Kodak 8300 chip RGB imaging times with astronomik T2 filters.

[RobH]

I've been doing some rooting around, and have found this information.. Hopefully it might be of use to some of us.

Obviously, the imaging times take no account of atmospheric refraction or LP issues.

Cheers

Rob

KODAK 8300 sensitivity with Astronomik type 2 filters.

Red. 44%

Green 53%

Blue. 47%

If Green is 100%

Red 83%

Blue. 88%

Red exposures therefore need to be 17% longer than green

Blue exposures need to be 12% longer than green.

For 600s green, red should be 702s, blue 672s.

For 600s Red, green should be 498s, blue 516s

[Catanonia]

Ah nice that would explain the green images I get with the QHY9

[dmahon]

If Green is 100%

Red 83%

Blue. 88%

Red exposures therefore need to be 17% longer than green

Blue exposures need to be 12% longer than green.

For 600s green, red should be 702s, blue 672s.

For 600s Red, green should be 498s, blue 516s

For equivalent exposures, I'd have thought you needed a 20.5% increase in red (120.5% of 83 is 100) and a 13.6% increase in blue (113.6% of 88 is 100).

green = 600s

red = 600s / 83 * 100 = 723s

blue = 600s / 88 * 100 = 682s

[dmahon]

Having different imaging times screws with your darks though, you need to take 3 times as many! Can't you just alter the percentages as you combine them?

[shaunster]

Having different imaging times screws with your darks though, you need to take 3 times as many! Can't you just alter the percentages as you combine them?

Yep maxim allows you do to this, not sure on other programs