Introduction
My on-going, worldwide, search for the best macro lenses (for 35mm use) in the world has forced me to create documentation since I can no longer keep track of it all in my head.  The title should actually be "What are the Best Lenses for Macro", since many of the lenses I plan on testing are not meant for macro. Never know though... we might find some sleepers or you may already own a great macro lens.

Although I have been involved with macro/micro/close-up photography for many years I have never studied the many factors in such detail as I am doing now. I just grabbed an appropriate lens for the job from the choices I had, never doing much comparison of available products since it was all U.S. Navy property and I used what they had. A Bio-Medical (medical & legal) photographer entering an operating room with a large camera is impractical, 35mm was, and still is, the choice. Two macro lenses we're all I knew, the Micro-Nikkor 55mm f/3.5 and the Medical-Nikkor 200mm f/5.6. These 2 lenses are what put Nikon cameras into almost all Government/Military Hospitals and they hold this advantage even after 40+ years. I have both of these lenses and can't wait to see how they stack up against the competition.

As this section grows it will teach me valuable information for choosing the right lens from what I have. If you have the same lens, or are considering what to buy, it might help you too.

Specific magnification, lens performance, lens to subject distance, price, available light, weather & terrain conditions, along with several other factors, all prove themselves useful information in determining lens choice... if you have choices.

WHAT? WEATHER CONDITIONS? TERRAIN? Yes, with this information you could decide between taking out your most awesome lens for the job or one that if destroyed wouldn't make you cry like a baby. Some lenses are irreplaceable and most great lenses usually cost considerably A LOT MORE than good lenses.

I highly recommend running your own tests to find your lenses Prime Apertures or Sweet Spot, especially for macro work and other conditions where sharpness is crucial. The test is easy, just put your camera on a tripod, focus on a test chart, fine print or something along those lines, then make an exposure for all the lenses f-stops. I find full stops are enough but you can refine the test by doing 1/2, 1/3 or even smaller increments if you wanted. Then just view the results on your monitor at 100% or higher and you'll see where the lenses perform best. If you need more depth of field, (as we all do in macro work) then you can see how far you want to push the limits since most lenses continue to diminish in quality the farther you move away from the Sweet Spot. Most lenses I have used are best stopped-down about 2 f-stops, and hold on to higher qualities for about 2 more f-stops, but not always... I'm currently testing a Tominon 35mm f/4.5 and it seems to perform best wide open or at it's maximum aperture of f/4.5.

When evaluating results I find it best to view the fastest f-stop image first and zoom in on everything that's in focus as tightly as possible. This prevents me from seeing the increased depth-of-field (DOF) in the rest of the images which can give the impression of being sharper. Run the tests and you'll see what I mean.  Using your lenses Sweet Spot will increase your image quality and often to a LARGE degree!

Years Manufactured:

Build Quality:
Not mechanically measured but rather my personal rating.

Ease of use:
Can you just slap it on and go, or does it require setup, adapter or bellows? Metering, automatic diaphragm?

Appeal:
How well do I personally like the lens.

Focusing Rating:
Is the focus as smooth as butter or do you need pliers to use it? Does it spread the focus range out well?

Aperture Range:
The cameras aperture range. Information only. This category not rated.

Click Stops:
1/3, 1/2, 1, 0 or NA (no aperture)

Aperture Blades:
This is important since some out of focus elements in the photograph may take on the shape of the aperture blade construction. Rounder aperture/diaphragm openings with odd numbered blades are generally better at giving pleasing results to those out of focus areas (Bokeh). An odd number of aperture blades make for even star patterns... 7 blades creates a 14 point star. 9 creates 18 and so on. The "stars" are most noticeable in extreme highlights and reflections. (Stop your lens down to emphasize the effect)

Prime Aperture Range:
My recommended apertures for the best in sharpness and contrast for the lens as a whole, with the equipment available. Less image quality can be expected outside these ratings. When using a bellows the effective f-stop increases as you increase extension. I will not be considering effective f-stops in these tests but rather the f-stop reading from the lens. However I will relate extension used so you can calculate it if you want. Effective f-stop calculations serve me no purpose at this time and can be calculated with the information included in the review should the need arise.

Closest Distance Reading on Lens Barrel:
? Feet
? Meters

Distance to object at 1:1 on a DX format camera & Extension Required:
The distance from the lenses furthest forward piece (usually lens barrel) to the subject at 1:1. (not the film-plane and not necessarily the front lens element) This information is most useful for me since some lenses have deep-recessed front elements while others front element may extend beyond the barrel. Saving centimeters, millimeters and beyond, becomes more important as the magnification increases. In cramped quarters you'll usually want shorter focal length lenses. If you have the space longer focal lengths lenses are desired. I am using a 24mm width as a 1:1 representation, which, for these tests, is close enough.

Distance to object at Maximum Magnification, Horizontal Coverage & Extension Required:
Furthest forward piece. Normal and Reversed

The most magnification I can get out of a lens before the front element touches the subject, if I have enough extension to get there. (Currently 245mm max.) Also how much extension it takes to get the maximum magnification. Normal and Reversed. *Some common lenses, once mounted in reverse, can become very useful macro tools.

I'm especially excited to document this section so I can understand the relationship between all the factors. I have reversed lenses before but have no idea of the relationship. Years ago I was taught the mathematical formulas for calculating all thing photographic but can't remember a bit of it. I am going to run these tests before reading up on the subject and see if I can come to my own conclusions. Right now, I have no clue.

Distance to object at LEAST Magnification & Horizontal Coverage:
Furthest forward piece.

Maximum Magnification:
The most magnification I can get out of a lens forward or reversed.

Infinity-Focus on Nikon:
It is difficult to get adapters that will allow the use of other lens mounts on Nikon Bayonet cameras without the use of additional optical glass if you need infinity focus capabilities. Unless you must have infinity focus, don't even think of putting anything in the way of the original lens design other than filtration. Anything added to the lens that the light must pass through alters the outcome and MAY degrade quality.

Adaptability:
How easily you can adapt the lens.

Adapter:
The adapter required to mount the lens to your 35mm camera.
NOTE: The "required" use of any adapter, including bellows, downgrades the lens in some of these ratings, even though most higher magnification lenses do require them.

Lens Mount:
The type of camera my lens specimen was made for and other mounts I've seen it in.

Filter Size:
(If a filter can be added) Some lenses or techniques limit or eliminate the possible use of a mounted filter. NOTE: Filters are more glass to shoot through.
1. Only use them when you should, but ALWAYS have one on the lens when not in use for the added protection. Trust me, you'll be glad someday by following this advise.
2. Buy the best you can afford for shooting filters and buy cheap ones for protection.
...now I need to create a section on filters to elaborate on this.

Dimensions:
Lengths & Width without body cap.

Weight:
Without caps, filters or hood. (naked)

SCENE or Overall Apparent Sharpness:
Personal rating.

You be the Judge: NR
Test shots for examination.

Focus Curvature: NR
If you have ever gotten real close to a small flower, focusing on the center, and wanted the center as well as the up-lifting petals to be in focus, you'll want what we'll call "Near Focusing" or "Concave Focusing" lenses. These lenses, when focused will create greater DOF towards you.

If you want to photograph a document or old photo, you want what is most commonly referred to as a "Flat Field" or "Flat Field Focusing" lens. If you were to use a near-focusing lens on the same document the farther out from center, the more out of focus your results would be.

I am quite curious what these results will show. I will try to build a visual diagram from gathered measurements and see if it is worthy of noting... I'm not sure at this point. The information may also prove to hard to calculate with my primitive setup for measurement. It would make sense that lenses are either flat-field or near-focusing but I'm curious to see if any lenses focus farther away from flat.

Bokeh:
Bokeh is how pleasant the out of focus portions of an image look. Some just fade away gracefully and others  diminish image quality. Bokeh is a critical factor in some cases for turning good images into great images.
Personal rating.

Color Saturation:
How deep the colors get.
Personal rating.

Color Accuracy:
All lenses produce different renderings of color in images, even different samples of the same lens. Some look just like the original scene and others produce something farther away from that original scene.
Not mechanically measured but rather my personal rating with the use of a color chart for consistency.

Contrast:
Not mechanically measured but rather my personal rating.

VERY Noticeable Problems:
An analysis of severe problems. Ghosting, flaring, color fringes or any aberration (problem) that really cause headaches will only be listed if they are to an extreme that causes personal concern. These reviews are non-biased but they are my personal observations and ratings. When possible, I try to do all testing before reading anything about the lens so as not to influence my opinion. This is not often possible because of the investment needed for some of these is high. I usually know quite a lot about what I'm buying before letting go of the dough. Contributed gear, garage sales and others sources are a good place to find equipment you are not familiar with and sometimes at great prices. eBay used to be great but with so many informed buyers it's hard to get super deals anymore. Good deals are still to be had though.

Availability:
Can you get one online or do you have to know an Egyptologist?

Serviceability:
How easy is it to get fixed?

Reparability:
How easy is it to fix?

Cost When New:
If available.

Used Cost or Estimated Market Value:
Most the lenses I use are no longer made. New, high-quality optics are especially expensive and that's how this whole What is the Best Macro Lens? section got started. I have bought many used lenses for using in 35mm macro work. I am continually looking for the ultimate lenses and once into macro/micro work you soon find out that there is no single lens right for everything, but many great lenses for specific purposes, so what IS the best macro lens??? It depends on your needs. As this section grows you'll understand this more.

Overall Rating:
This rating is subject to change!!! Rating is on a curve of the lenses tested here. There may be superior lenses tested which could lower other lenses ratings. These ratings will not be posted until I have several reviews to compare.

Critical Rating:
This rating will only take into account the following information; Sharpness, Saturation, Contrast, Prime Aperture and VERY Noticeable Problems.

Pros:
What I like about this lens?

Cons:
What I don't like about this lens?
Some of the Cons I list are not much of an issue when using the lens for macro and is for overall rating purposes only.

Buy Rating:
My recommendation on buying the lens.

Alternative Choices:
Some Alternatives to the current lens you are viewing.
NOTE: With the aid of adapters you can get just about any lens working on a bellows for macro shooting.

Comments:

Final Comments:

Related information:
Additional documentation that I found useful.

I cannot begin to document all the possible macro lenses since just about any lens can be used for macro if your determined enough, but I will give you some information on a variety of lenses that you may find interesting.

BTW - if you have any old camera gear (especially lenses) collecting dust, drop me a line as I'm always looking for new equipment and I do buy some so Contact me if you have ANY to retire.

Kert Kley