Bulb Analyzer Tool (actualized)

knna · 08-27-2008, 01:45 PM

Since the Bulb Comparision Tool thread has became too long, ive decided to post the actualized version of the tool on a new thread.

Needed lighting concepts to develop LED grow lights. This thead is complementary of this one, as explain the importance of some of the parameters calculated by the sheet.

This time i just upload the finished version of the Bulbs Analizer Tool on the three basic formats (for 1, 5 and 10nm wavebands), without loading it with digitalized SPDs. I upload too a tool to help digitalizing SPDs wich have some already SPDs digitalized.

Copy one and paste it to the correct model to use the sheet. You need to fill in yellow cells to get the results, offered in blue cells.

I did the sheet using OpenOffice,a free Office suite, but i upload too the xls version for MS Excel users.

knna

PS:8-10-08 Hand digitalizer upgraded (bugs fixed and more SPDs added)

knna · 09-21-2008, 09:32 AM

-White cells: contain info needed to perform calculations. Dont change them (the sheet is unprotected and there is no hidden cells or macros; i let all the basic info displayed to allow anybody to upgrade the sheet).

-Green cells: headers of columns/rows/single cells. They say what are the info following it.

-Blue cells: they show calculated results

-Yellow cells: these are what you need to fill in to use the sheet.

The first row with the header "SPD of" is the tittle of the sheet. Fill in it with the lamp (manufacturer and model) to be analyzed (for example, Phillips SON-T Agro).

The most important info to fill in the sheet is the SPD (spectral power distribution) data. Its on the column B, below the final results. Ill post detailed instructions to get this data for yourself on the next message. For the moment, to learn to use the tool, copy one SPD from the "Hand Digitalizer Tool" wich has some of them saved. Paste it to the SPD column, starting below the green "SPD" header. If you want to keep the format of the sheet, use the "special paste" option by rightclicking the mouse, select only the "numbers" choice and disable the rest.

You can copy a full column in a single paste. You just need to click the first cell to be copied and move the cursor over the column up the final cell keeping the button pushed. Or by clicking the first cell and clicking the final one while pushing "SHIFT". All the cells get selected, rightclick and select "copy".

Once the SPD column has been filled, you have the results that only depends of the SPD. The spectral results are offered on the blue cells on the upper right corner. This data are fully independent of the model's wattage. They are, from up to bottom:

-LER (Luminous Efficacy of Radiation): figure given is how many lumen generates each PAR watt. The higher this figure, the more lm a lamp achieves for the same energy emission. Or the reverse, as higher LER, less energy (PAR watts) for each lm (or Klm=1000lm).

-PPF/Klm (Photosynthetic Photon Flux/1000lm): the figure correspond to how many micromols of photons holds 1000lm of that SPD. Its very useful to determine irradiance at top of plants, just by measuring with a light meter. The figure is the same for PPF/Klux, and lightmeters uses luxes (or footcandle; 1 fc=9.76 lux). So if you take a reading with a luxometer, divide reading by 1000 (3455 lx=3.455Klx, just put a .) and mutiplies it by the figure given in this cell, you obtain the irradiance in micromols of photons.

This method only work for unshaded areas. In shaded areas, spectrum has changed so you cant apply the PPF/Klm figure calculated for the SPD. But when possible, this way gives a irradiance figure without the need of using expensive quantum meters, and accuracy is very good.

Irradiance figure, or PPFD (PPF Density) on the technical literature, given in micromols of photons per second (abreviated, uE) per sq meter is the most relevant figure you want to know to improve your grow lighting.

PYF/PPF (wide) figure uses the full range 380-780nm instead of the standard PAR (400-700nm).

PYF (Photosynthetic Yield Flux) and PUR (Photosynthetic Usable Radiation) are two ways of estimating the ability of a number of photons to promote photosynthesis (plant growth). They are only aproximative, as plants adapt themselves to the light quality, so its impossible to use a universal valid conversion, as what is used to calculate lm for humans.

PYF is calculated weighting PPF by the McCree's curve after derating PPF for the average cannabis absorbance of photons at each wavelenght. Whyle PUR is calculated weighting PAR watts by the Inada's curve.

So PYF/Klm and PUR/Klm figures serves to calculate "plant lumens" from a luxmeter reading. While PYF/PPF and PUR/PAR Watts inform of how good is the spectrum alone for plants. The higher the figure, the better the spectrum.

Important note: In this context, "better" means more ability to promote plant growth. It dont inform about quality. This estimation are only useful on condition of low-medium irradiances. They arnt valid for saturated photosynthesis or CO2 limited conditions, found under high irradiances (what happen on most MJ grows, at least at canopy level), where qualitative analysis are required, as there is no studies about it.

R/B: Red to blue ratio. 4 or less correspond often to lights used in the vegetative, while over it correspond to flowering lights. Its given as ratio of uE or of PAR watts.

R/Fr: Red to far red ratio.

φ Pfr/Ptot: Phytocrome's photoestationary equilibrium. The higher the figure (max 0.89), the less stretching the light promotes, aswell as shorter but thicker leaves and some other biological effects (as effect on flowering induction and crop maturation). Lights with this figure below 0.75 promotes stretching. All lights used for growing have this figure bewteen 0.75-0.89. A good way to know if a spectrum isnt good for growing is when this figure is way below 0.75 (incandescents lamps are about 0.25).

-Blue, Green and Red percentages (of total PAR light). Its given both as percentage of photons (P) or PAR Watts (W). Names are simplified, as blue cover 400-500nm, green 500-600 and red 600-700.

PPF/PAR watt: uE that holds each PAR watt.

In order to analyze a concrete model, is required to fill in the data of that lamp. The sheet allows to calculate results for up to 12 differents lamps emiting same spectrum. In fluorescents, its pretty common to have a wide range of wattages and formats (T5, T8...) emiting same spectrum. This way you can see all in a single page, or compare how a different ballast or format affect results.

For each lamp to be analyzed, you need to fill the 6 yellow cells below the "wattage #" header, so you get its results below it. Data to fill in are:

-Nominal watts: watts of the lamp, 400, 600w, etc

-Actual watts: mostly, its the same than nominal, but not always. For example the Phillips SON T Agro 400w draws 430w actually. If you dont know actual watts, put the same than nominal.

-System watts:watts consumed for the bulb and its ballast (when required). The most accurate result from the sheet are obtained when this data is accurate, as there are wide differences between ballasts for same lamp. Precise data of ballast manufacturer are usually required to fill in this cell accuratelly. In case you dont know how many power lose your ballast, use a 15% (70-250w), 10% (400w) or 7% (600-1000w) of the power of the lamp. For example, a generic 400w HPS draw 400watts+ 10% of 400 (40watts)=440 watts. For floro ballasts, use a 10%.

Most data of the sheet are refered to system watts.

Klm (1000lm): lm emission of the bulb divided by 1000.

Price: optional info. If you want to compare how profitable are each option you are considering to purchase.

Useful Life: optional. Defined as time to reach 80% of initial emission, it allows to compare long term costs of different lamps.

If you let this last cell in blank, results associated to them are not shown (obviously). System watts and Klm are required.

Results are shown inmediatelly below. Bulb and system efficiency gives the percentaje of the burned power that is emited as PAR watts.

PPF, PUR and PYF are already explained. In this cells are shown figures of the lamp analyzed (corresponding data above).

Ratios per system watt (PPF/W...) gives it per each burned watts, so you can compare easily different wattage models perfomance.

Ratios per $ (or the currency you entered in the price yellow cell) gives them for each $ of initial cost. Price of each uE is the best measure of cost of a lamp.

Ratios per $ along the useful life of the bulb allows to analyze long term costs.

Heat load (of the bulb alone) or system Heat Load gives the amount of watts to be cooled. Any unit converter (you can use google directly for it) may covert it to cal or BTU or whatever unit you know of your AC system.

If something is not clear, just ask.

knna

knna · 10-07-2008, 04:49 PM

Im going to show how to digitalize a spectral power distrubution (SPD) graph in order to analyze it with the tool.

Obviously, you need to have a SPD graph to analyze.Im going to use MS paint to do it. To edit a graph with it, righ click the file and select the option "Edit". It open directly MS paint with the graph in it:

You need to do some steps to digitalize it easily:

1-From the scale in the X axis of the graph, wich is given in nanometers (nm), calculate its width in nm (end of the axis minus start of the axis). Almost all SPDs cover either 400-700nm or 380-780nm (preferable), thus they have a width of 300 or 400nm.

The example has a with of 785-380=405nm. But ill ignore the last 5nm waveband, as the analyzer tool only has a range up to 780nm.

2-Remaining operations are performed better using a larger graph size and the squared mode. To do it, resize the image to 400% by clicking on the top bar on "view", select "zoom" and click on large size.

You can do it directly by pushing Ctrl+Av Pg. By pushing Ctrl+m after it, you put on the squared mode (or go again to "view", "zoom" and "show squares").

3-Adjust the horizontal size (x axis) of the pic in the way it has same pixels than nm. Thus each pixel will correspond to a one nm waveband. To do it, first you need to know the width in pixels of the graph:

3a-Put the pointer on the left edde of the x axis and take note of the pixel number, wich is shown on the bottom right. It shows two numbers splitted by a ",". The first correspond to the x axis coordinate and the second is the y axis coordinate. Now we are interested on the first number (x axis).

(The screenshots dont show the pointer. Its on the left bottom corner of the graph. As graph's lines are 3 pixels thick, i put the pointed on the middle pixel)

Do the same putting the pointer on the last pixel of the x axis. The second minus the first gives you the graph width on pixels.

So in the example, it has a width of 848-60=788 pixels.

3b-Now divide the width on nm by the width on pixels. Multiply it by 100. Round the entire part of the figure from the closest decimal (sum 1 if the first decimal is 5 or higher).

Example: 400nm / 788pixels=0.507*100=50.7 wich is rounded to 51.

Click on "Image" on the top bar, "expand or reduce" (or directly, Ctrl+w). A dialog box appears. Enter the figure you get on the last operation on the first (upper) box (expanding horizontally). It dont mind if the figure is lower than 100. It works the same way.

Now you should have the same width on pixels than in nm. But as the expand tool not accept decimals, sometimes there is one or two pixels of difference. So check the pixel width of the graph again (step 3a). If its not the same than nm width, repeat step 3b (likely you'll get 99 or 101). If it still dont works, reduce size to any figure, as 57%, and start again. But it usually works at the first or at least, the second try.

Matching accurately pixels and nm is important on 1nm resolution graphs. In the example, its a 5nm wavebands resolution, so it dont mind. Each 5nm width column is clear, and you can check there is 8 5nm columns in each 40nm division of the graph.

4-Optional. Highlight a single pixel for each nm on the SPD curve. This step does easier entering data on the tool and help reducing errors associated to hand digitalizing a graph. Just select a color with the stronger contrast with the color of the graph (by clicking it on the bottom left of Paint) and go clicking on a single pixel that represent better the emission on that nm.

Very often,lines are some pixels thick, so you need to choose if highlighting the upper, middle or lower pixel. As far as you use always same criteria, its valid. Differences due different criteria are under the error margin associated to digitalizing a graph. On other ocasions, emission raises/drops sharply on a few nm, resulting on a vertical line with several pixels on the same nm waveband. In this cases, seek for the darker pixel. If there is some, try to see whats the shape of the line to select the most accurate or select a criteria, as the half point of darker pixels and use same criteria in all cases.

While this step is advisable on SPDs using 1nm wavebands, those using longer waveband of 5-10nm, that appears as columns often dont require doing it, as the top of the columns is clear.

(continue)

knna · 10-08-2008, 04:30 AM

Now the graph is ready to be digitalized easily.

5-Entering data into the hand digitalizer tool.

Open the hand digitalizer tool and resize both windows (MS Paint and Hand Digitalizer tool) so you can work with them together, like this:

(If you dont know how to resize a window, its very easy: go to the upper right corner and click on the "maximize/restore" icon next to the "x" icon that closes the window. Now put the pointer on a edge of the window: it turns to a double arrow. Push the mouse button and move the mouse to the desired size, while keeping the button pushed. Unpush the button and its done. If you need to move the window, click on the top colored bar of the window and move it keeping the buttom pushed).

The example pic has some data already filled in. Details on 5a and 5b:

5a-Select the right model (1,5 or 10nm wavebands) for the graph. You do it clicking on the right sheet on the bottom left:

5b-Check the vertical pixel number (y coordinate, explained on step 3a) on the bottom line of the graph and enter it on the only yellow cell of the B column in the tool (headed "pixel bottom"). Now click of the first yellow cell of the C column so you can start entering data if the graph starts at 381nm. If not, fill all the cells until you reach what correspond to the first nm of the graph (likely 401nm) with the same figure than the bottom line of the graph (its the "0" value)

To fill the C column of the sheet, put the pointer over the desired pixel of the line (if you did step 4, the pixel highlighted). Check the number of the y coordinate (second number on the bottom of MS Paint), enter it and press "Return" ("Enter"). Now the next cell is activated. Put the pointer on the next waveband pixel, enter it and press return. And so on until you reach the last waveband.

Following this procedure, you dont need to move the pointer between Paint and the tool. Put the pointer over the pixel, enter the data of it with the keyboard, then move the pointer to the next pixel, enter with the keyboard....You just need to move the pointer when you need to move the graph.

When you reach a divisor line, check you are entering pixel height on the right nm waveband. Doing this periodically avoid to reenter all the data if you jumped over a pixel.

Be aware some times two or more adyacent columns have same value, so they appear as a longer waveband. Remember to fill both wavebands with the same figure:

6c-Now you have entered all the raw data. You have digitalized the graph. Before doing anything else, save the data. The SPD final data is shown on the D column. Single click the first yellow cell of this column. Then go down and while pressing "shift" click the last cell. All cells get ready to be copied together (they gets a darker color). Right click and select "copy".

The hand digitalize tool has a 4th sheet for it, tittled "SPDs". Select it by clicking it on the bottom of the sheet. Go to a free column, click on the second cell and righclick, select "special paste" and disable all the options on the left except the "numbers" one and accept.You already have copied the SPD. Now write the name of the SPD on the first cell. Save the sheet ("file" and "save").

Now you have digitalized the SPD graph sucessfully, so you may analyze it with the bulb's analyzer tool

The procedure is easier to do than to read. Its just a bit boring entering the data. Once you have done this, you will realize its very simple to do.

The idea is you digitalize your bulb if still its not on the digitalized SPD's library (the SPD's sheet of the hand digitalizer tool) and upload it, so next GC's member using same bulb will just need to copy it. An hour of work not only serve you to know better how you are lighting your plants, but its a service to other GC's members.

This way i hope we will have all bulbs SPDs digitalized soon.

knna · 10-08-2008, 05:32 AM

When having the SPD already digitalized, using the Bulb's analyzer tool is very easy:

Open the BA tool and select the right model sheet (1,5 or 10nm waveband).

1-Opening a new sheet.

A safe thumb of rule is to copy it on a new calc spreadsheet, so if you do any mistake, you dont need to download it again. Let the models as backput of the sheet.

In order to do it, go to the upper right corner and click on "Files", "New", "calc sheet". By default it opens sheet with three pages.

If you already have it and you just need to add a new page, go to the bottom, where you select between the different pages, rightclick and select "Insert sheet".

2-Copying the BA's model.

Click on the right upper corner of the model sheet (the empty square linking columns and raws). All the sheet change of color (you have selected all it). Move the pointer over the sheet, rightclick (if you leftclick, you undo the selection) and select "copy".

Go to the just opened sheet (step 1), rightclick and select "paste"

Now you have a copy of the sheet ready to be used.

3-Copying a digitalized SPD.

Go to the SPD's library and copy the selected SPD (explained on 6c of last post). Go to your new sheet, click on the first yellow column below hte green header "SPD", then rightclick and select "special paste". Like on 6c, select only paste numbers.

After this step, now you have avalaible the spectral analysis. Its shown on the upper right:

4-Analyzing a given model.

You may analyze up to 12 different lamps using emitting same SPD on each sheet. It may be different wattages (mostly) or for example, different combinations of bulb/ballast.

For analyzing a given lamp, you need to fill in its data:

As noted on the 2nd post, you must fill in at least wattage and emission on Klm (1000lm).

In this case, i dont have price info, so i wont get any data related to that:

I hope you will find the BA tool useful.

knna

knna · 10-08-2008, 05:49 AM

At this point, i need some help to further improve the BA tool.

Im not a programmer. So i dont know if it could be possible to do easier the proccess of digitalizing a SPD. I think it could be doable to make a program that saves in a log, or directly to a sheet the x,y coordinates of pixels when pushing a given keyboard combination. This for sure would help a lot digitalizing.

Other nice improvement would be building a database with the data from all the bulbs, so we can easily do tables with the ratings of all bulbs analyzed about different parameters (PPF/W, PAR W/w, PYF/PPF, etc), wich i think is what most people are interested to know.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Day Length Tool	outdoors	Growing Outdoors	5	03-14-2008 06:12 PM

New To Site?	Need Help?
Register to Participate View Forum Leaders Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Hot Products: