Wednesday, 27 August 2014

Wide angle prime lenses compared

The classic 28mm prime lens is a natural part of any lens lineup. Most kit zoom lenses include the 28mm equivalent in the wide end, but you can also get prime (non-zoom) lenses with the same field of view.

Below are three such lenses, for three different interchangeable lens systems. How do they compare?


From left to right: Sigma 19mm f/2.8 (old style) mounted to a Sony NEX-3N, Lumix G 14mm f/2.5 mounted to a Lumix GM1, and Nikon 1 10mm f/2.8 mounted to a Nikon 1 V3 with a user optional EVF.

LensSigma 19mm f/2.8Lumix G 14mm f/2.5Nikon 1 10mm f/2.8
System crop factor1.522.7
Equivalent focal length29mm28mm27mm
Maximum aperturef/2.8f/2.5f/2.8
Equivalent max aperture, in terms of DoFf/4.2f/5f/7.6
Weight140g55g77g
Diameter61mm56mm56mm
Length46mm21mm22mm
Filter thread46mm46mm40.5mm
Minimum focus0.20m0.18m0.20m
Lens elements/groups8/66/56/5
Hood includedYesNoNo
Focus ringYesYesNo

The lenses are laid out here:


Sigma 19mm f/2.8


I have the first version of the lens, the "EX DN". It has a nice plastic finish, with a ribbed base, good for mounting the lens. Also, the focus ring is ribbed for a good grip. The second version of the lens is called simply "DN", and is part of their Art-line of lenses. It has a smooth metal finish on both the base of the lens and the focus ring, making it harder to grip it properly, in my opinion.

The Sigma lens is a generic lens, made to be used on a number of mirrorless systems. I have tested the Micro Four Thirds version of the lens, and found it to be not quite as good as the Lumix G 20mm f/1.7.

This is not a pancake lens, in fact, it is rather large. It is often liked for the good image quality and the low price point.

Sony also has a similar lens, the Sony 16mm f/2.8 pancake. However, it is often perceived as being somewhat dull optically.

Lumix G 14mm f/2.5


This lens was originally launched as the kit lens for the ultra compact Lumix GF3 camera. It is still the smallest Micro Four Thirds lens, excluding the body cap "toy" lenses.

As this lens has often been sold cheaply on Ebay, coming from split GF3 kits, the perceived value of the lens has been small from time to time. However, I think this is a good lens, for the compact size. I made a comparison with the Lumix G 20mm pancake here.

In the picture above, I'm using a 46mm to 37mm step down ring as a simple hood.

Nikon 1 10mm f/2.8


This lens is different from the others in the sense that it doesn't have a focus ring. There is a ribbed ring around the front of the lens, but it is only for mounting the lens more easily. To be honest, I don't dislike this solution. I seldom use manual focus anyway, and the ribbed edge is great for getting a safe grip on the lens when handling it.

In the picture above, I'm using a 40.5mm to 37mm step down ring as a simple hood.

Here is a comparison picture of the rear side of the lenses:


The Sigma lens has an exit pupil which is recessed into the lens. This may look strange, but I am guessing it is for compatibility with the Samsung NX system, which has a much longer register distance than the Sony E-mount. So probably, the lens was designed to work with Samsung NX, even if they haven't launched a lens for Samsung NX yet.

The Nikon lens has the smallest exit pupil, by far. A large exit pupil is often seen as a mark of quality. We shall see if this matters in the comparisons in this article.

Sharpness


To evaluate the image quality, I have taken a series of images with all three lenses at various apertures. All the images were taken on a tripod, at base ISO, and with a shutter delay to avoid camera shake.


All the lenses do very well in the image centre, even wide open. So I don't see much point in going into details there.

To better find the differences between the lenses, I am looking a the performance in the top left corner, which tends to be more challenging to render for a lens.

Looking at 100% crops makes it easier to compare the image quality (click for a larger image):


What we see here, is that the Lumix G 14mm f/2.5 has a very good performance in the corner, even wide open.

The Nikon 10mm lens improves when stopping down, and achieves a very respectable performance at f/5.6.

The Sigma lens is the least good of the three, and is more dull even at f/5.6. This is consistent with my test of the Micro Four Thirds version of the lens, in which it did not impress.

Bokeh


In the top table, I quote the "equivalent max aperture, in terms of depth of focus". This is the max aperture multiplied with the crop factor. The smaller the number, the more selective focus the lens/camera system is capable of.

As the Sony system has the largest sensor of the three formats, the Sigma lens, when used on a Sony E-mount camera, can take pictures with the most selective focus. This means that the background can be the most blurred when you are using the largest aperture.

Here is an overview of the relative sensor sizes (from Wikipedia):


The Sony camera uses the APS-C sensor size, and the Lumix camera uses the Four Thirds size. Finally, the Nikon 1 camera uses the 1'' sensor size.

Here is a series of images, taken with a similar focus distance of about 0.3m, which illustrates the differences in depth of focus and bokeh:


Looking at 100% crops, we see that it is in fact the Nikon lens which has the nicest looking bokeh, even if it has the least selective focus.


And another example taken in daylight with the same short focus distance (click to enlarge):


From the 100% crops, we see clearly that the Sony lens is the most capable of achieving a blurred background:


The conclusion here is that if bokeh is important for you, then the Nikon 1 system may not be your system. If you want to achieve the most selective focus, then go for a large sensor system, like the full frame Sony A7.

From my point of view, I think the smaller sensor of the Nikon 1 system makes good sense. I get more depth of focus, which is, in my use, often a good thing.

Geometric distortion correction


Most mirrorless lenses feature some in camera distortion correction. To examine the geometric distortion characteristics, I have photographed a square tiled wall, and then overlaid the out of camera JPEG (in black) with the uncorrected image (in red). I used the third party RAW converter software UFraw to assess the uncorrected image.

Sigma 19mm f/2.8 (0%)Lumix G 14mm f/2.5 (-16%)Nikon 1 10mm f/2.8 (-4%)

The percentage in brackets is the relative distortion correction applied in The Gimp image processing software to get a rectilinear image. This is a way to compare the relative distortion between the lenses.

The Sigma 19mm f/2.8 does not use any in-camera distortion correction at all. However, it is not completely rectilinear, and you can see some barrel distortion.

The Lumix G 14mm f/2.5 requires the most in-camera distortion correction of the lenses. And at a short focus distance, you often get some residual barrel distortion. At infinity focus, this is not an issue.

Last, the Nikon 1 10mm f/2.8 needs some minor geometric distortion correction. However, after the adjustment, I find that the images are very nicely rectilinear, the most of the three lenses.

Conclusion


It is perhaps odd to compare these lenses, as they are for different systems, and very few will choose between them. But my conclusion is, again, that the Lumix G 14mm f/2.5 is a very under appreciated lens. It is generally seen as a "cheap and sub par" lens, but in my comparisons, it often comes out like a star performer. I like the lens a lot for the consistently good image quality, the fast autofocus, and the very small size.

The Sigma lens does not get good scores here. It has the least sharpness, and is the largest of the three. On the other hand, it is also the cheapest.

The Nikon lens performs very respectably. I think it has the best out of focus rendering of highlights (night time), and the sharpness is quite good. It is small, and focuses quickly. It also appears to have the least vignetting when wide open.

Friday, 8 August 2014

From the competition

Here is a summary of my take on the Micro Four Thirds competition.

Nikon 1


Nikon were quite late to the mirrorless party, with their Nikon 1 series. They took the rather bold step to use a fairly small sensor, the so called "1 inch sensor". Don't be fooled by the name. Just as the Four Thirds sensor is less than 4/3'' diagonally, the 1 inch sensor is less than 1'' diagonally.

This odd naming convention comes from the time when radio tubes were used for sensors: A 1'' sensor would be an radio tube with a 1'' diameter, while the actual imaging area would of course be much smaller than 1 inch.

Some speculate that Nikon chose to use a smaller sensor to protect their popular DSLR line. I think it was more due to a genuine desire to make the camera system small, which also differentiates it more from the DSLR cameras.



From the start, the Nikon 1 system left the market puzzled: Who is it for? Who would buy toy coloured camera kits with a poor ergonomy and a high price? To add to the confusion, Nikon did release high end lenses, like the Nikkor 32mm f/1.2 portrait lens. But with no enthusiast friendly camera layout, who would use them?

As it turns out, the Nikon 1 system has three strengths, in my opinion:

  1. Very good implementation of PDAF from the start. When I tested the first generation entry model Nikon 1 J1, I found that it had vastly better autofocus performance than the later and premium priced Lumix GM1.

    The PDAF technology implemented means that you get very good autofocus performance during video recording, and, probably more essentially, for moving subjects in AF-C mode. The Nikon 1 cameras can rival high end DSLRs in this area. This autofocus performance is the most important when using long lenses.

  2. Very fast framerates. The Nikon 1 cameras can take 60 frames per second in full resolution mode, and while saving the full RAW image. Of course, this only works in electronic shutter mode, but unlike the Panasonic Micro Four Thirds cameras, the E-shutter has a fast enough readout to avoid the rolling shutter issues.

    This makes the Nikon 1 cameras well suited for sports, for example, where you may want to take a 20 frame burst during a crucial moment, and then later pick the one you want to publish.

  3. The Nikkor CX 70-300mm f/4.5-5.6 (my review) long tele zoom lens. With an impressive 810mm equivalent focal length, this is the smallest birder-friendly lens available currently.

    Combined with the very good PDAF AF-C performance, and the high frame rates possible, this lens makes the Nikon 1 system to a dream come true for anyone interested in photographing birds and wildlife, while wanting to keep the bulk of their gear down. The lens is also useful for spectator sports.

    There is also the Nikon 1 V3 camera, which adds "almost DSLR ergonomy" to the Nikon 1 system. Below it is seen to the left. with the new 70-300mm lens mounted, together with the Lumix GH4 and 100-300mm lens:



If you are not into any of these three areas, then I think you should not look further into the Nikon 1 system. There are other systems that are better suited, unless you are interested in the topics above.

Canon EOS M


Canon also have their mirrorless system. But so far, they only have a small handful of lenses available, and one first generation camera. The camera has very poor autofocus performance, and the ergonomy is sub optimal.

In the mean time, Canon have introduced the EOS 70D, with an innovative PDAF capable sensor. I was expecting that Canon would put this sensor in a mirrorless camera, which should solve their autofocus speed problems. However, this does not seem to happen yet.

With the lack of lenses, and the poor performance of the camera, I would say stay away from the Canon EOS M system.

Fujifilm X


Fujifilm have invested a lot in their mirrorless camera lineup, and they appear to be committed for the long run. They have a very clear niche: Enthusiasts who like the classic lineup of lenses, and retro styled cameras. The cameras and lenses are of a high quality. And even if they look old fashioned, they do employ recent innovations.




The Fujifilm system is for traditionalists who are not heavily into video.

Sony


While Fujifilm have been committed to one line of cameras, the opposite is true for Sony. They started off in the digital system camera with buying Minolta technology, and rebranding a lot of old lenses. Then they improved it with the SLT technology, to enhance the autofocus performance during live view and during video recording.

Just when everybody thought Sony had quit their SLT line of translucent mirror cameras, they remade their top line Sony SLT A77 with a SLT A77 II:



The camera looks and feels like the predecessor, but is updated in many ways: It gets the newest generation sensor, new image processor, and a better autofocus system.

And autofocus is just the key to understanding why this type of cameras exist: Even if the mirror is not used for the viewfinder, like other SLR cameras, it is still used for the traditional PDAF autofocus sensors. This allows the camera to use high precision PDAF autofocus during video recording, and for tracking moving objects. In this way, it is much better than mirrorless cameras, which are not good at tracking moving objects, or focusing during video recording.

However, this is still a transitional technology: Eventually mirrorless cameras will do this just as well, and the line of SLT cameras will disappear. Due to better image processing, a camera like the Lumix GH4 has taken a big leap in this area, and we can still expect further improvements.

Beyond innovations in DSLR cameras, Sony have also launched a mirrorless line of cameras. First, they made a line of NEX branded cameras with an APS-C sized sensor. The first generation were quite strange, but the cameras have since become more normal looking. In 2013, this line was rebranded, with the removal of the "NEX" name. The cameras are now just called "Alpha", like the other system cameras from Sony.

Some interpreted the removal of the "NEX" name as a discontinuation of the APS-C mirrorless cameras. But this is not true, Sony have since made the quite interesting Sony A6000. This camera is reasonably priced, and packs a lot of features. It is probably the first mirrorless camera from Sony which utilizes PDAF technology to provide a really useful autofocus for moving subjects.


The Sony A6000 comes in a kit with the Sony PZ 16-50mm f/3.5-5.6. I have tested the lens and compared it with the Lumix X PZ 14-42mm. My conclusion is that they are both so-so, with some quirks. So from the kit, I would say that the lens is probably the weakest link.

And the big news from Sony is of course the venture into full frame mirrorless with the Sony A7 cameras. They use the same E-mount as the previously NEX branded mirrorless cameras. However, to use the full sensor, you need the full frame capable FE branded lenses, e.g., Sony FE 35mm f/2.8 and Sony FE 55mm f/1.8.

There are three cameras to choose from: Sony A7 is the basic model, with 24MP. It uses PDAF technology for faster autofocus.

Sony A7R is a 34MP camera, with does not include PDAF. This is less of an action camera, and is more intended for those who prioritize a high resolution. It could be used by, e.g., landscape photographers.

Finally, Sony A7S is a camera with exceptionally high sensitivity, the ISO goes all the way up to 409.600. This is at the expense of the resolution, there which is only rated at 12MP. This camera can also record 4K video, but only with an external video recording unit connected to the HDMI output.

Sony is not as focused on one line as the other manufacturers. While they have a decent list of lenses for their APS-C mirrorless cameras, it is unclear if they will continue to enhance it, or proceed with full frame lenses for the top end of their portfolio.

This leaves the lower end users with a dilemma: Should they invest in an APS-C sensor camera, not knowing if Sony will continue to develop interesting lenses for it? As I see it now, Sony is mostly interesting for those who want to have a full frame camera.

Samsung NX and Mini NX


Samsung were early entrants into the mirrorless market, with their NX line of cameras back in 2010. However, the design has one flaw: The flange focal distance (register distance) is too long, at 25.5mm, just barely shorter than the classic Leica M system.

The long register distance means that the cameras need to be larger, but that is not all. It also means that the lenses, especially the wide angle lenses, have to be larger. A short register distance makes wide angle lens design easier, they don't need a large retrofocal design. With a long register distance, you don't get this advantage.

Samsung were quite good at launching a lot of lenses quickly. However, some of them were based on older DSLR optical designs, and were fairly large.

Samsung is now trying to fix all these problems by launching yet another mirrorless camera system, the Mini NX. It has a much shorter register distance. Also, the new camera system has a 1" sensor, like the ones in the Nikon 1 cameras and the Sony RX100 III. This sensor has a size which is about 1/3 of the APS-C sensor sitting in their first NX system.

The first camera out is the Samsung NX mini, and two lenses: 9mm f/3.5 pancake (corresponding to a 24mm wide angle lens), and the 9-27mm f/3.5-5.6 collapsible standard zoom lens.


The camera is styled in the now trendy smooth style, without any grip on the front. Even with the flip up LCD screen, it is still the thinnest and lightest interchangeable lens mirrorless system available.

These cameras look like they will be popular with fashion conscious South Korean people. But they don't appear very ergonomic in daily use. I do like the compact and wide pancake prime, though. Such a compact 24mm equivalent prime would be good to have also in Micro Four Thirds. The closest we come now is the Lumix G 12-32mm f/3.5-5.6 (my review).

Conclusion


Looking back in time, it is now around ten years ago that digital system cameras became fairly common. Cameras like the Canon EOS 300D (Digital Rebel, 2003), and the Nikon D70 (2004) made this possible, by offering affordable and well performing system cameras to a wider audience. Further, the cameras could use existing lenses from earlier film based cameras, that many already had lying around.

What followed was a period when having a large size camera was trendy. A large camera looked professional, and that was a look often favoured by the consumers. Around the same time, we got the "thin DoF craze", where it became trendy to use large aperture lenses, e.g., relatively inexpensive 50mm f/1.4 normals lenses, for a very selective focus effect.

Times are changing now, and we are seeing more and more that camera news is all about size: Small sized quality cameras has become trendy.

With the vast Micro Four Thirds lens lineup, I think that the M4/3 system still has a strong position in the market.

But the Nikon 1 system is interesting for those into sports, birds and wildlife, while the Fujifilm X is a good choice for those who like retro styled cameras, and classic prime lens layouts.

Sony have jump started the full frame era for mirrorless cameras with the Sony A7 cameras. However, again the lenses become fairly large, negating the advantage of mirrorless in the first place.

Ten years back, DSLRs were basically quite similar. Most used an APS-C sized sensor, they relied on legacy lens mounts, and had the same features. It is fascinating to see the diversity now: Large differences in sensor sizes, register distances, features and looks.

Sensor sizes


Here is an overview of the relative sensor sizes (from Wikipedia):


Sony A7 uses the "35mm full frame", while the other Sony mirrorless cameras, e.g., Sony A6000 use APS-C.

Samsung is using both APS-C (NX mount) and 1'' (Mini NX). Micro Four Thirds uses the Four Thirds sensor size, which is size wise between the APS-C and 1'' sensor sizes. Finally, the rather odd Pentax Q cameras use the 1/1.7'' sensor size, but the first generation used the even smaller 1/2.3'' sensor.

Sunday, 3 August 2014

Pancake zoom lenses compared

Panasonic announced the Lumix X PZ 14-42mm pancake zoom lens (my review) in 2011. Since this time, an collapsible pancake zoom has become a must have kit lens for most mirrorless systems. I have previously compared it with the Sony 16-50mm pancake zoom lens, and this time, I am comparing it with some similar lenses from Nikon.

Below, I have the four lenses laid out:


From left to right: Lumix G 12-32mm (my review), Lumix X PZ 14-42mm (my review), Nikkor 11-27.5mm, and Nikkor 10-30mm PD

On the Lumix lenses, I have used a 37mm filter ring as a simple protection against getting fingerprints on the front lens glass elements. To make them, I got cheap 37mm filters, and removed the glass.

Specifications


LensLumix G 12-32mm (my review)Lumix X PZ 14-42mm (my review)Nikkor 11-27.5mmNikkor 10-30mm PD
Aperture rangef/3.5-5.6f/3.5-5.6f/3.5-5.6f/3.5-5.6
Lens elements/groups8/79/88/69/7
Diameter56mm61mm58mm58mm
Length25mm27mm31mm28mm
Weight70g95g83g85g
Filter thread37mm37mm40.5mmNone
Hood suppliedNoNoNoNo
Optical image stabilizationYesYesNoYes
Manual focus on lens?NoneLever, 2 speedsNoneNone
Zoom operationManualPower, lever, 2 speedsManualPower, ring by wire


All the lenses share the same aperture range, f/3.5-5.6. However, it is important to understand that there are still different ways in which the maximum aperture changes through the focal length range. Here is a chart showing the equivalent focal length of the lenses (relating to the old 135 film format), and the respective maximum apertue for each lens:


There are many things to comment from this. We could argue that the Lumix lenses "cheat" in their specifications, as their maximum aperture more quickly goes to f/5.6. The difference between the Lumix X PZ 14-42mm and the Nikkor 10-30mm PD is about 1/2 stop at 60mm equivalent, which is a significant effect.

Also, we see that if you are interested in wide angle, the Lumix G 12-32mm may be the best choice, as it goes all the way down to 24mm (equivalent). Also, the Nikkor 11-27.5mm has the least interesting focal length range, starting at 30mm equivalent. Then again, it is designed to be a cheap and light lens, for use in the least expensive camera kits.

In use


Here is a video showing the startup sequence for the two motorized lenses:



As you see, the Lumix X PZ 14-42mm extends quicker than the Nikkor 10-30mm PD: Both are probably sufficiently fast, though.

The Lumix G 12-32mm is extended and collapsed by rotating the zoom ring:


This operation feels quite smooth, and the lens is rather rigid when extended. Some looseness of the extended front lens element can be felt in the extended position. This lens has an aluminium exterior, however, it is just a thin layer which is glued to a plastic mechanism and chassis. So while this lens has the most metal on the outside, it is still the lightest of the four lenses.

I think the ergonomy of the Lumix G 12-32mm is less than optimal. It has a nicely grooved zoom ring, but there is little to hold on to when mounting the lens. Why not have some ribbed surface at the base of the lens? That would have made the handling better.

Finally, the Nikkor 11-27.5mm operates like the Lumix 12-32mm lens. You twist the zoom ring to extend it, which also powers on the camera, a nice touch. This lens has a cheaper feel to it, with the zoom ring being less dampened. But it operates quite ok. The zoom ring is nicely rubberized, which I do like.

All of these lenses autofocus very quickly. For non-moving subjects, you are not going to find the AF speed problematic at all. For moving subjects, the PDAF technology employed by Nikon is generally superior, and the Nikon 1 system is the way to go for the best AF-C performace.

Image quality


To test the image quality, I have photographed the same scene with all the lenses, at different apertures. I used the Lumix GH4 and Nikon 1 V3 cameras, respectively. They were set to the base ISO, and I used a tripod.

Wide angle


Here are the pictures:

Lumix G 12-32mm @ 16mm f/3.9Lumix X PZ 14-42mm @ 15mm f/3.9
Nikkor 11-27.5mm @ 11mm f/3.5Nikkor 10-30mm PD @ 11.2mm f/3.8

To better compare the image quality, here are some 100% crops at various apertures. From the right centre area:


From the top, right corner area:


And from the top area:


From the long tele end


Here is a similar test for the tele range of the lenses.

Lumix G 12-32mm @ 32mm f/5.6Lumix X PZ 14-42mm @ 32mm f/5.6
Nikkor 11-27.5mm @ 24.1mm f/5.6Nikkor 10-30mm PD @ 23.1mm f/5.6

And 100% crops from the centre:


And from the lower left corner:


Analysis


I was a bit surprised when seeing these results. I had expected more differences, but the example images are in fact rather similar. From Panasonic, I notice that the Lumix G 12-32mm is clearly best in the tele end, while they are more closer at wide end. The Lumix X PZ 14-42mm does well in the wide end, but the 12-32mm lens is probably still slightly better even here.

From my previous experience, I generally find the Lumix G 12-32mm to perform the best out of the two Lumix lenses.

From Nikon, I think the Nikkor 11-27.5mm is slightly better. But the difference is small.

Comparing between the brands, it seems like the Nikon lenses generally do better than the Lumix lenses.

There is little Chromatic Aberration (CA) problems here. In high contrast areas, we probably see some small effects mainly from the Lumix lenses, but I wouldn't worry about them.

Geometric distortion


Most Micro Four Thirds lenses feature some in camera distortion correction. And these lenses, with the wide zoom range, are no exception. To examine the geometric distortion characteristics, I have photographed a square tiled wall, and then overlaid the out of camera JPEG (in black) with the uncorrected image (in red). I used the third party RAW converter software UFraw to assess the uncorrected image.

Lumix G 12-32mm f/3.5-5.6 at 12mm (-18%)Lumix X PZ 14-42mm at 14mm (-15%)
Nikkor 11-27.5mm at 11mm (-11%)Nikkor 10-30mm PD at 10mm (-9%)

The percentage in brackets is the relative distortion correction applied in The Gimp image processing software to get a rectilinear image. This is a way to compare the relative distortion between the lenses.

At 12mm and 14mm, you see that both the Lumix lenses still feature some barrel distortion, even after the in-camera image processing. This is not uncommon at short focus distances with wide angle lenses that feature internal focusing. The same can be seen also with the Lumix G 14mm f/2.5 at short focus distances.

The Nikon lenses, though, appear to avoid this problem. The Nikon lenses also have much less geometric distortion in the first place, and appear to rely more on optically correcting for the distortion.

A strange oddity with the Nikon system, though, is that the images are not corrected for geometric distortion in the viewfinder. So you are seeing the distorted images while composing the images, while the final image is going to be corrected. This is very strange, and surely makes it harder to get the right composition.

Here is an example, using the newest Nikon 1 V3 camera with the Nikkor 11-27.5mm at 11mm:

Seen through the viewfinder
The output image

Bokeh


Bokeh is the nature of the out of focus rendering. You may think that to look at bokeh for these lenses is a waste of time: With the small maximum aperture, most of the scene is in focus anyway, so why bother?

However, in the longer end of the zoom scale, you can still get the background out of focus by photographing close objects. Here are some example images:

Lumix G 12-32mm f/3.5-5.6 at 32mm f/5.6Lumix X PZ 14-42mm at 42mm f/5.6
Nikkor 11-27.5mm at 27.5mm f/5.6Nikkor 10-30mm PD at 30mm f/5.6

Here are 100% crops to better evaluate the bokeh:


In these examples, we see that the Lumix X PZ 14-42mm shows some ringing, which looks distracting.

In terms of bokeh, the Lumix G 12-32mm f/3.5-5.6 and Nikkor 10-30mm PD produce the best results.

Focus noise


There is one area where Panasonic surely has the upper hand: Focus noise. The Nikon lenses have a lot more noise during focus operation. It's not likely to be a major problem, but when comparing them head to head, it is clear that the Lumix lenses are much more silent.

Zooming during video


Two of the lenses are motorized, and there is the possibility to use the motor zoom during video recording. This works very well with the Lumix X PZ 14-42mm, which has a lever operated motor zoom. It has two speeds, making it easy to zoom smoothly while recording. The focus normally keeps up quite well.

Not so with the Nikkor 10-30mm PD, though. It also has a motorized zoom. But it is hard to zoom smoothly when rotating the zoom ring. The zoom appears to stop at some fairly widely distanced stops, making it quite jerky. The focus appears to keep up reasonably well while zooming for both lenses.

Here is a comparison which shows that the Lumix lens is by far superior. I used the Lumix GH4 and Nikon 1 V3 cameras.

Both videos were recorded at 60 FPS, 1080p.



In the video, the zooming starts at 0:05s and 0:20s.

Conclusion


While these lenses share a lot of characteristics, they are still very different.

First of all, if you are going to be using video a lot, then you should consider to go for Panasonic rather than Nikon. The Lumix lenses and cameras are just much better suited for video use.

If you would like to use the widest angles, then go for the Lumix G 12-32mm, which starts at 24mm equivalent, which can be fun and useful.

In terms of image quality, it appears to me that the Nikon lenses are consistently best.

As the Nikkor 11-27.5mm doesn't feature optical image stabilization, it may be sub optimal for use other outside during daytime. Also, video use can be a challenge without image stabilization.

As long as you don't plan to zoom during video recording, the Nikkor 10-30mm PD is probably one of the better lenses. It does have quite some operation noise, though, both during zooming and when focusing.

Most of the time, I use the Lumix G 12-32mm. Because it is very compact, has a good wide angle, and consistently gives very sharp images. Also, it has image stabilization, useful for video recording. It is a good, compact, all around lens.

Pros:
Very wide angle
Very light
Pros:
Two speed power zoom, good for video
Pros:
Consistent good image quality
Cheap
Pros:
Consistent good image quality
Automatic lens cap
Cons:
Poor ergonomy
Short in the tele end
Cons:
Not the best image quality
Cons:
No image stabilization
Noisy
Cons:
Jerky zoom operation
Noisy
No filter threads