where's my sharpness? 85L + tubes.

So after hearing about the magic of the 85L on extention tubes I finally got around to going out today and getting myself the Kenko 12-20-36 tube set... funky.

That looks like movement (motion blur or camera shake) to me. I think you need to start with more light

Typical Russian winter. It probably won't be light out till next month; all the indoor lighting here sucks, and the sun is perma twilight.

i can't imagine how tiny the DOF would be at f1.6, on a FF, at 85mm with a full set of tubes on..

DreDaze wrote in post #9321650
i can't imagine how tiny the DOF would be at f1.6, on a FF, at 85mm with a full set of tubes on...stop the lens down...use a flash

Hmm, might just have to try that sometime. 20mm is the furthest I've gone so far. I'd really like a flash but that'd have to wait, they're kinda expensive here.

this is the 85/1.8 with a 12mm tube -- and 100% crop of the file

Boring winter day, so I was playing with my 85L + 25mm tube last week. Not much DOF at 1.2.

ISO-400, f/1.2, 1/80

HOSTED PHOTO
please log in to view hosted photos in full size.

What was the f-stop in the OPs shot? Looks like the DOF was around 0.02 centimeters.

RandyS wrote in post #9321717
What was the f-stop in the OPs shot? Looks like the DOF was around 0.02 centimeters.

f1.6

f/1.6 with 20mm tube. according to a dof calculator there might be less than 1mm of dof... not sure.

Edit:

So, I took up that challange (at f/1.2!) and took this picture of my 70-200 f/4 is: the "t" in stabilizer is just barely sharp, if you can call it that.

full frame

The 85L has a real distinct look with tubes, I love it. Very painterly.

I use my 85 f/1.8 from time to time to take product photos (with 1.6X crop cameras without tubes). I find that at its MFD, I'd need to use f/11 to gain about 3 inches of focus depth.

actprivate wrote in post #9322669
I use my 85 f/1.8 from time to time to take product photos (with 1.6X crop cameras without tubes). I find that at its MFD, I'd need to use f/11 to gain about 3 inches of focus depth.

Good thing then, that the 85's don't seem to become diffraction limited up to f/16

In any case, the whole point of me getting the tubes was to, as BlueTsunami put it, give photos a "painterly" effect. Gonna have a ball once spring turns around.

Kolor-Pikker wrote in post #9322905
Good thing then, that the 85's don't seem to become diffraction limited up to f/16

Ah, the DL! Honestly though I haven't noticed a problem at f/11 either with 85 or my 100 macro when using 40D or even 7D. Diffraction must be there somewhere, but I cannot see it in real life.

Kolor-Pikker wrote in post #9322905
In any case, the whole point of me getting the tubes was to, as BlueTsunami put it, give photos a "painterly" effect. Gonna have a ball once spring turns around.

Fair enough. I never thought of it this way. Good to learn a new thing every day

there are so many things that make for sharpness in tube shots....and sometimes you have to let go of the quest for tack sharpness

I do 3 shot bursts, handheld, with an Ee-S precision focusing screen and manual focusing. And even with all that sometimes its not "tack sharp"

Is this recent shot tack sharp? Dont know... Does it speak to me on an artistic level? Yes

85L and one 12mm tube at 1.2

HTTP response: 404 | MIME changed to 'text/html' | Byte size: ZERO

HTTP response: 404 | MIME changed to 'text/html' | Byte size: ZERO