Introduction

This blog is a user's perspective on the Micro Four Thirds camera system. Read more ...

Lens Buyer's Guide. Panasonic GH4 review.

My lens reviews: Olympus 9mm f/8 fisheye, Lumix G 12-32mm f/3.5-5.6, Leica 25mm f/1.4, Lumix X 12-35mm f/2.8, Lumix X 35-100mm f/2.8, Sigma 30mm f/2.8, Sigma 19mm f/2.8, Lumix X PZ 14-42mm f/3.5-5.6, Lumix X PZ 45-175mm f/4-5.6, Olympus M.Zuiko 45mm f/1.8, Panasonic Lumix G 100-300mm f/4-5.6, Panasonic Leica Lumix DG Macro-Elmarit 45mm f/2.8 1:1 Macro, Panasonic Lumix G 45-200mm f/4-5.6, Panasonic Lumix G 20mm f/1.7 pancake, Panasonic Lumix G 14mm f/2.5 pancake, Panasonic Lumix G HD 14-140mm f/4-5.8, Panasonic Lumix G HD 14-140mm f/3.5-5.6, Panasonic Lumix G 8mm f/3.5 fisheye, Lumix G 7-14mm f/4, Samyang 7.5mm f/3.5 fisheye, Tokina 300mm f/6.3 mirror reflex tele, Lensbaby 5.8mm f/3.5 circular fisheye lens
The blog contains affiliate links. As an Amazon Associate I earn from qualifying purchases.
Showing posts with label olympus. Show all posts
Showing posts with label olympus. Show all posts

Sunday, 15 November 2015

Fisheye lenses compared

I like fisheye lenses: They can cram an impressively wide field of view into the image frame, and create perspectives that you would not be able to see with the human eye. Another aspect of fisheye lenses is that they create a lot of barrel distortion (rounded images), which you can remove through a defish process, or retain in the final image.

Here is a collection of fisheye lenses for Micro Four Thirds and other systems:


From the left: Samyang 7.5mm f/3.5 (my review), Lumix G 8mm f/3.5 (my review), Yasuhara Madoka 180 7.3mm f/4 (my review), Olympus 9mm f/8 (white) (my review), Lensbaby 5.8mm f/3.5 (the biggest) (my review)

There are basically two types of fisheye lenses: A circular fisheye lens renders a circle in the centre of the image frame, which usually extends to 180° all around. A full frame/diagonal fisheye, on the other hand, renders the full imaging sensors, and usually extends to 180° from corner to corner.


Wednesday, 1 September 2010

Sharpness comparison, PL45 and ZD50

It's easy to find a lot of opinions about the Panasonic Leica Lumix DG Macro-Elmarit 45mm f/2.8 1:1 Macro lens and the Olympus Zuiko Digital 50mm 1:2 Macro lens. Generally, I have seen people saying that the 45mm is less sharp, but has better bokeh.


I have already compared the bokeh of the lenses, and while they are both completely adequate, is is probably true that the Leica Lumix 45mm has more smooth bokeh.

So I decided to compare the sharpness as well. For this study, I took a picture of a woolen scarf with some texture using both lenses. Here are the whole pictures, scaled down and sharpened a bit. Click for larger images.

PL45mm, f/2.8ZD50mm, f/2.8
PL45mm, f/5.6ZD50mm, f/5.6


I focused on the centre of the image. This was done manually for both lenses.

These images are not very well suited for judging the sharpness, though. We need to study some closeups of parts of the image. Here is the centre of the images, shown in 100% view, meaning that each pixel off the sensor becomes one pixel on the image. These images were not sharpened. Click for larger images.


f/2.8


f/5.6


Comparing the f/2.8 images might pose some problems. The lenses could be focused slightly differently. With the narrow depth of field at this aperture setting, this could lead to areas being out of focus in different ways. However, looking at the areas that are in focus, I think we can see that the contrast is a bit higher in the Panasonic Lumix 45mm image.

For the f/5.6 image, all of the cropped images should pretty much be in focus, with the wider depth of field. Again, I think it looks like the sharpness and contrast is a bit higher in the Panasonic Lumix 45mm image. But people might judge these images subjectively in different ways.

Conclusion

I think it looks like the Panasonic Lumix 45mm macro is slightly more sharp in this example. We should keep in mind that the Panasonic Lumix 45mm is more of a dedicated macro lens than the Olympus 50mm. After all, the PL45 has got higher maximum magnification. Also the Olympus 50mm has got a larger aperture, suggesting that it is intended to be used as a portrait lens as well. Hence, it could be that the Olympus 50mm is optimized for focus somewhat further away than the Panasonic Lumix 45mm is.

It should be noted, however, that in this example, both lenses are producing images that are sharp enough for most conceivable uses. Judging their relative sharpness in this case is very close to nitpicking.

In addition to this test, I have also studied the sharpness of the lenses at a longer focus distance.

Friday, 9 July 2010

Bokeh comparison, ZD50 and PL45

The Olympus Zuiko Digital 50mm f/2 macro and the Panasonic Leica Lumix DG Macro-Elmarit 45mm f/2.8 macro lenses are somewhat similar. The 50mm is a Four Thirds lens, and requires an adapter to be used on Micro Four Thirds (MFT) cameras. The Lumix Leica 45mm, on the other hand is a native MFT lens.

The Olympus 50mm is not optimized for Contrast Detection Autofocus (CDAF), and will autofocus slowly on MFT cameras, and not at all on the first series of Panasonic MFT cameras (G1, GH1, GF1). The Olympus has an edge when it comes to maximum aperture, one full stop faster than the Lumix Leica. On the other hand, the Lumix Leica has optical image stabilization built in.

Both lenses are useful both for macro photography and portrait photography.

This study looks into the bokeh (out of focus rendering) for a typical portrait setup. In the comparison, the subject, which is not a face in this case, is about one meter away from the camera. This corresponds to a headshot distance. The background foliage is about five meters from the camera. When taking a portrait under these conditions, it is important that the background is nicely blurred, and does not stand out to distract from the main subject.

I have previously compared the bokeh of the 45mm f/2.8 macro with two zoom lenses at 45mm, and looked at the bokeh for the 45mm f/2.8 macro at various apertures.

Here is the full image, taken at maximum aperture with both lenses. The images were taken within less than five minutes, so the lightning is mostly similar. I used a tripod, and ISO 100 in all the images. I used the P exposure mode, and auto white balance. The camera used was Panasonic Lumix GH1.

For both lenses I focused manually using the maximum enlargement. The images were rescaled and sharpened. Click on the image to view it larger.

Panasonic Leica Lumix DG Macro-Elmarit 45mm f/2.8

Olympus Zuiko Digital 50mm f/2

What's more interesting in terms of bokeh, though, is to compare 100% views of various regions at the same aperture.

Here is the centre at f/2.8 (click to enlarge):

The centre at f/4 (click to enlarge):

The centre at f/5.6 (click to enlarge):

Here's also 100% crops from the lower left corner. Since the field of view is not exactly the same for the two lenses, the crop might not be from exactly the same area.

The corner at f/2.8 (click to enlarge):
The corner at f/4 (click to enlarge):
The corner at f/5.6 (click to enlarge):
Conclusion

Honestly, I was expecting the Olympus 50mm lens to perform best in terms of bokeh. This study, however, shows that the bokeh is somewhat smoother with the Lumix Leica 45mm. The highlight circles have harder edges with the Olympus 50mm.

Both lenses are certainly very capable, though.

Sunday, 16 May 2010

Cheap and simple macro soft box

When taking macro pictures, or pictures of fairly small objects in general, a common problem is to get the lightning right. More even lightning can be achieved by using a "soft box", essentially a contraption that spreads light from one (or a few) light sources over a larger area.

A very cheap and simple soft box is a transparent bucket, like this one:

Preferably, it should have as neutral density as possible. If it has some colour tint, the images will get the wrong white balance. It is of course possible to adjust the white balance later, especially if you're using RAW images, but it is better to have as correct colours as possible from the start.

When photographing the object, place it inside the bucket, with the light source on one side, or from the closed end, like this:

In this case, I used a Panasonic Lumix GH1, with an Olympus 50mm f/2 macro lens. This combination can only be focused manually, which is no problem for macro use.

The light source is simply the sun light coming from the window on the top side of the image. One could also have used a flash pointing towards the side of the bucket, however, an off camera TTL flash would have been preferable, which is probably not so common for people to have for this system.

Here is an example picture, taken with (left) and without (right) the softbox. As you can see, the softbox image has softer contrasts. Besides, the picture taken without the softbox has reflections from the window. The right image also has some shadows next too the feet, which you may need to edit out later.

I used ISO 100, f/5.6 for both images. The shutter speed was 1/3.2 second for the left image, and 1/5 second for the right image, since the softbox steals some light.

Here is another example image, showing a Pelikan M425 piston filler fountain pen. I used f/13 to achieve enough depth of field.

Monday, 5 April 2010

Portrait lens

Traditionally, a portrait lens is one that has around 85-105mm focal length (35mm equvivalent), and a fast aperture to allow shallow depth of field to blur the background. The closest we have at the moment in the Micro Four Thirds lens lineup is the Olympus M.Zuiko Digital 45mm f/1.8 prime lens.

The fast aperture is easy to understand. At a small, slow aperture, the background will be less blurred, and will distract the viewer from the main focus of the image: The face. So you will want a fast, large aperture to blur the background and avoid distracting elements in the background.

But how about the focal length? To study this, I have photographed the same face with various focal lengths from 9 to 70mm with the Panasonic Lumix GH1 and the Lumix HD 14-140mm lens. I also used the Olympus Four Thirds 9-18mm wide angle zoom lens for the first picture. This corresponds to 18mm-140mm on traditional film based 35mm cameras. The distance from the camera to the face was shortest with the shortest focal length. As I zoomed in, I needed to step backwards.

Here is the series of photos:
9mm

14mm

18mm

25mm

35mm


50mm

70mm

As you can see, in the first pictures, the perspective is distorted. The nose appears much too large. This is not due to any flaw in the lens, or due to the camera, but due to the fact that I needed to get very close to make the face fill the entire frame at 9mm focal length.

So close, in fact, that the lens was not able to focus close enough. To get the face reasonably in focus, I focused as close as possible, and used a small aperture to make the depth of field wide. The bicycle in the background is almost in focus in the first images, due to the small aperture.

The distorted perspective is due to being close to the subject, to fill the face into the entire frame. You would get the same distorted image if you looked at the face with your own eyes, given the same distance. But you don't normally get so close to someone's face.

The first frame is obviously distorted. The last one looks normal. I would say that the one taken with 35mm focal length also looks slightly distorted. So to achieve enough distance to the subject to avoid a distorted perspective, you need approximately 50mm focal length on Micro Four Thirds.

You could use a smaller focal length as well. If you still keep some more distance to the subject, you could get the face to fill just some part of the image, and be distortion free. But such a picture would not be a portrait.

This is exactly the reason why traditional portrait lenses are around 85-105mm, corresponding to about 42-53mm of Micro Four Thirds.

Panasonic Leica 45mm f/2.8 1:1 macro

Based on this, you will understand that the choice of focal length for the Panasonic Leica DG Macro-Elmarit 45mm f/2.8 1:1 Macro Mega O.I.S. was no coincidence. 45mm corresponds to a portrait lens for Micro Four Thirds, and gives you enough distance to the subject for taking distortion free portraits. However, the aperture size, at f/2.8, is not really large enough to isolate the background from the face. f/2 or larger would have been desirable.



Olympus 45mm f/1.8

In the summer 2011, Olympus launched a true portrait prime lens for the Micro Four Thirds system, the Olympus M.Zuiko Digital 45mm f/1.8. While I'm sure some will still be disappointed with the maximum apeture, it could have been even larger at f/1.4, for example, I think this is the best portrait lens for the format at the moment.



Panasonic 20mm f/1.7

The Panasonic Lumix 20mm f/1.7 is a popular lens for taking available light pictures of people, but it is not a portrait lens. You cannot fill the subject's face in the entire frame and avoid distortion with this lens. With that said, the lens is very sharp, and you should be able to get away with stepping back a bit, and cropping the picture later. This is not an optimal solution, but it should work well in many cases.

The Panasonic Lumix 20mm f/1.7 lens is also good for taking environmental portraits.



Olympus 50mm f/2 1:2 macro

On the other hand, the Four Thirds lens Olympus 50mm f/2 macro can be considered a portrait lens. The focal length is in the correct range, and the aperture is large enough to blur the background sufficiently.




All kit lenses include the typical portrait focal length area. Both the Olympus 14-42mm and the Panasonic 14-45mm extend to around 85-90mm in 35mm film equivalent. However, at the maximum tele, the aperture is not very impressive at f/5.6. With this aperture, you need to check the background, and try to make sure it does not distract too much from the main subject, the person.

Panasonic 45-200mm f/4-5.6

The Panasonic Lumix 45-200mm f/4-5.6 Mega O.I.S. does cover the typical portrait field of view. However, with a maximum aperture of f/4 at 45mm, it can not really be considered a genuine portrait zoom. With f/4, you need to watch the background to make sure it does not distract too much. If the background is even, though, I see no reason why you should not use it for portraits.

Other tele zooms can be used in the same way, e.g., the Lumix X 45-175mm f/4-5.6, Lumix G 45-150mm f/4-5.6 and the Olympus 40-150mm f/4-5.6. Normally, one would want to pair tele zoom lenses with cameras of the same brand, i.e., use a Panasonic lens on a Panasonic camera. The reason is that Panasonic cameras don't have built in in-camera image stabilization, like the Olympus cameras do.






Panasonic Leica 25mm f/1.4

The Panasonic Leica DG Summilux 25mm f/1.4 Asph lens corresponds to a "normal" lens on a traditional film camera. While it is longer than the 20mm pancake lens, it is still not a portrait lens. If you go close enough to fill the face of the subject into the entire frame, then you are too close to get a distortion free image. On the other hand, with the slightly longer focal length, it is certainly better suited for low light photos of a person's face and shoulders.



On 35mm film based cameras, a portrait zoom is typically 70-200mm f/2.8. This lens allows portraits at various distances, with a minimum of distortion, and reasonably blurred background. In the Four Thirds system for DSLR cameras, the Olympus 35-100mm f/2 is a typical portrait zoom. For the Micro Four Thirds system, there is the Lumix X 35-100mm f/2.8, which can be called a portrait zoom.



For APS-C DSLR cameras, portrait zooms typically have 50-135mm f/2.8 specifications. Pentax, Tokina and Sigma have lenses in that category.

Tuesday, 23 March 2010

Four Thirds lens compatibility

Panasonic Lumix Micro Four Thirds (MFT) cameras can use all Four Thirds (FT) lenses, provided that you use an adapter. You can use either the Panasonic DMW-MA1, or Olympus MMF1/MMF2 adapters.

However, you should note that not all FT lenses will autofocus on Panasonic MFT cameras. Only fairly recent lens designs that are prepared for contrast detection auto focus (CDAF), will work. The compatible FT lenses are



These lenses will autofocus on Panasonic Lumix MFT cameras, like G1, GH1 and GF1.

Newer Panasonic cameras like GH2, G2 and G10 feature some improved autofocus functionality using some FT lenses. For example, the GH2 can autofocus using the Olympus 50mm Four Thirds lens, but the focus is very slow. The Panasonic G1, GH1 and GF1 will not autofocus this lens at all.

All Olympus MFT cameras can autofocus with all FT lenses, so Olympus camera users can ignore this list. This also goes for Panasonic FT lenses used on Olympus MFT cameras. The autofocus can be very slow with some FT lenses, though.

For those combinations of lenses and cameras where autofocus works, you will still experience slow autofocus with FT lenses on both Panasonic and Olympus MFT cameras. I have made a comparison of autofocus speeds using some MFT and FT lenses on the Panasonic GH1. Also, a similar comparison for the Panasonic GH2.

Even if autofocus does not work on some camera/lens combinations, other functions like aperture control will still work. And using manual focus is not that difficult. Here is an illustration of using manual focus with Olympus 50mm f/2 macro on Panasonic Lumix GH1.

Sunday, 14 March 2010

Macro extension rings

Using macro rings has always been a cheap trick to improve the close focusing distance of a lens. You'll notice that when focusing from infinity to a closer distance, the lens elements usually move away from the camera and the sensor. Some exceptions from this are lenses with internal focusing, or back focusing.

So what happens if you move the lens even further from the camera than what's possible with the focus ring? It turns out that this gives you an even closer focus. So what a macro extension ring simply does, is allow you to mount the lens further from the sensor, translating the focus range of the lens so that it can be used for close up work.

There are no macro rings officially available for the Micro Four Thirds mount yet. However, when using legacy lenses on an adapter, there are a wide range of macro rings to try out. Here is a set of Nikon macro rings from Jessop:

These rings contain some mechanical coupling functions to allow for the aperture information to be transfered to the camera, and for the camera to automatically stop down the lens before taking a picture. However, these functions only work on AIS capable cameras. In today's Nikon lineup, only the top models have retained this functionality.
When using the rings on a crude adapter, you can certainly forget about this functionality. You'll need to focus using a large aperture, and then alter the aperture ring manually prior to pressing the shutter release, if you want to stop down the aperture.
The thickness of the rings are 13mm, 21mm, and 31mm. When stacked in different combinations, they can give these offset distances: 13mm, 21mm, 31mm, 34mm, 41mm, 52mm and 65mm.

Normally, these rings would go between the camera mount and the lens. When using an adapter, however, they go between the adapter and the lens, as in this picture:



A Nikon-Micro Four Thirds adapter (marked with "Nik-M4/3") is mounted to the Panasonic Lumix GH1 camera, and all the macro rings are stacked between the lens and the adapter. The lens is a Nikkor 50mm f/1.8 AIS. Here is a video showing how to attach the adapter and lens to the camera.

When using all the macro rings above, I took this picture of a measure band, to find the largest magnification. It was taken at 4/3 aspect ratio, in which case the active sensor is 18mm wide. Since the photographed item is 13mm wide, this gives an enlargement of 18:13, or 1.4:1. This could also be expressed as 1.4x.



For comparison, the Panasonic Leica DG Macro-Elmarit 45mm f/2.8 macro lens is capable 1:1 enlargement (1x), which means that the largest enlargement possible would have yielded 18mm of the measurement band. The macro rings and Nikkor 50mm lens can be used to make more enlargement than the dedicated Panasonic Leica macro lens.

Using the configuration above, with 65mm extension of the lens, I was able to take this close up picture:


I stopped down the aperture to f/8 for more depth of field.

For comparison, I photographed the same object using the Olympus Zuiko 50mm 1:2 macro lens. This is the closest picture I could take with the Olympus lens, also at f/8, and with an enlargement of approximately 1:2:



Macro rings for legacy mounts can be bought cheaply on various auction sites. There are also extension tubes and bellows, which are functionally similar, but more flexible in use. Another way to achieve closer focusing is to use a reverser ring, essentially a second lens mount to be screwed into the front lens filter thread. Using a reverser ring, the lens can be mounted reversed, in which case it can be used for macro. Lenses with a normal focal length are most commonly used this way.

Please note that macro lenses are special in that the lens formula is designed for close up photography. Using ordinary lenses on extension rings or bellows is not going to give as good results, since those lenses are not designed for close focusing.
Here is another example picture using the full 65mm macro ring extension:



For this picture of a garlic, I used f/22 to achieve enough depth of field. Using such a small aperture is going to give some blurring at pixel level due to diffraction. However, in this case, I valued more depth of field higher than some dullness at the highest magnification. The diffraction effect is barely visible at 100% view.

Sunday, 10 January 2010

Wednesday, 6 January 2010

Four Thirds system

The Four Thirds systems is a DSLR camera system originally developed by Olympus and Kodak. The first Olympus camera was announced in 2003 (the professional grade Olympus E-1), along with four lenses.

While the major players in the DSLR camera market based their digital cameras on their existing film camera mounts and lenses, Olympus did not have a significant user base at this time, and found it better to design a new system from ground up, based on the requirements of digital photography.

Aspect ratio and sensor size

The name "Four Thirds" cleverly refers to two things at the same time:

  • The image aspect ratio. While the aspect ratio of 35mm film cameras is 3:2, the Four Thirds system has a more square aspect ratio of 4:3. There are many reasons for this, e.g., a typical print size is 8:10, with a more similar aspect ratio to 4:3. And professional medium formats are typically closer to square aspects, like 4.5x6, 6x6 and 6x7. However, since the introduction of Four Thirds, formats that are even wider than 3:2 have become popular. TV sets are now typically 16:9. I still think that 4:3 makes sense for photography. A more square format uses the image circle more efficiently, which is an advantage, assuming, of course, that you're not going to crop it down to a more rectangular format.
  • The size of the sensor. The sensor has the same size as the imageing area of a 4/3'' diameter legacy cathode ray tube for video cameras. The actual size of the sensor is still significantly smaller than 4/3'', with the diagonal of the imaging area usually being 21.6 mm.
The Four Thirds sensor size is about 30-40% smaller than the APS-C sensors commonly used in other DSLR systems. This has various consequences:

  • In theory, a smaller sensor usually means worse high ISO capabilities, and worse dynamic range characteristics, given the same number of pixels, and the same sensor technology.
  • The depth of field is larger with a smaller sensor. This means that given the same distance, field of view and aperture, more will be in focus with a smaller sensor. This is both an advantage and a disadvantage. In landscape photography, you will most often want sharpness across the image, and a wide depth of field. On the other hand, in portrait photography, it is often desireable to have a narrow depth of field, to achieve isolation of the subject, and blurring of the background.
  • A smaller sensor will limit the useful range of apertures more, due to diffraction, again assuming the same number of pixels. Diffraction will make the image blurry at pixel level when using small apertures. This is not due to bad design, but rather the result of the laws of nature.
  • Designing lenses and cameras around smaller sensors is in some ways easier: They can be made more compact.
  • A small sensor gives a higher crop factor. The crop factor of the Four Thirds sensor is roughly 2x, meaning that the focal length in mm for a Four Thirds lens must be multiplied with 2 to get the equivalent focal length on a traditional 35mm camera. Hence, a 14mm lens on Four Thirds is a wide angle lens, corresponding to 28mm on a traditional film camera. Some suggest that with this background, systems with a high crop factor are good for people who need long lenses, e.g., for wildlife photography. However, there are lenses to suit virtually all needs in the Four Thirds system.


Lens design

Another important aspect of the Four Thirds mount is the register distance, also called the flange focal distance. The register distance is the distance between the lens mount and the sensor plane. With the sensor size being smaller than for other DSLR systems, the Four Thirds system also has a smaller register distance. This aspect of the camera systems makes designing lenses, especially wide angle lenses, easier.

Olympus lenses are commonly more telecentric than lenses from other systems, especially lenses that were originally designed for film. The telecentric property of a lens means that the light rays coming from the lens hit the sensor at a more normal angle across the field, especially in the corners. This is important for digital photography, since the sensors are sensitive to the angle of the light rays: If the light rays are hitting the sensor at a narrower angle in the corners, a significant portion of the light will be lost in the sensor pixel bins, giving heavy vignetting. More telecentric lenses generally give less vignetting in the corners. However, designing telecentric lenses is more complicated, and some of the size advantage of the smaller sensor is lost with this property of the lenses.

History

The original cameras in the Four Thirds system were not so compact, and, while they were innovative, they were also somewhat strange looking. Later, Olympus launched smaller cameras, with the E-4xx series being the smallest DSLRs on the market at the time of availability. The cameras have also been more traditional looking after the first two-three years. After some years of maturing, the Olympus DSLRs are not very different from the competitors, beyond being somewhat smaller.

Panasonic and Leica have also issued cameras in the Four Thirds system, however with major components Olympus sourced. The Leica branded cameras have largely been similar to Panasonic models, with smaller changes to the design and software. Since this time, both Panasonic and Leica appear to have withdrawn from the Four Thirds system, with Panasonic focusing more on the newer and more compact Micro Four Thirds system, and Leica designing their own high end cameras, e.g., the Leica X1. Leica still appears to have some involvement in the design of lenses for the Micro Four Thirds system, with the Leica branded 45mm f/2.8 macro lens launched in the autumn 2009.

A new standard was announced in 2008, the Micro Four Thirds. This shares the sensor size with Four Thirds, however, leaving no room for a mirror assembly. Panasonic G1, the first camera for this standard, was launched in the autumn 2008. The new system has been very successful in Japan, and Panasonic cameras and lenses have been scarce in Europe and especially the US in 2009, suggesting a high demand.

According to the statistics quoted above, the Olympus E-P1 Micro Four Thirds camera was the most selling Olympus camera model in Japan 2009. This has prompted some concern that Olympus might discontinue the regular Four Thirds line, and focus exclusively on Micro Four Thirds. I think the chances for this are slim at the moment, since Olympus has a large and good back catalogue of Four Thirds lenses. While the E-P1 camera has sold a lot, I am sure that they have sold a lot of Four Thirds lenses as well, not recorded by the statistics.

Saturday, 2 January 2010

Manual focus with Lumix GH1

Here is a video that illustrates how manual focusing is done with the Panasonic Lumix GH1 camera. The Olympus 50mm f/2 macro lens is attached to the camera through the Panasonic DMW-MA1 adapter. The adapter is needed since the lens is a Four Thirds standard lens. No autofocus is possible with this combination.



When powering on the camera, it prompts you to switch to manual focus mode. This is not needed. You can leave the camera in autofocus mode, however, no autofocus is possible, of course.

Turning the focus dial will enable the zoomed view. What you see now is a 5x magnification of the centre of the image.

Tapping the shutter release gently brings up the normal full view again.

In the magnified focus assist view, you can use the front dial to switch between 5x and 10x magnification. You can also use the arrow buttons to move the magnified area around, in case you do not want to focus on the centre of the frame.

When you power down the camera, the lens will retract to infinity focus.

It would have been good to have a dedicated button to alter between the magnified focus assist view, and the normal view. While you can bring up the normal view by tapping the shutter release, turning the focus dial, which you may not always want to do. You could also use the focus area button on the rear, and then press OK, which brings up the zoomed view.

Olympus Zuiko Digital 50mm 1:2 Macro

This is an unusual lens. Not only is it a macro lens capable of photographing subjects as small as 2x the sensor size (hence the 1:2 designation), but it is also a fast short tele suitable for portraits, with a maximum aperture of f/2. The focal length is 50mm, however, with the 2x crop factor associated with Four Thirds, it will have the same field of view as a 100mm lens on a traditional 35mm camera.

Since this is a Four Thirds standard lens, it cannot be used on a Micro Four Thirds camera without an adapter. It is shown here with the Panasonic DMW-MA1 adapter attached. The Olympus MMF1/MMF2 adapter would have done the same job, as it is functionally the same, albeit usually somewhat more expensive at retail.

Focus

Unfortunately, you cannot use autofocus with this lens together with the first series of Panasonic Micro Four Thirds camera bodies (G1, GH1, GF1). The Olympus cameras, and newer Panasonic cameras, on the other hand, can do autofocus with this lens, albeit operating at a slow speed. Here is a demonstration of the autofocus using Panasonic GH2, which takes five seconds to focus down to 45 cm distance:



Here is a demonstration of manual focusing with this lens on a Panasonic Lumix GH1.

Some Four Thirds lenses can autofocus on Panasonic Micro Four Thirds bodies.

The closest focus distance is 0.23 m. Be aware, though, that the focus distance is measured from the focal plane (the sensor), and so the distance between the front lens and the subject at closest focus is about 0.1 m.

The lens is also special in that it is one of the few Four Thirds lenses that feature a focus scale.

Size

Compared with the Lumix G 20mm pancake lens, the Olympus 50mm macro, including adapter and hood, is enormous. However, it is of course more natural to compare it with other 100mm equivalent macro lenses, in which case it is remarkably compact.



It is somewhat smaller than the Lumix G HD 14-140mm kit lens.

Macro lens

Most macro lenses have a maximum aperture of f/2.8 or slower, e.g., Sigma 105mm f/2.8 and Tamron 90mm f/2.8, both in the same focal length range. Hence, a f/2 macro lens is unusual, and some might say this speed is not needed. You would rarely photograph small subjects with such a large aperture, since the depth of field (DOF) becomes very narrow. Unless the subject is more or less flat, only a small part of it will be in focus at f/2. Stopping down to at least f/5.6 may be needed to have a sensible depth of field at close focus.

Here is a series of photos that illustrate the depth of field at 25cm distance, and various aperture sizes. The focus is set to the centre face. The distance in the axis of the lens between the three heads is one LEGO unit, or 8mm, if your not familiar with this measure. You must stop down to f/16 to get a depth of field that covers this distance.









At such a small aperture as f/16, you are going to see some lack of sharpness at the pixel level due to diffraction. You may still choose a small aperture like this, however, if you need a wide depth of field, and can live with some dullness at pixel level. For web use, for example, where you will normally scale down the image, this should not be any problem.

In macro photography, it is uncommon to use autofocus, since you will need to fine tune the focus anyway to get the desired effect. So the lack of autofocus on Panasonic Micro Four Thirds cameras is not a problem for macro photography.

Bokeh

I've made a study of the bokeh of the lens. My conclusion is that the bokeh is very pleasing, although the out of focus highlights have a somewhat hard edge. But in general, you're unlikely to be dissatisfied with the bokeh using this lens.

Portrait lens

When taking headshots, it is common to keep some distance to the subject. This is done to avoid perspective distortion. Taking a picture of someones face from a short distance will usually give unwanted distortions, e.g., showing an unnaturally large nose or a large chin. Traditionally, an 85mm lens has been used on a 35mm camera to be able to fill the head and shoulders of a person in a picture frame, and still keep enough distance to the person to avoid perspective distortion. The Olympus 50mm macro lens corresponds to 100mm focal length on a 35mm camera, and so it is useful for portraits.

A traditional portrait lens will be around 85mm f/1.4. The Olympus 50mm macro has one stop slower aperture at f/2, but it is still large enough to isolate the background when taking portraits.

In studio photography, the lack of autofocus is not likely to be a problem. If you're photographing people in a more dynamic environment, you may see the need for autofocus.

Other uses

You could also use this lens for concert photography, given that you're placed not too close to the stage, and the people on the stage are not moving around too much. If you've got something to rest the lens against, you may be able to use longer shutter speeds.

Sharpness

This lens is generally considered to be among the best in the Olympus Four Thirds lineup. It is remarkably sharp from f/2, but close it down a bit for even better sharpness. At f/5.6 it is probably around the sharpest.

Chromatic aberrations

I have made a study of the chromatic aberration (CA) artifacts of this lens, and some other prime lenses. It shows that there are quite some red/green fringing artifacts even in the centre of the image. You will note this if you photograph high contrast images.

Image stabilization

Using this lens with a Panasonic Micro Four Thirds camera, there is no image stabilization available at all. You'll normally want to use a fairly short shutter speed, e.g., 1/60 second or faster, to avoid camera shake affecting the image when handholding the camera.

Olympus Micro Four Thirds cameras have image stabilization built into the bodies, which will work with this lens.

It is perfectly possible to use this lens when recording videos. However, you can only focus manually on Panasonic cameras. With the lack of image stabilization, and a pretty long focal length, it is more or less impossible to handhold the camera stably while recording movies. Using the electronic viewfinder and pressing the camera against your face may help you to stabilize it a bit. But using a tripod is preferred when filming with this lens.

Hood

The lens comes with a bayonet hood, to protect against stray light. I found the hood to be a tad bit long, making it difficult to fit the camera with lens and hood inside my small camera bag, so I chose to use a 52mm screw-in hood from B+W. The hood also protects the front lens element from objects touching it accidentally.



Example picture


Here is an example picture of a broken Leatherman tool taken at maximum magnification (closest focus distance), f/10, 1/5 s, ISO 100.



Other macro options

It is also possible to achieve macro close up photos by using macro extension rings.

Another, more expensive, option is to use the Panasonic Leica Lumix 45mm f/2.8 1:1 Macro lens, which is a native Micro Four Thirds lens.

Friday, 1 January 2010

Market shares in Japan

Update: I have compiled newer statistics based on 2010, which supersede this material.

The Japan market shares are usually published every year. The figures comprise system camera units sold in Japan, mostly DSLRs, but the new Micro Four Thirds cameras are included as well. Only the 20 camera models with the largest sold volumes are included in the statistics. Other camera models, with less sales than these, are in the "Others" category.

I have concatenated the 2009 statistics (as at Dec 23rd) with the 2008 statistics, to be able to see the development better:



To make it easier to digest, I have split the figures into camera systems:



Before starting to comment on these figures, it is useful to note that the "Others" category is larger in 2009. This means that the volume of the smallest camera models has increased. We don't know how large the volume of various camera systems are here, but it is reasonable to guess that we would find some more Olympus, Sony and Nikon models in the 2009 "Others" category.

Canon has held their market share remarkably well. It is also worth noting that the full frame camera Canon 5D Mark II has a fairly high market share at 2.1%.

Nikon appears to have lost significant market shares, which must be very bad news for them. On the other hand, it is reasonable to guess that they have somewhat more volume in the "Others" category in 2009, with, e.g., the Nikon D300 and Nikon D700.

Sony must also be very disappointed, with less than 50% of the 2008 market shares. Again, though, they probably have more camera models in "Others" in 2009.

Pentax have succeeded with their strategy of launching entry models packed with features.

Olympus have only got one Four Thirds model in the 2009 list of the twenty most sold camera models, compared with three in the 2008 list. On the other hand, the E-P1 camera has been very popular, and made up for the lost Four Thirds units.

The Micro Four Thirds system has a total of 11.5% of the new sales in Japan in 2009, which I think is very remarkable. After all, the system was launched in 2008, and only two small players in the system camera market are behind it.

2007

For the fiscal year 2007 (actually only January through November), I could only find DSLR sales in summary form: Nikon 43.3%, Canon 39.9% and Pentax 6.3%, with the other producers being smaller.

2006

This table contains DSLR market shares in Japan by December 2006, for the largest ten camera models. I find it hard to believe that the D40 has already captured 15.5% of the total market in December 2006, since it was introduced the same month. However, this table might have been adjusted for the introduction time of each model.



Summary 2006-2009

All of this information can be summarized into one table, but please be aware that the numbers are not entirely comparable from year to year. Still, there is a trend to be seen.



2005-2009 from another source

BCNranking has published statistics for the three most sold brands within interchangeable lens cameras, meaning DSLRs and hybrid systems like Micro Four Thirds. This table shows the same trend as the other material:



We can see that while Canon has had a stable marked share the most recent years, they have actually had a significant decline when looking back five years. Also, Nikon had a good period around 2007, probably due to the launch of D40, but has not been able to sustain the growth.

Panasonic is the big surprise in 2009, with a third place due to the Micro Four Thirds bodies, probably mostly the G1, having been on the market for the whole 2009.