Hi, I was thinking about the 22 bit A/D converter and about the ISO setting last night.
Then it struck me, right into the back of my head... :-) It is simply ingenious (if this is what Pentax has done): 1) By utilizing a 22 bit A/D you get a wide dynamic range 2) When you have a wide dynamic range on the A/D converter, you don't have to use a high gain amplifier stage (to get high ISO sensitivity) but you can use a constant (lower) gain low noise (optimized) amplifier. 3) This way you can "choose" the ISO setting after exposure, before storing the image into the raw (or converting to jpg). You can analyze the data and then decide "how to actually expose". I think this is what Pentax may be doing with the "automatic ISO setting". It's like having all the different ISO negative films in your camera the same time. (Of course you can have a variable gain amp if you wish to get "standard" DSLR behaviour...) 5) With a relatively low gain amplifier and 22 bit A/D (and both having low noise) you will get a really wide exposure latitude. The K10D differs from the competition in this respect. It is like how negative film differs from slide film. In theory you will get a very nice package. We'll see how it will perform in reality, but I am sure it will do quite nicely. Pentax wouldn't have used a 22 bits A/D if there wasn't a good reason. Antti-Pekka ________________________________________ Antti-Pekka Virjonen Computec Oy R&D Turku Fiskarsinkatu 7 D FIN-20750 Turku Finland Puh. +358 20 7908 300 GSM +358 500 789 753 Telefax +358 20 7908 319 Y-tunnus 1974184-5 Kotipaikka Helsinki www.computec.fi -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
