Panasonic LX7 topic

trevmar

zcream, where are you seeing that jack? I don't see it in my documentation?

UPS hasn't delivered the camera yet, but it is "out for delivery" allegedly...

zcream

I bought one too. what the heck! It does have exposure compensation. I can try to control the light, and make sure that I get the right shutter using exp comp.

[AV OUT/DIGITAL] socket

Hoping that this will accept a remote as well though the manual does not mention it.

trevmar

OK, my LX7 arrived, and I popped in a spare (charged) battery. These are my initial impressions with 720p and 1080p video. Before I did anything, I set my PhotoStyle (Film settings) to Custom -- Contrast -2, Sharpness -1, Color 0, NR -2. I like tone grading to start off pretty evenly. I also set iDynamic to High and iZoom to ON (will test it OFF later, ON is the setting I use on the LX5).

I set it to Creative Video, Full Manual. The LX7 passed my first test - it allowed a 1/30 shutter as well as 40, 50, 60 80, 100 120 etc. Hmmm, max iZoom is 7.5x on 1080p. Aperture has to be adjusted on the ring, with lots of clicks -- will look at this again later.

The bokeh on video, even on wide, gives significant focus hunting. This is exaggerated as the resolution looks excellent (I will shoot a chart later). Oooh, bokeh is going to be an interesting beast to manage, especially at full reach.

ISO 3200 give video noise, nothing that DNR in Virtualdub or Vegas won't get rid of. But I would probably want to stick to ISO800. Remember the LX5 had CCD pixel binning in Creative Video , which worked well to ISO3200, so the LX5 will always be more sensitive than the newer CMOS sensors.

Tone grading is excellent. As good as I have seen, marginally more detail than my LX5 in shadow at ISO800. White balance not as good as v2 software for LX5, but manageable.

So - initial impressions are - this is an amazing beast. If only -- if only -- if only it wasn't crippled to 30 minute clips in 1080p. It seems to record 4+hrs on 720p (with a 32GB SDHC card). Why, oh why, did Panny do this to me???

trevmar

here is the output of the MediaInfo program with a short test clip: Format : BDAV, Format/Info : Blu-ray Video, File size : 206 MiB, Duration : 1mn 1s, Overall bit rate : 28.3 Mbps, Maximum Overall bit rate : 28.0 Mbps,

Video: ID : 4113 (0x1011), Menu ID : 1 (0x1), Format : AVC, Format/Info : Advanced Video Codec, Format profile : High@L4.2, Format settings, CABAC : Yes, Format settings, ReFrames : 2 frames, Duration : 1mn 1s, Bit rate : 27.0 Mbps, Width : 1 920 pixels, Height : 1 080 pixels, Display aspect ratio : 16:9, Frame rate : 59.940 fps, Resolution : 24 bits, Colorimetry : 4:2:0, Scan type : Progressive, Bits/(Pixel*Frame) : 0.217, Stream size : 196 MiB (95%),

Audio: ID : 4352 (0x1100), Menu ID : 1 (0x1), Format : AC-3, Format/Info : Audio Coding 3, Duration : 1mn 1s, Bit rate mode : Constant, Bit rate : 192 Kbps, Channel(s) : 2 channels, Channel positions : L R, Sampling rate : 48.0 KHz, Stream size : 1.40 MiB (1%),

Text: ID : 4608 (0x1200), Menu ID : 1 (0x1), Format : PGS, Duration : 1mn 0s,

trevmar

Attached is the analysis of that quick clip with GH Stream Parser 2.7

zcream

@trevmar Would you consider putting it into HS mode and seeing if you can still lock shutter and aperture ?

trevmar

The only setting it allows is EV, sorry. I can't even zoom while it is shooting. "PhotoStyle" (Film settings) are the only other configurable option. The timer says 7mins 29secs available at 120fps.

Vitaliy_Kiselev

Considering 120fps, it is not "features locking" I suppose.
LSI just can't keep up if you allow this adjustments.

zcream

@Vitaliy_Kiselev I can understand not being able to zoom. But locking shutter and aperture is a simple matter. EV also locks shutter and aperture, the only difference being that we cannot control what its locked to. Stupid stupid Panny!

zcream

@trevmar Does the LX7 allow you to switch between NTSC and PAL ? Just want to check if I need a NTSC model for 120fps. PAL only gives 100fps

trevmar

@zcream No, I don't see any setting for PAL, nor did the shutter go below 1/30 second on Creative Video. Additionally, the EU versions are crippled so that 720p is also limited to 30 minutes. I am sure they are selling multiple configurations, as the box is clearly marked: "NTSC"

trevmar

Just doing some quick testing here, I shot a 2hr 4min 720p video with a 1/30 shutter before the battery ran out. Interesting that the output bit rate was 7819Kbps compared to 18Mbps the nominal rate. That is 0.142 bits/pixel*frame, much less than the LX5 was giving (avg 0.569). The LX5 does not have B-frames, and they clearly have totally different AVCHD encoders. Subjectively the LX7 looks clean and crisp. It might have been bokeh reducing background clutter and VBR bit-rate, I am not sure.

After indexing the MTS file with DGindex I examined it frame by frame with AVIsynth and Virtualdub. Each of the 1/30 sec shutter images is placed in two adjacent, identical 60p frames within the AVCHD file. Motion blur looks pretty good, but I have to test that on a better subject...

zcream

Is there a way to check the shutter (perhaps via half-press) when using EV lock ?

trevmar

EV lock? When you set the EV it doesn't affect focus. Are you thinking of AF lock? Once you activate AF lock the camera will not focus again until you release it.

trevmar

I have had a closer look at the LX7 with 720p/60 AVCHD vs LX5 with 720p/30, both with 1/30 shutter. Filming the same, largely static, indoor scene the LX5 used 0.545 bits/pixel*frame (vs 0.142 on the LX7). Vastly improved compression in the LX7. The LX5 ran for 2hrs 16 mins before the battery was exhausted, the identical battery in the LX7 ran for 2hrs 4 mins. Image clarity is better in the LX7. These are first impressions, but the LX7 does give a cleaner image (at ISO800) than the LX5, and improved tonal grading (contrast= -2, iDynamic=High). If only Panasonic had not crippled the FullHD (which is even cleaner). I can't avoid the need to record long sessions, much longer than 30 minutes... Guess they will have to be in 720p... Sigh...

trevmar

trevmar

I just ran a series of AVCHD videos with a nearly black image (int ND8+ext ND8) and could not observe any "preferred ISO" levels such as are seen on the GH2 noise profile. The sensor is well-behaved from ISO 400 to ISO 2500.

zcream

@trevmar I was referring to the shutter speed not focus. Light changes in a EV lock will require adjustments of ISO or/and shutter to keep EV constant. I just want to see how tolerant the algorithm is to light changes. I may be able to lock the EV when the shutter is at 1/400 or 1/800 - but I have see if it changes ISO or shutter first in case of light changes...

trevmar

I always use 'shutter preferred' mode when taking video. Usually with 1/30 for 30fps. I adjust the ISO (fixed) and ND8 (if necessary). The camera adjusts aperture to expose the movie images. Is that what you mean by 'locking EV'?

trevmar

Here is the central portion of the standard test chart for the 1080p video at f4, ISO 100, and 1/200 shutter. You can find a comparative test chart for the GH2 and Canon 7D at: http://www.slashcam.de/artikel/Test/Panasonic-GH2---der-kompakte-Ueberflieger--alles-.html

https://www.dropbox.com/s/hv0h8ax1mw97sxf/Chart_cropped.jpg

Conclusion: Video is not as good as the GH2 (what was I expecting?). Not much worse than the Canon 7D however (LOL)

zcream

@trevmar Using the HS video mode, would you consider locking shutter at 1/240 (or 1/200 in PAL-land) and locking EV. Then filming indoor under fluoro lighting ? Im curious to see if shutter preferred mode works under HS mode..

trevmar

How do I "lock EV"? Is there menu item for that?

Vitaliy_Kiselev

Review - http://www.trustedreviews.com/panasonic-lumix-lx7_Digital-Camera_review

trevmar

I have been looking into the Moire from the LX7. It is excessive, IMO. But I am not an expert, so I am posting my observations here to ask for your opinions. First, I noticed bad quantization in a frame from a 1080/60p video (first attachment below). This was taken with a film setting of -2 for sharpening, -2 for noise reduction and no internal i.Resolution or i.Zoom (etc).

So I took a closer look at the car which exhibited the worst artifacts: (second attachment below)

The steps on the front window-pillar-chrome-strip are 2 pixels apart vertically and 3 pixels apart horizontally. The rest of the roof is also squeezed into a matrix which is certainly not a 1x1 pixel matrix. This would account for the terrible moire seen on a 1080p ISO chart frameshot (3rd attachment below).

I have been looking at a lot of video this past week from my LX7, and of downloads of FZ200 MTS files too. What I am seeing is that the FZ200 seems to have less absolute resolution than the FZ150 video, on average. The LX7 is better than the LX5 video, which was pretty bad. Yet when I shoot the ISO chart in 720p I don't get much practical difference from the 1080p resolution (4th attachment below)

Has anybody any insight or suggestions as to how to get best resolution from the LX7? Should I be pre-sharpening more (as post-prod sharpening exacerbates these artifacts)?

trevmar

As a point of comparison, the camera in my Samsung Galaxy Note cellphone produces a much better image from my 1080p ISO Test Chart. Similar data rates, also AVC High@L4.0, about 30Mbps - but much cleaner (see attached x1 file)

Howdy, Stranger!

Categories

Tags in Topic

Top Posters