DOF with Sigma 70-300 in macro mode

[christiand]

I was curious to find out some things related to macro photography with the Sigma 70-300mm APO super II.

So I set up a ruler and pointed the D70 at the 10cm mark of that ruler.
The D70 was on a tripod set to shoot from an approximate angle of 45 degrees from above.

here are the results of the quick and dirty test:

f 5.6 DOF 9.9cm to 10.7cm
f 8 DOF 9.9cm to 10.7cm
f 11 DOF 9.8cm to 10.8cm
f 16 DOF 9.7cm to 11.1cm
f 18 i must have bumped the D70, no conclusive results
f 22 DOF 9.5cm to 11.3cm
f 32 DOF 9cm to 11.5cm


Regards
CD

[digitor]

Was this at 300mm focal length? I've only had a limited bash with mine on macro, http://www.pixspot.com/displayimage.php?album=78&pos=3 but it seems the DOF is not great, this flower is about 10mm in diameter. The shot was at 300mm, f8.

Cheers

Edit: Got the aperture wrong, it was f8

[christiand]

yes, these tests were done at 300mm
and also at minimal distance to the ruler.
(couldn't get any closer)
I believe that you connot get a larg DOF when doing macro.

now have a look at this one:
http://www.pixspot.com/displayimage.php ... 4&pos=-425

this was shot at 195mm, f10 and it has enough DOF.

HTH
CD

[christiand]

question for digitor:

were you using a tripod ?
what were the D70 settings ?

Cheers
CD

[digitor]

yes, these tests were done at 300mm
and also at minimal distance to the ruler.
(couldn't get any closer)
I believe that you connot get a larg DOF when doing macro.

now have a look at this one:
http://www.pixspot.com/displayimage.php ... 4&pos=-425

this was shot at 195mm, f10 and it has enough DOF.

HTH
CD

Nice shot! Yes, it has enough DOF all right. The macro on the Sigma is only available from 200-300mm though, so maybe this shot was taken in "normal" mode? I'm not really sure what the macro selector does on the lens, but it enables a closer focus distance, and limits the focal length between 200 and 300mm.

Cheers

[digitor]

question for digitor:

were you using a tripod ?
what were the D70 settings ?

Cheers
CD

Tripod, remote control, old flash on hotshoe in manual mode, 2 sheets of A4 paper for reflectors, 1/80 sec shutter speed (for some reason, don't ask me why, probably some vain attempt to add some room lighting to the mix), flash w/b.

Cheers