1) Where do I need to start?
One good place to check is my sourceforge project page.
On that site i keep all the code, revision history, build instructions, parts list, etc.
2) Are there any prerequisites for starting this project?
You need to be able to use some basic tools. There are some parts that have to be made such as the machined out bracket set. We use a plastic called Lexan which is incredibly tough and nearly indestructable, other people have made thier owb brackets out of acrylic, wood, and even metal. For those who are not able to build thier own brackets my machinist does offer kits indlucing all the custom parts(motor mount, end backed, carriage top, spacers, backlash nut bracket) for $220.00. As for the controller i have instructions on the sourceforge site listed above on how to build one step by step, wire by wire. To simplify things we also offer ChronoShields which make the controller assembly far easier. It is a PCB that contains the display, controls, inputs, outputs, etc that plugs onto an Arduino. We also offer 100% completed controllers as well. We really try to make sure this is something anybody can do. If you go with a bracket set and a ChronoShield, all that is left is a little bit of soldering and assembly. You will need to be able to drill through 2 bolts (any drill press will work, just go slow), and you will have to tap the rail ends with a 3/16th tap ($10 part, takes about 5 minutes, very simple). Then solder on the DB9 connection for the motor and limit switches, run those wires, solder them to the limit switches, then just a few nuts and bolts.
3) Where can I buy all the gear?
Check the Wiki on the sourceforge page.
On here is a list of parts with links to the places you can purchase them.
4) When there's a stepper motor involved in this project, can I get the code to implement this stepper mortor? If so, where can I get the code and how can I program that stepper motor with that code?
The stepper is controlled by the Chronos 2.0 software. It is a work in progress, i added some new features recently but the debugging is pretty much done. I have a new version i plan to upload which will enable people to calibrate the controller to work for various applications without having to dive into the code. That should be up in the next week or so as Chronos 2.1
The code is also on sourceforge.
Look for CHRONOS_2_0_MASTER_FILE_FOR_SOURCEFORGE.ino in the Chronos 2.0 Schematics and Code sub folder.
Download that file, then when the controller is finished you will need to upload that code to the arduino. Go to arduino.cc and download the Arduino 1.01 IDE for your operating system. Then once you have that installed and the drivers are updated you plug the arduino into the computer with the correct USB cable, load up that file you downloaded into the Arduino IDE program, and hit the upload button. Then you will be using the latest version of Chronos 2.0 (or 2.1 when it is finsihed).
5) How much does it cost in total?
Total cost if you do EVERYTHING yourself, make your own brackets, build your own control box etc, i would estimate to be around $500 depending on cost of shipping, part selection, etc. If you want brackets made that is + 220, if you want a controller built it adds about another $150 to the total cost.
If you so desire we can build you a complete system that includes the control box, rail, adjustable feet, battery, and camera cables for $1,200 US (pricing subject to change so check with us to be sure)
6) I know that you have improved this product over time. You are already in Chronos 2.0 version, so do I need to build the earlier version or can I directly build Chronos 2.0 version?
Start directly with Chronos 2.0
Chronos 2.0 is in the final stages of completion. I had a wish list of things i wanted to accomoplish with the code that was not finished when people started building. The code took a brief period where there were a bunch of bugs introduced, but to my knowledge they have all been wrapped up. The final version of the code allows you to calibrate with the controller to work with other setups such as a belt drive, or a different lead-screw by allowing you to save in a new rail length and steps per cm (chronos does its own internal metric to standard conversion) and it also allows you to swap the motor direction and swap the limit switches in case the wiring is reversed and such. My goal is to have the new final finished code published by Dec 25 2012. After that there will be no more additions or modifications except to fix any bugs that may arise. I believe there is still information on Chronos 1.0, but i would not recommend wasting your time with it. Chronos 1.0 was my first attempt at this, it was a pretty basic system and more of a hardware prototype for Chronos 2.0. The only real hardware change from 1.0 to 2.0 was the indrotuction of the LED display and about 5-10 dollars worth of extra electronics parts. However whereas Chronos 1.0 was a basic system capable of basic routines Chronos 2.0 is a fully featured time lapse system that easily holds its own against professional systems that cost thousands of dollars.
7) is this fast enough for Video?
Not with the lead-screw configuration. If you opt to go with a belt design and use the ChronoContoller to control it then yes video speeds should be obtainable, at the sacrifice of the movement accuract needed to do macro timelapse.