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If you are involved in table-top or macro photography, you know how important good light is. It used to cost a lot of money and electricity, but now you buy three cheap LED photo lamps with even cheaper small tripods. We looked at the TF-96 LED photo lamp from Ulanzi. |
Introduction to the Ulanzi FT-96 LED photo lamp
What you get for your money
This LED lamp is offered by almost all well-known Chinese mail order companies for a price starting at € 13.50. Note however! Some companies include a rechargeable battery, others do not supply this battery. The lamp comes in a sturdy cardboard box that easily survives the way Chinese parcels are shipped. The box contains the lamp plus two transparent lids. One is completely transparent, the other is yellow. One closes the front with the LEDs, the other the back with the batteries. By changing these two covers you can adjust the color temperature of the light. Both covers should not be screwed on, but magnetically attached to the housing. Very handy and well thought out! In addition, a small black cloth bag is supplied in which you can transport the lamp.
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| The contents of the package. (© 2018 Jos Verstraten) |
In the image below we have joined the front and back of the FT-96 lamp into one photo. You can clearly see the two transparent lids that protect the front and back and which you swap in five seconds thanks to the magnets. At the top is a tumbler switch, by which you switch the lamp on and off. On the side is a dial for adjusting the intensity of the LEDs. Not visible is a micro-USB connection on the bottom, which allows you to power the lamp from a 5 V USB power supply. However, a cable is not included in the most inexpensive version of the lamp.
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| The front and back of the FT-96 lamp. (© 2018 Jos Verstraten) |
You can power the lamp in three different ways:
- From four 1.5 V type AA cells. If you use rechargeable types, this is definitely the cheapest solution. Please note, however, that you cannot charge these cells via the micro-USB connector! Also make sure that you place the four cells in the same direction in the battery compartment.
- Via the BP-4L rechargeable battery. It delivers 3.7 V and has a capacity of 2,500 mAh. There are two metal strips in the battery compartment that make contact with the battery when you clamp it into the compartment. The BP-4L is a readily available lithium-polymer battery that is also used in some Nokia smartphones. For this battery you pay (in China) about € 4.50.
- Via a 5 V USB power supply with a cable with micro USB connector. However, this power supply must be able to supply 2.5 A current.
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| The battery compartment with four 1.5 V cells or one BP-4L battery. (© 2018 Jos Verstraten) |
- Number of LEDs: 96
- Maximum power: 9 W
- Supply voltage: 3.7 Vdc ~ 6.0 Vdc
- Colour temperature without filter: 5,500 K (standard daylight)
- Colour temperature with filter: 3,200 K (halogen lamp)
- Light flux: 860 lm
- Beam angle: 120°
- Mounting: hot shoe and 1/4 inch thread
- Dimensions: 105 mm x 70 mm x 37 mm (without hot shoe)
- Weight: 142 g (without battery or cells)
The internal of the FT-96 LED photo lamp
Of course we are always very curious about the internal of a device. Fortunately, you can easily open the FT-96 and the picture below will appear. You can see that the four 1.5 V cells are wired in series, from which the maximum supply voltage of 6 V can be explained. Next to the battery compartment is a very small PCB with a rotary potentiometer, a micro-USB connector and the two contacts that connect the battery. The construction looks very solid, the on/off switch is of good quality and easy to use.
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| The unscrewed FT-96 photo lamp. (© 2018 Jos Verstraten) |
The PCB can also be easily removed from the housing. The PCB contains a 555 timer and a second chip which, on further investigation, turns out to be a TC4953 dual P-channel MOSFET. The two MOSFET's are connected in parallel and have an internal resistance of only 53 mΩ each. They can handle 4.9 A current at a maximum reverse voltage of 30 V. An electronic component that is therefore heavily over-dimensioned for this application, which undoubtedly benefits the long-term reliability.
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| The small PCB in the FT-96. (© 2018 Jos Verstraten) |
The FT-96 LED photo lamp in practice
Supply and power consumption
We have powered the FT-96 from a stabilised 6.0 V power supply. The lamp consumes a maximum current of 2.36 A from this voltage, which corresponds to a power consumption of 14.16 W. That is a lot more than the specified 9 W.
The functioning of the intensity control
With the potentiometer on the PCB you can control the intensity. On this PCB is a 555 timer-IC and it is therefore obvious to assume that this circuit works according to the principle of pulse width modulation. In the picture below you see the voltage offered to the LEDs. This voltage is switched with a frequency of about 65 kHz. Unfortunately, this intensity control is not to full satisfaction, the signal does not really look good. The intensity of the LEDs can only be partially reduced. At a certain moment the LEDs suddenly go out completely. The applied principle of pulse width modulation would, if it had been applied correctly, allow a complete and smooth control of the intensity of the LEDs.
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| The pulse width modulated voltage across the LEDs. (© 2018 Jos Verstraten) |
The hot shoe allows you to attach this LED light directly to a photo or video camera. The 1/4 inch hole with screw thread allows you to quickly screw the FT-96 to a standard photo tripod. Such a small tripod is already for sale for € 7.50. So you already have a nice stable lamp for table-top photography for just over twenty euros. With three such lamps you can light up your objects beautifully without shadows. Thanks to the intensity control, however limited the effect may be, you can still apply beautiful soft shadow effects in your shots by making one of the LED lamps shine a little less brightly.
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| The FT-96 on a tripod or directly on the camera. (© 2018 Jos Verstraten) |
Our opinion on the FT-96 from Ulanzi
We bought three of these LED lamps with tripods to provide the articles on this blog with well exposed photos of the reviewed electronic products and their PCBs. A nice example of what also for you can be a great hobby: table-top photography. We power the three lamps with cheap rechargeable 1.5 V cells type 'LADDA 1000' from IKEA. Despite the malfunctioning intensity control of the FT-96, we are very pleased with these LED lamps. They offer an extremely cheap and quick to install solution for perfect illumination of small objects. The possibility of quickly changing the colour filters is also extremely pleasant in practice. You can quickly experiment with the influence of applying a yellow colour filter to one or more of these lamps.
Ulanzi 96-LED Video-Light
