Nikon lens hood acronyms

Here is what they mean folks:

Code Type Notes
HB Bayonet hood The most common one today. Usually has a flower-petal design.
HE Extension for already existing hood on long lenses Not very common
HK Slips on the lens, locks with a knob. Older lenses seems to have this sometimes for long telephoto lenses
HN Screw mount hood Never seen this one myself.
HR Rubber hood Great for prime lenses especially if you need to shoot through a glass pane. Keeps the reflexes out so the glass is hardly not visible.
HS Snaps on Like a lens cap. Never seen this one myself.

Tutorial: Orton Effect using GIMP

The orton effect is a very special effect created by photographer Michael Orton where he created what is called the Orton Slide Sandwich. He used photographic slides to overlay a photograph with an out-of-focus shot of the same scene. This created a very special effect that was named after him.

Today when the darkroom is a lightroom created by electrons and photons stored in a computer core memory instead the Orton effect can easily be simulated by using software. This tutorial will show you how to create the Orton effect using a single picture. You can of course still shoot an out-of-focus picture just in the original version of the Orton Slide Sandwich but there is no real need for it since software today can create lens blurr that you can have even more control over.

This tutorial is based on GIMP version 2.6 and I used it in MS Windows XP service pack 3.

Photographs suiteable for this effect are macros of flowers, landscapes and so on. You should select a photograph that have contrasts and rich tones, they seem to work best with the Orton effect.

  1. Open the photograph in GIMP and go to the layers window pane where you will find one layer called ”Background” presently. This is the picture you have chose.
  2. Start by lighten the picture about 1 EV (one f-stop) this can be done from the menu by selecting brightness and contrast and then moving the brightness slider upp substantially. Exactly how much you need to experiment.
  3. Duplicate the background layer by right clicking on it and select duplicate.
  4. Select the new layer and change the mode to multiply. You will now see a picture with a rather harsh contrast. If it is too harsh you need to go back to step 2 and lighten the starting picture even more.
  5. Select the top layer, your background copy because the next step is only applied to this layer.
  6. Find in the menu Filter -> Blur -> Gaussian Blur
  7. Adjust the filter setting to something around 30 points works well for me. This depends a bit on how large your photograph is. Experiment. If your first attemt is not okay use the undo function and apply a different value and try again.
  8. When you are satisfied, flatten the layers from the layers menu.
  9. Adjust levelscurves and saturation to your liking.
  10. Save the photograph under a new name.

That was not too difficult was it? Here below is a step by step how the picture will look after each step in the tutorial above.

After step 1 has been applied

After step 2 was applied

After step 3
After step 3
After step 6 the picture looks like this.
After step 6 the picture looks like this.
When finished adjusting the final picture looks like this
When finished adjusting the final picture looks like this

I should add that the orton effect created here is a bit exaggerated with more blurring than necessary just to show the principle. In reality you would probably want to apply a little less blur than what I used here. But it is of course all up to you :)

Anders Pettersson


Photo Challenge: The Orton Effect

From Wikipedia:

Orton imagery, also called an Orton slide sandwich, is a photography technique which blends two completely different photos of the same scene, resulting in a distinctive mix of high and low detail areas within the same photo.[1] It was originated by photographer Michael Orton.

It is time to get creative with Photoshop, or perhaps just using your cameras double exposure feature if you have it (the D300 does). Working with Photoshop or GIMP has the added benefit that you can take any photo, apply lens blurr and work on it even if you never did an out of focus exposure when you took it…

These are the steps in creating an Orton Effect:

  1. Select a nice scene and take a photograph that is +1 EV over-exposed.
  2. Defocus so that the scene is out of focus by switching to manual focus and blurring the picture slightly. This should also be +1 EV over-exposed.
  3. When you are home in photoshop or the photo editing software of your choice add the two images together in two different layers. Change the blending from ”Normal” to ”Multiply”.
  4. (Play around)

Of course you can stard with any photo you already have and make two lightened copies of it and then blurr one of them and blend them together. This is also acceptable.

Here are examples of the orton effect on Flickr.

Below are links to other sites that explains how to attain this effect both with film and digital cameras:

Good luck!

(Post your contributions in the comments section with links to your photographs)

Att lagra bilder för framtiden

Ända sedan den första riktiga kameran såg dagens ljus 1826 så har man lagrat bilder på olika medium även om slutprodukten – en pappersbild – ofta är väldigt lika i dag som den såg ut över 200 år sedan så är negativen väldigt annorlunda. Från början använde man silverbelagda glasplåtar, sedan övergick man mer mot fotokänslig emulsion, i mer modern tid använde man kamerafilm av cellulosa med en ljuskänslig silveremulsion och nu för tiden fotograferar de flesta digitalt även om film fortfarande förekommer så vinner digitalfotot hela tiden mark.

Under hela tiden har man haft problem med att lagra negativ på ett säkert sätt. Emulsionen och silverbeläggningen trots framkallning och fixering åldras och det blir svårare och svårare att framställa kopior från originalen. Men trots detta kan man 200 år efter de första fotografierna fortfarande, om än med viss svårighet, använda negativen.

Om vi skall omsätta detta i digitala termer blir problemet uppenbart. Handen på hjärtat hur många datorer som säljs idag har ens diskettstation? Hur många har kvar 5 1/4″ (fem och en kvarts tum) disketter? Har ni ens sett en 8″ (åtta tums) diskett användas? Var hittar man en sådan gammal diskettläsare? Och nu pratar vi inte 200 år tillbaka i tiden, vi pratar knappt 20 år. 

Inte nog med att digitala media går väldigt snabbt framåt och åldras mycket snabbt, arkivbeständiga media är det väldigt snålt med. Jag pratade med en arkivarie en gång som berättade att till de digitala media som räknades som arkivbeständiga med en livslängd på 150 år eller mer räknade man i princip bara hålremsa och hålkort som måste tillverkas med speciellt syrafritt papper, s.k. arkivpapper. På disketter lagrar man informationen med svaga magnetiska signaler som faktiskt med tiden klingar av så sakta och blir allt svårare att läsa tills informationen i princip inte länge kan skönjas. Tidsperspektivet här är kanske något tjugotal år. Magnetband lider av en liknande problematik och vem kan ens få tag i en trådspelare för att spela upp magnetisk tråd som föregick rullbandspelarna som gjorde brett intåg på femtiotalet?

Hårddiskar har samma problem som disketter, de måste underhållas ofta för att man skall kunna känna sig säker på att informationen fortlever och finns kvar. I princip måste man räkna med att en hårddisk är kasserbar efter ca fem år. Dels för att gränssnitten förändras men även för att datat på den sakta klingar av och drabbas av felaktigheter. Det går inte att lägga undan en hårddisk i ens tio år och förvänta sig att man kan använda den efter detta.

CD och DVD lagrar informationen optiskt, med en laser så skjuter man små hål i ett informationsbärande aluminiumskikt i skivan. Detta skikt ligger precis under ytan på ovansidan av skivan, minsta repa här kan göra den helt oandvändbar. Ovanpå aluminumskiktet finns olika lackskikt och skyddsplast och andra lager och en speciell typ av lim används för att foga samman lagren både i de skivor man bränner själv och de skivor som pressas i fabrik för kommersiella produkter från en glasmaster.

Ingen av dessa har en särskilt lång beständighet, jag har själv CD-skivor som har börjat bli förstörda av ålderns tand utan att de för den skull blivit repiga eller liknande. En del är skivor jag i princip aldrig lyssnar på de ligger mest i en kartong. Skivor man bränner själv har knappast mer än 3-5 års livslängd även om de aldrig spelas. Förvaras de mörkt och i rätt luftfuktighet kanske de kan hålla några år längre men glöm 200 år. Dessutom utvecklas tekniken hela tiden. Just nu är den bakåtkompatibel, en gammal CD kan spelas i en modern DVD-läsare i en dator för det mesta men inget säger att detta måste fortsätta ens tio år till.

Vad har vi kvar för olika medier egentligen att fundera över? Gamla minnestyper som ferritminnen och trummor och liknande kan vi slå ur hågen för de har dels alldeles för liten lagringskapacitet och finns inte att få tag i kommersiellt längre. Hålremsa och -kort är dött, det går knappt uppbringa en sådan läsare eller stans för pengar och även om det gick så är kapaciteten väldigt låg, en enda bild från en modern kamera skulle medföra buntvis med hålkort eller rejäla rullar hålremsa så vi kan utesluta dessa helt, trots arkivbeständigheten.

Det egentligen enda vettiga lagringsmediet idag är nog hårddisken och jag tänker särskilt på den löstagbara USB eller FireWire-anslutna hårddisken som har egen strömförsörjning och kan flyttas lätt. USB och Fire-wire som interface har funnits några år nu och kommer nog inte försvinna i brådrasket. Så även om själva hårddiskarnas gränssnitt har vandrat från IDE och SCSI till SATA och liknande så är fortfarande datagränssnittet USB eller Fire-wire detsamma nu som för fem år sedan. När tekniken så tar ett nytt trappsteg måste datat flyttas till det nya interfacet och det är just detta som är grejen, datat måste underhållas för att format och media skall kunna läsas även i framtiden.

Det går inte att bara låsa in mediat och tro man kan använda det om 20 år, det måste hela tiden transporteras till nya media och följa utvecklingen.

Till sist ett tips: Många hårddiskar kan själv fixa sektorer som börjar bli dåliga. Men för att de skall upptäckas måste ibland hela disken läsas igenom. Detta är en av orsakerna till att det är så bra att ta fullständiga backuper minst en gång i månaden. På de viset hinner systemet upptäcka dåliga sektorer innan de är så dåliga att data tappas. På moderna diskar finns ett antal extrasektorer som ”mappas in” där det behövs. Det förlänger livslängden på disken och ökar dataintegriteten.

The Faroes

Faroese Panorama
Panorama of the Faroe Islands in all it's surreal beauty.

It was in May 2006 when I got on the aircraft taking me to Copenhagen and the further on with the local carrier to the Faroe islands. This group of islands are scattered about in the north atlantic. If you draw a line from the northernmost point of Scotland straight to Iceland you will find the Faroes in the middle of this line roughly. Or you may explore them on this map here.

The name is Old Norse and means ”sheep islands” which is a very descriptive name. The language is a branch of Old Norse, grammatically close to Icelandic but when spoken reminds very much of some western dialects of Norwegian. I saw Faroese and Icelandic people speak with eachother and did not have much trouble understanding each other. I had quite some problems understanding spoken Faroese but written was easier and some words, though no longer in use in Swedish, were very similar to the dialect spoken in the part of Sweden where my father grew up which I learned to speak when I was 9.

Land & Sea
Fyords and Mountains...

Even though the Faroes are now Danish and Denmark is part of the European Union the Faroes is actually not, when Denmark entered the Faroese declined and remained outside the union. In this matter they are independent and people I spoke with said jokingly that this was due to the fishing restrictions put on by the European government wich would spell disaster for the Faroese people who has it as their main income source. Apart from fishing there are sheep farming and that is about it. Most other people work with supporting the fishing industry one way or another and there are very limited other natural resources on the islands that could sustain their economy.

In the whole Faro islands there are less than 50 000 inhabitants. All villages and the city of Tórshavn is located along the coast lines. The islands are quite mountainous and inhospitable and the wind is a constant reminder of the harsh climate. However, because of the sea the temperature is very moderate both in the summer with cool breezes and rain and in the winter the temperature drops but never hits the really cold temperatures that we sometimes suffer here in Scandinavia. On the average winter temperatures are around 5°C and in the summer they lie around 10°C so you see people wearing the traditional wool sweaters not unlike those of fishermen in the north of Norway or Russia all year around.

The Giants
The Giants, rocks out of the coast of the Faroes

The weather is constantly changing it is like it goes through phases and likes to throw tantrums. One day we were driving back from the job and the car was suddenly hit by a wind gush from the side and with it came driving rain. It rained so hard that the road was difficult to see even though it was broad day light. The next day in the paper we saw that a lorry had blown off the road in the place where we passed. As we drove the other way we saw the people trying to salvage the lorry, it had fallen off the road onto a spread of land just below. The driver was apparently a little shook up but otherwise unharmed. He was lucky though, had he gone through the fence in any other place he would have ended up falling 30-50 meters straight into the cold water of the north Atlantic. This is a serious hazard that actually kills a number of people every year in the islands.

DSC_2411
The very interesting landscape on the islands

 

They had the same saying here as they had in the north of Norway in Narvik when I was there, ”if you do not like the weather, just wait five minutes”. And it was true of course, we had during one days rain, cloudy, sunny, calm, very windy and then a rain storm and in the evening we had nice and calm weather again. Very interesting.

Hiking the hills of the islands is quite popular both with the locals and as tourists. Though the winds may pose a hazard there are not very many other hazards you could encounter and it is a great opportunity to take some brilliant landscape photographs. However you should be aware that a reasonable physique is required to climb the Faroese hills, they can be steep and challenging. The old people there has a special walk where they keep their hands on their back and never walk directly in the direction of the incline, instead they walk in S shaped curves slowly scaling the hills and once up they love to have a coffee.

The Resting Place
Gjógv, a natural harbour

A lot of people keep sheep and apart from fish sheep meat is the main source of protein in the Faroese diet. Whale meat and blubber is also traditional but not as common any more perhaps of the restrictions of whaling (or just because the taste is a bit… difficult unless you have grown up to like it).

The flight was great, when we were about to land we flew in through this canyon-like gorge between two of the islands and then landing on Vágar airport, the only international airport in the Faroes. From there I got picked up by car and we drove to Tórshavn, the capitol city in the Faroes. Tórshavn literally means ”the harbour of Thor” and it is the main city of the Faroe islands. The Vágar airport is located on a different island and was built by the British troops during the later part of the WW2 when they occupied the Faroe Islands in an attempt to establish dominance in the north Atlantic sea.

The landscape is very different from the forests that I was used to. There are virtually no trees, the few I saw was planted in gardens in Torshavn and in the countryside there are grass, moss, lichen and shrubbery mainly. Perhaps a few other plants and flowers and the rest is taken care of by the grasing sheep. It is a common sight to see people break for sheep on the roads. The sheep don’t seem to mind the cars much at all they just wait for them to go past.

In the last years the focus on infrastructure has been high and several tunnels between the main islands has opened. There are two mobile telephone operators on the Faroe islands, FT (Faroe Telecom) and Kall (pronounced roughly ’kathlh’, the double-l sounds is very distinctive in Faroese).

Here are some more pictures from my trip.

Vidareidi Church
The Vidareidi church on the Faroe Islands.

Warm Light / Cold Light

Do you answer yest to one or more of these questions?
  • Do your indoor photographs come out red or yellow?
  • Do your winter photograph seems very blue?
  • Do you get weird colours in people’s faces when you shoot portraits in fluorescent light?

You need to learn more about white balance!

When you take photographs the camera records what it sees. This is a difference to our eyes where the eyes themselves and the brain actually processes what we see before we experience it. Light comes in many different aspects. It can be coloured light or it may be even distributed ”white light” across the spectrum. However the distribution across the spectrum can be uneven and the light is then said to have a certain ”color temperature”.

This temperature is measured in a scale called Kelvin, the same that physiscists use to talk about temperature. And when we speak about light temperature we are speaking about something that the phycisists call ”black body radiation”. The explanation for this phenomenon is somewhat complex and out of the scope here so let’s just say that when you heat something up enough it starts to emit light.

If you think about a piece of iron when it is heated enough the light from it is white almost with a blue streak. And when it cools off it becomes first yellow, then orange, then red and after that you can not see the color any more. So physicists talk about various colours as they are related to objects and what colour the radiate at different temperatures. Now we can relate temperature with colour.

Kelvin is not so different from degrees Celsius. There is however an offset of 273,15 (273 will do for us) degrees between the Kelvin scale and degrees Celsius. That is because Celsius has it’s zero point when water freezes (at sea level) and Kelvin has it’s zero point when there is a total absence of energy, the coldest there can be. This point is -273,15 °C so therefore room temperature is close to 300 K. Now, to see something glowing it is generally around 2000 K or more. Light from the sun at mid day can be estimated to have a light temperature of about 5 600 K.

In the evening and in the morning the tones go more pronounced red and yellow, the golden hours as they are called in photography takes place roughly one our after sunrise and one hour after sunset and they are great for nature photography. Light from a light bult is usually somewhere around 3 200 K giving a much more red-yellow light than the sun.

Indoor where we use electrical light the light radiated from these are much colder compared to the sun. Our brains adjust to this automatically but not our cameras necessarily. There is a control on the camera called White Balance. This control tells the camera what the temperature should be of the main light source in the picture and the camera will adjust the red-blue balance of the picture accordingly.

Today most cameras have automatic detection of white balance but this can sometimes be wildly wrong so it is always a good thing to try to learn to set this yourself. Most cameras today have several settings for white balance, here are some that are common on most cameras:

  • Automatic mode
  • Sunny
  • Shadow
  • Bulb light
  • Fluorescent light
  • Flash light

If you are photographing in RAW format you don’t need to worry about these, because you can always set them in your post processing of the pictures. But if you are shooting in JPEG format you should take care and try to get the white balance right from the beginning. If you fail to do this you may compensate a little bit in your post processing software (Google Picasa, Adobe Lightroom, Photoshop, GIMP or the tool of your choice) but when you do that to a compressed picture such as a JPEG there will be artefacts introduced. Slight adjustments are okay but if you need to change it more than a few hundred Kelvin then you will notice you start getting strange things in your picture.

One example is the sudden appearance of bright blue pixels in dark or black areas. It does not look good.

At the same time there really is no need to fully compensate for white balance, sometimes the blueish or reddish tone can actually make the picture a very nice picture but if you are tired of having every picture you shoot indoor come out as yellow-orange then you need to find and adjust your cameras white balance setting.

It should be fairly obvious which setting goes where, after all the names says it all. At this point I want you to look up your camera’s manual and find the chapter on white balance. Take a few test shots with different settings and learn the difference between them.

Sun and Ice
Snow and Ice. Example of the colour of light at sunset.
Micro Ice Forest
Micro Ice ForestExample of mid day colour of light.

NSA has released Cryptol

 Cryptol is a language used to specify, implement, test and verify cryptographical algorithms. I have just taken a first glance at it and it seems really competent. All cryptography buffs out there should rejoice over this tool.

Cryptol can further ”compile” your cryptographic algorithms into languages such as VHDL, C and Haskell. You may download a trial version for non-commercial uses from the galois site.

Blackbird

The blackbird is a common woodland bird here in Sweden and I have seen several families of them on my way down to lake Mälaren. They have however been difficult to get a picture of, I have had the wrong lens mounted, they are quick little fellas but today I could squeeze off a few shots and I got this one. Not perfect but still shows the little bugger quite well.

Blackbird / Koltrast
Nikon D300 using Nikkor AF-S VR 70-300G ED-IF. Postprocess in Adobe Lightroom, contrast, saturarion, cropping and size reduction.