Crop Factor, Low Light and Aperture with m4/3 lenses? Part 2

Started 3 months ago | Discussions thread
Anders W
Forum ProPosts: 17,886Gear list
Like?
Re: Crop Factor, Low Light and Aperture with m4/3 lenses? Part 2
In reply to bobn2, 3 months ago

bobn2 wrote:

Anders W wrote:

bobn2 wrote:

Anders W wrote:

bobn2 wrote:

Anders W wrote:

Just another Canon shooter wrote:

Anders W wrote:

Just another Canon shooter wrote:

Anders W wrote:

"What is known based on the laws of optics is that if we take a lens design for a certain format, say a 50/1.8 for FF, and scale it down in all relevant dimensions so as to make 25/1.8 for MFT, the two lenses will deliver the same resolution if we measure per image diagonal (and the MFT lens twice as much as the FF lens if we measure per mm) at the same f-stop as long as resolution is limited by lens aberrations only."

There is no such thing as limited by lens aberrations only.

In optical theory there is.

No, there is not.

Yes there is.

Anders, please cite this 'optical theory'. So far as I know, there is always diffraction. How is any lens not subject to diffraction?

There is always photon noise and read noise. Does that prevent us from isolating their effect on image quality?

Change the topic, why don't you?

I hoped you might see the analogy, but apparently I was mistaken. So let me translate: The fact that certain factors are always present does not prevent us from isolating their impact.

You are still changing the topic.

I am perfectly on topic. You questioned my assertion and I explained its basis.

That might have been a sensible answer to give to JACS rather than 'in optical theory there is'. However, you chose differently. Only you know why.

I substantiate my claims to the extent that substantiation is asked for as I just did. If JACS had asked for it, I would have done him the same favor as I did you. But he didn't.

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
Post (hide subjects)Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow