Archive for December, 2010

Merry Christmas and a Happy New Year

Monday, December 20th, 2010


At the end of the 2010 I would like to take the opportunity to wish all my readers a Merry Christmas and a Happy New Year. 

Looking back to 2010, it was clear that the economy was recovering.  I think that most of us had a great year in imaging.  I do hear many people telling me how busy they were in 2010 and how good their business was over the last 12 months.

If I look to my own activities, 2010 started with a successful International Solid-State Circuits Conference or ISSCC.  After a dramatic edition of 2009 (with strong reduction of participant numbers due to the economic situation), the 2010 edition partly recovered.  The number of attendees was not up to the record level of a few years ago, but the negative trend turned into a positive one !  Being the Chair of the International Technical Program Committee (ITPC), my responsibility was to put together the technical program.  Of course that is something I was not doing on my own, I got a lot of help of the subcommittee chairs and all technical committee members.  It was quite a bit of work, but it was also a great experience.  For me, the highlight of the conference was the plenary session.  First of all, this was the opening session of the ISSCC and I had the honor chairing the plenary session.  Talking in front of 3000 people gives goose bumps, I can assure.  But once the plenary session was finished, the conference ran (so to say) by itself.  Amazing how such a huge organization with 5 parallel sessions autonomously proceeded.  A lot of very important work is done behind the curtains, without these efforts the conference could never be that successful.  Thanks to all people involved in the ISSCC2010, it was a great experience working with you and I learned a lot from it !

More conferences were not attended in 2010, but I did visit the Photokina in Cologne and the Vision in Stuttgart (both are not so far away from my home).  It was amazing to see how Photokina evolved over the last 2 editions.  In 2008 Agfa, Fuji and Kodak, all three still had their own big hall where they exhibited their film business.  In the 2010 edition, all three exhibition halls were completely empty.  The film industry is completely gone.  On the other hand, there were a lot of electronic companies present that were not there in earlier editions.  It was clearly visible : the complete photography business has gone digital. 

My last visit to the Vision was at least 5 years ago, and actually I have to admit that the 2010 edition was a positive surprise to me.  The Vision really looks like an image capturing exhibition and that is my own playground.  It was quite funny to meet a lot of people at the booths of the various companies, but also while walking through the aisles many familiar faces showed up.  It is also surprising to me that many people recognized me because they followed one or more of my courses, but unfortunately in many cases I did not recognized them.  I would like to apologize for that, but over the last years I have had too many participants in my classes to recognize all of them or to remember all those faces.

As far as the Harvest Imaging teaching activities were concerned, the trend of recovering started already in the second half of 2009, and continued in the first half of 2010.  Several in-house as well as public courses could be organized.  The highlight of my teaching activities was the very first edition of my new course based on the hands-on evaluation of imagers and cameras.  I think it will not be a surprise to you if I tell you that I do like teaching very much, but the preparation of a new course is also very motivating.  “Teaching is learning twice” and that is fully correct.  The preparation of new course material forces me to think everything over and over again before I can put the material onto the sheets and present it in the courses.  The teaching and training will continue in 2011, and I plan to run the hands-on evaluation course at least two times in the coming year.  I am curious to see whether the participants will remain that enthusiastic about the course.  

I wish all of you the very best for 2011, and hope that we will regularly “meet” through this blog.  Thanks for visiting the website of Harvest Imaging, see you next year 😉

Albert, 20-12-2010.




What is next after the PTC discussion ?

Sunday, December 12th, 2010

Over the last months I posted a lot of material w.r.t. the photon transfer curve, and the impact of various noise sources on the PTC.  After several blogs “in dark”, also the situation “with light” was studied. But in principle, the series about the PTC is now finished.  Then the question can be asked : “And what’s next ?”   In the early days of the blog, I got several comments on the material posted.  But over the last couple of months I hardly got any reactions.  So I do not know what “my customers” would like to see being discussed on the blog.  For that reason I am writing this post.  I am searching for subjects to talk about, write about and publish on this blog.  I would like to do another series of publications on a particular subject, but what kind of subject ?

A while ago, I got an interesting suggestion : post and discuss design errors ever made in imaging.  I would not pretend that I never made any design error, but also for this subject I would like to get input from others.  Is anyone willing to share his/her mistakes that others can learn from ?  If yes, they are utmost welcome.  If you want I can discuss and post them without any reference.  So the world-wide imaging community will never know where the errors came from. 

I am curious to see whether this request for suggestions, subjects, topics can start a new series of posts on my blog.  Looking forward to it !

Albert, 12-12-2010.

First Course “Hand-On Evaluation of Image Sensors”

Sunday, December 5th, 2010

Two weeks ago I taught for the very first time the new course “Hands-On Evaluation of Image Sensors”.  The course location was Barcelona, and the organization was done by CEI-Europe.  Teaching a new course for the very first time is always a bit an adventure, because you do not know what the participants expect from it.  But this time it was even trickier,  a complete new course and for the very first time with measurement equipment in the class room.  I organized 10 laptops, 10 cameras, 10 light sources, 10 power supplies, testcharts, lightboxes, etc., all needed to perform hands-on evaluation of image sensors and cameras.   Fortunately the day before the course start I had a day off, so I had plenty of time to install the equipment in the class room and check out the hardware and software.  To be prepared for any further hardware disaster while running the course, my daughter Kim was standby during the two days, she has more experience with hardware and a soldering iron than I have myself.  But besides some minor issues, the hardware worked smoothly.  The soldering iron could remain in the travel case.

Day 1 : after a short introduction, I went through a first exercise together with all the participants.  The assignment was to proof that the noise in images is decreasing after averaging several images and show experimentally that the noise reduction is inverse proportional to the square root out of the number of images.  By itself a simple exercise to get acquainted with the equipment, to get familiar with the measurement software and to get a first idea about the difference between temporal noise (non-correlated in the images) and fixed-pattern noise (correlated in the images).

After this first getting-acquainted exercise I put all the participants to work in groups of two.  Their first assignment was to measure all fixed-pattern noise components of an unknown imager in an unknown camera by grabbing and analyzing images in dark.  Once the images were stored on the hard-drive, a short piece of code needed to be developed to calculate all parameters from the images obtained.  Some participants struggled a bit with writing the software, but after all I was surprised how quickly everyone was able to grab the images.  At the moment all groups obtained their results, the theory behind the exercise was explained and the parameters measured/calculated were discussed and compared.

Next measurement assignment focused on obtaining the temporal noise parameters of the image sensor and the camera based on the same set of images obtained earlier.  The same way of working was followed : first all groups worked separately and afterwards the results were discussed in a plenary session.

Day 2 : while the first day was focusing on doing measurements in dark, during the second day the lights were turned on.  Again in two sessions the fixed-pattern noise components were measured/calculated and later all temporal components were evaluated.  All these measurements were done quite quickly, because the code developed on the first day could be reused during the second day.  Measurements with light on the sensors at different exposure times gave rise to the famous “Photon Transfer Curve”.  All participants could experience how you can construct the PTC based on data obtained from multiple images.  But during the theoretical session it was also explained how you can generate a PTC based on just three images, on only two images and even a single image.  At the end of day 2 attention was paid on how to measure the MTF of a camera (based on a single image !) as well as on how to measure the spectral response of a camera (based on a single image !)

The overall feedback of the participants after the course was quite positive.  Several reactions sounded like : “I have learned a lot !”.  It is always good to hear that my “customers” are satisfied, but nevertheless after the first time running this course, I learned also a lot and will start to fine-tune the course for the next time.  What is going to change ?  Here is a list of action items I defined for myself :

          Some extra software functions/tools will be developed that can be used during the measurements/calculation so that the participants can focus more on the interpretation of the data,

          Extra images will be grabbed and stored on the laptops so that once the participants have the measurement code ready, it can be used for more different situations than the ones possible/available in the class room.  For instance images generated by other type of cameras, or images generated at lower or higher temperatures,

          Updating and optimizing the course material, this is always necessary after the first edition of a course.  Based on the questions and remarks from the participants during the course, I learned about the quality of my own sheets. 

Although I did already during the evaluation of the course, I would like to thank the participants once again for the cooperation during the course, for their feedback afterwards and especially for attending this very first edition of the “Hands-On Evaluation” course.  As far as I know this is a unique project in the world of imaging.  No one else organizes classes with hands-on measurements and evaluation of commercially available cameras.  It was also a very unique experience preparing this training and running it for the first time.  The updating of the course towards the second edition will take quite a bit of work, but nevertheless I am looking forward to do it.  The next “Hands-On Evaluation” course is scheduled for May 2011 in Copenhagen.

Albert, 05-12-2010.