exposure time

[Unregistered]

Hi.

I don't know where to put these questions so I put them here.

My questions are:

1) In the specs, the longest exposure time for the DMX 640x480 series cameras is 0.3 sec. Is there any way (including hacking the software/hardware) to prolong the exposure time beyond that to a minute or more?

2) The specs says the sensitivity of the monochrome camera is 0.8 lux at 1/30 sec. Does it mean that the sensitivity will be 0.4 lux at 1/15, 0.2 lux at 1/7.5 secs and so on?

3) The shutter speeds are 1/3.3 to 1/30 seconds. What are the steps in between that?

4) For the product DMM21F04, what is the thread size for the lens mount?

Thanks for your help!

[Stefan Geissler]

Hello



1) In the specs, the longest exposure time for the DMX 640x480 series cameras is 0.3 sec. Is there any way (including hacking the software/hardware) to prolong the exposure time beyond that to a minute or more?

No, there is no way to prolong the exposure time.


2) The specs says the sensitivity of the monochrome camera is 0.8 lux at 1/30 sec. Does it mean that the sensitivity will be 0.4 lux at 1/15, 0.2 lux at 1/7.5 secs and so on?

I do think, the sensitivity behaves nearly but not absolute linear in relation to the exposur time.


3) The shutter speeds are 1/3.3 to 1/30 seconds. What are the steps in between that?

This depends on the settings type. If you set the exposure in physical units, you have following exposure times
1/2048 seconds
1/1024 seconds
1/512 seconds
1/256 seconds
1/128 seconds
1/64 seconds
1/32 seconds

If you set the exposure times as register values, there are 511 steps between 1/3300 and 1/30 seconds.



4)For the product DMM21F04, what is the thread size for the lens mount?

The DMM 21F04 has the same front panel as the DMK 21F04, so the same lenses can be used.