Light curve photometry or photometry evolved a long way to improve light designing for engineers since its inception.
Photometry is a graphical representation of determining different complex issues and light intensity for viewers’ personal vision. To have a potential view and lighting perspective, this is a great arrangement to develop different lighting options and designs.
History of photometry
Photometry has a long history to determine asteroid’s positions and light spectrum. Great scientists and philosophers have developed telescope.
But the telescope has limited use. To get maximum output and more detailed analysis, photometry has been invented.
In the later part of 1700, Edmund Halley recognized that there is a spectrum difference between different stars. The first magnitude – stars are far brighter than fifth-magnitude stars.
The next development came from British Scientist Norman Pogson. He developed a logarithmic scale. This scale is governed by the following equation.
∆mag= -2.5 Log (b1/b2)………………………………………………………………………………………………………….(1)
Here B1 and B2 are the brightness object
Here negative sign is used because the brightness is upside down. On this scale, more negative means more light.
Color Based system
The earlier color-based systems are visual and photographic. In this color-based system, the magnitude is quite different than any other combination. To have better quality lighting and spectrum efficiency, this method can be used.
When a photograph is valued in order of different spectrums, then the different colors will provide various aspects.
To have better quality lighting and spectral difference, the color efficiency holds the key for better quality measurement. The modern multicolor schemes have been developed in the 1930s.
Photoelectric Photometry
Photoelectric photometry is one of the critical resources invented for quite a long time. But the resource is optimized with low efficiency.
A recent development in the photoelectric effect has significant improvement. This photoelectric effect will provide the necessary output for better spectrum management.
Most of the quality output and significant development will increase the performance to a great effect.
This excellent photometry will enhance the performance of a significant effect. Recent photomultiplier tube development has changed the complete turnaround.
Johnson Cousins standard
Since 1950, Johnson and Morgan have developed a great strategy to devise the standard procedure. This excellent standard will help the photometry to a significant effect. This superb band uses smart U Band structure to develop the issues.
How to set the standard for photometry
The definition of standard photometry is fundamental to determine different values to a significant effect. To have potential photometry and super quality designs, you need to focus on a different set of colors and wavelengths.
The terms related to photometry
Fig: The photometry working Principle
The word pertaining to photometry are as followed
- Lumens – luminous flux
- Candela= the unit of light intensity
- Foot candles- luminous measured in foot candles
- Candelas/ meter2- this is the unit in the vision. This is what eyes perceived.
- Cutoff angels – is the angle between the vertical axis and the cutoff signs.
Other information related to photometry
- Test Number- this number is used to determine the type of lights and their parameters.
- Lamp information- This information is used for initial candle output and parameters of light.
- Beam spread- a maximum of 50 percent of the candela power is the beam spread.
- Centre beam candle power- At the bottom, the maximum candle power is called the Centre beam Candle power.
- Efficiency- efficiency is the ratio of luminaire output and lamp output.
- Unit LPW- to define the system efficacy.
Bare lamp versus Real-World Data
The empty lamp has a difference with the real-world data. This real-world data is essential to improve the performance of an individual lamp. The bare lamp data is a manufacture date.
This excellent Bare lamp data is different than the real lamp data due to some working conditions like coning, wall preference, decoration color, and so on. Let’s have a look at the table.
| Description | Voltage | Foot candles |
|---|---|---|
| Published Bare Lamp Data | 12 | 361 |
| Off the shelf bare Lamp | 12 | 320 |
| Off the shelf lamp as tested | 12 | 252 |
| Corrected for X former on the switch | 11.8 | 237 |
| Corrected for laminated Xformer on the switch | 11.5 | 217 |
| Corrected for a laminated transformer on the dimmer | 10.6 | 161 |
Point to Point calculation
Point to point calculation is one of the prime requirements for luminaire selection. This excellent lamp is ideal for high-quality point to point communication. This magnificent light technology is crucial for superior quality control and operation.
This accurate point-to-point measurement can be obtained using a trigonometric calculation. There are several methods. We are discussing the most basic calculation.
Formula 1: FC= (IxN)/D*D
Formula 2: FC= (I* cosθ)/ (D*D)
Cone color Finish Multiplier
This is one of the crucial measurements regarding the reflector. Based on different luminaires and their base, the reflector is designed with precise calculation. For better projection and quality reflectors, you need to focus on different reflectors.
To have different reflectors and potential analysis, the cone color finish multiplier has a significant effect.
This excellent quality reflector will provide excellent performance and greater directions. Let’s look at the table to have a look at some comparison.
| Description | Cat | Nondirectional Lamps | Directional Lamps |
|---|---|---|---|
| Clear | C | 1 | 1 |
| Black | B | 0.23 | 0.93 |
| Blush | Bu | 0.85 | 0.99 |
| Blush Haze | BUH | 0.74 | 0.98 |
| Chocolate | CC | 0.38 | 0.93 |
| Chocolate Haze | CCH | 0.31 | 0.95 |
| Coconut | K | 0.58 | 0.95 |
Light loss factor
There is an essential parameter in the forms of light loss factor. This excellent light loss factor is quite evident in lamp selection. There are several lighting options available.
Incandescent lights are quite fascinating, but their loss is greater than halogen and complete fluorescent lights. Let’s have a look at the potential table for lighting options.
| Source | LLD |
|---|---|
| Incandescent | 0.87 |
| Quartz halogen | 0.95 |
| Compact Flouroscent | 0.95 |
These are the most critical parameter before using any photometry solution. Photometry is an advanced tool to create potential output from a lighting perspective.
In this excellent lighting solution, these different parameters, along with others to have high potential laminations.
This excellent lighting solution will provide super quality lighting and professional settings. You can have different parameters to determine the right light.
Correct lighting will reduce electricity bills as well as efficient environment pollution reductions.