Publications Update

23 11 2010

If you click on the publications tab at the top of this blog you will see I have updated the links with my ASOR paper and presentation on the Middle Bronze Age at Tall Safut and my book review of Eric Meyers Festschrift to be published in the upcoming NEASB.

Pottery! At Last!

23 10 2010

Apologies for not posting more regularly, life has been quite busy. Bill Dever was here for a few days last week, so that took up some time and of course I’ve been hard at work on the dissertation.  My main focus over the last several weeks has been twofold, first making sure I have everything digitized so I can write while I’m in Jordan, and second getting the gui interface running smoothly.  Finally I have conquered the program and finished drawing all of my Middle Bronze Age pottery.  Just in time because I only have a month to write that chapter and prepare my ASOR paper based on it.  As a sneak preview, and to demonstrate the wonders of the program. I put together a plate of my MB bowls.

You can ignore the scale, because I had to downsize it for the blog.  I’ve been working on parallels, and the most helpful volume so far has been “The chronology of the Jordan Valley during the Middle and Late Bronze Ages : Pella, Tell Abu Al-Kharaz, and Tell Deir ʻAlla” edited by Peter Fischer.

3D Scanning Part 3: The End Result

18 09 2010

This picture shows the end result of the 3D scanning process, the sherd profile drawing.  On the left is a visual representation of all the profiles throughout the sherd, with the bluish colored dots at the bottom representing places where the sherd was broken.  On the left is the final drawing with sherd properly stanced and radius calculated.  This sherd dates to the end of the Middle Bronze Age, around 1450 BCE.  It was found in Area D, which was a section cut into the side of the tell next to the road, in order to determine whether an artificial glacis (or rampart) existed (more on this in the coming months, since this is the main topic of my ASOR conference paper).  Unfortunately Area D, along with half of Area A, is no longer with us, cut away by bulldozers expanding the main N-S highway from Amman to Jerash.

This illustration shows another benefit of basing the final drawing on a 3D scan, the ability to depict the sherd in three dimensions (seems obvious).  The gui interface was programmed to display side and top 3D views of the sherd, adding a nice touch to the traditional sherd profile drawing.  This bowl dates to the end of the Iron Age (the 6th century BCE) and was found in Area A.  It was excavated from a room directly inside the city wall, which was expanded at the end of the Iron IIB.

3D Scanning Part 2: Oh Sweet Irony

16 09 2010

The irony is that my second post on scanning has been postponed because of issues with the 3D scanning.  There have been several issues that have come up in the last few days.  We had ordered more attachments for the scanner so we can scan 3 or 4 sherds at once.  They arrived in the mail at the beginning of week, so Jacob and I had to go to the hardware store to by more parts to make our own attachment clips.  The arrival of the attachments was very exciting because it will greatly speed up the scanning process.  Unfortunately soon after we got the attachments ready the turntable stopped turning.  Earlier in the day the turntable was having some issues, but we got it working again.  Now it was dead, not moving at all, after trying a few different things I got on the nextengine chat.  The technician I talked to suggested a few things but nothing was working.  We were resigned to buying a new one (around $200), however two hours later students came in to scan and it was working again.

So one big issue avoided for the time being, the second issue involves the pottery program created by Avshalom Kerasik from the Weizmann Institute.  A little explanation is needed to get to this point (the purpose of this post in the first place).

After finishing a 3D scan, the scan file must be opened in a second program called Meshlab, which is an open source program for processing and editing 3D files.  We then have to open the adjusted file in a gui interface created by Avshalom, compiled from another program called Matlab.  The gui interface essentially takes the best average of all profiles through the entire sherd.  So instead of cutting a sherd and drawing one profile (which is all drawing by hand or using photoshop could do), you get a 100% accurate representation of the sherd.  The program also calculates the stance of the sherd and the radius automatically, so no guess work is required.

The second problem, which I referred to above, is that I can’t get this gui interface to work.  A number of different problems and solutions have been suggested, each sound quite promising, but so far I can’t create any drawings.  The other day it was suggested  I install Matlab and we were to a point where I was confident it would work, but still no luck.  Hopefully this program will be working soon, because I’m ready to work on the Middle Bronze, Late Bronze, and Iron I chapters of my dissertation.

3D Scanning Part 1

13 09 2010

A large part of my dissertation is based on the pottery excavated from Safut, specifically the diagnostic sherds I have in my possession here at Andrews University.  Without these 100’s (1000’s ?) of sherds I wouldn’t have a dissertation, and I had to determine the best way to draw all of them.  The old school way of drawing sherds is to cut the sherd in half using a wet saw, then trace the profile using pencil, and eventually ink it.  Of course there were more steps along the way including determining radius of the sherd and its stance.  One of our MPP colleagues, Bob Bates, developed a way of drawing the sherds using a flatbed scanner and adobe photoshop.  This process is somewhat involved but created very nice looking sherd drawings.  Unfortunately one must still cut the sherd in order to scan its profile and there is still some guess work when creating the drawing in photoshop, determining the radius, and stancing the sherd.

A few years ago at the annual meetings of the American Society for Oriental Research in San Diego I heard a paper by Neil Smith of UCSD, discussing various technologies they were incorporating into the Edomite Lowlands Project.  One of these technologies was a 3D scanner and computer program that would convert the scanned sherd image into a nice drawing.  I was immediately fascinated and talked with Neil after about the logistics of the process, cost of the machine, etc.  I convinced my professors of the importance of this technology and began emailing Neil and Avshalom Kerasik who had developed this whole process at the Weizmann Institute in Israel.

A little over a year after hearing the original paper by Neil, we purchased a NextEngine 3D Scanner.  This machine costs around $4,000 including software, which is a fraction of the cost of most scanners of comparable quality.  This post is getting long, so tomorrow I’ll explain how we get a pottery drawing from the 3D scan, and why it is so much better than the old way of drawing sherds.