Exotic Macro Beyond 1:1

I've just read an article on some techniques for doing strange things with lenses to take them beyond 1:1 and I was wondering if anyone had tried any of this underwater (or topside) and howe well it works. What is the best way to get high magnification in underwater shots?

These ideas look like fun to try on digital because they are all not terribly expensive and you get the results right away to see if its working.

Some of the wacky ideas:

(some may be dificult to house but might be fun on land nonetheless)

1) Adding diopters. I tried adding #1 and #2 (and 1+2) diopters to my 105mm and it gave some pretty impressive magnification. I plan to get some of the higher powered 3T-6T diopters to see what they can do underwater. This looks like an easy way to get high magnification underwater.

2) Adding teleconverters. This is probably the most expensive option here but it seems like a pretty simple way to get a higher focal length and increased magnification a decent working lengths. With this option you can even (maybe) use camera metering and autofocus? Nikon has manual focus and autofocus teleconverters. With the AF teleconverters you can only use them on AF-S lenses? So I would need the MF teleconverter for the 105mm?

3) Adding extension tubes or Bellows. This looks like a simple way to get something for nothing, extension tubes are cheap and they don't reduce aperture (or quality according to the Nikon School guy?). They shouldn't be too hard to house. Which extension tubes do you need with a modern body and AF lenses? I assume its only MF and no metering with these? For really wild magnification how about a bellows? Anyone used one of these underwater? Might be hard to house.

4) Reverse mount lenses. What is this all about? How does this work? Do you use wide angle lenses like the 24mm, or telephoto lenses like the 85mm? I assume this is only MF with no metering? The rings only cost $20 so I'll try it! This should be easy to house in existing ports.

5) Stacked lenses. How does this work? What combinations are good for macro? Do you set the aperture and focus on both lenses or just the first one? Anyone tried this underwater?

Thanks for the help. This all seems strange and cool to me.

I think this will get you 2:1 or 3:1 with the wet lens not shown.. Nikon 105 with 1.4 TC.. Inon wet lens goes on ring flash...if you need more...

http://www.wetpixel.com/PNphpBB2-viewtopic...-start-15.phtml

M.

Starbuck's technique is exotic !

The techniques you mention are not so exotic and used all around, option 4 & 5 can be a little problematic in the water.

Diopters are easy and effective but they help more with longer lenses than shorter ones. Careful about power designations. Nikon's numbers have nothing to do with power. The 3T and 5T are +1.5 while the 4T and 6T are +2.9. Canon offers a 500D which is +2.

Extension tubes work like diopters. Sometimes they offer better quality and sometimes not. They are not easy to house compared to diopters though and do not work well with zooms.

Teleconverters introduce some image degradation and make the lens longer and slower. There's no substitute for this, though, when you need high power. It's better if you can afford it to use a macro lens of the desired focal length and add converters only when you need to. Yes, you rely more on diopters when you do that but your rig becomes specialized anyway. As Alex said in another thread, extreme macro is something you dedicate a dive to. You can't expect to shoot fish portraits and 2:1 on the same dive with the same rig.

The other techniques are for extreme macro. You'll be surprised how hard it can be to shoot just 3:1. Going well beyond that is extremely specialized yet you can do it with just teleconverters and diopters. A Sigma 150, a 3x converter and diopters will get you over 5:1 on a full frame camera and you can go longer!

A 105mm with a1.4x converter on a DX sensor camera can yield an apparent magnification (with diopters) of about 2.5:1, maybe better. That's a lot of power. No need to go bigger unless you really know you need to.

Oh, and I've used Starbuck's rig on a Nexus before only not with the ring flash. Works well and yeilds about 3.5:1. I like the 200mm better or the 105mm with the 1.4x converter. With a good, modular port system like the Nexus teleconverters are easy to use.

Thanks for posting your rig Starbuck. I've seen it before but its still impressive. Do you have any shots to show with it?

How do you like this rig? Is it too much magification? (Then again can anything ever be too much?) Do you find yourself not using itb very often? Why did you go for a teleconverter rather than an extension tube? What do you think about diopters on the lens rather than the port?

Craig: Maybe I got the wrong diopters then? I bought the no1 and no2 because they came in a set cheaper than the 3/4T or 5/6T. Which one(s) do I want for the 105mm? I'm committed to Alex's statement about dedicated gear for a single dive.

If extension tubes sometimes improve quality and teleconverters always degrade it (1.5-2 stop loss) then why choose expensive teleconverters? Point taken about higher power lenses (70-180 or sigma 150mm or Nikon 200mm) but these still give ~1:1 and would still require add-ons to go beyond. They just might give you better working distance.

Thanks for the advice. Sounds like from your experience teleconverters and diopters are still the way to go.

Hi -

I went with the 1.4 TC after reading all the comparisons on wetpixel and the fact that Nexus had a system ready to go for this arrangement. Multiport that will allow autofocus or manual focus on the same dive. The TC will allow greater working distance than diopter as well. The Inon wetlens is a +3 diopter that screws into middle of ring flash...decreases working distance but magnification is tremendous. I agree with Craig...not sure if the additonal diopter is necessary.

Pictures will be forthcoming.. This is my wife's rig and the lack of strobe arms and small housing make this an easy "point and shoot" setup for macro for her..

I should have something up in 2 weeks. Will be in Socorro..not necessarily macro heaven but I'll find something out there.. as long as those damn mantas aren't too distracting...

m.

Craig: Maybe I got the wrong diopters then? I bought the no1 and no2 because they came in a set cheaper than the 3/4T or 5/6T. Which one(s) do I want for the 105mm? I'm committed to Alex's statement about dedicated gear for a single dive.  

The Nikon 3T (1.5 diopter) and NIkon 4T (2.9 diopter) are threaded for 52mm (105mm), and the 5T and 6T (1.5 and 2.9 diopters) fit 62mm threads (60mm)

Karl

An extension tube gives your lens myopia, while a teleconvertor gives your lens a set of binoculars to look through...

When you put an extension tube on a lens, you are moving the potential points of focus closer to you. You can not focus at infinity when there is an extension tube present, but the lens can focus closer than it could otherwise (just as myopic people, like me, can focus extremely close when we aren't using our corrective lenses).

This is a commmon technique with ultratelephoto lenses to get closer focusing, say if you are shooting sparrow sized birds with a 500mm f4, the Nikon version of that lens has closest focus at about 15 feet (IIRC), by adding 25-50 mm of extension, the lens can be focused at more like 6 feet.

The canon 50mm macro lens uses an extension tube to get to 1:1. It is ~25mm extension, because the lens itself incorporates 25mm of extension in the mount/focusing gears. 25+25mm gives 50mm extension from the imaging plane, which gives 1:1

The teleconvertor optically magnifies the central component of the image from the prime lens, in the case of the 2x teleconvertors the central 50% of the image is magnified to fill the whole frame. In the process you are adding additional air/glass interfaces into the optical path, which results in reduced contrast and greater tendency to flare.

For some reason, the Canon lifesize converter for the 50mm that I tried in the past acted very strangely. I expected it to act like an extension tube on the Nikonos, but instead it had glass elements. It did not bring the close focus closer as I expected it would, but instead acted just like a teleconverter.

Either I am not remembering correctly, I got a weird lifesize converter that was in fact a teleconverter, or I am just insane...

Cheers

James

... Either I am not remembering correctly, I got a weird lifesize converter that was in fact a teleconverter, or I am just insane...

ahh, the insanity plea is always good out ;-)

As Karl said, the 3T and 4T are what you want for the 105mm. Personally I'd only use the 3T but I'd have it on for most dives.

Extension tubes perform a lot like diopters. They alter the range of focus bringing the minimum focus closer in exchange for the loss of infinite focus (which you typically don't need). Extension tubes also alter focal length, but basically your magnification improves because you can get closer; not for any other reason. That's why diopters aren't useful with the 60mm BTW.

Teleconverters offer a fixed magnification, typically 1.4x or 2x, and do not alter focusing range. The best you can hope for with diopters on a 105mm is less than 1.4x, so you can say that (assuming a 105mm) teleconverters offer better magnification than diopters while preserving focusing range. You can combine teleconverters with diopters, of course. The downside is that any softness in the lens is magnified along with everything else. It's well known that teleconverters degrade image quality but few seem to understand that it has to be that way. That's why you are better off using a 150mm straight up than a 105 with a 1.4x converter. Of course there are other considerations and the 105 + 1.4x is an excellent performer.

The Nikon 3T (1.5 diopter) and NIkon 4T (2.9 diopter) are threaded for 52mm (105mm), and the 5T and 6T (1.5 and 2.9 diopters) fit 62mm threads (60mm)

Ok, the no1 and no2 that I have (both 52mm thread for the 105mm) are 1.5x and 3x respectively. What is the difference between this and the 3T and 4T which are both 52mm thread as well and 1.5x and 2.9x respectively?

Why would Nikon make both?

Not certain what you have but it's likely they're single element, +1 and +2 diopters. For this application you are better off with two element, or achromat, diopters. The are much thicker physically and much more costly but they offer better performance than the single element ones. For wide angle it's not as important but for macro you want the two element ones.

Extension tubes perform a lot like diopters.  They alter the range of focus bringing the minimum focus closer in exchange for the loss of infinite focus (which you typically don't need).  Extension tubes also alter focal length, but basically your magnification improves because you can get closer; not for any other reason.  That's why diopters aren't useful with the 60mm BTW.

I don't see how an extension tube changes the focal length of the lens. All it does is move the lens, whatever focal length it is, further away from the image plane and bring into focus subjects closer to the lens. The issue with using a tube is that you are operating the lens outside of it designed range. The people who designed it may not have ever considered what the image looks like with the lens elements that far from the image plane.

That's why you are better off using a 150mm straight up than a 105 with a 1.4x converter.  Of course there are other considerations and the 105 + 1.4x is an excellent performer.

If you had both a 150mm and a 105mm that focus to 1:1 . Adding a 1.4x converter will give you a 147mm lens that focus to 1.4:1 at the cost of one stop of light and some softness as Craig pointed out. You'll have to add a diopter to the 150mm to get down to 1.4:1. I've used a Sigma 105 with a 1.4x converter with good results. For extreme macro, the softness due to the 1.4x magnification is probably less than that due to diffraction from using small apertures to get good DOF. Lossing one stop of light for focusing is undesirable.

Not certain what you have but it's likely they're single element, +1 and +2 diopters.

Craig--you are right. Appearently the ones I have are the single element veriety. I'll exchange them for the 3/4T versions.

For more info look here:

http://www.earthboundlight.com/phototips/c...p-diopters.html

Thanks very much.

The diffraction is multiplied by 1.4x also. It's true that the longer lens will require diopters to focus close, but I believe the rig is already dedicated to extreme macro at that point so adding a diopter is not a big penalty IMO. You'll probably want the same diopter on either lens setup.

It's my understanding that an extension tube alters the effective focal length of a lens. In any event, extension tubes do work somewhat differently and result frequently in more magnification than diopters do at the same working distance (but diopters reduce focal length). The right length of extension tube to use is a function of focal length so they're harder to set up. With diopters you only need to consider power and thread diameter. Plus, they're easier to house and work with zooms.

The close up lens from Nikon with a "T" are called Doublet lens and are corrected for abberation much better than the single element, another case of what you get for what you pay. the 6T power of 2.9, by the way, is also perfect for wide angle lenses or zoom wich cannot focus close enough for an 8" dome. Canon makes double elements close up lenses in 72mm and 77mm size I believe. and there is no need to disinfect your Nikon if you use a Canon Close up lens on it :wink:

Cheers

I forgot to mention Kenko manufactures extension tubes and teleconverters for Nikon and Canon autofocus system. The tubes are quite good, the extender have different amount of lenses in the formula, just make shure you get the most element (7 elements for the 2X & 5 for the 1.4X)

http://www.thkphoto.com/products/kenko/slrc-04.html

http://www.thkphoto.com/products/kenko/slrc-01b.html

Regards

The diffraction is multiplied by 1.4x also.  

Yes. That's part of the package. If you set the 105mm with a 1.4x converter at F/16, you'll have the light of a 147mm lens set at F/22 and the DOF of a 147mm lens at F/22 and the diffraction of a 147mm lens at F/22 (which is the diffraction of an F/16 lens x1.4 as you noted) . The whole package is an 147mm lens set at F/22.