Идва ли пролетта по-късно ?

Източник на данните: stringmeteo.com

За графиката са взети средномесечните температури за месец март и месец април за миналите два 20 годишни периода 1971-1990, 1991-2010. За март средномесечните температури за се повишили спрямо предходния период с 0.1 C, а за април със цели 0.3 C.

Ако приемем, че пролетта в нашето съзнание идва март-април и е свързана основно с повишаването на температурите и произхождащите от това промени в природата, пролетта по-скоро идва по-рано, отколкото по-късно. Защо тогава много Софиянци твърдят, че зимите напоследък са станали по-меки, но пролетта закъснява?

Аз намирам две възможни обяснения за това. Първо ако наистина напоследък зимите са станали по-меки и с по-малко сняг (изключвам зимата на 2012 :)), за да провъзгласим пролетта за настъпила ще очакваме съществена разлика със зимата. А ако сме имали наистина мека зима, март няма да донесе съществена промяна.

Второ ако имаме спомени от преди 25-30 години очевидно сме на поне толкова. Едва ли някой би оспорил, че нетърпеливостта на хората за настъпването на пролетта расте с възрастта. Затова, ако някой ви каже че пролетта идва по-късно, той по-скоро има пред вид, че е започнало да му се иска да идва по-рано.

DHL, do you handle with care ?

Наскоро поръчах от http://www.chainreactioncycles.com/ разни благинки за колелото, сред които и ето тази много красива главина. Всичко беше почти наред, само дето главината вместо с 32 дупки е с 24. Тъпото е, че имам прекрасна шина с 32 дупки, но реших че ще я ползвам за предна и продължавайки с упорството си  поръчах отново от chainreactioncycles шина на DT s 24 дупки. Шините с 24 дупки са кът и в БГ не могат да се намерят.

Вече очаквах от DHL да ми доставят шината, когато получих позвъняване от непознат номер. Беше от представител на DHL. Пратката вече е в София, но опаковката е нарушена и може би трябва да се преопакова. Второ позвъняване. Може би артикула е повреден? Желая ли да видя снимки? Дали желая да видя снимки ?

Малко посмачкана шина на DT
Малко посмачкана шина на DT

Мамка му, а изглежда толкова красива.

Хубавата новина е че chainreaction и dhl.co.uk са признали „щетата“ и би трябвало да получа replacement. Но да видим… Ето писмото от chainreaction:

Hi Stefan,
Thanks for your email.
Firstly, I am sorry to hear that you have received a damaged item from us. This is certainly not an issue we have to deal with very often.
I have created a replacement order(Order ID XXXXXXXX) for the damaged item which is being processed and will be dispatched soon.
I hope this sorts the problem for you.
Thanks,
Damian

P.S. Слава богу получих чисто нова шина и то доста бързо. Даже този път е едно цяло парче, а не е сглобяема. 🙂

Never underestimate the importance of local knowledge

Това е мотото на рекламна кампания на голяма международна банка. Накратко, идеята е, че на различни места по света има различни символи и код на поведение за най-различни ситуации. Например:

HSBC flowers

Мотото ми се е набило в главата от списание, в което всеки месец имаше публикувана различна версия на тази реклама. Не си спомням за примери на „local knowledge“ с Япония, но едва ли рекламната агенция не се е възползвала от толкова богата на различия култура. Елементарен пример… цитат от Уикипредиа:

Japan and the V sign in photographs

One account of the V sign’s use in portrait photographs claims that during the 1972 Winter Olympics in Sapporo, Hokkaid? figure skater Janet Lynn stumbled into Japanese pop culture when she fell during a free-skate period—but continued to smile even as she sat on the ice. Though she placed only third in the actual competition, her cheerful diligence and indefatigability resonated with many Japanese viewers, making her an overnight celebrity in Japan. Afterwards, Lynn (a peace activist) was repeatedly seen flashing the V sign in the Japanese media. Though the V sign was known of in Japan prior to Lynn’s use of it there (from the post-WWII Allied occupation of Japan), she is credited by some Japanese for having popularized its use in amateur photographs.[25] According to another theory, the V sign was popularized by the actor and singer Jun Inoue, who showed it in a Konica photo camera commercial in 1972. Japanese may also be associating with their onomatopoeia (gitaigo) for smiling. The number „two“ is „ni“ in Japanese, and the onomatopoeia for smiling generally begins with the sound „ni-„, such as „niko niko“ or „niya niya.“ [26]

Това не е майтап. Всеки, който е бил в Япония го е видял освен това Уики е подплатена със снимков материал:

Victory
Victory

„Never underestimate the importance of local knowledge“… изплува в съзнанието ми в доволно неподходящ момент. Е… Всеки, който е бил в България го е видял.

Posing for a picture...
Posing for a picture...

Downsampling and stair interpolation

These are pixel-greedy days – the more pixels your DSLR has the better. Hardly anyone disputes that. But when it comes to showcasing ones work on the Internet the number of pixels has to be reduced, either to protect copyrighted work, for the sake of reducing file size, or just to be able to display the whole image on screen. Actually thinking about it I display my pictures on screen much more than on paper.

Image resampling is focused primarily on upscaling, e.g. increasing the number of pixels in an image to prepare it for printing, especially when making larger prints. Various resampling algorithms have been devised for blowing up images. Here I make an attempt to compare some of these methods, when reducing the size of the image.

Downsampling inevitably wipes out some of the detail – there are simply less pixels to store the data. Also due to the way interpolation works some degree of softness is introduced to the image when downsampling. Sharpness can be brought back by applying some amount of unsharp masking AFTER the image has been downsampled.

One of the things I’ve payed special attention to when looking at the results from down sampling is if the given method manages to preserve fine detail. For example the detail textures small patterns etc. The move to try different interpolation methods for down sampling was a method called stair interpolation. The basic idea behind this method is to perform the dawnsampling in incremental steps (hence stair interpolation), each step preceded by applying some USM. In theory applying USM before down sampling should fightback some of the softness introduced. Reading through some blogs there was a fair amount of discussion if this works, is useless or even degrades the quality of the resulting image.

Speaking of USM – sharpness is largely a thing of personal taste. Yet for pleasing results, edge halos and aliasing must be avoided.

I also found some references that many interpolation algorithms behave similarly at particular resampling ratios, like 50%, one third etc. This may be so but my tests did not reveal anything outrageous, so resample at whatever steps you want to, I guess.

In the test results I’ve also included crops from the originals so one would be able to judge what to expect from the crops. First example shot with Canon 50mm f 1.4 on tripod, second with Canon 17-40 f4 L on tripod, third and fourth Canon 100mm f2.8 macro hand held. All mounted on a 20D.

The last 3 step stair interpolation is intentionally quite over sharpened to show the perils of pushing USM way too far.

All in all I believe stair interpolation has potential to bring up really fine detail to downsampled images. It is interesting to note that the amount of sharpening needed varies hugely depending on the subject matter. For instance the second example shows some really ugly artifacts even at fair sharpening applied while the third example shows pleasing detail on the girl’s eyelashes at severe amounts of USM. If you are really mad about detail, you could do selective sharpening at each step and bring detail only where you need it. You might also need special medical help 🙂

Happy downsampling !

References

  • controlledvocabulary.com
  • americaswonderlands.com
  • contaxg.com
  • photo.net
  • prophotohome.com

    Landscape/architecture

  • method result
    original
    bell – irfan view 3.99
    BSpline – irfan view 3.99
    Hermite – irfan view 3.99
    Lancoz – irfan view 3.99
    Mitchell – irfan view 3.99
    Triangle – irfan view 3.99
    Bicubic – Photoshop CS2
    Bicubic Sharper – Photoshop CS2
    2 step stair bicubic (USM: 130/0.8/5, 140/0.7/5) – Photoshop CS2
    2 step stair bicubic (USM: 160/1/5, 140/0.7/5) – Photoshop CS2
    3 step stair bicubic (160/1/5, 150/0.8/4, 130/0,6/4) – Photoshop CS2

  • Landscape

  • method result
    original
    bell – irfan view 3.99
    BSpline – irfan view 3.99
    Hermite – irfan view 3.99
    Lancoz – irfan view 3.99
    Mitchell – irfan view 3.99
    Triangle – irfan view 3.99
    Bicubic – Photoshop CS2
    Bicubic Sharper – Photoshop CS2
    2 step stair bicubic (USM: 130/0.8/5, 140/0.7/5) – Photoshop CS2
    2 step stair bicubic (USM: 160/1/5, 140/0.7/5) – Photoshop CS2
    3 step stair bicubic (160/1/5, 150/0.8/4, 130/0,6/4) – Photoshop CS2

  • Portrait

  • method result
    original
    bell – irfan view 3.99
    BSpline – irfan view 3.99
    Hermite – irfan view 3.99
    Lancoz – irfan view 3.99
    Mitchell – irfan view 3.99
    Triangle – irfan view 3.99
    Bicubic – Photoshop CS2
    Bicubic Sharper – Photoshop CS2
    2 step stair bicubic (USM: 130/0.8/5, 140/0.7/5) – Photoshop CS2
    2 step stair bicubic (USM: 160/1/5, 140/0.7/5) – Photoshop CS2
    3 step stair bicubic (160/1/5, 150/0.8/4, 130/0,6/4) – Photoshop CS2

  • Landscape/architecture

  • method result
    original
    bell – irfan view 3.99
    BSpline – irfan view 3.99
    Hermite – irfan view 3.99
    Lancoz – irfan view 3.99
    Mitchell – irfan view 3.99
    Triangle – irfan view 3.99
    Bicubic – Photoshop CS2
    Bicubic Sharper – Photoshop CS2
    2 step stair bicubic (USM: 130/0.8/5, 140/0.7/5) – Photoshop CS2
    2 step stair bicubic (USM: 160/1/5, 140/0.7/5) – Photoshop CS2
    3 step stair bicubic (160/1/5, 150/0.8/4, 130/0,6/4) – Photoshop CS2

    Camera profiles in Adobe Lightroom

    This simple test tries to illustrate the diffrences between the camera profiles avalable in Lightroom 2.2, in particular the profiles for Canon 20D. I was intereseted particulary in the differences that the profiles give to skin tones. To test a picked an image with pleasing skin tones (at least according to me). The image is taken with the magnificent EF 100mm Canon prime macro using available light. The images produced are out of the box – no tinkering done with any of the sliders within the develop module. I guess results can vary vastly from image to image, depending on factors like color balance, camera, etc. Anyhow here is what I got :

    adobe standard
    Adobe standard
    camera faithful
    Camera faithful
    camera landscape
    Camera landscape
    camera neutral
    Camera neutral
    camera portrait
    Camera portrait
    camera standard
    Camera standard


    P.S. This is really very unscientific. Not trying to prove anything here, test is done primarily for fun.

    Canon EF 100-300 f5.6 L

    First the facts from the Canon literature:

    Marketed June 1987
    Original Price 93,800 yen
    Lens Construction (group) 10
    Lens Construction (element) 15
    No. of Diaphragm Blades 8
    Minimum Aperture 32
    Closest Focusing Distance (m) 1.5
    Maximum Magnifcation (x) 0.26
    Filter Diameter (mm) 58
    Maximum Diameter x Length (mm) 75 x 166.6
    Weight (g) 695

    High-performance 3x telephoto zoom lens. Synthetic fluorite in group 1 and UD glass in group 2 achieve low refraction and low dispersion. They also effectively correct chromatic and other aberrations. Resolution is high throughout all focal lengths. Images are sharp and crisp. At the 300mm focal length, 0.25x magnification is possible.

    I did not know this lens existed when I got a chance to shoot a bit with it. Of course I was immediately attracted to the L designation. Zooming is done like the EF 100-400L monster, but here there are no lock rings. This means the lens creeps at the slightest tilting. This lens has a new definition of slow focusing for me… it takes ages to focus. The noise produced when focusing reminds me that of a plane retracting its landing gear.

    The test is made in a real world situation. The realworldness comes from the fact that the shots were taken raw and then processed to tiff with DPP 2.0.3.7 with its default params, meaning some sharpening has been applied, but anyway that’s most people’s workflow. All shots were taken with a 20D, mounted on a sturdy Manfrotto tripod using cable release and mirror lockup. Here is a quick set of tests and comparisons against the cheapo EF 100-300 f4.5-5.6.

    I won’t comment on the results presented here. It’s up to you to interpret the images.

    I apologize for my stupidity of not taking shots of the same part of the building with the two lenses.

    Center performance at 100mm

    F number 100-300 f5.6 L 100-300 f4.5-5.6
    f 5.6
    f 8
    f 16

    Corner performance at 100mm

    F number 100-300 f5.6 L 100-300 f4.5-5.6
    f 5.6
    f 8
    f 16

    Center performance at 300mm

    F number 100-300 f5.6 L 100-300 f4.5-5.6
    f 5.6
    f 8
    f 11
    f 16

    Corner performance at 300mm

    F number 100-300 f5.6 L 100-300 f4.5-5.6
    f 5.6
    f 8
    f 11
    f 16

    Temperatures in my city in my lifetime

    People usually have subjective perceptions for quantities and values. Yet somehow I felt that despite all that global warming talk skewing my judgment, I cannot be completely mistaken.I remember longer winters with more snow and colder days. I remember clear-cut seasons, with definite spring and autumn. Could all this be just a creation of my imagination, especially when taking into account the childhood memories involved ?

    I resorted to making a humble test of my memory. I obtained the day by day max temperatures (in Fahrenheit) for my city since I was born (1979) from NOAA. This is a matrix of numbers 27×365 – dull and uninspiring. Then I used Graphis to breathe life into the data.

    If you know what you are looking for you can probably see the trend. Going into the new millennium summers seem to be generally warmer. The average temperature also seems to have gone up.

    P.S. This is really very unscientific. Not trying to prove anything here, the plot was done primarily for fun.
    P.P.S. Will make a better plot some day, time permitting.

    Bulgaria is a…

    Ако мислите, че Давид Черни се занимава единствено с изкуство, дълбоко се лъжете. Приносът му към подобряването на качеството на интернет търсачката google е не по-малък. Просто идете на google.com и напишете следната фраза: „Bulgaria is a“. Google suggest дава най-точния отговор.

    Bulgaria is a