Alex, Thanks for all the info. I have not come across any of the programmes / methods / equipment that people use apart from the basic video cameras, so this discussion has been very useful in that respect. I know it is old school, I appear to be about 20 years behind, but a tutorial article for the BAA would be great and perhaps persuade more people to take up this great method for visual astronomy which can contribute valuable science if one perseveres.
I looked up the MAX7456 used in the VTI equipment and found it is obsolete from Maxim but there is a Chinese copy. It just makes it harder to enter the field with a piece of equipment as it will require a software development using the sync pulse edge. The Arduino addon uses (used!) the Maxim chip, ok for end user / developers but not for a product.
Thanks again for all the valuable info.
Cheers
Alan