at sharp edges. Let’s simulate this with a pure black/white border:
A pixel in a native 5-megapixel JPG image is based on 5 to 7 pixels of RAW color info. A pixel in a 5-megapixel camera that was downsampled from a 13MP image, gets its color info from roughly 20 pixels of original info. So the colors are more correct (provided the original picture was good quality, of course). Also, the color artefacts around sharp edges are much thinner so that they may almost disappear after the resizing.
My point being: printing out a resized 5MP picture is not an honest comparison.
Continue reading ‘Megapixel myth nuances’
While writing my previous post on the Canon 400D camera, I came across a site that advertises one such camera at €380 – with ‘free international shipping’. The 30D they sell for €480 and the professional 5D for €1400. At a respectable online shop like Foto Konijnenberg, those prices are €739, €1199 and €3139, respectively. So is this too good to be true? Yes indeed, it is!
Uk-based(?) webstore DexDigital.co.uk (gone, but resurrected as MobiTeh.co.uk, EastElectronics.co.uk, Gonex.co.uk, AnviDirect.co.uk, cxMusic.co.uk, wMusic.co.uk, aigars.co.uk, orvisinc.co.uk and StarkDigital.co.uk) has given this concept a new, and far more sinister, twist. Read on to learn how the scam works.
(from heim.ifi.uio.no)
Continue reading ‘Starkdigital: fake web shop’
The new Digital Rebel
It might be me, but it’s like everyone around me is buying the new Canon 400D. OK, that’s exaggerated, but I’ve spotted at least 2 people I know per week in this last month.
At €739 for a 10 megapixel digital SLR, it’s a sweet deal. The ‘old’ 350D (now €649) was already a really nice camera, but the added resolution (10 MP instead of 8 MP), the EOS Integrated Cleaning System and certainly the larger screen will probably make this one even a bigger best-seller. Which means I will have to cope with a lot of “Yours has only 8 megapixels? Mine has 10!” For the record: that doesn’t matter!
We blew up a photograph to 16 x 24 inches at a professional photo lab. One print had 13-megapixel resolution; one had 8; the third had 5. Same exact photo, down-rezzed twice, all three printed at the same poster size. (…) I’m telling you, there was NO DIFFERENCE.
Continue reading ‘The popular Canon 400D’
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