My new Lumix 7-14mm f4 lens

Categories: GH5 camera 5 Comments


This completes my full range of lenses for my GH4 User Review, the 7-14mm f4 WA Zoom is a cracking wide angle zoom lens, a must for landscape and interiors.


I decided in a fit of madness to drive the 370 miles down to Norwich to the WEX showroom and buy the final lens in my GH4 collection.


The 7-14mm is indeed the superstar of wide angle zoom’s in 35mm terms it’s 14-28mm and at f4 constant aperture. WEX have a very impressive Lumix display apart from the lack of GH4s on display…hard to come by.


I have started my GH4 User review filming shots with one GH4 and producing PTC with my other GH4 at 1080 50p 200Mbps All Intra and it looks stunning…way beyond my 720 50p 50Mbps Canon C300.


One interesting fact I learned by mistake is that the GH4 with an internal L-Ion battery acts as a silent cutaway camera, in other words the camera functions as a video/photographic camera even with the YAGH attached but in video mode with no sound.

You need to power up the YAGH via the 4 pin power XLR to get all the sound functions.

At-14mm At-7mm

For all your video production needs in Scotland, get in touch with Small Video Company Ltd

The 4K Debate…”technical”

Categories: 4K filming 3 Comments


“4K is FOUR TIMES the resolution of High Definition!” …really???

I do wish people, some of whom should know better, would stop quoting the marketing hype by saying that 4K or rather QFHD (Quad Full HD: 3840×2160 pixels), is four times the resolution of Full HD (1920×1080 pixels) when clearly it is TWO times the resolution (on each axis) and therefore FOUR times the NUMBER of pixels (X x Y axis, image width x height) on the sensor.
Resolution, in my 40+ years experience, has always been a linear measurement of lpmm (lines per mm) or, more accurately, lppmm (line pairs per mm: you need one white & one black line to see the difference).
In the case of digital sensors, we’re talking about how many pixels (image sampling points) are potentially available on a given axis. I say ‘potentially’ as other factors such as AA filters on the sensors, image processing/codecs and the resolving power of the lenses in use may be the limiting factors, regarding actual achievable image resolution, rather than the sensors native pixel count.
Hence QFHD (16:9 3840×2160) with 3840 pixels image width is twice the (sensor) resolution of Full HD (16:9 1920×1080 pixels) with 1920 pixels image width …simple mathematics: 3840/1920 = 2.
4K or, rather, Cinema 4K (17:9 4096×2160 pixels) at 4096 image width might also be said to be 2.133333333~ times the image width resolution of Full HD (4096/1920) but still two times on the height axis (2160/1080).
Using Bob Miano’s received ‘logic’ we might also claim that Full HD with an image pixel count of 2,073,600 pixels (1920×1080) is 2.25 times the resolution of HD at 921,600 pixels (1280×720) …that’s not a claim I ever recall hearing and, of course, the actual figure should be that Full HD is 1.5 times the resolution of HD (1920/1280) …a 50% increase, not 125%.
As for “capturing in 4K will allow you to “zoom in” to the footage in post” …yes, up to a 2x crop (onto a Full HD timeline), any more than that and you’ll be looking at an image with LESS than Full HD resolution. Try going in by the implied 4x crop and you’ll be looking at a 960×540 pixel image …less than (PAL) SD!
I can understand the marketing boys at Panasonic, and others, shouting the “4K is 4 times the resolution of HD” nonsense but ‘professional’ users might be better off not to over hype the possibilities and risk disappointing their customers …well at least until we get ’8K’ cameras that CAN shoot at 4x Full HD (7680×4320 pixels)!…?
Personally, having been happily using the GH3 for over a year, I’m just looking forward to exploring the additional possibilities of what I’ll be able to do, in both QFHD and Full HD, when my (pre-ordered) GH4 turns up

For all your video production needs in Scotland, get in touch with Small Video Company Ltd

Peter Loughran talks about Crop Factors – THE TRUTH AT LAST!

Categories: GH5 camera No Comments


Peter Loughran “Having collected my GH4 body on Thursday 8th May (too impatient to wait another day for delivery so drove to collect it as soon as I heard it was at my supplier …my thanks to Paul and Martin at 3D Broadcast I set about running some tests to see exactly what had changed compared to my GH3.
One of the things I really wanted to clarify was exactly what the various crop factors really are as there have been many misleading figures and guesstimates bandied about online, suggesting figures for the ’4K’ formats of around 2.3 (Panasonics own literature and manual only mentions that “The angle of view of motion pictures in 4K is narrower than those of motion pictures in other sizes.” without actually specifying the precise figures).
I knew from previous experience with my GH3, and now confirmed as being exactly the same in the GH4 (including checking the crop factor information in the EXIF data), that the 16:9 FHD and HD (1080p/i and 720p) video formats are read from the full width of the sensor (4608 pixels) but read from a cropped sensor height of 2592 pixels to give the 16:9 frame format from the (4608×3456 pixel) 4:3 format sensor.
As the 4:3 sensor height must be cropped vertically to produce the 3:2 stills format and the 16:9 stills/video format there is obviously a reduction in the frame diagonal (which equals the required image circle) and hence a corresponding increase in the crop factor. There is also a 1:1 (square) stills image format available which maintains the full sensor height but crops off the sides.
Note that the older GH2 had an oversized ‘Multi Format’ sensor which allowed the horizontal pixel readout width to be increased as the vertical pixel readout height was reduced and thus give a constant diagonal and constant crop factor of 2.0
The GH3 and GH4 do not have that constant crop factor so ONLY THE FULL SENSOR 4:3 FORMAT HAS A CROP FACTOR OF 2.0 …all other formats crop into the sensor and thus have higher crop factors.
For the sake of clarity, here are the crop factors (relative to a Full Frame 35mm Still Format 3:2 36x24mm = diagonal of 43.27mm)) which apply to both the GH3 and GH4 when using the full sensor based crops:

4:3 (stills and video [VGA] using full sensor width and full sensor height) = 2.0
3:2 (stills using full sensor width and cropped sensor height) = 2.08
16:9 (stills and video [HD, FHD] using full sensor width and cropped sensor height) = 2.18
1:1 (stills using cropped sensor width and full sensor height) = 2.36

Figures are as calculated from sensor dimensions and format aspect ratios, and confirmed by examining EXIF data (using ExifTool 9.54) which shows a rounded ‘Scale Factor To 35mm Equivalent’ figure and also a more accurate (particularly when using longer lenses) ’35mm equivalent focal length’ from which the exact crop factor can be calculated.
For example: using the Panasonic 100-300mm lens at 300mm the EXIF data shows a rounded ‘Scale Factor’ of 2.0 (when using 4:3 image format) and 2.2 (when using 16:9 image format).
The ’35mm equivalent focal length’ figures shown in EXIF are 600.0mm and 653.0mm so dividing those by 300mm (actual lens figure) gives the more accurate crop factor figures of 2.0 and 2.18 respectively.

Unfortunately, examination of the GH4s EXIF data for 4K and C4K video shows that it does not include the ‘Scale Factor To 35mm Equivalent’ or ’35mm equivalent focal length’ information so I have had to resort to the ‘old school’ method of actually shooting a known scale in order to compare the actual captured images in both the full frame width stills/video and the cropped frame width video images produced in 4K and C4K.
My test subject was a 120cm builders spirit level which has a very clear mm scale along its edge. I set up the camera (locked down on a very substantial tripod) and by careful adjustment of distance and zoom (using the Panasonic 12-35mm f2.8 lens), shooting still frames and examining them enlarged on the cameras display to see exactly what was being captured, was able to frame the mm scale such that the horizontal frame width was capturing exactly 1,000mm.
(I was able to adjust the setup to an accuracy of less than 1mm on the scale so the subsequent calculations should be accurate to approximately 0.1%).
Subsequent video samples, including 4K and C4K crops, could then be compared and ‘measured’ by reading off how much of the 1,000mm scale could be seen in the image (the video clips produced were imported into my video editing program and full resolution frame-grabs exported for critical examination of exactly how much of the mm scale was captured).
Knowing those figures, and the aspect ratios of the different formats, then allowed me to calculate the crop factors of the 4K and C4K videos as compared to the known crop factor when using the full sensor width and thus the overall crop factors relative to the Full Frame 35mm Still Format (3:2 36x24mm = diagonal of 43.27mm) (Note: that’s a stills image format, not ’35mm’ or ‘Super 35mm’ movie formats).
Note: the 16:9 FHD/HD videos show exactly the same horizontal field of view as the still images so they are certainly downsampled from the full 4608 pixel sensor width.
I have used the (arbitrary) observed/implied captured mm dimensions for the different aspect ratio formats (16:9 4K/FHD/HD and 17.07:9 C4K) in order to simplify the calculations in this test. The same % crops could be applied to the actual sensor dimensions if the true sensor area framing sizes were required.


(Camera & lens locked off to show 1000mm scale as exactly filling the horizontal frame axis).

FHD 1920×1080 (16:9) & HD 1280×720 (16:9) Full Sensor Width = 1000mm = 100% of sensor width.

4K 3840×2160 (16:9) Cropped Sensor Width (showing 85mm to 918mm) = 833mm = 83.3% of sensor width

C4K 4096×2160 (17.07:9) Cropped Sensor Width (showing 57mm to 946mm) = 889mm = 88.9% of sensor width

(interestingly, the 4K and C4K pixel crops are not exactly in the horizontal centre of the sensor but fractionally displaced to the right; possibly to do with how the sensor readout electronics are routed?)

Crop Factor calculations:

FHD 16:9 Format (full sensor width) @ 1000×562.5mm = diagonal of 1147.35mm

4K (16:9) Format @ 833×468.56mm = diagonal of 955.74mm
Crop factor of 4K (16:9) as compared to FHD 16:9 (full sensor width) = 1147.35/955.74 = 1.20

C4K (17.07:9) Format @ 889×468.56mm = diagonal of 1004.92mm
Crop factor of C4k (17.07:9) as compared to FHD 16:9 (full sensor width) = 1147.35/1004.92 = 1.14

These crop factors ARE IN ADDITION TO the known (GH3 & GH4) 16:9 (full sensor width) crop factor of 2.18 as compared to Full Frame 35mm Still Format (3:2 36x24mm = diagonal of 43.27mm).

Crop factors as compared to Full Frame 35mm Still Format (3:2 36x24mm = diagonal of 43.27mm):

FHD 1920×1080 (16:9 Full Sensor Width) crop factor = 2.18 (as previously calculated and confirmed by EXIF data).

4K 3840×2160 (16:9 Cropped Sensor Width) crop factor = 2.18 x 1.2 = ~2.6 (test calculated: 2.616)

C4K 4096×2160 (17.07:9 Cropped Sensor Width) crop factor = 2.18 x 1.14 = ~2.5 (test calculated: 2.485)

These measured figures correspond exactly (allowing for slight measurement variables in this practical test) to my previously calculated figures which were based on the assumption that the GH4s 4K and C4K video modes are taking a 100% pixel-for-pixel crop from the sensor.
This is essentially the same method as is used in the ‘Extra Teleconverter’ modes, on the GH3 and GH4, when pixel-for-pixel crops are used to extract 1920×1080, 1280×720 and even 640×480 (VGA) video from the centre of the sensor …giving corresponding levels of magnification (hence the ‘Extra Teleconverter’ label) as compared to the same resolutions when downsampled from the full sensor area crops.
The calculated, and observed, 4K 16:9 crop factor of 1.2x (over and above the HD/FHD 16:9 full sensor width crop factor) ties in perfectly with Panasonics own stated ‘Extra Teleconverter’ crop factor of 2.4 for FHD 1920×1080.
The 4K 16:9 100% (pixel-for-pixel) crop has twice as many pixels in each axis (3840×2160) as the FHD 16:9 100% (pixel-for-pixel) crop of 1920×1080 pixels so the ‘Extra Teleconverter’ type crop factor is only half as much.

My observation so far is that the 4K and C4K videos are MUCH sharper, even when played back at FHD (1920×1080)(I don’t have a 4K display as yet), than is the cameras own FHD (at 50p at up to 100Mbps IBP and 200Mbps All-i) which is downsampled by a factor of 2.4 from the full sensor width pixel resolution (4608/1920 = 2.4).
The full resolution frame-grabs show very clearly that the FHD frames are not only softer but also contain much more aliasing and moire artifacts than the 4K (in this test the mm scale is effectively unreadable on the FHD video but every single mm can be easily read on the 4K samples …partly helped by the additional crop factor magnification, but even when viewing the full resolution frame-grabs at the same subject size the difference is very obvious).
I suspect that this is probably due to the somewhat awkward 2.4 factor downsampling of the (16:9) 4608×2592 sensor resolution to 1920×1080 and suggests that the in camera FHD video might be better quality if Panasonic had taken it from the same 3840×2160 area of the sensor as the 4K uses (thus giving an exact downsampling factor of 2x in each axis).
Of course, that would entail having a FHD crop factor of 2.6 (same as the 4K) so the ‘must have a bigger sensor & shallowest possible depth of field’ fanatics would be outraged…
As things stand it looks as if I’m going to want to shoot at 4K for the extra quality even when editing/displaying to FHD …if only the GH4s 4K was available at 50p! …now where’s my GH5!..? ;-)

For all your video production needs in Scotland, get in touch with Small Video Company Ltd

How to claim your free GH4 accessories UK only

Categories: GH5 camera No Comments


Many of you are asking how do you claim your free battery and battery grip for your new Panasonic GH4…follow these steps

1. Before you enter the Panasonic promotion web site you will need the following on file…


You will need to scan the end of your GH4 box where the bar code details are (I have taken out the last 4 digits of my serial number) and also scan your retailers receipt with the purchase details on it.


You can wait for 40 days for these free items so the sooner you reply the sooner you will be enjoying your battery and grip.

For all your video production needs in Scotland, get in touch with Small Video Company Ltd

Sound Output set to REC SOUND ONLY in YAGH mode

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With the YAGH connected you don’t get an option to switch from REC SOUND to the preferred LIVE SOUND this may be a bug.

I noticed an infinitesimal lag on the headphone output…nothing to worry about but this is caused by the Sound Output being set to REC SOUND in the menu…unfortunately it’s greyed out.

Taking it a stage further I thought it may have been chosen before the YAGH was in place so I took off the YAGH and hey presto it was set to LIVE SOUND…placing the YAGH back it defaults to REC SOUND.

I hope Panasonic can fix this as LIVE SOUND is the preferred default for many of us.

For all your video production needs in Scotland, get in touch with Small Video Company Ltd

Panasonic DMW-YAGH Arrives…plus new menu in GH4

Categories: GH5 camera, Sound 2 Comments


Finally after what seemed a long wait the kit is complete, the Panasonic DMW-YAGH has arrived, the review can begin.

YAGH-front YAGH-back

The YAGH is bolted direct onto the GH4 and feels very solid, today was a bad day for initial testing as my grand daughter took priority but I did manage to try out the Hawk Woods BPU power adapter.

YAGH-wider Pouch

The BPU 12v regulated Power adapter fits into a pouch that Velcro’s onto my belt, this was my whole intention to have a neat, light weight power solution.


I also just had time to put a gun mic into Ch1 XLR and it worked a dream, one thing that I did not know was that once you attach the YAGH you get access to a new menu in the GH4, page 2 (not seen) allows you to set the battery voltage level alarm.

For all your video production needs in Scotland, get in touch with Small Video Company Ltd

That 4K image is jaw dropping…Scott Rhea

Categories: 4K filming No Comments

A world-renowned film director Scott Rhea created a film titled “Dalia’s Dream” in 4K using Panasonic LUMIX GH4.
Scott says: “Shooting with the GH4 was nothing short amazing as the 4k image that the camera produces rivals that of cameras costing exponentially more. The size, weight, and functionality of this camera were extremely well engineered and both user friendly to photographers of all skill levels. I found the touch screen interactivity to be faster and more accessible than previous working conventions and the focus confirmation feature something that sets this camera apart from others. Variable frame rate options, low light capability, and stellar image quality make this camera an extreme value and has just taken first position in my camera bag.”


For all your video production needs in Scotland, get in touch with Small Video Company Ltd

Panasonic GH4 Review “In the making”

Categories: GH5 camera No Comments


Our Panasonic GH4 review will be a belter, not only footage from 3 GH4s filming a documentary with background GH4 footage but a host of lenses and kit from the Glidetrack 2014 smoothest slider on the planet to the full blown GH4 filming kit using the YAGH SDI-XLR adapter.

For all your video production needs in Scotland, get in touch with Small Video Company Ltd

The perfect GH4 Eyecup

Categories: GH5 camera 8 Comments


This is a story about my third drawer down, the one I keep my bits from other cameras, yesterday I had a eureka moment when for the first time I remembered where something was…the third drawer down.


In the drawer was an eyecup from a previous camera I suspect a Sony and this was a bigger version than the one that comes with the camera.

I unwrapped it from it’s yellow (Sony) plastic bag and firstly took off the GH4 eye cup to discover it fitted round the back of the original eyecup.


As if were meant I fed the rubber round the back of the GH4s and hey presto it fits like a glove. Are there any downsides…you can’t pull the LCD out without holding the bottom of the eyecup out the road but thats just a knack.

The eyecup will be invaluable in broad sunlight but the downside is repeating it with the same eyecup, its either from a Sony NX70 or a Sony FS100, they come with a normal eyecup but also give you this extendable larger eyecup.

Look on EBAY for spare large rubber eyecups they are about £15, I will try to find out where we can get this eyecup and how much it will be.

For all your video production needs in Scotland, get in touch with Small Video Company Ltd

Working with Wi-Fi and the Panasonic GH4

Categories: GH5 Wi-Fi 1 Comment



Wi-Fi in the Lumix GH4 is far superior to the one in the GH3, connecting is a breeze and its almost lag free.


Firstly you need to download Panasonic Image App from the Apple iStore (Android store) to your iPad, iPhone, Smartphone or Android.


Press the Fn1 button for about 4s till the WiFi LED turns blue.

When you turn on Wi-Fi open the Panasonic IMAGE APP and your iPad will give you 2 options for a password or QR code, the simplest way is to choose the QR code.


Point the iPad to the QR code on your GH4s LCD screen, you will have to put it almost 25mm away from the code then slowly pull back from the code till your iPad reads it.


Then come out of that and go into SETTINGS you will see this INSTALL PROFILE screen and press install.


Make sure you choose the GH4 from the CHOOSE A NETWORK settings then re-start Panasonics IMAGE APP


This is the screen you are presented with on your iPad from here you can set White Balance (WB), f stops and Shutter Speed (F/SS), Peaking OFF or ON, Touch Screen AF and record.


If you have one of the two power zoom lenses you can zoom in and out via iPad.


What a far better way to browse your pictures on the iPad via Wi-Fi not only that you can delete them as well.


Apart from viewing your pictures you can also play video footage a great way to impress your client.

The downsides to the tablet are don’t expect to use it on sunny days, small lag in the picture and you can lose the Wi-Fi signal.

Upsides are browsing both video and photographs, deleting media, zoom control via specific power zoom lenses, ability to use the camera in remote control like a wildlife situation and it’s cool to show clients your footage.

For all your video production needs in Scotland, get in touch with Small Video Company Ltd