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Here's an article on Canon DLC RE: "back-button autofocus explained".
http://www.learn.usa.canon.com/resources/articles/2011/backbutton_af_article.shtml
<p><strong>Canon’s patent</strong></p>
<li>When doubled, twice the lateral aberration, longitudinal aberration is 4 times greater rate of expansion, because the F-number is also double, longitudinal aberration is twice per depth of focus</li>
I read that as it, like the 2X, adds two stops. So a 2.8 lens -> 5.6, not 8.
you've read wrong: you loose 2 stops with the 1.4 converter, and tree stops with the 2.0 .
this means 4 stops with the 2.8
I'm sorry you're not right - you loose 1 stop with 1.4 and two stops with 2.0. Assume you have 400mm f4. It means a hole is 100mm wide (400/100). If you add 1.4 TC, you have 560mm. So it becomes 560/100 = f5.6 and f4 -> f5.6 = 1 stop. Calculate it with TC 2.0 and TC2.8 accordingly and you will find it.
yeap, you're right.
sorry
I love how you fight about "stops" dudes ... bit of a clue : take F/2,8 or F/4,0 or whatever indeed and just multiply by the number on the extender ... magic
Wow, how did you do that? That's really a case for Penn & Teller
<p><strong>Canon’s patent</strong></p>
<li>When doubled, twice the lateral aberration, longitudinal aberration is 4 times greater rate of expansion, because the F-number is also double, longitudinal aberration is twice per depth of focus</li>
I read that as it, like the 2X, adds two stops. So a 2.8 lens -> 5.6, not 8.
you've read wrong: you loose 2 stops with the 1.4 converter, and tree stops with the 2.0 .
this means 4 stops with the 2.8
I'm sorry you're not right - you loose 1 stop with 1.4 and two stops with 2.0. Assume you have 400mm f4. It means a hole is 100mm wide (400/100). If you add 1.4 TC, you have 560mm. So it becomes 560/100 = f5.6 and f4 -> f5.6 = 1 stop. Calculate it with TC 2.0 and TC2.8 accordingly and you will find it.
<p><strong>Canon’s patent</strong></p>
<li>When doubled, twice the lateral aberration, longitudinal aberration is 4 times greater rate of expansion, because the F-number is also double, longitudinal aberration is twice per depth of focus</li>
I read that as it, like the 2X, adds two stops. So a 2.8 lens -> 5.6, not 8.
C. Fn 2, Custom Controls, set the first option (shutter button) to either "Metering Start" or "AE Lock".
This was among the very first things I did to the 5D3 when it arrived. The whole point of back-button focus is to separate the focusing from the shutter activation. The AE Lock (on shutter half-press) is handy when shooting Av/Tv because you can focus on one point, meter on another, recompose, and activate the shutter independently. Total control.
Edit: I just saw how Canon chose to abbreviate the setting name.. "Shutter Butt. half-press". Really, Canon? There's no other way to abbreviate "button"?
Very happy after several years of waiting but why did they not put in a rotating back display???
according to this video and cr guy , it seems they are pretty confident about the 5D3 release..lets wait 2 more days ..
http://www.phototips.biz/2012/02/phototips-canonrumors-live-cast.html
from the website -
"..I believe their will be a special feature of this camera that has the potential to change our industry.."
absolutely NO mention is made about the sensor' size in the specs.
Could very well be the 7D II.
Anyone think the same?
absolutely NO mention of it being a camera in the specs. Could very well be a waffle maker.
Anyone think the same?
