Which Lens for the X5

[Lesmess]

Hi,

I can't decide on either the Oly 12mm F2 or the Pana 15mm F1.7. I can get the Pana at £150 cheaper than the Oly. I use the platform mainly to take photos, I already own an Oly E-M1 camera system. It probably makes sense to get the Oly for system matching, however the Pano gets some good write up's and is £150 cheaper.

Cheers Les

 

[Quadpilot]

Depends on the focal length you want to work with: 24mm or 30mm (35mm equivalent). The Oly has a lot of enthusiastic users. Just remember that for DCI 4K video, the crop factor increases to 2.3 from 2.0, making the Oly a 28 mm effective FL and the Pana 35mm.

 

[Sunscreen]

I own the Olympus 12mm f2 & it's a wonderful lens on the GH4. Can't comment on the Panny 15mm though. I'm excited to try out the 12mm on the X5R when it's eventually released. I'm optimistic that DJI will create a weight profile for the Panny 20mm f1.7 & the Olympus 45mm f1.8 sometime in the future.

 

[Lesmess]

Thanks folks for your replies, Oly 12mm F2 it is then.
Cheers

Les

 

[InterMurph]

Just remember that for DCI 4K video, the crop factor increases to 2.3 from 2.0, making the Oly a 28 mm effective FL and the Pana 35mm.

This is true for the Panasonic GH4; I haven't heard any details on how the X5 will handle this. Here is a helpful graphic explaining what the GH4 does:



The entire image , including the black bars on the top and bottom, represents the entire sensor. It is 3:2, 4608 x 3486 pixels. The GH4 uses the entire sensor for still photos.

Next in is the purple area; this is the portion of the sensor used for 1080p mode. It simply omits the top and bottom black areas in order to get the 16:9 aspect ratio. It ends up using 4608 x 2592 pixels, which it then "bins" down to 1920 x 1080.

Finally, the dark blue area is what it uses for 4K video. The GH4 actually supports two different 4K modes; the first is 4096 x 2160, or "cinema 4K" this is slightly wider than the 3840 x 2160 that we usually mean when we refer to "4K". This latter resolution (3840 x 2160) is simply four 1080p regions, maintaining the HD picture's 16:9 ratio.

The big benefit to these two 4K video modes: one pixel on the sensor maps to one pixel in the image. No pixel binning or combining is done. This gives the highest image quality possible on a given sensor. It also explains why, on a GH4, recording 4K footage and using your editor to down-size to 1080p produces better video than does recording 1080p footage. The former converts a 2x2 pixel array into a single video pixel, while the latter combines using sub-pixels.

 

[Quadpilot]

This is true for the Panasonic GH4; I haven't heard any details on how the X5 will handle this. Here is a helpful graphic explaining what the GH4 does:



The entire image , including the black bars on the top and bottom, represents the entire sensor. It is 3:2, 4608 x 3486 pixels. The GH4 uses the entire sensor for still photos.

Next in is the purple area; this is the portion of the sensor used for 1080p mode. It simply omits the top and bottom black areas in order to get the 16:9 aspect ratio. It ends up using 4608 x 2592 pixels, which it then "bins" down to 1920 x 1080.

Finally, the dark blue area is what it uses for 4K video. The GH4 actually supports two different 4K modes; the first is 4096 x 2160, or "cinema 4K" this is slightly wider than the 3840 x 2160 that we usually mean when we refer to "4K". This latter resolution (3840 x 2160) is simply four 1080p regions, maintaining the HD picture's 16:9 ratio.

The big benefit to these two 4K video modes: one pixel on the sensor maps to one pixel in the image. No pixel binning or combining is done. This gives the highest image quality possible on a given sensor. It also explains why, on a GH4, recording 4K footage and using your editor to down-size to 1080p produces better video than does recording 1080p footage. The former converts a 2x2 pixel array into a single video pixel, while the latter combines using sub-pixels.

Great explanation, and thanks for pointing out the fact that "Cinema 4K" area result in a 2.2x crop factor, while "4K" results in a 2.3x crop factor.

On a related subject, I've often wondered if 1080p HD pixel binning results in the need for higher processing power (even for a lower resolution image), whereas the 4K or Cinema 4K pixel-to-pixel mapping means a more linear recording path but more compression crunching to fit into the max bit-rate of the processor. Anyone out there with the chops to answer that question?

Edit: Just one correction to your post: the entire sensor area appears to be a 4:3 ratio. Hence Micro Four Thirds. I know you know that, just mis-spoke, right?

 

[InterMurph]

There are two things at play here: 1) generating the pixels for a video frame, and 2) compressing those pixels.

When the GH4 is in 1080p mode, it clearly spends processor time on 1), because it has to convert The 4608x2592 sensor readout into a 1920x1080 image. This could probably be done in hardware pretty quickly, but still, it's an extra step. Then in step 2), it's compressing a 1920x1080 frame, which is relatively small.

When the GH4 is in 4K mode, 1) is just a matter of reading the pixels from the sensor; no further processing is needed. But then in 2), it has to compress a 2840x2160 image, which is four times the size of the 1080p image.

What I would like to see is a 1080p mode that uses only the pixels used in 4K mode. The pixel binning would be easy; each 2x2 pixel array gets averaged into one pixel. That would produce a better image, I think, than including a few extra pixels on the edges.

 

[Cyclops]

Going back to the original thread 'Which lens for X5' and now that the camera has been out for while I'm wondering what people think of the DJI 15mm lens vs Panasonic Lumix 15mm and alternatively whether the Olympus 12mm is a good choice.

I'm leaning towards the Olympus 12mm for the slightly wider view - anyone got positive feedback for this lens for the X5?

I'm equally interested in capturing 4k video as in acquiring 16MP stills.

 

[InterMurph]

I have the Olympus 12mm and the DJI 15mm. I prefer the Olympus 12mm for the wider view. I believe that it's a slightly better lens, but I'm not sure I could prove it.

 

[Cyclops]

I have the Olympus 12mm and the DJI 15mm. I prefer the Olympus 12mm for the wider view. I believe that it's a slightly better lens, but I'm not sure I could prove it.

Thanks for that feedback. Have you got a lens hood for the olympus lens? Or found any ND Filters?

The only lens hood I can find is made of metal which i would imagine will upset the gimbal balance.

 

[InterMurph]

I don't use a lens hood. I occasionally use no ND filter, but usually I use this B+W 3-stop ND filter. No gimbal problems either way.

The Olympus 17mm lens, on the other hand, makes the gimbal quite unhappy without an ND filter. The gimbal motors run and make a loud whining noise. When I put that same B+W filter on it, the gimbal is quiet and happy.

 

[Cyclops]

I don't use a lens hood. I occasionally use no ND filter, but usually I use this B+W 3-stop ND filter. No gimbal problems either way.

The Olympus 17mm lens, on the other hand, makes the gimbal quite unhappy without an ND filter. The gimbal motors run and make a loud whining noise. When I put that same B+W filter on it, the gimbal is quiet and happy.

Got to keep the gimbal happy!

I have noticed some very nice lens flare on some of the X5 shots posted on the web

 

[howard rockliffe]

IMO the wider view of the Oly is much preferable.

 

[Cyclops]

Well I now have the Olympus 12mm sitting on my desk next to the new X5 Gimbal, thanks to RCGeeks, and will sit down later today and workout how to fit the new vibration plate. No real rush as the weather is so bad but I'm really looking forward to trying out this new system and am fully prepared for quite a steep learning curve.

What surprises me about the Olympus lens is how well small it is and how built it is. Very nice weight with a big lump of glass.