Has the term focal length become obsolete?

Bild der weißen Olympus PEN E-P7

In analogue times, the world was still simple. If you disregard medium format cameras, which were only affordable for professional photographers these days, there were only 35mm format cameras available. All focal lengths were easy comparable. Nowadays, however, there are several formats available. Besides the 35mm format APS-C and Micro Four Thirds are available, which are showing a different angle of view with the same focal length due to different sensor sizes. To make matters worse, the APS-C cameras also have slightly different sizes. With Canon, APS-C is 22.3 × 14.9 mm2 and 23.5 × 15.6mm2, which sounds little but makes a difference in the recorded angle of view.

Since customers were used to the focal length specifications in 35mm format in analogue times, at the beginning of the digital age camera manufacturers converted the focal lengths of other sensor formats to 35mm using the so-called crop factor. This helped the user to understand which angle of view he could record with the lens. The approach certainly made sense at the beginning because the entire target group of manufacturers were used to the focal length information from the analogue cameras and it was, therefore, easier to sell new products. Nowadays this is no longer the case, as the younger generation did not grow up with the 35mm format. So I notice again and again that I look into questioning eyes when I talk about crop factor and try to explain that the lens with a focal length of 25mm in Micro Four Thirds format records the same angle of view (section) as a 50mm lens in 35mm. After all, the lens says, mostly very prominently, 25mm and not 50mm.

Why don’t we use the angle of view?

In the specifications of the lenses, the manufacturers always specify the angle of view, which is identical to 47 ° for a 25mm in Micro Four Thirds format and for a 50mm in 35mm format. In case the manufacturers would write the angle of view on the lenses instead of the focal length, a comparison would again be possible without any conversion. Even newcomers would understand that the two lenses can be used for the same purpose. For the experts among us, this might be hard in the beginning. Who has the angle of view for each lens in mind, but that is only a matter of time, especially if the corresponding angle of view instead of the focal length is printed on each lens, it would soon be easy for us to have the angle of view ready.

Conclusion

I am aware that this is only a theoretical game of thought. Current practice is too deeply rooted for that. Manufacturers who use 35mm image sensors, in particular, have a strong interest in having this sensor size as a reference. This strengthens their position as the holy grail of image quality. Thought by the end-user, however, it makes perfect sense to use the angle of view, because all lenses would be directly comparable. A conversion of focal lengths would not be necessary. Yes, maybe not for those of you who are well versed, but for those of you who are new to photography and have no idea about all of this, it will be easier.

Your opinion is asked

I am looking forward to discussing the topic with you. So leave a comment with your perspective or opinion. I look forward to a factual discussion with you.

Almbach Gorge the natural territory for the E-M1 Mark III and the 8-25mm lens?

Bild der Kugelmühle der Almbachtalklamm

In my article “My experience with the M.Zuiko Digital ED 8-25mm F4.0 PRO” I showed you already the 8-25mm lens and how flexible you can utilise it. In my holidays I have been in the Alps and visited the Almbachklamm nearby Berchtesgaden. I planned to use the E-M1 Mark III only with one lens and as the Almbach Gorge (Almbackklamm) is very narrow I decided to go with the 8-25mm F4 lens.

Bild der Kugelmühle der Almbachtalklamm

The Almbach Gorge

The Gorge is not far away from Berchtesgaden and close to the B305 in the direction of Salzburg. It belongs to the little village Marktschellenberg. At the entrance is the last working pebble mill, which is still producing marble balls with water power (title image). The gorge is 3km long and ends with the Theresienklause, a dam which was utilised to transport wood through it. The way back is again through the gorge or via the Etterberg and the church of pilgrimage “Maria Heimsuchung”. We left the gorge at half of the way and went directly to the Ettenberg. In case you would like to know more about the route you will find it here.

The gorge, the natural territory for the E-M1 Mark III and the M.Zuiko Digital ED 8-25mm F4 PRO lens

As already mentioned earlier the combination of E-M1 Mark III and the 8-25mm lens is the perfect combination for such a trip. Half of the gorge is at least up to the half very narrow a wide-angle lens is needed, in addition, there are a lot of motifs, which are a bit farer away so that the zoom area of the lens will be completely used. Already at the start, there is a small ravine, which you can reach via a little bridge and therefore a nice easy motif.

8mm F11, 1,6 sec
22mm F11, 1,6 sec

The images already show how useful the zoom range of the lens is and how it can be utilised to create your image, but also why the E-M1 Mark III is the fitting camera for such a hike. With the built-in LiveND filter you can make, without a physical ND filter, long time exposures, which enables you to show the floating water in your images. Thanks to the image stabilisation you can realise these images without a tripod. You. can leave it at home and save weight.

25mm, F13, 2 sec

Many claims that zoom lenses are only used in their extreme focal lengths. In this case 8mm or 25mm. However, this hike showed something else. I also used the focal lengths between the extremes, depending on how the composition of the picture required it. The picture of the church, for example, was made with 18mm. The picture of the watercourse was taken with 14mm.

Conclusion

As already indicated in the headline, the decision to take the M.Zuiko Digital ED 8-25mm F4 PRO with me on the hike was, in retrospect, exactly the right one. The lens covered exactly what was needed with the focal length range. But the E-M1 Mark III was also able to show its strengths to the full. In particular, the image stabilization in combination with the built-in LiveND filters (this is a digital ND filter) was very helpful in realizing images that would normally only have been possible with a tripod and physical filters. So I only had one camera with one lens with me. I could leave the tripod and ND filter at home and thus save a lot of weight, which would otherwise have burdened me on the hike.

Olympus PEN E-P7 and OM-D E-M10 Mark IV compatible with Profoto Air Remote O-TTL?

Silberne Olympus PEN E-P7 liegend

The Swedish flash manufacturer is one of the world-famous. Their studio flash systems are high-quality, very reliable and could be triggered remotely. With Air Remote TTL they have a remote control that can control the light amount via TTL. This makes the studio flash photography much easier than before and speeds up the workflow in the studio. In addition, it is easier to operate studio flash systems.

Official compatible Olympus products

On the Profoto website following Olympus cameras are compatible:

  • OM-D E-M1X
  • OM-D E-M1 Mark III
  • OM-D E-M1 Mark II
  • OM-D E-M1
  • OM-D E-M5 Mark III
  • OM-D E-M5 Mark II
  • PEN-F

On the list are only high-grade cameras, which have as target group professional photographers in mind. Makes sense as those cameras are bought by poeple, who are very interested in photography and therefore most properly are using them also in the studio.

What about the PEN E-P7 and the OM-D E-M10 Mark IV

Recently Olympus released its own system to remote control their system flashes, which controls the flash intensity via TTL. The PEN E-P7 and OM-D E-M10 Mark IV are the first entry-level cameras that support this system. The basic requirements for this system are surely similar to the ones of Profoto. Therefore I just tested it. Air Remote TTL-O connected to the camera and set to TTL. Flash switched on and put to full power. The camera pointed to a white wall and released. Lo and behold, the settings of the flash are automatically reduced and the white wall is taken neutral grey. Seems that both cameras are working with the Air Remote TTL-O.

Are both cameras compatible now?

No, they aren’t. As long as the cameras are not on the official Profoto website staged, they are not compatible. It is possible that the cooperation with the Air Remote TTL-O no longer works at any time. For example when one of the firmware versions will be updated and the communication with the Air Remote TTL-O will be adjusted. On this occasion, you don’t have any possibility to complain that the cameras have to work. In addition cover my short test, not all functions, which has to be covered to be compatible. For example, it could be that the high-speed sync is not working or the flashes are not 100% in sync. Therefore I would not recommend buying an Air Remote TTL-O in case you own a PEN E-PL7 or an OM-D E-M10 Mark IV. In case you already own one to use with a compatible camera you also could try it on a PEN E-PL7 or an OM-D E-M10 Mark IV. In case you do, please leave a comment underneath.

How to focus on a theme

Have you recognised that, if several photographers do together a photo walk, everyone brings different images back home? This is due to the different experience everybody has and therefore do recognise different things. Means photography has something to do with seeing, which can be learned with different methods. For example by using a theme when you are going onto a photo walk. This will sensibilities you and you will come back with different results than without.

Another option would be so called picture cards like the “Inspiracles” or “See the bigger picture”. This helps in case you don’t have ideas or you need inspiration.

Last but not least you could deal with a topic for a longer time this will change your perception.

Photo walk with a theme

Choosing a theme helps you to focus on a special topic and you will recognise motifs, which you otherwise missed. I do this from time to time and recognise after 2-3 hours, that I suddenly see only things fitting to the topic. For example with the photo walk “reflections”. In the beginning, it was hard to find motifs but was improving the longer the photo walk lasted. As we finished the photo walk suddenly I only saw reflections, even though that I was already on the way home.

Mirrored man
OLYMPUS DIGITAL CAMERA

Picture cards

The principle of picture cards is pretty simple. On the one side, you find information about the topic and a short description of how to realise it. On the other side examples, which should inspire you. You have two options in case you take images. Either you look through the cards and decide which one you are using, or, in my opinion, the more exciting, you just draw a card and just use the topic you get. In both cases, you will recognise, that it works to focus on one topic.

Deal with a topic

Especially in the last half-year, I recognise, that my way of seeing and how I take images has changed a lot. Due to the Covid pandemic, I have to work home a lot and therefore I went out during lunchtime to go through the park. Always a camera and a lens with focal length with me. The goal was to photograph local birds. In the first days, I heard the birds but was not able to see them. The more I deal with them, the more I saw the birds and was able to take images in the environment without feeding them. The highlight was, as I recognise a little bird while running on a small branch. Keen to know what it is I stopped and recognised that it was a nuthatch, which was flying to its nest.

Taking a coffee cup at home

Even if you have no studio equipment and have to stay at home, it is possible with simple tools to shoot beautiful images. Windows are perfect light sources and with some creativity, you can even handle to hard light. But first about my image. I had the plan to shoot an espresso cup with fresh, steaming coffee. Here my result.

First I looked for a suitable window that had enough light and set up my image. A wooden board from the kitchen served as background. A piece of fabric as a black background that I found in the closet. In theory, a t-shirt, duvet, or something similar would probably work as well. Since the light through the window was too hard, I had to think of something. Since I had no alternative, I cut up sandwich bags and stuck them to the window with adhesive tape. You can see this quite well in the next picture.

On the other side, you can see a brightener that I still had at home. If you don’t have something like this at home, you can alternatively use a simple piece of white paper. Coffee is made quickly and the cup, like it, is quickly put into the image. But I quickly discovered that the steam after the fresh brewing was not strong enough to be visible in the picture. So a creative solution was needed. First I tried a match, but unfortunately, the smoke was too strong. It looked unnatural. Then my son had the idea to light a coffee bean and let it burn until it glowed. This worked very well. The advantage is that you could put the bean in peace behind the cup and the smoke lasted long enough to take a picture.

Four influencing image quality factors of digital cameras

Introduction

In marketing, it is popular to have short and easy messages. Those short messages allow reaching a big target group, as nobody has to study the topic in depth. In the case of photography is this message “the bigger the sensor, the better the image quality.

At the time the first 35mm sensors, with the size of 36x24mm2, arrived in the market the manufactures called this format full-frame sensor. This name suggests to the end-user that this is the biggest available sensor and a clear statement, that the user buys the best available quality. In this communication, it is not mentioned that the sensor is only one of in total of four components, which are relevant for image quality

Beside the sensor three additional components are essentially important for the image quality. Lens, image stabilisation and image processor. How those components influence the image quality I will show with simple examples. I hope my thoughts demonstrate, that in photography sensor size is not the only value which the user should monitor to make the correct decision, if they plan to buy a camera.

The lens

Factors influenced by lens

  • Sharpness
  • Resolution
  • Contrast

The lens is the first element of the image quality chain and therefore the most important. In case your lens is not able to deliver details to the sensor, it is impossible that the result can show the details in the result. Due to the sensor specification, the lens requirements in digital photography are much higher than in analog times. Light rays, for example, should reach the sensor straight. Otherwise light rays which should reach i.e. the red pixel could reach the blue or green pixel. This would cause issues in colour processing, which should be avoided.
In analog time i.e. a 50mm F1.2 lens had 7 lens elements (Minolta Rokkor), today a modern 50mm F1.4 lens (Sony Planar T*FE 50mm F1.4 ZA) has 12 lens elements nearly twice as many. This value shows how big the development in lens technology has been since digital times started. As the lens is the most important element for image quality that some of the photographers invest most of their money in an expensive camera and not in the lens. In case the budget makes this decision necessary personally I would make it vice versa. In the end, you would keep the lens much longer as the camera.

The sensor

Factors influenced by the sensor

  • Sharpness
  • Image noise
  • dynamic range
  • resolution

After the lens, the sensor is the second element in the image quality chain. It has an influence on noise performance, dynamic range, and resolution, which means it influences the sharpness of an image. The sensor size influences the image noise and dynamic range only indirectly, but more in detail now.

Image noise / Dynamic range

If you want to look at the influence of the sensor size on the image noise you first have to make sure that technology improvements do not affect the result. Fortunately, I had a Sony Alpha 6000 and a Sony A7II available. Both cameras were introduced in 2014, so it can be assumed that the sensor manufacturing technology is the same. Also, both cameras have an identical number of pixels with 6000×4000 pixels. To find out how the results differ, I took a picture with both cameras, with the same lens and the same settings. The result looks like this.

Alpha 6000, ISO 25600
A7 II, ISO 25600

Even in the preview, you can see that the A7 II has a larger dynamic range than the Alpha 6000. This is especially noticeable in the mouth. If you look at an enlarged section, it quickly becomes clear that the A7 II is less noisy.

Alpha 6000, ISO 25600
A7 II, ISO 25600

It seems that the connection between sensor size and lower noise is confirmed and therefore most of the testers stop at this point with the comparison. But is really the truth? As the A7II as a function with which you can switch the area from 35mm format to APS-C format. In case the sensor size would have an effect this should be visible in images taken in this way. Let’s take a look at the comparison pictures.

A7 II APS-C setting, ISO 25600
A7 II 35mm format, ISO 25600

As you can see the dynamic range is identical in both images, but what is the image noise.

A7 II APS-C setting, ISO 25600
A7 II 35mm format, ISO 25600

Also, the noise is identical. Sensor size could not be the reason, that the noise performance of the Alpha 6000 higher is than the one of the A7 II.
The reason is the pixel size itself. As the Sony Alpha 6000 has the same pixel count on a smaller sensor area, the pixel itself is smaller, or in other words: the pixel density is higher. It isn’t as easy as it looks. The sensor size is no parameter for more or less noise performance, this has to be seen in conjunction with the pixel count.
The pixel size of an APS-C camera with 24 million pixels is equal to the pixel size of a 35mm format camera with 54 million pixels. Would I compare those cameras the noise performance would be identical.