Kinovastaavuus ja aukko

Nykyään yleistyvät pienikokoiset peilittömät järkkärit, joissa kenno on pienempi kuin niin kutsutuissa täyden koon (kinokoko) kameroissa. Näitä kameroita sanotaan yleisesti kroppikennoisiksi. Kinokokoisen kennon ja kroppikennon kokoero ilmaistaan kroppikertoimella (suuremman kennon diakonaalimitta jaettuna pienemmän vastaavalla). Kroppikennoisia kameroita varten tehdyistä objektiiveista puhuttaessa mainitaan usein polttovälin kinovastaavuus. Esimerkiksi 50 mm objektiivin kinovastaavuus kroppikertoimella 2 on 100 mm, kuvan rajaus on siis sama kuin 100 mm kino-objektiivin rajaus kinokoon kamerassa. En muista koskaan kuitenkaan nähneeni polttovälivertailun yhteydessä mainintaa toisesta seikasta eli aukon kinovastaavuudesta, joka on samalla tavalla riippuvainen kroppikertoimesta. Kertoimella 2 vastaavasti aukko f4 vastaisi aukkoa f8. Usein näkee kuitenkin esimerkiksi mainonnassa liitetyn harhaanjohtavasti samaan yhteyteen objektiivin kinovastaava polttoväli ja sen todellista suurinta aukkoa kuvaava luku. Väkisinkin tulee mieleen, että on tarkoitus saada asiat näyttämään kauniimmilta, kuin ne oikeasti ovat. Toisaalta onhan kinovastaavan polttovälin ilmoittamisesta hyötyä, jos kuvaaja on tottunut ajattelemaan ”kinokoossa”, mutta myös aukko tulisi silloin ilmoittaa kinovastaavana. Näin siitä olisi ehkä hyötyä myös syväterävyyden mieltämisessä, eikä ainakaan syntyisi vääriä mielikuvia.

Itse olin muodostanut mielikuvan polttovälin, aukon, valotusajan ja filmin herkkyyden välisestä vuorovaikutuksesta jo viime vuosisadalla kinofilmijärkkärillä kuvatessani. Siirryttyäni käyttämään Micro Four Thirds -kameraa, jonka kroppikerroin on 2, alkuun välillä vähässä valossa kuvatessani ihmetelin, kun valotusaika ei ollutkaan niin pieni, kuin olin sen kuvitellut valitsemallani ISO, aukko ja polttoväliyhdistelmällä olevan. Se johtui yksinkertaisesti siitä, että olin ajatellut polttovälin kinovastaavana ja katsonut aukon kameran etsimestä. Olen siis kuvitellut kuvaavani esimerkiksi 100 mm vastaavalla objektiivilla aukolla 4, kun minun olisi tullut kuvitella kuvaavani 100 mm vastaavalla objektiivilla aukolla 8. Silloin en enää olisi ihmetellyt pitkää valotusaikaa. Kuvaaja, jolla ei ole tällaisia päähän pinttyneitä mielikuvia, kuvaa 50 mm:n objektiivilla aukolla 4 sen kummemmin ihmettelemättä.

About exposing to the right (ETTR) with Sony DSC R1 and Olympus OM-D

There has been discussion about the usefulness of exposing to the right (ETTR) in the internet. I made some tests in order to see myself what it’s all about. The results were so interesting that I decided to tell about them to others too.

 The principal of this method is to expose the photo as light as possible without overexposing the lightest areas where you want to show tones. When you expose like this you get more details and less noise to your photos than if the exposure is based on the meter readings in camera. This method is useful with RAW files only.

 The problem with ETTR is how to indicate in the viewfinder the over exposure and the areas where it’s going to happen before the photo is taken. In cameras with optical viewfinder it isn’t possible. Some cameras with electronic viewfinders can show a real time histogram. The histogram is usually very small and hard to read and it can‘t show the areas which are going to be overexposed. Olympus has developed a method in which the areas of over and under exposure are shown in red and blue colors in the viewfinder.

But nothing is free. ETTR is made by increasing exposure time with (+/-) –control. It can easily be 1 – 2 EV. You must pay attention to exposure time which can be double or triple.

The effect of ETTR is bigger on higher ISO settings.


I haven’t tried to make scientifically exact results in these tests and I couldn’t have reached them even if I have tried. My only meaning was to make these tests so that I could reliably see the effect of ETTR with my test cameras and different ISO values.

All picture settings in both cameras are set to minimum. They shouldn’t have effect in RAW images, but to be sure. In Lightroom I made exposure, sharpening, noise reduction and white balance adjustments so that the pair of photos taken at the same ISO values had same settings.


Target for test photos.

The target was a part of our bookshelf. The white rectangle in the photo is the 600 x 400 pixels area in the detail pictures. The resolutions of the test cameras are not the same. That’s why the area in the 1:1 detail images is not quite similar.

I took with both test cameras a pair of photos using different ISO values. I exposed the first photo without any corrections to exposure time (+/-) 0. The second photo I took using ETTR.   

Sony Cyber-shot DSC R1

R1 is Sony’s 10 megapixels fixed lens digital camera which looks a lot like a DSLR. It was released in 2005. It has been my very good and reliable companion for nearly seven years.

It’s possible to see a real time histogram in the electronic viewfinder of Sony R1, but it’s just as impossible to use as I earlier told. Even +2 EV (+/-) adjustment doesn’t over expose anything but the shining highlights in the test photo. However histogram shows high over exposure. I think the histogram is calibrated for jpg-images and it’s useless with raw-images.

Viewfinder image of Sony R1


Normal exposure (+/-) 0                                                    Exposure correction (+/-) +2

R1, ISO 160


R1, ISO 160, (+/-) 0.


R1, ISO 160, (+/-) +2.

R1, ISO 400


R1, ISO 400, (+/-) 0.


R1, ISO 400, (+/-) +2.

R1, ISO 1600


R1, ISO 1600, (+/-) 0.


R1, ISO 1600, (+/-) +2.

R1, ISO 3200 (max. ISO)


R1, ISO 3200, (+/-) 0.


R1, ISO 3200, (+/-) +2.


Whole image ISO 3200. Click the image to see larger version (width 1000 pixels).

R1, ISO 3200, (+/-) 0.

R1, ISO 3200, (+/-) 0.

R1, ISO 3200, (+/-) +2

R1, ISO 3200, (+/-) +2

Olympus OM-D EM-5

OM-D is a Micro Four Thirds camera with 16 megapixels CMOS sensor. It was released in April 2012. I used 12–50mm 1:3,5-6,3 EZ lens in these tests.

Viewfinder image of Olympus OM-D


1.                                                                                             2.

In the first (1.) viewfinder image (+/-) correction is +1,7 EV and there are no over exposure warnings in the image. In the second (2.) viewfinder image (+/-) correction is+2,0 EV and the red warning color shows the areas which are going to be over exposed.

OM-D, ISO 200


OM-D, ISO 200 (+/-) 0.


OM-D, ISO 200 (+/-) +1,7.

OM-D, ISO 400


OM-D, ISO 400, (+/-) 0.


OM-D, ISO 400, (+/-) +1,7.

OM-D, ISO 800


OM-D, ISO 800, (+/-) 0.


OM-D, ISO 800, (+/-) +1,7.

OM-D, ISO 1600


OM-D, ISO 1600, (+/-) 0.


OM-D, ISO 1600, (+/-) +1,7.

OM-D, ISO 3200


OM-D, ISO 3200, (+/-) 0.


OM-D, ISO 3200, (+/-) +1,7.

OM-D, ISO 6400


OM-D, ISO 6400, (+/-) 0.


OM-D, ISO 6400, (+/-) +1,7.

OM-D, ISO 12800


OM-D, ISO 12800, (+/-) 0.


OM-D, ISO 12800, (+/-) +1,7

OM-D, ISO 25600 (max. ISO)


ISO 25600, (+/-) 0.


OM-D, ISO 25600, (+/-) +1,7.


Whole image ISO 25600. Click the image to see larger version (width 1000 pixels).


OM-D, ISO 25600, (+/-) 0.


OM-D, ISO 25600, (+/-) +1,7.

The picture quality in both cameras at the highest ISO setting seems to be usable at least in small size, for instance in the internet or as 10 x 15 cm prints. These tests were so convincing that I have no doubt about the usefulness of ETTR.

– MH



Photorealism is a trend of art which was born in the 1960’s in U.S.A. It was like an opposite of the abstract painting. In photorealism photograph is the starting point to a painting. The artist copies the photo as precisely as possible. The trend came to Europe in the early 1970’s.

In 1974, Ateneum the major museum of art in Finland arranged an ARS 74 exhibition. The motive of the exhibition was photo-realism and most of the paintings were based more or less accurately on a photograph. The only motive the artists had was surely not only to show their technical skills, there was also a political and social message in the paintings. I, however, was impressed by the admirable ability of many artists to create a painting which was just like its basis, the photograph. I wanted to try to do something like that too.

Back to the nature

Back to the nature, painting

The painting, Back to the nature, 1975 – 1976. I have tried to find the original paper photo and negative for comparison, but couldn’t find them.

So I chose as basis of my painting a photo that I had taken with my first 35 mm SLR camera. From the original 10 x 15 cm color photo I enlarged a black and white copy and made a grid over it. Using the corresponding but larger grid on cardboard I made the “Back to the Nature” painting with an airbrush and black Indian ink. Maybe there is some deeper message hidden in my painting too.

Another painting “Gate” which is based on my photo is a view from Uusikaupunki, a town in western Finland.


The photo

The original slide is missing at the moment but I have a scanned version which I have changed a bit in Photoshop. I had to close an open door which was in front of the gate and didn’t look good. A print from this version was the basis of this painting.

Gate 2002, the painting

The painting, Gate 2002, egg tempera.

The painting is made with egg tempera.