Macro Photography

0.005sec (1/200); f/13; Focal Length:105 mm; ISO Speed:640;Exposure Bias:0 EV;Flash fired; using 12 and 20mm extension tube

Received Kenko extension tube set this week. Today I have a play with it.

My favourite subject is ladybird. Though very small, it is a very beautiful beetle with bright red shell doted. The size–about 5-7mm-presents a serious challenge for macro photography.

Back earlier April, I used Macro function comes with the lenses for close up shooting, which can be manually focus (with moving camera back and forth) at around 0.45m distance. The finished shoots after crop and interpolation(up size of the digital image by calculated and filling the pixels) become blur at edges. This is understandable-the finished photo I used as desktop is actually 4 times the life size by digital up scaling, counting the actual projection size of the beetle on the CCD sensor(or film emersion) it is much smaller. Later I will show you image magnification ratio chart.

0.005sec (1/200); f/9; Focal Length:105 mm; ISO Speed:100;Exposure Bias:0 EV;Flash No; Using Macro function

It must be optical magnification to solve the problem properly rather than resize the digital image. There are few solutions around, such like use reverse ring to mount a 50mm lenses reversely. Use a bellow or an extension tube. Each solution has its pros and corns.

Reverse ring is the cheapest solution. you can pick up one from eBay for around £5 including postage from China. It exposed the lenses inside out, without proection to the lenses element it could be a hazardous. And of course you lost TTL metering and auto focus.

Bellow is the most flexible but quite bulky. It takes a platform with ruler and guiding rails. I feel it is not the best choose for field shooting. I saw one on eBay going for £160 with a compliment 50mm FD lenses. A new one without lenses shipped from China costs about 30 pounds includes p&p.

That leaves candidate extension tube. By mounting it ( or combine a few and) to camera body, then mount lenses to it, you have the balance of flexibility, portable and lenses protection.
There are two types of extension tubes around. The economical one costs around £10 pounds, it doesn’t come with electronic contact points, so the camera and your AF, TTL lenses are disconnected. The one I brought made by Kenko comes with build-in contact points, it relays the communication between lenses and camera body. So it retains TTL metering and auto focusing. Costs £55 pounds from HK. About the price I paid for a 50mm 1.8F prime lenses. Consider there is no lenses, no motor and no circuit board but just 3 aluminium rings, it is quite expensive.

shown with 12, 20 and 36mm extension tubes mounted (See the red dots behind the lenses?)

Anyway I am quite excited to have a new gadget under my belt.

Global warming speeds up this Spring. Back three weeks ago there are a lot of ladybirds around our garden, now they all seemed gone away. So it is very lucky I found a fella basking sun in the grass.

First I mounted a 25mm tube and set our little friend to a tulip leave. Didn’t use flash as the sunlight was still strong. Auto-focus is usable, but not very useful as the field of depth is very shallow regardless aperture: a little motion from the subject will mean refocusing. And the auto focusing is just not fast enough to cope. The strong wind didn’t help neither. With the magnifying effect from the tube, it renders subject violent movement.

After a few attempts, I retreated. Took my little model with the stem he is resting on and set the shooting studio over dinning table.

I use flash mounted with diffuser. First I try 25mm, then 25mm plus 12mm and finally 25mm plus 12mm plus 36mm. At the beginning I didn’t bother to set up tripod, thinking with speed at 1/200 and image stabiliser, it should be alright without – I was wrong, later I checked the photos and found there are compromised on quality.

With all three tubes mounted, the Maginification ratio increased to 6.1 for a 50mm lenses. I zoomed to around 100mm so the shake from the hands were even apparent. So a tripod is a must. In fact I use release cable and set the custom function to enable mirror lockup.


0.005sec (1/320); f/9; Focal Length:105 mm; ISO Speed:400; Exposure Bias:-1EV;Flash No; Using 20mm extension tube

0.005sec (1/320); f/9; Focal Length:105 mm; ISO Speed:400; Exposure Bias:-1EV;Flash fired; Using 12, 20 and 36mm extension tube

After shooting, I resize the photo to be the same as the CCD size - for Canon 5D it is 23.84 x 35.8mm then measure the beetle’s size then compares to it is actual size: 6mm. Here is the actual magnification ratio chart:
(Setup) (CCD Projection size) (Mag. ratio)

macro: 2.8mm 0.467

12,20 36mm ex.tube: 8.5mm 1.417 (approx.)

12 and 20mm ex.tube: 7.6mm 1.267

20mm ex.tube: 3.75mm 0.625 (approx.)

P.S. Also found Cannon 5D handles high ISO noise quite well. With noise reduction switch on, it only becomes visibly grainy at 1000 or above.

My close up shooting album.

Custom configuration with nested collections in .Net 2.0

I am writing this as a brain dump.

Has been played around with .NET 2.0 strong type configuration this weekend (a bit late, I know). After some uneven drive-thanks to the lack of documentation- I finally produce a custom configuration file like the one below.

(For my work colleagues at Talis, yeah you - I know you will check my blog – If you are wondering why I am not using the time on our project for RDF Java configuration. Honestly, I do. I mean you absorb and learn from a competing technology, getting ideas from patterns, even the naming convention it uses – particularly there is Reflector for sneaking around.)

Here is the custom configuration setting with nested collection:
<section name="workflowConfig" type="Jingye.Workflow.Exe.WorkflowConfigSectionHandler,Workflow" />
…

<workflowConfig seperateProcesses="true" processWaitTime="50000">
<setup workingPath="c:\temp\" />
<workflow name="WorkflowOne" interval="15" dailyRun="true" startTime="09">
<task name="task1" onError="Abort"/>
<task name="task2" onError="Log" />
</workflow>
<workflow name="WorkflowTwo" interval="9999" dailyRun="true" startTime="08">
<task name="anotherTask1" onError="Abort"/>
<task name="anotherTask2" onError="Log" />
</workflow>
</workflowConfig>

Some well-known bits and bobs
1. Where is my config file?
For web app, this setting is in web.config. It will be picked up by ConfigutationManager as the default config file.
For console app or win service, you need to tell the Configuration about this file.
1) The short form. You app.exe.config file should be side by side with app.exe. Framework will ‘intelligently’ figure out the path and suffix ‘.config’ to the exe.
Configuration config = ConfigurationManager.OpenExeConfiguration("Workflow.exe");
WorkflowConfigSectionHandler scheduler = (WorkflowConfigSectionHandler)config.GetSection("workflowConfig");

2) The long form. The short form wraps this long form for convenient sake, but if you want to load a config from a different location or even pass in as command line argument, these are the lines to use

ExeConfigurationFileMap fileMap = new ExeConfigurationFileMap();
// relative path names possible
fileMap.ExeConfigFilename = @"c:\temp\exe\ConfigTest.exe.config";
// Open another config file
Configuration config =
ConfigurationManager.OpenMappedExeConfiguration(fileMap,
ConfigurationUserLevel.None);

//read/write from it as usual
ConfigurationSection mySection = config.GetSection("workflowConfig");

2. Your configuration section - the root derives from System.Configuration.ConfigurationSection. Back in .Net 1.x era, this is traditionally called XXXXHandler as it implements IConfigurationSectionHandler interface.

3. Each configuration element is declared as class derives from ConfigurationElement. Configuration element can have child elements, again derives from ConfigurationElement.

4. Configration elements take attributes/properties - decorates class properties with ConfigurationProperty. However configuration element doesn’t take CDATA text as body.

[ConfigurationProperty("seperateProcesses", DefaultValue = "true", IsRequired = false, IsDefaultCollection = true)]

5. Assign a key property in ConfigurationPropertyAttribute decoration. Such like ‘name’. You will need this to locate your configuration element in a MAP.

6. If a config element is a collection such like this, you also need to implement a façade to manage access to each member, this MyConfigElementCollection class is derived from ConfigurationElementCollection class.

Less well-known bits about MyConfigElementCollection class

1. By default, MyConfigElementCollection uses AddRemoveClearMap as its merging semantics – meaning how machine.config and your web.config or app.exe.config should merge together.
You can override this to be BasicMap or AddRemoveClearMapAlternate or BasicMapAlternate. Mark Gabarra discusses each of this merging semantic in his blog “.Net Configuration Default Behaviour”, worth a read if you are wondering ‘how could I stop downstream config changes my setting?’

public override ConfigurationElementCollectionType CollectionType
{
get{ return ConfigurationElementCollectionType.BasicMap;}
}

2. Override ElementName, if you are not using AddRemoveClearMap or just find another ‘<add>’ being confusing to the guy actually uses your app.
By default, ElementName is “” (String.Empty), because in AddRemoveClearMapAlternate semantic, elements should be view as ‘operation instructions’ – add, remove or clear an element. The real name of the element is passed in the strong typing context, hence anonymous is acceptable. Nevertheless, it is less self-describing to the user.
protected override string ElementName
{ get { return "workflow"; } }

3. In the parent element, where an instance of this element or a collection of this elements is declared, give the default name – “” as the name in ConfigurationProperty.
[ConfigurationProperty("", IsRequired = false, IsDefaultCollection = true)]
public WorkflowConfigElementCollection Workflows
{
get
{ return (WorkflowConfigElementCollection)base[""]; }
set
{ base[""] = value; }
}

I find this is confusing at the beginning, but if link back to point 2, it all make sense on how reflection and serialization works.

Reference:
Mark Gabarra, blog “.Net Configuration Default Behaviour”
Jason Diamond blogs on using call back custom validator: Custom Configuration Validator Weirdness
Alois Kraus: Read/Write App.Config with NET 2.0

Five things

Five Things about you and five firends of yours

Admit that it is hard for me to come with five friends who blogg, this is difficult. And my Talisian colleagues are moving fast – I would say although your colleagues are your friends (at least in theory), you are not meant to tag them as this spirals into a workspace dead loop.
Now I am pulling my hair for the five coz Rob exhausts (almost) all work-bloggers I know, thanks also goes to Ian (internet alchemy) D too. No, nil, zero, no one (Andy, I leave Sarah to your account).

So if you wonder who this quietly Jingye is, here is the five of him:

1. I got to gym at least five times a week, do a 5km/30mins run before finishing the day.
2. I consume around 500 minutes podcast each week, mostly IT and digital photography related. My most favourite is BBC documentary archives and the least favourite is IBM Institute for Business Value.
3. Danni, my wife and I have recently completed a 25 km charity walk for British Heart Foundation at the Peak District.
4. My latest gadget is a Canon 5D digital camera. Here is one (more are in my flickr).
5. I organise outdoor activities for the alike Chinese expats in Britain. Our next call is ‘Winter Farm Experience’ at Lake District.

And here are five friends of mine: mumu, xp, flywhc, TheTime, Sisyphus