The range of a Wi-Fi connected camera to a smart phone/tablet appears to be about 10 metres (30 feet). Whilst this may be adequate for most users sometimes you want to control the camera over greater distances. I had the idea to use and old router as a Wi-Fi-extender to allow these greater distances. The router I chose was an old D-Link which was mains powered through a 9v dc power adaptor. To allow this to be used away from the house I used a USB to 9v adaptor (from Amazon - it also supports 12volts at 2A) and a 8000mAh power bank.
You begin by connecting the camera to the router via the camera Wi-Fi menu selection By Network option.
When the list of Wi-Fi devices is shown, chose your router and enter the router password from the camera screen.
You can now open the Panasonic app on the smartphone/tablet and connect to the router to establish the connection to the camera.
The router will give an additional distance (100 feet) 30 metres so if the router is placed within the 10 metres of the camera the smartphone/tablet can be up to the 30 metres point giving 40 metres in total.
USB adaptor - Amazon UK http://amzn.to/2uoldv0
USB adaptor - Amazon USA http://amzn.to/2sVxfaV
Schematic for the working version of the AGC Defeat Unit
The final circuit turned out to be more simplistic than I had originally thought.
I assumed that the input would need to be a sine wave to prevent harmonic distortion if a square or triangular wave was used for the input to the camera. In testing I found that the camera would still perform well with a square wave input so I decide to try both an astable multi-vibrator pair of transistors running at 20 KHz and a NE555 timer IC.
In the end I decide to use the more stable 555 IC as the frequency remained solid even during the battery run down.
Here is the schematic for the project.
The timing is done by R2-C2 giving 20KHz. The output from pin 3 is attenuated by R1-R3 to 7-8millivolts at the camera input after being coupled with the mic input and allowing for its impedance.
the right hand mic input goes straight to the camera input whilst the left hand input has the 20KHz signal injected into it.
If you wanted to get finer control of the AGC defeat voltage input R3 could be substituted with a 27K resistor and a 100K potentiometer in parallel with it. The output would be taken to C3 form the wiper of the pot. This would allow the output to be set for 0V to about 10millivolts.
The unit is powered by a PP3 9v battery.
Here is the built unit. I used a stereo splitter cable from £/$ store to get the wired 3.5mm inline socket. The 2.5mm plug I wired but again it could be obtained from a 2.5mm to 3.5mm audio cable if you didn't want to have to solder one up.
The version 2 of this unit now features a trim pot (22K) in place of R3 ( the wiper connects to C3) so that you can adjust the level of the bias signal sent to the FZ200. Adjust to about 1/3 or the rotation as a starting point. Do a test recording with the unit on and adjust the trim pot until the background noise doesn't increase when you stop talking.
AGC Control for Panasonic Lumix FZ200
This is work in progress to produce a small device which will defeat the automatic gain control (AGC) of the FZ200 camera when using external microphones.
The AGC is responsible for keeping the audio recording levels at a point which is audible but not clipping causing distortion.
In most situations where the audio is constant this circuit performs well. However, in other situations like interviews, music recording and dictation there may be brief periods where there is no audio input. During this period the camera AGC will attempt to raise the background noise from the mic or its own pre-amp circuits to the normal level. You can here this as random hiss noise on the recorded audio track. As soon as the audio breaks this silence the camera AGC has to then quickly turn down the gain to get the audio back under control. The first second of this might be distorted as the AGC has a hysteresis lag.
I have been working on a small unit which will be battery powered and will allow you to plug an external stereo mic into it and then this unit plugs into the 2.5mm mic input socket of the camera.
In operation this unit generates an inaudible 20KHz signal of about 6-8 millivolts and is combined with the left hand channel of the audio. As this waveform is what the camera would expect to see for average recording at the right level no change in the AGC is made if the input volume decreases. It will still control the passages which exceed this recording waveform. As it is over the normal threshold for hearing the audio track does not contain this and cannot be heard.
The initial proof of concept uses a commercial waveform generator IC however my final design will be a much smaller unit using smaller and discrete electronic components. Here is the proof of concept at the moment
Here is the test of the unit in the proof of concept stage.
I now have a prototype of the simplified version and her is the video test
Studio Flash Equipment for Amateurs
whilst not everybody needs to invest in studio grade flash equipment I thought that I would share my experience in trying to put together a simple, cost effective system that I could use for general photography in my small studio space. For most purposes I can use speedlites with a guide number of 50 metres or more at ISO 100 and trigger then either optically, or increasingly these days using wireless triggers. Larger, more powerful flash heads give more creative possibilities but I didn't want to have to spend lots of money on something that doesn't get a lot of use.
I settled for the Godox systems using the AD200 (200 watt second) and the AD600 (600 watt second units).
The AD200 is quite a remarkable, dual flash head, system. It has a conventional xenon fresnel lens speedlite head with a guide number of 52 and it also has a bare bulb flash head with a guide number of 62. The bare bulb head can be modified with any number of reflectors and, if mounted in the Bowens type adaptor plate (as seen in the top illustration) can be used with an even more extensive range of flash modifiers.
The AD200, at a push, can be hand help and triggered by an on-camera Godox "X" series transmitter (Canon,Nikon or Sony) however it is quite a heavy (0.5Kg)unit despite being only the size of a regular speedlite. It is lithium-ion powered and recycles in just 2 seconds from a full power discharge
The AD600 is just a bare bulb unit with LED modelling light. again lithium-ion powered and recycles in just 2.5 seconds from a full power flash discharge. It is too heavy to hand hold and is supplied with a handle which can be fitted to a conventional lighting stand.
Both units have a 3.5mm sync port so they can be used with any remote cable triggering device and support the S1 and S2 optical trigger modes for instantaneous and pre-flash suppression modes.
Wireless Flash Trigger Systems
wireless trigger systems have evolved to quite an advanced level now.
It is possible to get systems which will transmit the TTL data from the camera to the flash enabling full TTL control without the need for extension cables from the hot shoe to the flash
unit. The Godox "X" system is such an example of this implementation. It is currently only available for Canon, Nikon and Sony flash systems to enable full TTL control. It can however be used to
trigger manual flash guns and also act as a remote shutter release as well.
Wireless triggers have a superior performance over optical (line of sight) devices. They have a range of up to 80 metres or so outdoors and can pass through solid walls and floors making them ideal for situations where the camera and flash are in different locations or out of line of sight.
With the Godox "X" system normally a dedicated transmitter and receiver pair are used to link the host camera and the flash unit. It can, however be used to provide centre pin firing on nearly all flash units which have the capability of being able to be set up in a manual power mode. In the example above the Canon system transmitter pair are firing the Nikon flash unit. The camera can be any camera capable of triggering via the centre electrode.
Audio Equipment For Videographers
Getting good audio quality for your video productions is almost, if not equal to, getting the right lighting and exposure!
Viewers may be tolerant of out of focus or badly lit shots but poor audio quality is likely to be a big turn off.
It needn't cost a fortune to improve the audio quality of your productions and in this section I will introduce you to a few ideas that might help you do this.
The biggest improvement that you can make is to use an external microphone. The internal mics are omnidirectional and pick up sound sources all around the camera. Handling noises, the image stabiliser whirring in the lens barrel and generally they are too far away from the subject in an interview type situation. They are good for providing a perfectly synched audio track from another external recording source such as a portable audio recorder.
The external mic ideally should be "off-camera" and close to the sound source however even a directional "on-camera" mic can make a vast difference to your sound production.
Let's begin by looking at the cheapest option and one, which surprisingly, gives really good audio quality for interviews, voice overs and commentaries etc.
A simple £3 ($) electret condenser lavaliere (tie clip) mic can be plugged directly into the mic port of the FZ300/330/1000/2000 or with a 3.5 to 2.5mm adaptor into the FZ200.
They usually come with just a couple of metres (6 feet) or so of cable so it might be necessary to add a 3.5mm extension cable to allow you to rig the mic without danger of pulling over the camera!
I have used over 6 metres (20 feet) of cable without any noise/hum pick up.
When positioned about 20cms ( 8 inch) from the mouth and clipped to a shirt/blouse/coat etc will give surprisingly good audio. because of the close proximity to the sound source the mic level can be turned down in the camera and this will help to reduce other ambient noises.
The mics are omni-directional so will pick up sound from all directions. You can mount the mic with the front port facing down and this will help prevent "popping" noises on some syllables.
A step up in quality is the use of a self powered electret condenser mic such as the one shown opposite - the Audio Technica ATR3350
(or the Boya mic http://amzn.to/2mHAdPZ) £16 ($).
This mic has its own inbuilt silver oxide battery which lasts for ages and has abot 6 metres (20 feet) of cable terminating in a 3.5mm (1/8 inch) plug.
It will work directly with cameras with the 3.5mm mic port or via a 3.5mm to 2.5mm adaptor on the FZ200.
Sound quality is excellent with very little electrical noise. Again the mic level can be reduced to help with ambient noise reduction.
If you are worried about the possibility of walking away from the camera whilst still attached via the lavaliere mic (yes it does happen)
then the next alternative would be a "wireless system" like the one opposite. Its a UHF system so wireless interference is very much reduced. The range is over 80 metres (200 feet) outdoors.
Again audio quality is excellent and it gives you a lot more freedom during your presentations etc.
For isolating unwanted sound a "rifle" mic is often recommended such as the one shown opposite the Boya BY PVM1000
This is a self powered (single AA alkaline battery) electret condenser microphone with XLR (and phantom 48v power) connection.
Although this isn't the ideal location for this type of microphone it is better than the internal mics.
The ideal placement for such a mic is directly overhead the subject with the mic pointing down.
The front lobe pickup from the mic then picks up the voice whilst the super cardioid pickup pattern (where the side of the mic are largely insensitive to external sound) help to reduce any other ambient sounds
For videos or podcasts where the mic being in view doesn't really matter then the studio condenser mic is a good choice. The BM-800 is only about £23 ($) and comes with its own shock mount system. Some suppliers also offer table stands or full mic stands to support the mic.
It can be powered from the camera by the slight bias voltage which appears at the mic input port but best operation is attained by using a phantom powered pre-amp system.
Again because of the close proximity to the speakers mouth the sound is rich an d golden and again ambient noise is reduced by being able to reduce the mic input gain level.
Above is one of my recording setups for use with the FZ2000 but it could be used on any camera system.
A BM-800 studio mic, the ATR 3350 lavaliere mic, the Saramonic smart rig+ for the phantom power and mic pre-amp and a pair of headphones for audio monitoring.
An alternative system utilising the Boya BY-PVM1000 rifle mic and the Saramonic SR-AX100 power supply/pre-amp unit.
LED Light Panels - Looking at what they exactly offer the stills or videographer.
I think we can all agree that natural daylight is probably the best light source we can use to create our images and video clips. Even in harsh sunlight we can employ techniques to tame it into the quality that we might need for a particular photoshoot. The use of reflectors and diffusers are some of the techniques that I have previously covered to show how to do this - particularly when photographing flowers as too much contrast kills the delicate tonal shades and destroys the very fine detail that we can see in petals etc.
But what about indoors when sunlight is not available such as after darkness fall?
Traditionally this was the place that tungsten lighting was employed. Photoflood bulbs and reflector lamps were the key components and I can still remember many a burned finger trying to adjust the position of these lights!
but today with advancement in LED lighting more and more studios are converting to LED light panels if they do not shoot with studio flash equipment. Running costs are more lower, the heat generated is far less and some can be self powered meaning there is less likelihood of trip hazards from trailing power cables.
This is a typical 10 x 12 inch LED light panel from Yongnuo.
It has 600 LED's and can be adjusted fro 0 to 100% brightness in fine incremental steps.
At first you would imagine that the light output from these large panels would be adequate for both stills and videography as they do look very bright when turned on and set to maximum intensity.
In reality the light output is actually quite low and two or three lights may be needed, especially for video work where we need to use shutter speeds of around 1/60 second. For commercial work where the subjects are static then long exposure times can be used. However for portraiture type work large apertures may be required, or higher ISO settings, in order to make these work in this situation.
Apart from light intensity there are two other factors which must be considered when choosing and using these lights; colour temperature and colour rendering index (CRI).
Having just acquired a new app for my smartphone it makes it very easy to measure colour temperature now rather than having to shoot an image and look at it photoshop or lightroom
It was these two later parameters that I wanted to investigate more so I did a series of tests on the LED lights that I most frequently use and which are still generally available for sale on Amazon or Ebay.
To do the tests I used the Canon 5D mark 3 as Canon digital colour science, in my opinion, is extremely good.
I shot a series of test images using a 18% grey white balance card and a colour checker patch in daylight and with each of the LED's. I kept the LED's at exactly 1 metre from the subject to that I could get a comparative Light Level reading in LUX and translate this into exposure times at f5.6 and ISO 100.
This is a typical image from the test series:
Using the camera in AWB (auto white balance) enabled me to also see the range of automatic adjustment made by the camera in each colour temperature situation.
The meter shows the measure light level in Lux (x10) and I have indicated the camera exposure to give the correct exposure for the gray card. The colour patches show any variation in light output in terms of RGB as traditionally low CRI LED's may have green spikes or low red outputs.
here is the full gallery of the test images.
This is the Aputure AL-528W by Amaran:
It measured 5200K, so pretty close to daylight and produced 3000 lux at 1 metre with the diffuser fitted. Without it there is a slight noticeable fall off in this image set but the light increased to 4460 lux giving 1/3 stop extra light.
When the 3200K CTO filter that is supplied was fitted the light level dropped dramatically to just under 1000 lux and just over 1 f-stop needed to correct the exposure. Note how this shift was not accurately corrected by the Canon 5D mk3 - quite a surprise! it took a further adjustment in adobe photoshop to render the gray card correctly as seen in the last image.
This is the MCOPLUS LE-520B, soon to be replaced by two more powerful units.
I note I have made a mistake in labelling the lux output - it should be 780 and700 Lux, not 7800 and 7000 in images 1 and 3!
This is a two bank LED system, one bank made from 3200K LED's and the other one 5500K. This obviously drops the power output as only half the lights are on (unless you switch both banks on)
the measured colour temperature was slightly warm at 5130K with the 55K bank on but pretty close at 3140k with the 3200K bank on.
Again the %D was not able to correct the white balance and post processing was needed to bring the white balance back to neutral.
Exposure times were down to 1/13 sec to produce the correct exposure at 1 metre distance.
This is the Yongnuo 300 LED panel which is just one colour temperature. Again it measured slightly warm at 5060K in the supposed 5400K daylight mode. Quite a good output from this light although it is more compact and casts stronger shadows as it is more of a pin point light source compared to the larger panels. With the diffuser removed it gave 1/3 f-stop increase in light.
The two remaining lights were the typical small 32 and 64 LED lights sold as hot shoe mounted video lights.
With outputs down at 1/3 second these are really totally unsuited to video work unless the camera is within a few inches of your subject. They hardly produce enough light for fill in if used on camera in bright conditions out doors and at 67K are too cold to try and mix with tungsten light if filming indoors. They can me used as small accent lights in some scenes but not by any means key lighting.
So in summary what have I learned from this testing?
Well it confirmed that the newer light panels are now pretty close to their advertised colour temperatures and don't need colour gelling to get the right temperature. Colour rendering across all the lights now looks perfectly adequate for most amateur lighting use and when a manual white balance in camera is performed should give some very accurate colour reproduction.
What was a total surprise was the fact that the Canon 5D mk3 was unable to apply enough correction in the AWB mode to correct for scenes shot with the CTO orange filter fitted on the fixed temperature lights or with the 3200k LED lights.
The final composite is a sample of the LED lights showing the relative outputs, colour temperature and colour rendering