what magnification is this?

[petedam]

Hey folks! If I have my 100mm attached to 12mm+20mm+36mm....and zoomed all the way in what magnification am I getting?

Thanks in advance!

[malcolm027]

What 100mm lens? I think your DOF would be super thin though.

[petedam]

What 100mm lens? I think your DOF would be super thin though.
Cannon 100mm. I usually shoot at f11.

[John_B]

petedam,
Its 2:1 (2x times life size).
Look here Macro Variations <-- click to see (http://photography-on-the.net/forum/showthread.php?t=578274) where I show pictures of a ruler to show the magnification with different setups.

PS. I am assuming you mean the 100mm macro lens, right? ??? ;)

[petedam]

John_B
yes it's Canon 100mm macro.;)

Thanks for the link. I do ok with the 100mm and the 68mm extension tube but when i add the 50 mm reverse.....i find it very difficult. with the 100mm and the reverse 50mm 1.4 set up what should one should @ (f number)?

thanks again!

[John_B]

petedam,
Yes I also find it difficult and very rarely use that combination but only because I have the MP-E 65mm f/2.8 which goes up to 5x. However the reversed 50mm f/1.4 mounted to the 100mm f/2.8 does give sharp macro results to my eyes but very little working room for lighting the subject.

My suggestion is play with the setup and find what you are comfortable with. The 50mm is set at f/1.4 but you still control the aperture of the 100mm. :)
Using the tubes with the above is even that much harder to get light to the subject ;)

[petedam]

Thank you John_B!