Where does the 2 sec limit come from ?
Sorry to grave dig an ancient comment / thread, but just figured something out with this that might help future people.
I had my Faxitron MX-20 working well for years on Win XP, bur recently replaced with a "new" Win 7 32-bit machine to run other various old stuff here (The Faxitron included).
After a full clean install of the Faxitron software I was running up against issues with it not allowing any exposure of 2 secs + failing to calibrate (needs a 3.5sec exposure).
I figured out this maximum exposure limit comes from a registry key.
You can change it to any value you want
The default the DCAM API installs is 2, so I changed it to 20, (as the Faxitron software works up to 19 sec I recall).
HKEY_LOCAL_MACHINE\SOFTWARE\Hamamatsu\DCAM\Modules\husb2\device
And edit whichever sensor / camera you have.
In my case I changed the C9732DK string from
FPS:EXP(1,2) to
FPS:EXP(1,20) and everything magically started working.
I don't know what the upper limit to this value is.
I used:
Windows 7 32-bit
DCAM API 13.10.4418
Faxitron SR 1.6
Sensor: C9732DK (12cm sensor)
(I believe DCAM API 13 to 19 will work for Win 7, but I'm unsure where it breaks down with Faxitron 1.6. V13 definitely works great on Win 7 and XP.)
Maybe I installed things out of order and the Faxitron software changes this registry key? Who knows, but hopefully this post will help any future Faxitron MX-20 users.
All the best,
Dan