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I'm still getting fairly inconsistant shots with this wide open. At F2 its great, and very sharp and perfect contrast but at F1.2 its very difficult to get the focus bang on and sharp even with the EE-S screen installed.

Here is a shot at F1.2 on Wall Street, New York.

Full size, statue head as focus point. Manual focus. Seem ok?

Can anyone help me with some kind of chart perhaps that shows Depth of Field on a full frame sensor at certain lengths?

http://members.iinet.net.au/~teamkk/5D/_MG_85L.jpg

used this a while ago http://www.silverlight.co.uk/resources/dof_calc.html

actually thats not the one but it does help, ill try to find the other one

here it is http://www.dofmaster.com/dofjs.html has actual body names, also this is handy http://www.dofmaster.com/doftable.html they have a printable version which is about the size of a small hand

Thanks Michael! only issue is it goes down to F1.4 and not F1.2

Edit: pwhoar. At F1.2 and 1.5meters away, theres like 3cm of dof

Kris, I don't see any issue with that shot. Also don't forget that Canons tend to be a tad softer so run it through an USM filter as well. If you're shooting at f1.2 and the focus point was on the head, the DOF would be quite shallow.

hats the amount of sharpness you get at widest aperture

1.2 will never be tact sharp compared to rsults when stopped down to f8

ive used the 1.2 on a 5d and markII same results but on portraiture softness is more subjective

Thanks guys. I was reaaaaaaaaally far away for that test shot. I figure the dof was alot larger when so far back. Like you guys have said, stopped down will be sharper but I brought this lens for really wide apertures so sharpness at F1.2 to F2 needs to be stellar to justify its cost.

I think this copy is good. Considering I've not applied any USM. Just need to keep the dof issues in mind and have a steady hand

michael_ wrote:here it is http://www.dofmaster.com/dofjs.html has actual body names, also this is handy http://www.dofmaster.com/doftable.html they have a printable version which is about the size of a small hand

This is a cool reference Michael, and it tells me why I am having so much trouble getting confident with my new 70-200 F2.8 Canon lens eg at 200mm and F2.8 the depth of field is razor thin. However, that's how I like it with the amazing bokeh from the lens etc which you can't get at smaller apertures.

Kris, when you're shooting at f1.2 to f2 shouldn't really be expecting razor sharpness when you consider DOF. If you don't want it, give it to me.

Piro, It should be! Thats what $3k in glass should do (well I think so)

The DoF may be very very very very small, but it should be razor sharp. I think the statue is quite sharp considering @ 100% and wide open. Its just trying to get all my F1.2 shots that sharp. At F2, the success rate is much much higher and I can use AF

Gavins site has some great info

http://www.gavincato.com/lenses/Canon%2085mm%201.2.html

And although it may be obvious, it is worth remembering that when you are shooting wide open,
the depth of field is exactly as you see it through the lens. I know it can be difficult to judge at
the time (our brains are incredibly good at making adjustments), but it is something to consider.

Kris,

Greg and Gavin's site has clarified what I was saying earlier With those photos taken at 1.2 on Gavin's site, look at where the focal point is and look at the other elements in the photo. Apply USM and do slight curve adjustments to pull up the contrast and she will be tack sharp.

Ill try this and apply some USM to see how I go. Might do some focus tests now I'm home to make sure its all good!

Thx!