Dynamic Range -- what it is, what it's good for, and how much you 'need'

Started Oct 17, 2011 | Discussions thread
Great Bustard
Forum ProPosts: 23,179
Like?
Re: Hilarious!
In reply to FrankyM, Oct 23, 2011

FrankyM wrote:

Great Bustard wrote:

FrankyM wrote:

You are assuming that read noise scales with pixel area.

I am not "assuming" -- I am defining "equally efficient sensors" as two sensors with the same QE, same read noise / area, and same saturation limit / area.

Yes, you are defining a situation designed to give you the answer you want.

What is the "answer that I want", and what's my agenda for wanting that answer? That smaller pixels, for equally efficient sensors, always result in greater IQ?

But if you really want to make a comparison between large and small pixels you should start with a level playing field. Read noise, for a given manufacturing process, simply does not scale with pixel area. Therefore, your definition is comparing apple with oranges.

What is this "level playing field"? Here -- you may find this discussion relevant:

http://forums.dpreview.com/forums/read.asp?forum=1032&message=39651584

AFAIK, for a given manufacturing process this is not the case. If you are referring to different manufacturing processes then we are comparing apples and oranges.

It's funny because I just addressed all that in my post above:

http://forums.dpreview.com/forums/read.asp?forum=1022&message=39661473

The reality is far more complex than simple scaling. All I'm saying is that "equally efficient sensors" means the same QE and that per-pixel read noise and saturation limit scale with pixel area throughout the ISO range.

That said, some sensors are pretty close -- e.g. the 5D2 and E5. I mean, they're so close, one might even think that Olympus copied the 5D2 sensor and just scaled it down.

Sorry, I hadn't seen the above post. But it doesn't really answer my question.

What was your question? How read noise varies with pixel size in the real world? Depends on the specific cameras being compared:

http://www.sensorgen.info/

Reply   Reply with quote   Complain
Post (hide subjects)Posted by
MathNew
You.New
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow