10 stop ND filters and infrared

Hi there - a question for the techies!

I'm considering buying one of those nd filters in order to get really long exposure times. However, they are said to do really bad on cmos sensors. Reason for this seems to be cmos sensors sensitivity to infrared light.

I'm pretty sure I will be buying a k5 soon. Should I keep (and bring with me) my old GX10 for long exposures? That camera is not sensitive to infrared light - as I sadly discovered when I recently bought one of those infrared filters.

What to we know about the k5 sensor - I suppose it has an infrared cut off filter but is it as strong as the GX10/K10? Any pentaxians with relevant experiences to share?

CCD is also sensitives for infrared.
It's that the K10D or the GX10 has a filter in front of the sensor that blocks infrared but it's still sensitive for IR though.
I've read the filter in the K5 stops less IR but i don't see a reason why that would be bad for your sensor and why that would be a reason no to use an ND?

All I can tell you so far is that the K-r seems more sensitive to IR than the K10D or K20D. The results of "pseudo-IR" done in Photoshop are rather good.

Well, as far as I understand the ccd powered gx10 could do alright for long exposures. But if Stefan is are right about the K5 then the problem should be pictures with a heavy colour cast because too much infrared light hits the sensor.

On the other hand, the gx10 in my experience is no good for infrared photography, where as the K5 might be usable.

Yeah, I have played a bit with pseudo-IR in photoshop and I'll probably just stick to that - unless the K5 turns out to be usable in that regard.

It seems that Hightech have the most problems.
I believe some UV filter actually cut all the light outside the visual spectrum so also IR, maybe that will help.