Should I just by an extension tube set?.

Sheesh. YES. Save yourself the trouble, headaches, time, and money. A tube is not that expensive..

Thanks,.

Greg.

Tim'Be the change you wish to see in the world.' -Mahatma Gandhihttp://www.flickr.com/photos/timskis6/..

A reversed lens macro setup can work well for close work. Here's an example:.

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The reverse lens is 55mm which corresponds to about 18 Diopter. The polyethylene cone was cut from a funnel; it was cut so the top opening was the right size to screw into the reversed len's filter threads..

Reverse lenses are great for high magnification close-up work. This is because the working distance is constant, 35mm for old film camera lenses..

A lens for a 35mm camera is constructed so the distance from the rear of the lens to the film plane is 35mm when the lens is focused at infinity. This means the subject should be 35mm from the rear of the reversed lens - the camera lens then looks backwards thru the reversed lens & sees the subject as if it were at infinity..

The reversed lens should have a large aperture to avoid vignetting..

The constant working distance of 35 mm gives sufficient room for illumination of the sample and allows one to make a simple support system for the lens/camera..

All of the images of George Washington were taken just by setting the plastic cone over a dollar bill..

It is almost impossible to hand hold the camera for macros at these magnifications because the depth of field is extremely small: also if extension tubes or front mount diopter lenses are used the working distance is so small that it is hard to light the sample..

The above setup worked well for me so I added a Nikon SL-1 Ring light to the lens (I cut a hole in an old rear-lens cap & glued it to the ring light to support the lens.).

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A reversing ring was put on the reversed lens so the whole setup screws directly to my camera lens..

Such an elaborate setup isn't needed for lower mag close-up work. I don't use it for corrections of 10 diopters or less..

Dave.

PS Diopters= 1000mm/Lens_focal_length..

Questions:.

"For the lens mounted reverse, what is best to use? I good old manual focus, fast prime? What range is good? How do you control the aperture on this outer lens? Do you need a lens that you can manually set it to wide open?".

Answers:Best lens to use? - old manual focus fast prime.What range is good? - depends on magnification you want but I think 35-70mm.How to control aperture? - jam it open if need be..

After good success with an old manual 55mm prime I decided a 35-80mm zoom would be great. I bought one & it didn't work well because it was f/3.5-5.6 & the vignetting was too bad. Get a low f-stop prime or zoom..

Dave..

Get the widest aperture 50 mm lens that has the aperture blades wide open when not mounted. You should be able to pick up a 50 mm f/1.8, or even better a f/1.4 for less than $50. Look for a multicoated Pentax or Olympus if you can find one. Camera stores often have draws full of 50 mm lenses..

50 mm lenses usually have a 52 mm thread, so you will need a 52 mm to whatever-your-other-lens-is coupling ring. The best thing to mount it on is something like a 28-135 mm zoom. Set the reversed lens to infinity and use the zoom on the camera mounted lens for focusing..

Extension tubes are best used on moderate angle, fixed focal length lenses. They work great on 50, 85, and 100 mm lenses. The longer the focal length, the less effect they have. A set of Kenko tubes on a 50 mm lens will get you well beyond 1:1..

There is really nothing to beat the experience of a dedicated macro lens. Any other means you use (extension tubes, supplemental close up lenses, reversed lens. bellows) will severely restrict the focusing range..

Brian A...

Hugowolf wrote:.

Get the widest aperture 50 mm lens that has the aperture blades wideopen when not mounted. You should be able to pick up a 50 mm f/1.8,or even better a f/1.4 for less than $50. Look for a multicoatedPentax or Olympus if you can find one. Camera stores often have drawsfull of 50 mm lenses..

50 mm lenses usually have a 52 mm thread, so you will need a 52 mm towhatever-your-other-lens-is coupling ring. The best thing to mount iton is something like a 28-135 mm zoom. Set the reversed lens toinfinity and use the zoom on the camera mounted lens for focusing..

Extension tubes are best used on moderate angle, fixed focal lengthlenses. They work great on 50, 85, and 100 mm lenses. The longer thefocal length, the less effect they have. A set of Kenko tubes on a 50mm lens will get you well beyond 1:1..

There is really nothing to beat the experience of a dedicated macrolens. Any other means you use (extension tubes, supplemental close uplenses, reversed lens. bellows) will severely restrict the focusingrange..

Brian A..

You can buy an adapter for $20 or $30 dollars that screws onto the end of your lens, and allows a direct mounting on the camera..

From then on, everything is manual. The shorter the focal lenght, the greater the magnification..

You can set whatever aperture you want, which will increase the DOF, the tradeoff being that you are in a permenent state of "previewing" the image, meaning at f16, everything will appear very dark..

You can only focus by moving the camera..

What are the advantages?.

The advantages are profound. The claritiy of the images will be much greater than using the lens normally. Greater then any other possible set-up. Properly used, you get better clarity then the most expensive Macro lens, or any other possible combination of tubes..

Personally I found that a 55mm lens is about all I needed. Shooting with a 35mm produces HUGE magnification..

But after practice, I had no problem shooting handheld..

Dave..

Chato (Dave) must be right & I'm wrong. Reversed lens aperture shouldn't matter (except for brightness & depth of field.).

Dave..

Thanks for the good replies... I know for ease, a dedicated macro lens will do the trick more often than not, but.... I do want to try this out, and appreciate all the quality feedback that is based on experience....

Thanks again everyone....

- Greg..