Opticallimits

Some sample images from the EF 24-70mm f/4 USM L IS

 

http://photozone.smugmug.com/Religion/canon2470f4

 

A ... difficult ... lens.

….i'm inclined to think that the designer of this lens is one who has particular tastes in photography and as such prefers to see his wide shots focused forward …. and we must obey …. 

 

…. edit 3/3 …. and one might hope, if the above is true or even if not, that the beautiful soft bg bokeh, is …. 

Guess a whole bunch of my neurons must of died during the night! What's the tease?

 

Dave's Clichés

Quote:Guess a whole bunch of my neurons must of died during the night! What's the tease?

 

Dave's Clichés

 

Well, as usual ... the sample gallery ... which always means that the review is immanent.

Well here's a tease from me,a question from University challange the other night; What's the focal length of a plain piece of glass?

Quote:Well here's a tease from me,a question from University challange the other night; What's the focal length of a plain piece of glass?

 

Because parallel light rays never intersect it has no focal length.

But Yes! The answer is infinity, official answer, although I said infinite.

 

 Going back to my school days,parallel lines meet at infinity.

I got marked down when doing physics at school as I thought about things in too much detail. I think I'm about to have one of those moments again!

I'd argue the focal length may be infinite for all practical uses, but it could be a bit less than that. If we assume the glass was perfectly parallel, it would still have mass. Mass means gravity, which would make the light converge at some point. However if we throw in dark energy that may not apply any more and things get way beyond my level!

Quote:I got marked down when doing physics at school as I thought about things in too much detail. I think I'm about to have one of those moments again!


I'd argue the focal length may be infinite for all practical uses, but it could be a bit less than that. If we assume the glass was perfectly parallel, it would still have mass. Mass means gravity, which would make the light converge at some point. However if we throw in dark energy that may not apply any more and things get way beyond my level!

 Hi,

    You shouldn't have got marked down!one should always ask questions and questions need details,I digress,I'm going to get out the bike this afternoon and check out this infinity theory:  I  may be sometime!

Quote:......I'm going to get out the bike this afternoon and check out this infinity theory:  I  may be sometime!

..... like maybe forever