06-02-10 – Macro Bugs

I have a really cheap macro for my Olympus Four Thirds. It can do 1:1, but you have to get really close to do this. However, because of the size of the sensor, 1:1 actually becomes 1:2 (so I read). Does this mean that I cannot take “true macros”, only “half-sized”?

No, whatever you read was wrong.

Magnification, in photographic terms, is purely an artifact of the lens, not the camera body. At 1:1 magnification, the image projected at the focal planes on each side of the lens is the same size.

So on a full frame camera at 1:1 you can capture 36x24mm, and for 4/3 its 17x13mm, but the magnification in both cases is the same.

I would also like to know where my pictures fit into the true, faux ,or not macro definition. I only have my 18-55 and my 55-250 lens’s and I don’t think either one is a true macro lens but they do say macro on the lens some where. Well it has the little flower that is supposed to mean macro. on the 18-55 it says .8ft for the min. focus point. on the 55-250 it’s more like 3.4 ft.

i’ll defer to sleeping on strict definitions but IMHO your “macro” lenses, like mine, are more a marketing gimmick than true macro.

i have to use extension tubes to get “true macro”. that said i have no idea how sensor size/crop factor figures into all this. in the (good) old days you could actually measure the subject and compare it to the image size on the negative. with digital — god know how you check. or for that matter what you check 🙂

All three pictures I posted were taken with the macro, but I don’t think I could get the magnification I saw in some of the posts (what I think you mean by “true macros”). To achieve that, would I need extension tubes? Longer focal length macro lenses?

here’s an interesting article on extension tubes

http://www.shutterfreaks.com/Tips/ExtensionTube.htm

and here’s a good wiki article on marco lenses and other ways to get close.

http://en.wikipedia.org/wiki/Macro_photography

god know how you check. or for that matter what you check 🙂

Photograph a ruler with a MM scale with the setup you want to know the magnification of. Compare that to your sensor size, which should be available online somewhere for most cameras 🙂

i think i hate you 🙂

i’ve done that with a ruler and my 35mm camera and it should have occurred to me. i have a 6″/153mm pocket ruler at work and will have to remember to bring it home.

thanks.

I would have a hard time holding a ruler up to that wasp but I am guessing it was around 2 centimeters or so. The google tells me my camera has a 22.2 x 14.8mm sensor. I did not crop that picture at all just sharpened it. So does that mean thats a macro picture?

you mean this one? marked 3/3
http://www.fark.com/cgi/comments.pl?IDLink=5363952#c60871414

if so then no. the wasp would have to fill the frame edge to edge right to left and yours doesn’t fill the frame top to bottom.

but yeah given my record tonight perhaps sleeping will check it and give us a ruling.

/ha ha, i said ruling

your dragon fly is better than mine and mine was shot using a 26mm extension tube.

and while i liked my fly having dinner it wasn’t as sharp as it should have been. hand holding with manual focus and using extension tubes can be really iffy.

and my jumping spider is a classic example of shallow DOF.

the big plus to the not really macro macro lenses is better DOF and more usable shots.

your dragon fly is better than mine and mine was shot using a 26mm extension tube.

and while i liked my fly having dinner it wasn’t as sharp as it should have been. hand holding with manual focus and using extension tubes can be really iffy.

and my jumping spider is a classic example of shallow DOF.

the big plus to the not really macro macro lenses is better DOF and more usable shots.

Thanks. that was taken with the 55-250 lens with the focus all the way in and me wobbling back and forth till I liked the focus if I remember correctly. Slightly cropped but not much