This is an elaboration of the standard
long exposure mod which now gives the pc control over
individual interlaced frame downloads (self-guide), on
chip amp and shutter disable.
The charge transfer pluses into pins 8 and
13 of the d15201 control image retrieval from lines
.. and 3,4,7,8,11,12
respectively This feature has the potential to be used
for self guiding the webam. Basically one frame is
downloaded at a fast rate (1-5 sec) and any drift
countered by the pc sending guiding commands to the
telescope mount. The second frame is exposed for much
longer (up to 20 min or so). This has the potential to
allow very deep exposures. The pictures below give an
example of the frames being read at different rates.
On Chip Amp.
The sony ccd uses a small pre-amp to increase the video
signal before it leaves the ccd. The problem with this is
the electro luminescence that it gives off. See below
The mods require that the signal to pin 10 of the d15210
(shutter pluse) is disabled during a long exposure. This
is conveniently achieved using a simple switch. However
this mod give the option of controlling it at the pc.
Who will find the mod useful?
Probably many fewer people than use the standard mod!
This version is aimed at allowing very long exposure
pictures. In addition to the modified camera you will
also need a telescope and mount capable of taking guiding
instructions. Without this the self guide feature will
not be useful. Also if exposures are kept to below 30 sec
or so standard dark frame subtraction can be used to
remove the amp glow. However if you do have a
computerised scope then this camera has a very great
The novel information on these pages is copyright. It is forbidden to
use this information for profit. Should you receive any money as a
result of performing this mod or selling a modified camera send the
money (less parts) to www.msf.org.
Over the last year I have received some requests from people who are
looking for a way round these restrictions. I would like to take this
opportunity to specifically state that it not OK to give modified
cameras away free with other products nor is it OK to charge people for
you time when going mods for others.
Any individuals of companies wishing to produce
commercial products based on these modifications please contact me
directly firstname.lastname@example.org .
Please abide by these restrictions, as this will ensure that future
developments can disclosed in the same way.