Light Level (lx) Test Introduction

Introduction

DataSweet’s Data Logging module includes features that will change the way

students are able to analyse data and present their experiments in a

completely new medium, added to this is the ease-of-use that DataSweet

brings to data logging. Data logging devices, and their sensors, are

automatically detected as they are plugged-in. Recording video is done with

the click of a switch. Read below to find out what you can do with data

logging.

A Great Modern Application for Mac OS X

DataSweet makes full use of the modern

features that Mac OS X has to offer. The

graphs and meters are drawn using the

latest Quartz® graphics technology,

which means beautifully presented

graphics that can be copy and pasted from the clipboard with no loss in

quality.

Create Movies of your

Experiments

It’s all about time!

Logging data happens over a period

of time. The medium of video also

plays along a time line, so it's completely natural that a data logging

experiment should be presented as a movie. The Data Logging module

creates movies from your captured data with animated graphs and meter

readings being displayed exactly as they were when the data was captured.

Capture Video as you Log your Experiments

DataSweet has the facility to record video while logging

data from your experiment. This breakthrough feature

means students can present their experiments and

findings though the medium of digital video.

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Fetch Files from a Data Logger

If the data logging device supports

remote logging then DataSweet is able

to fetch this data from the device.

DataSweet presents a list of files stored

in the data logger with information

about each data file along with the time

and date when the data was captured.

Supported Devices

The Data Logging module supports the

following devices:

LogIT devices from DCP Microdevelopments

Explorer, Voyager, Blackbox, SensorLink and

DataMeter 1000. If you are using a DataMeter

1000 or an older Explorer with a serial port

then you will need to purchase a serial to USB

adaptor lead from DCP Microdevelopments.

Data Harvest

EasySense Q3, Q3+, Q5, Q5+, Advanced and EasySense Link.

Support for other devices will be added in the future.

http://www.dcpmicro.com/

http://www.dcpmicro.com/

http://www.dataharvest.co.uk

http://www.dataharvest.co.uk

System Requirements

A Macintosh computer running Mac OS X 10.4 or later, a minimum of 256 MB

of memory is recommended.

iLife ‘04 containing iMovie version 4 or higher if you wish to export and edit

an iMovie project.

The DataSweet application requires around 5 MB of disc space.

User Requirements

To be generally familiar with using the Mac OS X operating system, launching

applications, opening and saving files.

Installation

1. Insert the CD ROM into the CD/DVD ROM drive.

2. Run the DataSweet package and follow the instructions in the installer.

3. Once installation is complete, run the DataSweet application from the

Applications folder on your computer.

4. Choose Register Software… from the DataSweet application menu.

5. Enter your details and the serial number which can be found on the licence

card included in the software pack.

If you have correctly entered your serial number then the Register button

should become enabled. Click on the Register button, you should only

need to do this once.

Connecting a Data Logger

You do not need to install any drivers for use with either the DCP or Data

Harvest devices, DataSweet takes care of all of this for you.

1. Simply connect the device to a powered USB port on the Macintosh.

If DataSweet has been previously run, then by default, plugging in a

supported data logging device will automatically launch DataSweet with a

data logging template.

This document is copyright © Kudlian Software Limited 2009

This manual documents the features in DataSweet – Data Logging

Published: Monday, 20 April 2009

Getting Started

When you launch DataSweet a new

document will be created and a

sheet will drop down asking you to

choose a DataSweet document

template.

1. Select the Data Logging template and click the Choose button. A new data

logging document will be created as shown:

The main document window displays by default a graph of any logged data.

When you create a new document there is no data to be displayed.

Logging Data

Automatic Logging

Let’s get started and log some data so that we can see how DataSweet lets

you present your experiment.

If you have a supported device plugged into the computer then the

Start Logging item on the toolbar should be enabled.

Ensure that the device has any necessary sensors plugged in and

we’re ready to start collecting data.

Click the Start Logging button.

As the sensor values are read from the device DataSweet will display them as

a graph in the main document window. Try and get the sensors to change

their readings by either pointing a light sensor at a light source, making some

noise for a sound sensor or squeeze a temperature sensor to raise its

readings.

When you have finished click the button that now reads Stop Logging.

Underneath the graph you will see that the timeline is enabled.

Click on the play button and DataSweet will playback the graph as when it

was collecting the data.

At anytime you can pause the playback to click and drag the time marker up

and down the time line.

Changing the Time Scale

The slider to the right and under the timeline allows you to scale the time

displayed on the horizontal axis of the graph. By dragging the slider knob to

the right, you can zoom in on the graph over time. If you now playback the

graph then you will see that it scrolls along as it plays.

Changing the Playback Rate

You can also adjust the playback rate. If you have carried out a data logging

experiment over a long period of time then the graph will playback very

slowly, i.e. at the same rate as the experiment took. Increasing the playback

rate means that you can create an animated graph playing back the

experiment much quicker. To do this:

1. Either click on the stepper buttons to the right of the playback rate text

field or click in the text field and enter a value directly.

If you have carried out an experiment over many days then you may need

to increase the playback rate to around 10,000 before you see the graph

start to draw.

The Graph pane in the inspector allows you to control how the graph is

displayed and you can use this to analysis various aspects of the data.

Saving and Opening

Documents

DataSweet saves and opens documents in the typical way that a document

based application does on Mac OS X.

To save a document:

Choose File > Save from the menu bar.

To open a document:

Either double click on the document you wish to open from the Finder or

choose File > Open… from the menu bar and navigate to the document you

wish to open.

You can also use the File > Open Recent > item on the menu bar to quickly

open any recently saved or edited documents.

The Inspector

The inspector window opens by default with the main document window and it

allows you to control and configure how data is logged, how the graph is

presented and also provides some analysis information as well. Each pane in

the inspector is designed to be used progressively as you carry out a data

logging experiment.

Devices

The devices pane displays a list of data

logging devices currently plugged into the

computer. Each device has a set of sensors

which may be either internal to the device or

externally plugged-in. By default all of these

sensors will be read when you start logging.

Additional information such as a device's

battery level is also shown where appropriate.

To find out information on the device and

sensors:

1. Click on the device in the device browser to

view additional information about the device

and its battery level where appropriate.

When a device is selected, clicking on the devices item in the menu bar

offers additional options such as setting its clock and a security stamp.

Some devices also support the facility to fetch data that has been logged

remotely.

2. If necessary click on the disclosure triangle to view the device's sensors.

3. Click on the sensors to view additional information on the sensors.

4. Before you start logging you can click on the check boxes to select which

sensors are going to be recorded. If you log a sensor that isn’t important to

you then you can later choose not to display that sensor in the graph,

however you cannot later retrieve a sensor’s values that were not logged.

5. Each sensor is represented by a colour on the graph. You can later change

this colour when we start to configure the graph.

Note: Do not confuse this table of devices and sensors with those shown in

the Graph pane. The devices and sensors displayed here are those that are

currently plugged into the computer whilst those shown in the graph pane are

the devices and sensors that were used when the data was logged.

Settings

The settings pane allows you to set various

logging options before you start logging. Once

you have logged data in the document these

settings are disabled. There are three types of

logging: Automatic, Manual and Snapshot.

With automatic and manual you can set both

the log rate and the maximum number of

readings.

You also use this pane to tell DataSweet to

record video while logging data.

Automatic Logging

Automatic logging is most suitable when you do not know how long the

experiment will take. It does not require any setting up although you can set

the initial log rate and the maximum number of readings if you wish.

Once the maximum number of readings is reached, the log rate is halved and

half of the previous readings are discarded. This continues until the maximum

number of readings is reached again. When using automatic logging you must

tell DataSweet when you wish to stop logging by clicking the Stop Logging

button on the toolbar.

Manual Logging

Manual logging means that you set the rate at which you wish to capture

sensor readings and how many readings you wish to capture, together these

settings then determine how long the logging will take place and DataSweet

will display this time when you select Manual.

To increase the length of time over which logging will occur it is better to set

the log rate to a longer time than to just keep increasing the number of

readings. 1000 readings is usually enough samples to give a smooth graph.

You start logging in the same manner as automatic by clicking on the Start

Logging button. You can click on Stop Logging at any time to stop the logging

but if not then DataSweet will automatically stop logging once the required

number of readings have been sampled.

Snapshot Logging

If Snapshot logging is selected then the sensor readings are captured on

demand and are displayed as a bar chart rather than a line graph.

To start snapshot logging:

1. Click on the Start Logging button on the toolbar.

2. Click on the Store Reading button from the toolbar or choose Analysis >

Store Reading from the menu bar. You can also use the keyboard shortcut

⎇⌘S.

3. When you have finished capturing readings, click on the Stop Logging

button.

Recording Video

For more information on recording video please refer to the Recording Video

chapter.

Meters

The meters pane shows a list of meters which

display the values of the sensors for the

currently selected item in the data table.

As data is captured the meters display the

value of each sensor at that time and they also

display the current reading when playing back

the captured data.

Graph Settings

The graph settings pane lets you configure various options for the display of

the graph.

You can choose which sensor readings you wish to view and their colour,

which sensor’s scales are used for the Y-axis and how much of the graph is

displayed if you have made a time selection. The axis can also be set to auto

scale and a grid can also be displayed on the graph.

To change the graph settings:

1. Click on the check boxes in the Show

column to choose whether to display that

sensor in the graph.

2. Click and choose from the pop-up menus

which sensor’s units should be displayed

either in the left or right axis.

3. Click on the other check boxes to auto scale

the axis, display a time marker, to show

markers set during logging, whether the

graph only displays the data for the time

selection or to display a grid.

Each of the graph settings are retained as part of the current clip. You can

therefore set different settings for each clip. Further information on clips can

be found in the section Creating Multiple Movie Clips.

Layout

The layout pane allows you to set various options to configure the content of

the movie preview.

You can choose from a variety of backgrounds

and set which sensor’s meters you would like

to be displayed. Each object in the layout can

be moved around and have various settings

changed.

1. Click on the check box for each item in the

list to set whether it is displayed.

2. Each item in the preview can be dragged to

reposition it where required.

3. The video and graph can be resized in the

movie preview if they are not set as the background item.

Like the graph settings, each of the layout settings are retained as part of the

current clip. Further information on clips can be found in the section Creating

Multiple Movie Clips.

The graphic below illustrates how you can layout the movie preview:

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Analysis

The analysis pane lets you smooth the

captured data and displays statistics for each

sensor.

Each sensor can have different smoothing

attributes applied and statistics for each sensor

can be selected and copied to the clipboard.

Data Smoothing

When data is captured from each sensor you

can sometimes see lines on the graph rapidly

jumping up and down over each time interval, we call this noise. It may

become obvious if you auto scale the axis with a sensor whose readings vary

over a small range, for example when looking at small rises or falls of

temperature. By smoothing the data the noise is removed and the line on the

graph will display a general trend for how the values of the sensor changed

over time.

How to smooth the captured data:

1. Select the sensor for the data you wish to smooth.

2. Click on the segmented control to either use the preset Auto settings, or

Advanced if you want more control over how the data is smoothed.

3. Repeat for any other sensors.

The data smoothing works by averaging a number of values either side of

each sample.

The greater the smoothing factor the further away from each sample is the

averaging calculated which has a greater tendency to remove large spikes.

By default we use a central moving average, that is we calculate the average

by looking at the values either side of each sample, you can also choose to

use a prior moving average which only averages the values prior, or before,

the sample being averaged. This has a tendency to drag sample values back

to the previous values thus slowing down any changes in the graph.

For each type of average you can choose whether to use an arithmetic

weighting or no weighting. The arithmetic weighting gives greater emphasis

to the sample value being averaged and less emphasis to values further away

from it. This means that any large, sudden changes in values are better

reflected in the graph.

The Auto setting uses a central moving average, with a smoothing factor of

20 with arithmetic weighting.

Statistics

The statistics text field displays the minimum, maximum and average values

for each sensor. By clicking on this field you can select and copy the text to

the clipboard which can then be pasted either into the Notes for the

experiment or any other application that accepts text input.

Note: The values displayed are those after the data has been smoothed. This

can sometimes substantially affect the minimum and maximum values,

although the average values should remain relatively unchanged.

Recording Video

DataSweet has the facility to record video while logging data from your

experiment. DataSweet will work with built-in and external iSight cameras, a

DV camcorder and the iMage webcam.

To record video while logging data:

1. Click on the settings button either on the main toolbar or the inspector's

toolbar.

2. In the section labelled Video: check the Record Video button.

If everything is working correctly, you should now see a preview of the

video in the graph view.

Once you start logging, the video will be recorded along with any data

logged from the logging device.

Troubleshooting Camera Problems

If you are having problems with your camera we suggest you go through each

of these check points.

• Check that there are no other applications running that are also using the

camera. These might include: iMovie, iChat, Photo Booth, I Can Animate…

• If it is a DV camcorder, you will need to ensure that the tape is removed

and that it is running from a power supply and not its battery. You should

also check that it is not configured to run in a 'demo mode'.

• If it is a webcam, you must be sure that it is compatible with your

Macintosh. We can supply small webcams that are compatible with the

Macintosh. Further information on the iMage webcam can be found here.

If you are already using the iMage webcam, please ensure that you have

installed the necessary driver for it.

• You might need to download and reinstall QuickTime. We are aware that

sometimes users do not have all the necessary QuickTime components to

use video cameras. You can download QuickTime from here.

https://www.kudlian.net/products/imagewebcam/




http://www.apple.com/quicktime/download/

http://www.apple.com/quicktime/download/

Fetching Data Files

DataSweet can download data files from a device that has been used to log

data remotely. To do this:

1. Select the device that you wish to fetch the data from in the devices pane in

the inspector.

2. Click on the Fetch Data item on the toolbar of the document window or

choose Device > Fetch Data from the menu bar.

If there are any data files to download then a sheet will drop down listing the

data files on the device.

The sheet will list each file in a table along with the start time and data, the

log rate and the number of readings.

3. Select the data file you wish to download and click Fetch.

The data will be downloaded and you can view and playback the graph as

you would with data that has been logged using DataSweet.

Exporting Data and Video

DataSweet allows you to export your captured data in various formats.

Exporting the Data

Data can be exported either as CSV, (comma separated values), tab

separated values or text. The text format is the same as TAB but with the .txt

and .tsv respective file extension.

To export a data file:

1. Choose File > Export… from the menu bar.

2. Choose the appropriate file format from the pop-up menu.

3. Save the file in the usual manner.

Copy Table Data to the Clipboard

When you are viewing the table of data, the data can also be copied to the

clipboard as tab separated values. This data can be pasted into a number of

applications that paste tabular data.

To copy the table of data to the clipboard:

1. Click the Table tab button to display the table of data.

2. Click the table of data so that it has the blue focus ring around it.

3. Either choose Edit > Copy from the menu bar or use the keyboard shortcut

⌘C.

Exporting a Movie

Movies can be exported in two formats; either as a folder containing each clip

as a separate movie file or as an iMovie project. This project file is for use

with the previous version of iMovie or as it was later known iMovie HD. If you

are using iMovie 7 or later then you are better to export the folder of clips and

import each clip into iMovie.

To export a movie:

1. Choose File > Export from the menu bar.

2. Choose the appropriate movie format from the pop-up menu.

3. Save in the usual manner.

Sharing a Movie to iTunes

DataSweet can also share your movie directly to iTunes. This is particularly

useful if you want to display your experiment on a device such as an iPod as

the movie needs to be in a particular format in order to be played on either

the classic iPod, iPod Touch or iPhone.

To send the movie to iTunes:

1. Choose Share > Send Movie to iTunes from the menu bar.

2. Select an appropriate format from the pop-up menu and click Export.

Copying the Graph to the Clipboard

You can also copy the graph, and any displayed meters and video to the

clipboard as a single graphic for pasting into another application that

supports the pasting of graphic files. The graphic is copied to the clipboard as

both a loss less PDF and TIFF formatted graphic. This means that if the PDF

graphic is pasted into an application the resolution of all the graphics and

shadings remains beautifully sharp and crisp at high resolutions.

To copy the graph to the clipboard:

1. Click the Graph tab button to display the table of data.

2. Click on the graph so that it has the blue focus ring around it.

3. Either choose Edit > Copy from the menu bar or use the keyboard shortcut

⌘C.

Creating Multiple Movie Clips

You may find during your experiment that there a number of interesting

moments that you only wish to include in your movie. You can do this by

selecting a region of the graph by clicking and dragging the selection markers

on the time line.

Under the time line there is a disclosure button labelled Show Clips.

1. Click on the Show Clips disclosure button to reveal the clips drawer.

By default there is always at least one clip and you cannot delete it. Many of

the graph and layout settings are contained within the selected clip. When you

have the selection and layout that you wish, clicking on the + button in the

clips drawer will create and select a duplicate clip. Now any changes you

make to the graph settings and layout, including the time selection, will be

part of the new clip. Changing the selected clip will change the selection and

layout for that clip. Each clip can also be given a name which is used when

the clip is exported as an iMovie project.

Once you have exported the clips you can import them into an application

such as iMovie to add transitions, titles and perhaps a voice over to the movie

presentation.

Miscellaneous Settings

There are various features within DataSweet that you can use to help

administer your data logging devices. If any of these menu items are disabled

it is because either you do not have the device selected in the devices browser

in the inspector or because the device does not support this feature.

Set Date and Time

Some data logging devices will allow you to use the computer to set their

internal clock’s date and time. This can be easier than trying to do it through

the device’s interface. To set the date and time:

1. Select the device in the Devices pane in the inspector.

2. Choose Device > Set Date and Time from the menu bar.

Set Security Stamp

Some data logging devices allow you to set a security stamp so that you can

uniquely identify the device. Currently this is only supported by Explorer,

Voyager and Blackbox. If the device supports this feature and the security

stamp can be read then DataSweet uses this text within the devices browser in

the inspector. To set the security stamp:


2. Choose Device > Set Security Stamp from the menu bar.

A sheet will appear that requests the text for the security stamp and a

password to protect students from setting this to an undesirable value.

Upload System Software

Some data logging devices allow you to update the system software that is

used in the device. To update the system software:


2. Choose Device > Upload System Software from the menu bar.

This item may also be disabled if the device already has the most up-to-

date system software.

Light Level (lx) Test Introduction

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