K20D dynamic range at ISO100

I read somewhere recently a piece which implied the K20d has better dynamic range when shooting at ISO200 rather than ISO100. Is this true and if so would shooting at ISO400 give even more improvement?

I'd be interested to see that piece. Generally speaking, dynamic range reduces the further you get from "base" or "natural" iso. The piece you read may have inferred that the k20d's "base" iso is 200 rather than 100.

iso400 would give you less dynamic range.

this link would indicate that iso100 has most dynamic range on the k20d, although how they measured this I am unsure. But strangely on the next page where they review the D-range expansion option they have this statement.

The K20D offers a dynamic range exansion option, which appears to adapt the applied tone curve to retain highlights better (at the expense of noise in the shadows). Enabling D-Range doesn't appear to change the exposure yet is only available from ISO 200 upwards which suggests the sensor's native sensitivity may be ISO 200, hence offering slightly improved dynamic range at that setting.

Hi RR

Thanks for the reply. I just can't remember where I read the original statement. I think it was a side comment in a forum or blog piece. I find online I read something then whizz on to the next piece and after 10 or so sites (maybe more) I can't remember what I read where.

I've just searched for more info. A few sites think ISO200 may be native on the K20d but no one seems to know for sure. Maybe their just repeating info from the review you linked to...

One really interesting fact. It appears that a little extra dynamic range can be squeezed out of RAW files when using ACR if custom conversion parameters are used rather than the default. This was from the same DPReview article.

I read this relating to a K100d, Scroll down about a third in "tips and tricks,

http://www.pentaxforums.com/forums/pentax-dslr-articles/37711-k100d-tips-tricks....