so since i have been using my macro lens (which i am stil in love with!) i have been dabbling with greater than 1:1 magnification. i have done a lot of research into the various ways to this. close up diopters, extension tubes, reversed lenses, bellows, teleconverters, etc.
it can be pretty overwhelming and confusing sometimes! As you may remember, before i got the macro lens, i was using a reversed 50mm 1.8d on my camera to achieve 1:1 magnification. albeit at the sacrifice of all the automatic functions of the camera, and working distance! but it worked and was a lot cheaper than a macro lens!
well, now that i can go to 1:1 with all the auto functions and a little over a foot of working distance, i wanted to experiment with more than life size! i spend awhile researching methods to do this and decided on using a combination of a reversed lens and extension tubes. well, i don't actually have the extension tubes, but i am able to reverse my 50mm on the end of my 105mm macro for roughly 3x life size (as far as i am concerned)
I went this route because it seemed to be the cheapest (teleconverters are pricey), have the best image quality (diopters can have a degrading effect on IQ, extension tubes have no optical elements, the nikkor 50mm f1.8 is a quality lens), and have the most potential for portability (try handholding your camera with a bellows attached to it!)
what i wanted for this to work:
-a 52mm to 62mm male-male coupling ring to thread onto the front of the 105mm (62mm filter thread) and the front of the 50mm (52mm filter thread) so i can attach them together.
-this leaves the rear element of the 50mm exposed at the front of your rig, so i was trying to think of ways to DIY a cover for the end of the 50mm involving a rear lens cap that i was going to cut the center out of and MacGyver a UV filter on the end. but i wanted instant (relatively) gratification, so i did some poking around online and found that nikon of all people make something specifically for this!! the Nikon BR-3 has a fitting to attach to the rear part of your lens, and then it has a 52mm filter threading on the other end so you can attach a filter over it, thus protecting the sensitive bits of your reversed lens! i found one on ebay pretty cheap and it works great, although it does cut down your working distance a smidge (more on that later)
-then i just used my flash bracket i made up a while ago (see older posts) and made a soda can diffuser thanks to lordV at dgrin (directions here)
so i was setup. here is a shot of this monstrosity i have created (it will be bigger when the extension tubes come around :) )
if you click and go to the flickr page, look at the full size and you can see the BR-3 on the front with the filter on it protecting the rear element!
well, now its time to take some shots to test it out!
first of, a shot of the millimeter markings on a ruler.
so there is about 8mm shown across the whole frame. so according to the internet ;) to determine magnification by photographing the millimeter markings on a ruler, you; divide the width of the sensor of your camera by the amount of millimeters in your test photo!
so sensor width of a nikon DX dslr is 23.6mm, divide that by 8mm and you get 2.95! so just shy of 3x lifesize :D cool! lets find a bug or something
off i go to the backyard to go crawl around in the grass! here is a little sampling of what i found:
this is one of those dandelion puffballs. the brown stalks are the stems of the actual white wispy parts that fly through the air, and the holes are empty spots where the wispy things used to be (very scientific i know)
Here is the same dandelion, from a different angle, really showing off the detail of the wispy parts stems (i need to figure out what they call those things)
there seems to be a theme here! this is a different dandelion, this one with all its wispy's intact. and covered in water droplets!
Sorry about all the dandelions, we dont really have much of a garden, so all we have is an abundance of dandelions :)
Finally a little creature to capture. i found this fellow enjoying a meal on the bricks of our house.
see a 100% crop here to see the details of the eyes, its amazing!
So, a little on depth of field (how much of the image is sharp). the above images were shot with an aperture of f/16. for landscapes and such, that would usually suffice to render a large part of the image sharp. but at this magnification, its not good enough most of the time, especially when shooting bugs. for the most part, you should attempt to get the insects eyes in focus, unless you are accentuating a particular portion of the body. i managed to do this in the spider image, but you lose the rest of the detail because of the lack of depth of field.
so, to combat this, i am trying to perfect my skills of 'focus stacking'. this is taking multiple exposures of the same shot, but each shot focusing a little farther into the image. you then take all these exposures and you combine them in a program like helicon focus, combine zm, or zerene stacker. the dandelion wispy water droplets picture above is a focus stack of about 3 or 4 frames. i only have a trial version of helicon focus, but it seems to give the best results. combine zm is good and free, but the final stacked image is only 96dpi, which is unfortunate because free stuff is always better :). zerene stacker i just heard of, downloaded it (its still in beta), but i wasnt too pleased with the results, i was probably using it wrong, i am going to try again in the next little while.
**edit** i forgot to talk a bit about working distance! with the normal macro lens, it will focus at about 12 inches in front of the lens at life size magnification. with the reversed lens on the front, i have about 1-2 inches give or take (have not taken an official measurement yet!), and with just the reversed 50mm directly on the camera body, its pretty similar, a few inches. so, for shooting bugs with the macro lens and reversed lens combo, you have to be reeeeeeeeaaaal slow in your approach. i suggest practicing with a non living object, moving in and out of focus so that you get a feel for where that sweet spot is! and as always, although it takes a bit of practice, i suggest manual focus the majority of the time! then you can focus the shot by moving swaying your body back and forth slowly and hitting the shutter at the precise moment you are in focus (of course :) ). i am going to use some electrical tape and tape my cable release to the flash bracket next time i go out and that will probably help out too. also i am going to experiment with mirror lockup, any tiny movement can throw your focus off by a lot!
and, don't get frustrated!! i have a ton of images i have deleted because the focus was off by a hair (literally). it takes a lot of practice, i am still perfecting my technique and am nowhere near as good as i want to be :)
alright, so i didnt intend to type so much, but i guess i get excited when talking about this kind of stuff because its so fun and i still get blown away when i look at a shot of a tiny bug that takes up my whole computer monitor and seeing all the insane details :)
well, thats it for now! i hope this was informative and helpful to anyone wondering about increasing magnification beyond life size! if you have any questions or comments, feel free to drop me a line!
i will leave you with a cool shot i took a few days ago, called 'i heart you'