85 1.8 vs 85 1.2

[neuroanatomist]

Focused on one given spot with my 85 1.2 @ 1.2 = 1/125. Then bumped up to 1.8 = 1/60.


I'll let the brains figure out the decimals. I know it something over 1 stop. Obviously the 85 1.8 may expose differently.

Realizing the 1/125 and 1/60 may skew the numbers, I tried a scenario where 1.2 was 1/320 and then 1.8 turned out to be 1/160.

Thanks, Keith. So at least for that lens, it's a 'complete' stop. 1/320→ 1/160 and 1/125→ 1/60 areboth one-stop changes in shutter speed. Each stop represents a rough (but not necessarily exact!) doubling/halving of the amount of light. The full-stop scale is 1, 1/2, 1/4, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000, etc. Underlined jumps are not exact divisions by 2. Your first example just happened to fall on one of those.

[Cozen]

Focused on one given spot with my 85 1.2 @ 1.2 = 1/125. Then bumped up to 1.8 = 1/60.


I'll let the brains figure out the decimals. I know it something over 1 stop. Obviously the 85 1.8 may expose differently.
<div style="clear: both;"]</div>

Realizing the 1/125 and 1/60 may skew the numbers, I tried a scenario where 1.2 was 1/320 and then 1.8 turned out to be 1/160.
<div style="clear: both;"]</div>

<div style="clear: both;"]</div>





This is nice to know. That is a pretty big difference. A $1500 difference? Hard to say =P

[peety3]

http://the-digital-picture.com/Pictures/Picture.aspx?Picture=2006-04-29_19-21-38


http://the-digital-picture.com/Pictures/Picture.aspx?Picture=2004-04-17_11-09-19


Honestly, if you're looking for an 85 prime, you probably have a reason to get one. If so, that reason should lead you to the right lens. If not, your wallet should lead you to the right lens. They really are two totally different animals. If you don't know what you want/need, get the 85/1.8. It'll work very well for everything you ask it to do.