Hi guys,

i’ve gotten the lasers from aixiz(rated 780nm 25mW) and they work fine at 4.2 v and i’m using the firefly camera. no worries i had my googles on when working on them.

the blobs are bright and clear without the IR bandpass filter. however, i had a problem when i put a exposed negative over the lens, i get feint blobs. do i really need those commercial IR bandpass filter? if so, at what rating should i get?

and also when i use the ROI feature from the Firefly to get 320 by 240, the captured image is darker than the 640 by 480, is it normal?

The exposed negative is not the best filter. Its good for a tempory measure, to test stuff.  I would recomend buying a IR band pass filter that is 780nm in wavelength.  This means it will only let through 780nm give or take 10nm depending on the manufacturer.  I got mine from Knight optics, but if you google band pass filters youl find a supplier.

icube - 13 August 2008 08:59 AM

also when i use the ROI feature from the Firefly to get 320 by 240, the captured image is darker than the 640 by 480, is it normal?

The reason why the blobs are dimmer is the faster capture frame rate. By increasing the shutter time your image will get brighter, but this will compromise your capture frame rate. The trick is to find the optimal setting for your application.

~Alex