A650 IS KAP Parameters

I did some more ground-level experimentation with my A650 at lunch yesterday. This, in conjunction with my testing from last week and this week, can be summarized:

• The A650 IS can do ground-level IR photography, but under sunny-16 conditions, I'm getting 1/6 second exposures. Without modifying the camera to remove the IR blocking filter, I won't be doing any aerial IR photography with it. I have a Hoya R72 infrared filter on order.
  
• The A650 IS has some UV response as well, which I tested through a Schott UG-1 filter. Unfortunately this filter also has a big IR leak which I can't readily filter down. Without further testing I'm not willing to shell out the money for a UV bandpass filter. (These are not cheap.)
• The A650 IS works remarkably well at altitude. Because of the long focal lengths involved, a wide-open aperture works fine. The optics on the A650 IS can handle this without introducing unacceptable optical aberrations.
• At the shutter speeds I can get during the day, I don't think image stabilization is helping all that much. This is still an open question since I haven't tested it in the air, of course, but ground testing supports this. I do think IS will help me shoot in lower light, though, so sunset and night-time KAP may be an option whereas it wasn't with the Coolpix 5600.

The daytime shots I used to build the vertical panorama in my last post were at 1/640 sec shutter, wide-open aperture, and ISO 80. I can't really improve on that. The shots as they came off the camera were a little "hot", though. On the Coolpix I used -2/3 EV exposure compensation. From ground shots yesterday, I think a similar exposure compensation would work well on the A650 IS as well.

So here's the final setup I'll be using for my upcoming tests with the AuRiCo controller:

• Shutter Priority Mode (Tv)
  
• Exposure set to 1/640 seconds
• -2/3 EV exposure compensation
• ISO floats, clamped at ISO 200 (this is normal for the camera)
• Aperture floats, no limits

I still need to tune the timing parameters on the AuRiCo to make sure I get the image overlap I need in order to stitch. That will happen today or tomorrow during lunch, if the weather holds.

I'm still waiting on some bits for my camera, namely the Hoya infrared filter and the 58mm adapter tube. Once these are in I get to start playing with one other fun item: I've never hoisted a circular polarizer onto an aerial camera. I wonder how the reef would look with no sky reflection at all!

Tom