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.

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

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.

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 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 its 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.

Fast selection of images

When using a function like continuous shooting mode, ProCapture or Focus Bracketing you get very fast a lot of images. The SD card gets filled up very fast and not every image is needed. The normal way to delete single images is very time consuming and therefore not helpful. Cameras from the E-M1 series have fortunately a function to easily select many images in a short time.

1. Press the replay button to see the images on the SD card

2. Use the thumbwheel to switch from the single image view to the thumbnail view.

3. Select the first image, which you would like to select. Press and hold the movie record button.

4. Rotate either the forefinger wheel or thumbwheel to select the other images. You can select up to 200 images.

As soon as you have selected the images you can either delete or mark them as protected or share them with OI.share.

Olympus PEN E-P7 introduction

In 2009 Olympus introduce in Berlin the E-P1 the first mirrorless camera with Micro Four Thirds standard. Already at that time, the camera design was based on the PEN design in the late sixties. Several successors have been released and in 2013 the last PEN of the P series has been released. Now after 8 years, OM Digital Solutions pick up the threads and releases with the E-P7. Its design doesn’t require hiding from its predecessors. Modern but classic looks pretty nice and OM Digital Solutions achieved once again a very attractive camera.

Olympus PEN E-P7 with M.Zuiko Digital 12mm F2.0

The inner values

Personally, I love the design and this is already a good reason to buy the E-P7, but the E-P7 is coming with the newest technologies. It has the current image processor TruePic VIII and brings a 5 axis image stabilisation, which can correct 4,5 EV steps. In addition, it is the first PEN with the known 20 MPixel sensor of the E-M10 Mark IV. In conjunction with the high-quality M.Zuiko lenses, the E-P7 can deliver the best possible image quality.

What I like about the E-P7 most are the creative possibilities. Besides the well know Art Filters and the long time exposure function Live Composite and Live Bulb, the E-P7 is coming with Monochrom Profile and Colour Profile Control, which is known from the Olympus PEN-F. For both profiles, the E-P7 comes with four presets, which could be adjusted to personal preferences. The creative functions can be combined. For example, you can combine the Monochrom Profil or Color Profile with Live Composite and LiveBulb. This enables you to create unique results without long time post-processing.

The target group of the E-P7 are those who are using the smartphone to take images and looking for a camera with interchangeable lenses to be more creative. Therefore is the camera compatible with OI.share, with which you can remote control the camera. In addition, it is possible to transfer images directly from the camera to the smartphone. New in the E-P7 is, that you can transfer taken images automatically to the smartphone. Now it is even easier to transfer images to your smartphone and share them on social networks.

Olympus PEN E-P7 white

Critics

As beautiful as the camera is there are some features which will not be liked by all of you. For example, the display is only tiltable by 80° up and 180° down. It is also no swivel display. As the display is tilted downwards to see it from the front it is not possible to use a tripod. This makes selfies and selfie movies more difficult. OI.share can help here, as the live view can be used to control the image.

In addition, the E-P7 doesn’t have an electronic viewfinder. A lot of photographers do prefer an electronic viewfinder, especially when they are taking images in bright surroundings or need reading glasses. Here is a viewfinder helpful as the image is shown in infinity. The missing viewfinder is the reason for the compact size of the camera, which enables you to have the camera always with you.

Conclusion

All in all the E-P7 is a very nice camera. Especially using the creative functions is fun and enable you to create impressive images without post-processing. This helps you to share your own image styles fast and uncomplicated on social networks. Due to the small size and weight, it competes with a camera like the Canon GX7 with the advantage of interchangeable lenses. In case you own already a Micro Four Thirds camera, the E-P7 is certainly an option as a second camera.

My experience with the M.Zuiko Digital ED 8-25mm F4.0 PRO

Photographers like landscape photography. It has only a few entrance requirements and, as nature is not moving fast, you have enough time to shoot and you don’t have to know your camera in detail. The M.Zuiko Digital ED 8-25mm F4.0 PRO is the third wide-angle zoom from OM Digitalsolutions in the Micro Four Thirds standard, Even though that Panasonic has also three wide-angle zooms in their portfolio, the new lens is worth thinking about it. Especially in landscape photography, an open aperture of F4 is not a disadvantage.

M.Zuiko Digital ED 8-25mm F4 PRO top view

Inner Values

The biggest advantage of the lens is the huge zoom range. With 8mm is covers the ultra-wide-angle area and it reaches 25mm the normal area. Therefore it is not only usable in landscape photography, but also for street and portrait photography. In opposite to the 7-14mm lens from Olympus, the front lens is plane and normal filters without a special adapter are useable. The filter diameter is 72mm the same as the one from the 12-100mm, 40-150mm and 100-400mm lens. In case you already own a filter in this size you can reuse it for the 8-25mm as well. In case the filter thickness is less than 4mm you won’t have any vignetting.

The lens is equipped with a retracting mechanism to be as small as possible in case you would like to transport it. In opposite to the 9-18mm lens the 8-25mm lens doesn’t have a button to unlock the retracting mechanism, but a very defined resistance, which has to be overcome to make it small. This reduces the complexity of construction and makes it easier to make the lens weather resistant. The disadvantage of this mechanism is that the length of the lens is also changing when you zoom.

Although the 8-25mm lens covers a much bigger zoom area than the 7-14mm it is even smaller and lighter. As all Pro lenses of OM Digital Solutions, the 8-25mm is weather-resistant and freezeproof down to -10°C.

M.Zuiko Digital ED 8-25mm F4 @8mm
M.Zuiko Digital ED 7-14mm F2.8 @7mm

Besides the focus ring, which could be used to switch from autofocus to manual focus by pulling it back, the lens has also a programable function button.

Image quality

As all Pro lenses from OM Digital Solution delivers the 8-25mm lens already at open aperture outstanding image quality. Also in the image corners, which are losing only a bit in sharpness. From aperture 11 onwards the lens is getting softer. This is caused by diffraction. In case you would like to have the highest resolution possible I recommend not using smaller apertures than 11. In case you would like to have a bigger depth of field, focus stacking and focus bracketing is supported with the E-M1X, E-M1 Mark III, E-M1 Mark II and E-M5 Mark III in case the newest firmware is installed.

Resolution and sharpness are on the same level as the M.Zuiko Digital ED 7-14mm F2.8 PRO and also don’t have to be worried about any other lenses.

Distortion is from 25-12mm no issue at all. In case you are using a shorter focal length barrel distortion becomes visible in RAW converters which don’t use the attached lens profile. In case you are using the profile this distortion is perfectly corrected.

Conclusion

The third ultra-wide-angle zoom from OM Digital Solutions is unique. It covers not only the ultra-wide-angle area but with 25mm it is covering the normal focal length as well. Therefore it is very universal and the image quality is in all areas superb. In the wide end, it has one millimetre less than the M.Zuiko Digital ED 7-14mm F2.8 PRO and in case you don’t shoot nightscapes you will not miss the 1 f-stop. Though is the M.Zuiko Digital 8-25mm F4.0 PRO smaller and lighter than the M.Zuiko Digital ED 7-14mm F2.8 and it is its biggest internal competitor. In case you are shooting landscapes or architecture, I personally would prefer the 8-25mm over the 7-14mm. Also for photographers, who are travelling much and would like to reduce weight and size as much as possible the 8-25mm lens is the better choice. Although it is not essentially smaller and lighter than the 7-14mm lens, it allows leaving one lens behind due to the huge zoom range.

You get the best Balance in case you are using cameras from the E-M1 series or E-M5 series. Smaller cameras like the E-M10 series doesn’t fit so well, here the 9-18mm lens fits better.


Great usages report from Peter BaumgartOlympus Amerika Webite

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.