F-Stop explained.

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F-Stop explained.

Postby gstark on Wed Apr 04, 2012 8:23 am

This is very informative. Highly recommended.

http://www.gizmodo.com.au/2012/04/what- ... otography/
g.
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Re: F-Stop explained.

Postby Mr Darcy on Wed Apr 04, 2012 11:22 am

This is quite superb Gary. Thank you
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Re: F-Stop explained.

Postby Chaase on Wed Apr 04, 2012 6:03 pm

It's when I watch videos like this I realise how little my Doveton Tech School education taught me :(
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Re: F-Stop explained.

Postby Reschsmooth on Wed Apr 04, 2012 7:59 pm

F-stops? I was hoping for a video on G-strings
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Re: F-Stop explained.

Postby Remorhaz on Wed Apr 04, 2012 8:50 pm

I reckon it was all great except for the last ten seconds...
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Re: F-Stop explained.

Postby Steffen on Wed Apr 04, 2012 10:55 pm

What was wrong with the last ten seconds?

That said, I would have preferred if he had used square millimetres when referring to areas rather than millimetres.

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Re: F-Stop explained.

Postby Remorhaz on Thu Apr 05, 2012 7:36 am

[quote="Steffen"]What was wrong with the last ten seconds?[/quote]

He started mentioning that the visual aperture size as viewed through the lens is not the "actual" aperture size and doesn't match the calculated aperture size from the f-stop (i.e. a new topic/concept) but unlike the rest of the video where he describes in very clear detail how it works and why he just leaves this at that with no explanation...
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Re: F-Stop explained.

Postby Steffen on Thu Apr 05, 2012 12:52 pm

That is actually correct. The aperture that results from applying the f-stop ratio to the focal length is in fact the diameter of the entry pupil, i.e. of the virtual image of the iris. It is not (generally) the physical diameter of the iris. Hence, with a 300mm f/4 lens, the aperture (75mm) is the diameter of the virtual image of the iris, as seen through the front of the lens. It is (obviously) not the size of the iris, the whole iris assembly is smaller than that.

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F-Stop explained.

Postby ATJ on Thu Apr 05, 2012 2:39 pm

Stefan, I don't Rodney is questioning the accuracy but rather the idea of throwing that in at the end of the video and confusing viewers.
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Re: F-Stop explained.

Postby Remorhaz on Thu Apr 05, 2012 3:15 pm

[quote="ATJ"]Stefan, I don't Rodney is questioning the accuracy but rather the idea of throwing that in at the end of the video and confusing viewers.[/quote]

Correct - I'd rather he didn't mention it at all or spent another minute explaining it :)
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Re: F-Stop explained.

Postby Reschsmooth on Thu Apr 05, 2012 4:25 pm

[quote="Remorhaz"][quote="ATJ"]Stefan, I don't Rodney is questioning the accuracy but rather the idea of throwing that in at the end of the video and confusing viewers.[/quote]

Correct - I'd rather he didn't mention it at all or spent another minute explaining it :)[/quote]

Wasn't he saying he was going to cover it in a future video? Therefore, this would have acted as a teaser to that?
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Re: F-Stop explained.

Postby Steffen on Thu Apr 05, 2012 5:00 pm

Yes, I was about to say, good way of building up interest in the next episode :)
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Re: F-Stop explained.

Postby surenj on Sat Apr 07, 2012 2:07 am

Nice one!

Very illuminating.
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Re: F-Stop explained.

Postby Reschsmooth on Sat Apr 07, 2012 8:00 am

[quote="surenj"]Nice one!

Very illuminating.[/quote]

One could say 'eye opening'
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Re: F-Stop explained.

Postby stubbsy on Sat Apr 07, 2012 3:37 pm

Thanks Gary - well explained and easy to follow.

The same person has a few more:

Depth of Field explained

ISO explained
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