More questiona about the a77 and a99

Started Apr 29, 2013 | Discussions thread
Shop cameras & lenses ▾
JerryCurtis Veteran Member • Posts: 9,017
When is f/2.8 not f/2.8?

Amateur Sony Shooter wrote:

Even if they are all F2.8 lens, 70-200 at tele end will receive less light,

Please explain this statement, with references, if you would?

-- hide signature --

*Jerry*
Sony V1, H5, A350 and A77... Still learning...
'The camera is an instrument that teaches people how to see without a camera.'
-- Dorothea Lange
http://www.pbase.com/icicle50/root
http://www.pbase.com/icicle50/image/88943577/medium.jpg

 JerryCurtis's gear list:JerryCurtis's gear list
Sony Cyber-shot DSC-V1 Sony Cyber-shot DSC-H5 Sony Alpha DSLR-A350 Sony SLT-A77 Sigma 10-20mm F4-5.6 EX DC HSM +9 more
Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow