I tripped over this 'ISOless' issue in some large threads recently and have found your article above to be the source material. It has given me much food for thought and practical experimentation with my Canon 6D. From sensorgen, I find the 6D to be a partial ISOless camera, ISOless from about 3,200 ISO, and have tried some experiments comparing brightened RAWs (in ACR) at 3,200 to those taken at ISO 102,800.
As you state, the noise is just the same but the gain of the ISO 102,800 setting has blown highlights when compared to the 3,200 + brightening. Note, there seems to be a considerable colour difference between the two methods, greatly reduced by also adding extra brightening to the green channel. So my tests continue with the prospect of never increasing ISO past the 3,200 setting unless the DR of the scene is low.
Thank you for the stimulating post. I will have to rethink much on the back of it. Empirical results will be my yardstick but thanks again.
My greatest debt to DPReview is for the cameras you stopped me buying with your in-depth reviews. You have saved me thousands! I am a sucker for the latest new gimmick.With deepest gratitude and best wishes to ALL at DPReview.
So near and yet so far.
Seen this review and another showing live in human hands - it is big.
If it was Full frame, same mount, 5 Fps for RAW AND HDR groups, preferably faster auto focus, and not too much dearer, I would buy it for all my old K-mount lenses.
The only advantage of the APS-C for FF capable lenses would be the smaller size but it isn't. The size is no problem as a user but would also almost do for a FF so the loss is the rest of the usable lens field in a camera whose major selling feature is the ability to mount all Pentax K lenses.
I await a Pentax FF follow-up with great anticipation. The K-01 is pointed right at the appropriate market and proved they are capable of delivering just what is needed, so let's be having it.
I hope this is just a simulation because I don't think they will ever have to make one!
Gold plated, crocodile-skinned, 35mm Leicas may well be 'gilding the lily' but where's the 'lily' here?