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image: Edward H. Adelson

Every sense we use to communicate with can be tricked, or confused into perceiving things that don't exist and not perceiving things that do exist.  Our senses are good at what they do, but have limitations and adaptations that work for or against us in a certain way.  If we know the limitations, we can better compensate using other techniques.

Optical Illusions

Take the image above for example. Are the squares A and B the same color, or are they different colors?  They are the same color. Adelson of MIT explains the checker shadow illusion and why these appear to be different colors, but are in fact the same color.  Both colors are the hex color code #777777.  The visual system breaks down what it sees into components, allowing us to perceive the nature of what we see.  In this case, assumptions on physical space and light lead us to a false conclusion.

In one study, at the Visual Cognition Lab at the University of Illinois, individuals were asked to count how many passes of a basketball were made by a specific team.  Interestingly enough, about half failed to notice a gorilla that moves across the court and pounds it's chest.

Some key points on optical illusions (visual communication limitations):

1. We see things that aren't there.
2. We don't see things that are there.
3. Focus or stress causes us to overlook things we would normally notice.

If our eyes can be deceived, then so can our other senses.  When we try to communicate, we use written, visual, verbal, and nonverbal means to convey our message.  Just like the optical illusion above, in every mode of communication there is the opportunity for illusions of communication to occur which can often lead to miscommunication.

Verbal Illusions

Speakers overestimate their effectiveness.  I've known this from personal experience, but I wasn't aware of the significant degree of miscommunication that occurs.  Experiments by Boaz Keysar and Anne Henly proved to me verbal illusions exist just as do optical illusions.

1. Speakers are confident they are effective even if the information is ambiguous or unclear.
2. Speakers are not understood as much as they think they are (less than ½ the time).
3. Listeners are confident in understanding speakers
4. Listeners do not understand as much as they think they do (less than ½ the time).
5. Listeners are as confident when they are understanding correctly as when they misunderstand.
6. Observers (not involved in the exchange) are more likely to identify potential misunderstandings.
7. People that are anxious or depressed are more likely to incorrectly process ambiguous situations as threatening.

Written Illusions

Written communication can be even more prone to miscommunication.  Ambiguity in verbal communications is even more detrimental to miscommunication in written form (e-mail, documents, requirements, etc.). Communication that takes place in written form is devoid of explanation, original intent, body language and inflexion that come with communication in person.  Furthermore, most written communication tends to be viewed as more formal.

Think about it, if written communication were so easy and clear, why does the U.S. Constitution call for a panel of justices on the supreme Court to interpret the written laws?

Compensate for Illusions

We see things that aren't there, we don't see things that are.  We think we hear things, clearly, but don't.  No wonder software development projects fail.  If we want to communicate better, what can we do?

When I was the chairman of the ActiveStore committee, I worked with team members from multiple companies in Europe, Asia, the Middle East, and the US.  I learned that these senior people (presidents, vice presidents, directors)  were good at communicating, but not immune from these illusions of communication.  We would discuss a topic, come to a conclusion, reach an agreement, and then write it down.  We found that only by using multiple avenues of communication (white boards, verbal, in-person meetings, and written summaries), did we actually agree on what we were trying to communicate. 

I've since then worked with development and customer teams in four or five different physical locations, anywhere from 700 to 7000 miles apart.  The problem only gets more complicated and complex the further the distance is involved.  I've used the following points to help me communicate clearly.

1. The burden of communication falls on the communicator.
2. Assume only ½ of what is communicated is understood.
3. Repeat important communication points multiple times in different ways.
4. Don't be ambiguous, be specific.
5. Have the recipient repeat what is understood.
6. If something can be interpreted in multiple ways, clarify the original intent.
7. Have the recipient state assumptions that are made.

Every instance that I have seen where there were significant gaps in what was expected versus what's been delivered in a software development project have all been preceded by  little explanation, and large assumptions that were not clearly communicated.  I've seen the above techniques clearing up communicating help improve understandings significantly.

References

• Optical Illusions & Visual Phenomena
• New insights into the neural basis of anxiety
• Troxler effect

photo: Willi Heidelbach stock xchng

It's not that software is never finished.  It's just that done is not a good description to describe the status of software.

What's the status of the "Buy 12 get one free promotion?"

It's done!

What's done for one particular team isn't done for another.  Done for the business analyst isn't done for the the person doing deployment.  It leads to a lot of confusion among teams, particularly when teams are in multiple physical locations.

What's needed to help communicate the status is a common set of terms used by the teams in all locations to consistently indicate status.  I use the following terms with my teams.  This not only helps identify the status of a particular feature, it takes the emphasis off a particular phase and helps the team realize that one shot isn't the game.  Half time isn't done.  The goal of a software service or product is to rollout the features desired by the business, not to just complete one particular phase.

1. Business requirements complete
2. Graphical User Interface (GUI) requirements complete
3. System requirements complete
4. Technical design complete
5. Code construction complete
6. Code review complete
7. Code review changes complete
8. Unit test complete
9. Unit test issues changes complete
10. First pass system test complete
11. System test issues complete
12. Final system test complete
13. Customer acceptance test complete
14. Customer acceptance issues complete
15. Deployment complete
16. Pilot complete
17. Rollout complete

In the days of global development teams, communication can be difficult.  It's what the recipient hears that is more important than what the communicator says.

What was said:

I believe in you. Love, Mose

What was heard:

I be leaving you. Love, Mose.

The next time you communicate with your team members, get them to repeat what they understood in their words.  It's better to straighten out any misunderstandings up front than to let things go misunderstood.

The full entry from December 2007 Reader's Digest:

My wife struggled with a career crisis: Should she quit her job? Knowing how panicked she was, I called our florist and sent her a bouquet with a card saying "I believe in you. Love Mose." Later she called to thank me. "But I'm confused by the card," she said. "Really? Why?" "Because it reads 'I be leaving you. Love, Mose.'"

On Dec 9, Microsoft released the ASP.NET 3.5 Extensions CTP Preview for Visual Studio 2008.  Scott Guthrie outlines some  ASP.NET 3.5 Extensions CTP Preview key features this preview release provides.

These include:

• ASP.NET Ajax Improvements
• ASP.NET MVC
• ASP.NET Dynamic Data Support
• ASP.NET Silverlight Support
• ADO.NET Data Services

A set of ASP.NET 3.5 quickstart samples are also available. 

A quick take:

Q: Should I use this for production development?
A: No, this is a CTP Preivew.  See the ASP.NET Product Roadmap for more information.

Q: If I shouldn't use this for production development, what good is this release?
A: It provides the ASP.NET MVC which if your requirements need it provide the ability for enhanced URL control for your ASP.NET applications.  Previously, the only ways to do a very complex URL structure was a painstaking folder path, or installing an Isapi extension.

On November 19, 2007, Microsoft released Visual Studio 2008.  Scott Guthrie outlines some of the Visual Studio 2008 key features.

Some reasons on why you may want to upgrade.

Key VS 2008 Features

• Full tool support in VS 2008 for WF, WCF, and WPF
• Target builds for .Net 2.0, 3.0 or 3.5
• Java Script intellisense and richer Java Script debugging
• Nested ASP.Net master pages
• Rich CSS editing and layout support within the WYSIWYG designer 
• Continued support for web site and web application project models
• ASP.NET AJAX support
• ASP.NET 3.5 ListView control
• LINQ (language integrated query) support
• Intellisense code editing improvements

Key .Net 3.5 Features

• LINQ support
• ASP.NET AJAX
• New WCF Protocols (including AJAX, JSON, REST, POX, RSS, ATOM, and several new WS-* standards)
• New base class library features

Silverlight 1.1 tools and Web Deployment project add-ins are not available at this time.

Microsoft released .Net 3.0 for VS 2005 earlier.  This added support for new Microsoft technologies for WPF, WCF, and WWF for the existing VS 2005 IDE.  Although the technology was there, the lack of typical IDE tools made the use of some of these very very awkward (how fun is it to really modify XAML files directly).  WPF really needed Microsoft Expression and WCF needed hand generation via tools of the proxy clients and hand configuration of configuration settings. The integration of these technologies into the VS 2008 IDE really brings these back in line with the typical VS.NET development environment.

Some releases like VS 2003 to 2005 require significant migration steps.  When this happens it requires significant development time, expense, and planning and that makes the update process painful and slower to adopt.  The most painful step in the process is the number of hours it takes to download the DVD ISO image from the MSDN web site.  The first pass is that existing windows forms applications will migrate somewhat painlessly, web application projects remain to be tested.

There should be no hesitation in updating to this release.  If you update, you can still target builds for .Net 2.0, 3.0, and 3.5, so you aren't forced to update anything from a deployment perspective just yet and yet you get the benefit of the updated IDE. 

If you haven't tried the Microsoft tools, there are also a set of  Visual Studio Express editions that are free.

Microsoft announced on Nov 19, 2007 the availability of Visual Studio 2008.  It also made available to the public a free version of the developer tools.  Check out the following links to obtain your free copy of these tools.

• Visual Basic 2008 Express Edition
• Visual C# 2008 Express Edition
• Visual C++ 2008 Express Edition
• Visual Web Developer 2008 Express Edition
• Popfly
• SQL Server Express
• SQL Server Compact Edition

The Visual Web Developer version includes a significantly improved HTML web designer also used in Visual Studio 2008 and Microsoft Expression Web.

In researching the type of lenses I wanted for a Nikon D80, I became increasingly frustrated by the type and quality of information available. User suggestions and ratings tended to focus on the most expensive lenses and ignored price. I had a limited budget, but wanted to know what would give me a good value for my budget.

I've summarized in this article what I believe as of October 2007 are very good quality lenses for very good value. I favor zoom lenses over a fixed focal length prime lens so I have a bias towards zooms. I also don't favor really wide angle lenses so I've not listed those.

Why These Lenses?

Caveat: Unless I own a specific lens, I didn't test it. I have researched the test results, reviews, and comments recommendations of others. All prices are listed as of October 2007. I own the D80, the Nikon 18-135mm f/3.5-5.6G. I also have some older pre-1972 Nikon lenses, but those are pre-AI lenses and do not fit the D80.

I've listed these lenses because in my opinion, they exhibit good value for the price range. If you read some of the news groups on lens recommendations, folks always recommend the $1600 lens. That's not my budget and I suspect it's not everyone else's either. I wanted to know if I spend a certain amount, what was the best value I could get for my money. That was is the primary reason I wrote this list. The second reason was people kept recommending lenses and I had no idea of the cost or quality.

I looked for good quality recommendations, popular lenses that if I decided to sell, others would want as well, and I also looked for lenses that retained their value. The Nikon lenses seem to retain their value very well. The prices of Nikon lenses on e-bay are sometimes higher than the price of a new lens. Unless I thought it was a very good value and highly recommended, I've listed only Nikon lenses.

I've listed the filter size because when buying multiple lenses, it's nice and more cost effective to have filters that fit multiple lenses.

All lenses listed below work on digital DX format Nikon D80 or D200 bodies. The G lenses do not have an aperture ring and so do not work on manual focus (Manual) Nikon bodies. Vibration Reduction (VR) will not work on manual focus cameras.

IQ in the tables below refers to the Image Quality ranking from SLR Gear. BR refers to the rating (1-5) provided by Bjørn Rørslett.

Nikon D40 D40x users: If you are considering one of these lenses, I would recommend you check the compatibility of the D40 or D40x to support auto focus on these lenses. The D4o and D40x support autofocus only on lenses with AF-S and AF-I which are equipped with an autofocus motor.

Budget of $250 or Less

Description	2007 Cost	Filter	Film	Manual	IQ	BR	Reviews
Nikon 50mm f/1.8D AF Standard Auto Focus Nikkor Lens	$109.95	52mm			9.13	5	Ken Rockwell SLR Gear Photodo Bjørn Rørslett Rating Nikon USA PhotoZone
Nikon 18mm - 55mm f/3.5-5.6G ED II AF-S DX	$114.95	52mm			7.81		Ken Rockwell SLR Gear Nikon USA PhotoZone
Nikon 55mm - 200mm f/4-5.6G ED-IF AF-S DX VR	$229.95	52mm			8.20	3.5	Ken Rockwell SLR Gear Bjørn Rørslett Rating Nikon USA PhotoZone

Budget of $500 or Less

Description	Cost	Filter	Film	Manual	IQ	Reviews
Nikon 18mm - 135mm f/3.5-5.6G ED-IF AF-S DX	$329.95	62mm			9.25	Ken Rockwell SLRgear.com Thom Hogan Nikon USA PhotoZone
Nikon 85mm f/1.8D AF	$399.95	62mm			9.50	Ken Rockwell SLR Gear Nikon USA PhotoZone
Sigma 18-50mm f/2.8 EX DC Macro	$399.95	72mm			8.83	SLR Gear PhotoZone
Nikon 70-300mm f/4.5 - 5.6G ED-IF AF-S VR	$479.00	62mm			9.13	Ken Rockwell SLR Gear Nikon Imaging Nikon USA PhotoZone
Tamron 17-50mm f/2.8 Di II LD Asperical IF SP AF	$449.95	67mm			9.14	SLR Gear PhotoZone

Budget of $900 or Less

Description	2007 Cost	Filter	Film	Manual	IQ	BR	Reviews
Nikon 18mm - 200mm f/3.5-5.6G ED IF AF-S DX VR	$769.95	72mm			8.24	4	Ken Rockwell SLR Gear Thom Hogan Bjørn Rørslett Rating Nikon USA PhotoZone
Nikon 80-200mm f/2.8D ED AF	$899.95	77mm			9.42	5	Ken Rockwell Ken Rockwell (afs) SLR Gear Nikon Imaging Bjørn Rørslett Rating Nikon USA

Budget of $1000 or More

Description	2007 Cost	Filter	Film	Manual	IQ	BR	Reviews
Nikon 17mm-55mm f/2.8G ED-IF AF-S DX Nikkor	$1199.95	77mm			9.18	4.5-5	Ken Rockwell SLR Gear Bjørn Rørslett Rating Nikon USA PhotoZone
Nikon 17mm-35mm f/2.8G ED-IF AF-S Nikkor	$1499.95	77mm			9.11	5	Ken Rockwell SLR Gear Bjørn Rørslett Rating Bjørn Rørslett Review Nikon USA
Nikon 80mm - 400mm f/4.5-5.6D ED AF VR	$1429.95	77mm			8.77	4	Ken Rockwell SLR Gear Bjørn Rørslett Rating Bjørn Rørslett Review Nikon USA PhotoZone
Nikon 28mm - 70mm f/2.8 ED-IF AF-S	$1434.95	77mm			9.6	5	Ken Rockwell SLR Gear Bjørn Rørslett Rating Nikon USA PhotoZone
Nikon 70-200mm f/2.8G AF-S VR	$1624.95	77mm			9.83	5	Ken Rockwell SLR Gear Bjørn Rørslett Rating Nikon USA PhotoZone

Other Popular Lenses

These lenses are good values, but in my opinion, not the best. I've listed them because they get recommended frequently. In the cases of the f/1.4 lenses, the similar f/1.8 lenses are better values in my opinion.

The Nikon 105mm f/2.8G ED-IF AF-S VR while recommended by some, it's not recommended by others and the older non VR version appears to be a better value. Unfortunately, it's no longer available new.

Description	2007 Cost	Filter	Film	Manual	IQ	BR	Reviews
Nikon 70mm-300mm f.4-5.6G	$134.95	62mm			7.43	3-3.5	Ken Rockwell SLR Gear Bjørn Rørslett Rating Nikon USA PhotoZone
Nikon 50mm f1.4D AF	$284.95	52mm			8.79		Ken Rockwell SLR Gear Nikon USA PhotoZone
Nikon 18mm - 70mm f/3.5-4.5G ED-IF AF-S DX Nikkor	$349.95	67mm			8.28	4	Ken Rockwell SLR Gear Nikon USA PhotoZone
Nikon 60mm f/2.8D AF Micro-Nikkor	$349.95	62mm			9.50		SLR Gear Nikon USA PhotoZone
Tamron 28-75mm f/2.8 XR Di LD-IF AF	$369.95	67mm			8.85		SLR Gear PhotoZone
Sigma 10mm-20mm f/4-5.6 EX DC AF	$499.00	77mm			8.48		Ken Rockwell SLR Gear PhotoZone
Tokina 12mm-24mm f/4.0 PRO DX AF	$499.00	77mm			8.08		Ken Rockwell SLR Gear PhotoZone
Nikon 24 - 120mm f/3.5-5.6G ED-IF AF-S VR	$514.95	72mm			8.00	3.5	Ken Rockwell SLR Gear Bjørn Rørslett Rating Nikon USA PhotoZone
Nikon 105mm f/2.8G ED-IF AF-S VR	$759.95	62mm			9.50		Ken Rockwell SLR Gear Nikon USA PhotoZone
Nikon 12mm-24mm f/4.0G ED-IF AF	$899.95	77mm			8.07	3.5-5	Ken Rockwell SLR Gear Bjørn Rørslett Rating Nikon USA PhotoZone
Nikon 85mm f/1.4D IF AF	$1024.95	77mm			10.00	5	Ken Rockwell SLR Gear Bjørn Rørslett Rating Nikon USA PhotoZone

Notes

All lenses have some trade offs. When I see a pattern of multiple reviews reporting similar symptoms for a particular lens, I've noted it below. In many instances, some users report a lens as being not sharp, but other users report it is sharp. I would trust the measured lens results at SLR Gear and the MTF published results more than the users when it comes to sharpness.

Read the lens reviews and ratings carefully. Not all lenses that are f/2.8 provide the best image quality  at f/2.8.

The Nikon 18-135mm lens has had reports of motor noise and repairs needed under warranty. I own this lens and I have personally experienced the noise problem with this lens when the lens was turned at a 90 degree angle, but it went away when turned back to the horizontal. I have not sent this lens in under any warranty repair. I am extremely happy with this lens and it's range and results.

The Nikon 105 mm VR is not recommended by Ken Rockewell due to focusing problems.

Many users of the Nikon 18-200mm have reported having the lens barrel slips when pointed down.

References

• [1] SLR Gear Nikon Zooms SLRgear.com
• [2] SLR Gear Nikon Primes SLRGear.com
• [3] What is your favorite lens? Flickr.com
• [4] What lens do you use most in photography? Flickr.com
• [5] Best of the Best Bjørn Rørslett
• [6] Nikon Lens Links

Updates

1. Nov 1, 2007 - Added Sigma 10-20, Tokina 12-24 and Nikon 12-24.