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Macro Equipment

Table of Content

Introduction

Lens Table

  MP-E 65mm f/2.8 1-5x Macro Photo

EF 50mm f2.5 Compact Macro

EF-S 60mm f2.8 Macro USM

EF 100mm f2.8 Macro USM

EF 100mm f/2.8L IS MACRO USM
EF 180mm f/3.5L Macro USM

Extension Tubes

Close-up Lenses

Working Distance
Macro Lens MTF Comparison

Macro Flash
Additional Information

 


Introduction

 

Macro lenses come is a range of focal lengths. The focal length has two main effects:

 

a) The longer the focal length the longer the working distance (between the end of the lens and the subject). 

 

More working distance means difficult to approach subjects can be photographed with less risk of scaring them, this is particularly true for some insects such as butterflies and dragon flies. 

 

The other major advantage of more working distance is it makes it easier to light the subject, particularly with ambient light. For shorter focal lengths the lens can be so close to the subject the subject becomes shaded from the ambient light.

 

b) Perspective is flattened more with longer focal lengths. Although depth of field at macro distances remains unaffected by focal length for a given effective aperture (see DoF with Macro Photography), the narrow field of view of a longer lens means any background area appears more blurred. A good example of this is provided in this review. The reason behind this effect is illustrated in the diagram below.

 

 

It should be noted that working distance is not simply related to focal length, for example the EF-S 60mm f2.8 Macro and MP-E 65mm Macro Photo have life size working distances of 82mm and 101mm respectively.

 

The focal length then needs to be traded against operational factors:

 

i) Weight, generally the longer the lens the more the weight. When photographing insects in the daytime the photographer is almost forced to work handheld. Often working at difficult angles to get the subject framed well, and trying to hold the equipment to within fractions of a millimeter to obtain accurate focus. In addition to the weight of the camera and lens he may well also be using flash, further adding to the weight issue.

 

ii) Handholding in ambient light, a 180mm lens is at nearly a 1 stop disadvantage in terms of shutter speed compared to a 100mm for handholding before even considering weight. 

 

NB The normal minimum safe shutter speed rule 1/focal_length/crop_factor needs to be modified for macro work. At life size the field of view of a lens is halved, as if it's focal length had doubled. 

 

So in normal photography a 100mm lens on an APS-C camera would have a minimum safe handhold speed of 1/160. For macro work this should be considered to be 1/320.

 

iii) Reach when working with a tripod. With a tripod the focal length is much less of a problem, indeed sufficient working distance is required so the tripod legs do not interfer with the subject.

 

iv) It is possible to have too much working distance, particularly with low magnification subjects like flowers. Too long a focal length can mean you may have trouble getting back far enough in some situations.

 

For all the above reasons a macro lens in the 100mm region tends to be an optimal trade off in the above areas for general macro work.

 

Focus is normally achieved using manual focus, although AF can work quite well with the modern internal focus lenses manual focus tends to give better control.

 

The general technique is to use the focus ring to set the magnification desired and move the camera closer and further away from the subject to place the plane of focus. It is also important to align the plane of focus to maximize the amount of the subject in focus. Thus along the body length of an insect but intersecting with the eyes. 

 

A common technique with animate subjects is to stalk in, starting with a low magnification and slowly get closer thus increasing magnification. With a specialist lens like the MP-E 65mm this technique is almost essential, otherwise finding the subject can be very difficult at 3:1 or more.

 

Depth of field is very small, but very small apertures can not be used without introducing softening due to diffraction. Manual or software derived focus stacking methods can be used to improve depth of field.

 

Flash is a great boon with macro photography, particularly with insects as it provides plenty of light and freezes motion. Options are:

 

a) Camera Internal flash if available, or hot shoe mounted flash

 

Limited modeling angle and so rather flat lighting. Lens may get in the way with shorter lenses at significant magnifications. 

 

The 20D internal flash works OK up to life size with the 100mm macro but needs ISO 200-400 and +1-2 FEC to get the correct exposure. Good for getting started or emergency use.

 

b) Ordinary flash on a bracket.

 

This is very popular and can give good results specially with a large diffuser, I used this method in pre EOS film days. The down side is it is relatively bulky and heavy and less easy to make fast lighting adjustments. Gives good modeling even with long lenses. Possibly a good choice if an ordinary flash is already owned or needed for other applications.

 

c) Specialist macro flash

 

With Canon this falls into two options, the MR-14EX ring flash or the more powerful and flexible MT-24EX twin flash. 

 

The ring flash tends to provide more flat lighting although some ratio control is possible, it is cheaper and slightly more compact. This type of flash can cause unnatural ring highlights in shiny areas of the subject like insect's eyes.

 

The twin flash provides more control over lighting angle and good modeling with MP-E 65mm and 100mm macro using the supplied lens bracket.  With the 180mm modeling will be less effective however the heads can be removed from the supplied bracket and placed on ordinary brackets further off axis from the lens to improve modeling if desired. 

 

At high magnifications (3-5X) with the MP-E 65mm the twin flash flash heads can be in the way of subjects if they are on a flat surface but if this can be avoided excellent modeling is possible. In some circumstances the ring flash might be easier to use. The twin flash permits control of the focus lights from the camera shutter button, this is very important for use with the MP-E 65mm at higher magnifications.

 

For more on the macro flash options see the Macro Flash Section.

Issues with flash for macro use are essentially two fold. The first is in common with ordinary flash use, the harshness of direct flash, particularly as many macro subjects contain both very light tones and very dark tones and even specula "metallic" like surfaces. This is principle caused by the small size of the light source, in normal photography the well known solution is to bounce the light off a reflector such as a flash umbrella or a nutrally coloured ceiling or wall to increase the size.

 

The second is light falloff due to the inverse square law, again an issue with ordinary flash use that can be more significant for macro work. Any object that is 40% further away will be one stop darker than the subject and anything that is 40% close will be one stop brighter. It is this effect that causes the characteristic dark background to flash light macro shots.

 

The effect can be see in the below diagram:

 

 

The close distance flash is say 14 cm away from the subject and the background is 9 cm behind the subject, a ratio of 1.64 resulting in a 1.3 stop difference in illumination for the background compared to the foreground.

 

For the far flash at 30 cm away from the subject the ratio is 1.3 resulting in a 0.75 stop difference of illumination for the background.

 

Although this only amounts to a 0.3 stop difference background in illumination ratio this is made worse by the reduced apparant size of the illumating flash at longer range as discussed below.

 

However the distant flash subtends a much smaller angle from the subject than for the close flash, approximately half the size.

 

So we see that with a lens mounted flash with relatively short lenses at higher magnifications such as the MP-E 65mm the main issue with flash is the change in illumination level across the subject. The size of the flash head is large compared to the subject, with the MP-E at 2:1 to 3:1 the MT-24EX flash heads subtend about 90 degree of arc from the subjects perspective. So some mild diffusion to ensure the illumination across the flash aperture will help, but the main issue is light fall off due to the inverse square law.

 

For a longer focal length lens or a flash mounted off lens and so distant the issue is more one of the small size of the flash head from the subjects perspective. In this situation a large diffuser or reflector is the most effective method to soften the light.

 

 

 

 

Lens Table

 

Lens

Diameter

(mm)

Length

(mm)

Volume

(mm^3)

Mass

(g)

Filter Size (mm)

Focus Distance at 1:1 (mm) Working Distance at 1:1 (mm)

Cost

Tests and Reviews

MP-E 65mm f/2.8 1-5x Macro Photo

81

98

504994

730 Ex Tripod Mount

58

240 101.0

£719.00

(5/05)

[1] [2] [3]
EF 50mmf2.5 Compact Macro 67.6 83 297894 280 52

N/A

(230 at 1:2)

N/A

£196

(2/07)

[1] [2] [3]
Life-Size Converter EF for Compact Macro 67.6 34.9 125259 160 N/A 240 53-78 [1]

£229

(2/07)

 
EF-S 60mm f/2.8 MACRO USM 73.0 69.8 292140 335 52 200 86.2

£282

(5/06)

[1] [2] [3] [4]
EF 100mm f/2.8 MACRO USM   79.0   119.0 583299 600   58  310 143.0

£394

(5/05)

[1] [2] [3] [4] [5]
EF 100mm f/2.8L IS MACRO USM  

 

77.7 123.0 583450 625 67 300 129.0 £624.98 (12/10) [1]
EF 180mm f/3.5L Macro USM 82.5 186.6 997492 1090 72 480 245.4

£1039

(5/05)

[1] [2a] [2b]

[2 1.4X]

[2 2X] [3] [4]

 

[1] The 50mm f2.5 focuses to 1:2 via front group extension, the LSC increases this to 1:1, there is uncertainty about the WD as it is not know how much the lens extends. The lower value would be correct for OLE focus.

 

Extension Tubes

 

EF 12 II

12mm

 

£69.00

EF 25 II

25mm

 

£109.00

 

MP-E 65mm f/2.8 1-5x Macro Photo

The first and foremost is the probably unique MP-E 65mm. This is a true Marco photography lens capable of magnifications between 1X and 5X, i.e. unable to focus at infinity, so a conventional macro lens such as the 100mm or 180mmis needed to fill the infinity to life size range.

This lens is a marvel to use. In the past I have used all the cheaper methods to get to near life size and beyond, up to about 2-3X including, close-up lenses, extension tubes, bellows and reversed wide angle lenses. These are all clumsy to use. Photography at more than 1X will always be fraught with problems but this lens takes out a lot of the agro.

There are a number of excellent review of this lens on the web but Frank H. Phillips’ article on Luminous-Landscapes is probably the most useful (his on webpage is here), there is also a review by Philip Greenspun.

A point to note is the MP-E 65mm changes magnification by front group linear extension with the rear group remaining fixed in a floating system to correct aberrations. So the pupilary magnification will change with image magnification, probably with a small focal length change also. For 5X the lens is up to nearly 3 times the lens length for 1X. See the picture in Frank Philips’ article.

Another point to note is that Canon state the MP-E 65mm is not compatible with either the EF 12 or EF 25mm extension tubes or either teleconvertor. However, all can in fact be used.

See the section on Working Distance.

Comes with the tripod mount adaptor B included. If like me you use the Kirk Photo quick release equipment note that the recommended lens plate LP-41 is too large for use with the MT24-EX flash and can interfere with the flash mount ring in some orientations. Use a smaller plate, I use the Universal Plate PZ-3.

There is a little known special lens hood (Canon part # CAN0028T225) intended for use with the MT-24EX flash (B&H page). See the flash section.

Lens Hood for MP-E65  #CAN0028T225

The lens pupilary magnification is variable with an internal focus lens and is useful for DOF and light loss calculations, this has been measured here. However, measurement at low magnification values is doubtful as the fixed light baffle inside the lens obstructs clear view of the apparent iris diameter. As this lens is focused by overall linear extension any variation in pupilary magnification can only be due to the rear floating element, the assumption of a constant pupilary magnification of about 0.8 is probably reasonable. 

Magnification 1 2 3 4 5
Pupilary Magnification 0.85 0.8 0.7 0.77 0.8

 

Back to TOC

 

EF 50mm f2.5 Compact Macro

 

A low cost macro lens, not as sharp as the other macro lenses going by the MTF data. Only capable of 1:2 magnification as is requiring a teleconverter like accessory called the life size converter to get to 1:1. Another disadvantage is the lens can not be used with a tripod mount adaptor.  As this lens has a 52mm filter thread an "Macrolite adaptor 52mm (for filter thread mounting)" is required to be able to fit a macro flash.

 

 

EF-S 60mm f2.8 Macro USM

 

A very sharp short backfocus lens for crop cameras only. Although sharp the short focal length leaves little working distance at 1:1, it is however relatively small and light. A disadvantage is the lens can not be used with a tripod mount adaptor. As this lens has a 52mm filter thread an "Macrolite adaptor 52mm (for filter thread mounting)" is required to be able to fit a macro flash.

 

 

EF 100mm f2.8 Macro USM

 

A very sharp macro lens with good performance at normal distance and good autofocus performance doubling as telephoto for general photography. An ideal balance between working distance and weight for general and insect macrophotography. 

 

Takes the (optional) tripod mount adaptor B as used with the other TRA compatible macro lenses but requires an adaptor part YG2-0500-000 not used with the other lenses. This should be available as a spare part from Canon's parts distributor in your territory, otherwise the whole TMA-B need to be purchased. See these notes on obtaining and using this adaptor.

 

Can be used at life size with the internal flash on the 20D. Some people have reported good results using with a Canon teleconverter with a thin extension tube between the converter and lens (although this is not sanctioned by Canon).

 

Some complain about the very large hood which although usable for life size gets very close to the subject. The hood for the EF-S 60mm f2.8 the EF-67B fits the 100mm and is about half the length and helps this issue.

 

The lens pupilary magnification (P) is variable with an internal focus lens and is useful for DOF and light loss calculations, this has been measured. Also, as the lens is internal focus the light loss has also been measured. These are reproduced below and compared against the light loss of a typical over all linear extension lens.

 

Magnification (M)

(infinity focus)

0.2 0.33 0.5 0.67 1.0
Pupilary Magnification (P) 0.73 0.73 0.7 0.6 0.52 0.32
Subject-Focal Plane Distance Marked (Metre) inf   0.49 0.39 0.35 0.3
Light Loss (Stops) 0 0.6 1 1.3 1.7 2
Light Loss for an OLE with P=1  (Stops) 0 0.5 0.8 1.2 1.5 2

 

EF 100mm f/2.8L IS MACRO USM

This new image stabilised macro lens created quite a lot of interest when released. 


Currently being sold in parallel to the existing 100mm f2.8 Macro USM (often now referred to as “the classic” despite there being an earlier 100mm macro that did not sport internal focus and USM) rather than replacing it, the lens has been provided with the first in a new generation of IS systems, Canon publicity quote (bold added):


"The new Hybrid IS system features up to 4-stop correction, compensating for the effects of camera shake, during normal shooting. Low friction ceramic balls support the moving elements, which allows for the amazingly smooth movement – needed when compensating for camera shake during macro shooting. Hybrid IS corrects shift movement – problematic when shooting up close -as well as angular movement providing photographers with the benefit of up to 2 stops at 1.0x magnification."


Perhaps Canon read my thoughts on macro IS here, more on this later. Hats off to Canon for not marketing an IS macro lens until they had an effective technical solution. The Nikon VR macro lens disappointed many due to its reduced VR effect at magnifications above 1/60 and effectively nothing at life size.


I do not own this lens so the discussion here is based on Canon specifications, reviews and comments by experienced macro shooters on forums.
Despite being a macro lens of L designation there are some surprising omissions in what is supplied in the box and compatibility, a quick check list follows:


i) Included Accessories: Soft Lens Case, Lens Hood, Rear and Front cap, User Manual.


ii) Notably a tripod mount adaptor is NOT included at odds with the 180L and MP-E.


iii) If you do want a TMA then you need to get the Canon Tripod Mount Ring D, a special design for this lens. Unlike all the other lenses that use the TMA-B design this adaptor is a hinged design sillier to the TMA-A. This means there is no commonality with other macro lenses TMAs. The hinge based TMAs have always seemed less solid to me but do have the advantage of being fitted without dismounting the lens.


iv) Unlike the 100mm macro “classic” the lens can not accept either Canon macro flash directly due to the large front element size, the user must get the Canon 67C Macrolite Adapter. This is rather like the 180L, it can be a nuisance as it means you can not fit the lens cap with the ring fitted.


v) Considering this is an L lens it is surprising it is not compatible with either the EF 1.4X or EF 2X teleconverters unlike the 180L.


vi) Needless to say the lens is compatible with the EF 12mm and EF 25mm extension tubes.

From the Canon lens manual the light loss is specified as:

Magnification 0.200 0.333 0.500 0.667 1.000
Light Loss (stops) 0.667 1.000 1.333 1.667 2.000

This is essentially the same as the 100mm macro "classic".

Other than the addition of the Hybrid IS other notable comparisons with the 100mm macro “classic” are:


a) Improved focus limiter covering Full Range, 0.5m to infinity and 0.3m to 0.5m.


b) Nine rounded aperture blades (the 100mm classic and 180L both have eight blades, this should provide some improvement of out-of-focus highlights).


c) The AF action is reported to be faster than the old lens, although it is not clear if this is due to the extra focus limiter setting or not.


d) The manual focus ring travel is similar or the same to the classic (the 180L is notable better in this respect).


e) The 100L is in theory a little sharper than the classic but most users report no obvious difference in use. Indeed, in the macro range the main limitations are already the trade-off between depth of field and diffraction softening.


f) The 100L is reputed to have a more pleasing bokeh than the classic, however the classic is no slouch in this respect.

The only reasonably scientific testing I have seen of the lens notes the IS is very effective at normal distances but is much less effective at close distances:


The Hybrid IS is clearly having some positive effect even at 1:1 magnification, but in truth the benefit isn't huge (closer to 1 stop in this test as opposed to Canon's claimed 2 stops).”


This agrees closely with the impressions of experienced macro shooters who use the lens. In fact a number have noted that they turn off the IS when working at macro distances as the IS actively interferes with techniques such as focus stacking.


Surprisingly, when launched most of the interest in this lens was from people wanting an available light portrait lens rather than macro shooters, or at least that is the impression I got watching forum chatter.


There were at the time of this lens’s announcement rumours of a 200mm f/4L IS Macro to perhaps replace the 180L. As the longer macro lenses tend to be used for subjects such as butterflies and dragonflies at magnifications of 0.3X to 0.5X the IS might be more effective here. However, a year later such a lens has not yet been announced. Judging by recent Canon prime L upgrades the price of such a lens can be expected to at least double.


So am I upgrading? No, certainly not at present at least. I currently use three macro lenses and reading others experiences I don’t think the benefit is sufficient, although the normal distance low light application could be compelling if my range of subjects change. If I was starting from scratch then yes I would probably choose the L lens.

 

EF 180mm f/3.5L Macro USM

This is a long focus macro lens giving focus from infinity to life size. Focus control: Inner focus method.

The advantage of this lens is a long working distance of 0.48M compared to 0.31M with the 100mm f2.8 macro.

Equipment

Min Focus

Length

IP to Mount Front of lens to subject
EF 180mm f/3.5L Macro USM 480.0 186.6 44.0 245.4
EF 100mm f2.8 Macro USM 310.0 119.0 44.0 143.0

So providing about 102mm more working distance from the front of the lens at 1:1. (See also Working Distance).

Note that the 300mm f4L IS has quite a close focus distance and with a 2X converter is capable of 0.48:1 magnification at a working distance of 1.2M from the lens. This is more than the 180mm even with a 2X converter and is probably enough magnification for the larger bugs such and butterflies and dragonflies. 

This is a significant additional working distance when photographing insects in the field, however the extra weight and size will limit hand held use. Another point is that in they field a long working distance can be a disadvantage if the subject is in obscuring undergrowth, and can cause you to run out of room in a studio setting.

Another advantage is this lens can use the EF 1.4X and EF 2X teleconverters to further increase magnification or working distance.  

The 180mm macro can be used at life size with the 20D popup flash if the lens hood is removed just as the 100mm macro can be.

Comes with the tripod mount adaptor B and a white shoulder/belt bag.

NB a 72mm "Macrolite adapter"  is required for use with either of the Canon macro flashes, this is not included. Also the adapter needs to be removed for use at normal distances as it can cause vignetting.

Magnification (M)

0

(infinity focus)

0.1 0.2 0.33 0.5 0.67 0.83 1.0
Pupilary Magnification (P) 0.62 0.62 0.6 0.64 0.55 0.55 0.5 0.4
Subject-Focal Plane Distance Marked (Metre) inf 2 1.2 0.84 0.66 0.57 0.51 0.48

Light Loss (Stops) 

Lens Manual

      0.667 0.667     1.333
Light Loss for an OLE with P=1  (Stops) 0   0.5 0.8 1.2 1.5   2

 

Reviews [1]

 

Extension Tubes

Used to increase magnification further. The Kenko ones have metal mounts but plastic bodies. The connections preserve IS and AF functionality. They do not come with a pouch or case but I use the LP814 Lens Pouch normally matched to the Canon EF 50mmf2.5  Macro Lens for them.

Update: I have had the Kenko tubes accidentally release it in use, this has happened three times to me. Subsequently I have switched to the Canon tubes which lock much more tighly.

Equipment

Length

Costs (May 05)

EF 12 II

12mm

£69.00

EF 25 II

25mm

£109.00

Kenko Extesion Tube Set for Canon AF fitting DG

Set of 12, 20 and 36mm

£110.00

 

Below are some plots showing the magnification, subject range and depth of field for various focal length lenses and extension tube lengths. Assumptions are that: Pupilary Magnification=1, Nodal Separation=0, Format Size APS-C.

 

Some tables of magnification and working distance with Kenko tubes.

Table of Magnification (Min)
Lens/Tube 12 20 36 12+20 12+36 20+36 12+20+36
100mm f2.8 Macro 0.11 0.18 0.36 0.32 0.52 0.59 0.71
100mm f2.8 Macro + EF 1.4X II [1] 0.15 0.31 0.50    

 

 

 

 

 

100mm Macro TC Factor 1.37 1.79 1.39        
200mm f2.8L II     0.17       0.34

200mm f2.8L II

 + 1.4X

0.48
300mm f4L IS             0.22
Table of Magnification (Max)
Lens/Tube 12 20 36 12+20 12+36 20+36 12+20+36
100mm f2.8 Macro 1.29 1.42 1.69 1.57 1.83 2.00 2.20
100mm f2.8 Macro + EF 1.4X II  [1] 1.76 1.83 2.20        
100mm Macro TC Factor 1.36 1.29 1.30        
200mm f2.8L II     0.37       0.61

200mm f2.8L II

 + 1.4X

0.85
300mm f4L IS             0.58
Table of Working Distance (Max) (mm)
Lens/Tube 12 20 36 12+20 12+36 20+36 12+20+36
100mm f2.8 Macro 940 590 290 340 220 210 170
100mm f2.8 Macro + EF 1.4X II  [1] 940 580 300        
100mm WD TC Factor 1.00 0.98 1.03        
200mm f2.8L II     1300       760

200mm f2.8L II

 + 1.4X

760
300mm f4L IS             1770
Table of Working Distance (Min) (mm)
Lens/Tube 12 20 36 12+20 12+36 20+36 12+20+36
100mm f2.8 Macro 130 125 115 128 120 115 110
100mm f2.8 Macro + EF 1.4X II  [1] 134 125 120        
100mm WD TC Factor 1.03 1.00 1.04        
200mm f2.8L II     700       510

200mm f2.8L II

 + 1.4X

510
300mm f4L IS             680

Note  [1]: This combination of Teleconverter and Lens is not sanctioned by Canon. It is possible to fit the TC by inserting an extension tube between the TC and the lens. This seems to preserve  the expected magnification and working distance.

An alternative to measurement is to use the lens formula to estimate the magnification, subject and working distances with various tubes using the data provided by Canon for their extension tube. This is provided in the tubes instruction leaflet or on the web.

The following formula can be used:

R=(r+t+f)^2/(r+t)+e=f(M+1)^2/M+e,

 M=(r+t)/f,

W=R-L-t--r-f    Eq 1

Where R is the subject distance, r is the rear node to sensor distance, f is the focal length, M is the magnification, L is the rear node to front of lens distance, e is the separation between the from and rear node and t is the length of the extension tube. 

Canon provide R, M and W at infinity and close focus for the EF 12 and EF 25 tubes. By simultaneous equations f, r, L and e can be found at infinity and close focus and then used to estimate the parameters for any added extension. Some results are tabulated below. (Note the results are not perfect and the values for the 12 and 25mm lengths will depart a little from that provided by Canon)

EF 50mm f1.4 USM

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) Working Distance Close (mm)
12 0.24 0.39 321 248 225 141
25 0.50 0.65 226 210 117 90
37 0.74 0.89 205 201 84 69
50 1.00 1.15 201 201 67 56
62 1.24 1.39 203 206 57 49

EF 100mm f2.8 Macro USM

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) Working Distance Close (mm)
12 0.12 1.19 1029 313 853 137
25 0.25 1.38 601 318 412 129
37 0.36 1.55 478 325 277 124
50 0.49 1.74 417 333 203 119
62 0.60 1.92 388 341 162 115

EF 200mm f2.8L II USM

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) Working Distance Close (mm)
12 0.06 0.23 3497 1174 3306 982
25 0.13 0.31 1865 1005 1661 800
37 0.20 0.38 1417 915 1201 698
50 0.27 0.46 1187 854 957 624
62 0.34 0.53 1066 817 825 575

EF 300mm f4L IS USM

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) Working Distance Close (mm)
12 0.04 0.30 7877 1338 7600 1060
25 0.08 0.36 4059 1231 3769 940
37 0.13 0.42 2950 1165 2648 862
50 0.17 0.49 2361 1115 2045 799
62 0.21 0.55 2042 1082 1715 754

EF 180mm f3.5L Macro USM

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) Working Distance Close (mm)
12 0.07 1.09 2828 478 2584 233
25 0.15 1.20 1603 481 1346 223
37 0.22 1.30 1258 486 989 216
50 0.30 1.41 1079 492 797 209
62 0.38 1.51 987 498 693 203

EF 24-105mm f4L IS USM at 24mm (NB only 12mm Tube is compatible)

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) (est) Working Distance Close (mm) (est)
12 0.50 0.60 187 177 150 160

EF 24-105mm f4L IS USM at 105mm

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) (est) Working Distance Close (mm) (est)
12 0.12 0.40 992 328 948 284
25 0.27 0.60 604 287 547 231
37 0.41 0.78 507 274 438 205
50 0.56 0.98 463 270 381 188
62 0.70 1.16 444 271 350 178

TS-E 24mm f3.5L

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) (est) Working Distance Close (mm) (est)
12 0.49 [0.49] 0.64 [0.62] 179 [179] 174 [171] 35 [36] 28 [24]
25 1.10 [1.10] 1.19 [1.21] 167 [167] 170 [166] 10* [9] 10* [4]
37* 1.66 1.70 173 176 4* 4*
50* 2.27 2.25 182 185 0.5* 1*
62 negative working distance

* working distance unreliable, Canon values in brackets

TS-E 45mm f2.8*

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) (est) Working Distance Close (mm) (est)
12 0.27 0.44 299 239 153 85

* Canon do not recommend using this lens with the EF25 and so do not  provide any magnification info so this method can not be applied. The Canon supplied info for the EF12 is instead repeated.

TS-E 90mm f2.8

Total Tube Length (mm) M Inf M Close Subject Distance Inf (mm) Subject Distance Close (mm) Working Distance Inf (mm) (est) Working Distance Close (mm) (est)
12 0.14 0.43 795 415 650 253
25 0.31 0.59 508 377 350 202
37 0.47 0.74 437 362 267 175
50 0.64 0.90 407 355 224 156
62 0.79 1.05 395 355 200 143

 

  Back to TOC

Close-up Lenses

Close-up lenses are small simple lenses that fit over the front of a lens using the filter thread mount. The are normally single element construction although some of the more expensive designs use two elements and provide superior reduction of aberrations.

The lenses have their power normally defined in diopters. Diopters are related to focal length by the formula:

fa=1000/D, Eq 2

where D is the close-up lens power in diopters and fa is the close-up lens focal length in millimeters.

The effect of the lens is easy to understand for a lens set to infinity focus and is reported in much of the general photography literature. When the lens is set to infinity focus it will bring parallel light rays to sharp focus. So under these conditions with a close-up lens attached the subject will be in close focus fa from the close-up lens. In a sense the close-up lens is acting the same way as reading glasses for someone with long sight. The magnification achieved is related to the lens angle of view and the close-up lens power so that:

Winf=fa and Minf=finf/fa Eq 3

Where Winf is the working distance from the close-up lens and Minf is the magnification with the main lens is set to infinity focus.

Working out the effect of the close-up lens with the main lens set for closer than infinity focus is more complex and requires the use of grownup optical formula, although still relatively simple. Referring to Smith who provides the equations for a two component optical system, recasting his equations 2.49 and 2.50 and solving for m and s by simultaneous equations yields:

ms=d+sprime-d*sprime/fb
m=(ms-sprime-ms*d/fa)/d
thus, s=ms/m   
Eq 4

Where fb is the focal length of the main lens at the focus distance of interest, sprime is the backfocus distance of the main lens at the set focus distance, d is the main lens front principle plane to close-up lens rear principle plane distance, s is the subject to close-up lens front principle plane distance and m is the system magnification. Note that standard optical sign conventions are used so the close focus magnification and working distance are:

mcf=-m and wcf=-s Eq 5

fd and sprime are referred to the objective size of the lens, so asymmetric focal lengths and non-unity pupilary magnifications, typical of SLR lenses, can be neglected for this calculation. However, when considering depth of field the depth of focus situation is the same as it would be for magnification by extension tubes, so the main lens pupilary magnification needs to be included in the normal way as per the dof equations for macro.

The main problem in applying Eq 4 is in determining d, fb and sprime. The close-up lens being thin, can be assumed to have zero nodal separation. 

For a lens focused by over all linear extension (OLE) fb can be taken as the specified focal length and sprime determined from Eq 1 buy rearrangement and finding the minimal root of the quadratic

 0=r^2+r(2fb-R+e)+fb^2 and 1/fb=1/v+1/sprime

where sprime=fb+r  and R=v+sprime+e Eq 6

Here R is the main lens sensor to subject range without the close-up lens (as specified by Canon) and e is the nodal separation of the main lens.

The quantity d can be estimated by Eq 7 where Llens is the physical lens length from the camera mount flange and Lbody is the body focus, Lbody=44mm for Canon EOS/EF.

d=Llens+Lbody-sprime-e Eq 6

For lenses focused by internal focus, the focus actions reduces the lens focal length fb whilst increasing r from its infinity focus value of zero. The nodal separation e and position of the front principle plane from the filters threads d can be expected to change also as the lens is focused. The values of fb, r and e can be estimated using the methods of the extension tube model section above.

So, due to uncertainty of these quantities the results may not be entirely accurate and are specific to a particular lens design.

The following lens are used as a basis for the minimum focus calculations:

100mm: 100mm f2.8 Macro USM

200mm: 200mm f2.8L II

300mm: 300mm f4L IS

400mm: 400mm f5.6L

420mm: 300mm f4L IS + 1.4X II

600mm: 300mm f4L IS + 2X II

First the plots for the straightforward infinity set focus case:

 

Now the more suspect closest focus set:

The values above for the 100mm macro USM, 200mm 2.8L II, 300mm f4 IS and 300 f4 IS +EF 1.4X have been checked with an old +4 Diopters close-up lens. This was too small to fit on any of the lenses and so was held close to the lens front element to check magnification and working distance. 

In general the values are in reasonable agreement, the quality of the image however, even through the viewfinder was appalling.

 

Back to TOC

Working Distance

The below plot provides some estimates for working distance for the three Canon macro.

This is likely to be a little inaccurate but is hoped to give some insight (calculator).

For the 100mm lens this gives reasonable agreement between the model and measured values:

Magnification Predicted Working Distance mm Measured Working Distance mm (Approx)
0.2 547 560
0.5 247 230
1.0 147 120

 

 

 

The MP-E 65's gain in length with increasing magnification is more than sufficient to compensate for the reduction of working distance, so a focusing slide will need to be moved away from the subject as magnification is increased except for between 1 to 2X.

Mag Working Distance (mm) Lens Length from TMA (mm) TMA Mounted Focus Slide Adjustment (mm)
1 101 90 0
2 63 120 8
3 51 154 -14
4 44 185 -38
5 41 218 -68

 

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Macro Flash

Macro Flash TOC

Introduction

Mounting Issues

Lighting Angles

Summary Information

Flash Ranges

Introduction

One thing that is indispensable at this magnification is dedicated macro flash equipment. Canon make two in the EOS Speedlight range. The Macro Ring Lite MR-14EX and the Macro Twin Lite MT-24EX.

It is possible to work with manual flash using cheap flash units mounted on flash brackets angled in towards the lens. I have done this, but it is again clumsy and looses the major advantage of through the lens flash metering, particularly with variable magnification settings where the exposure loss may change.

With the 100mm f2.8 Macro and 180mm f3.5L Macro the lens length does not change with magnification so brackets and flash could work although be a bit front heavy. This is a larger issue for the MP-E 65mm f2.8 due to the change in length with magnification.

The Ring Lite is probably the most compact solution but has less lighting control flexibility than the Twin Lite. Another potential problem is ring shaped reflections (discussion and example in this forum discussion), but these can probably be cloned out in the digital darkroom. 

As the Twin Lite flash heads will tend to be to the side of the subject more than for the Ring Flash as very small working distances this may be significant for the MP-E 65mm f2.8 but less so for the 100mm and 180mm lenses where minimum working distance is large unless extension tubes are used.

Possibly more significantly the Twin Lite has a much larger guide number. This may not be most critical with the MP-E 65mm despite the high exposure loss expected but may be more significant with a long lens at modest magnifications such as the EF 180mm f/3.5L Macro USM.  (NB the EF 180mm Macro has a filter size of  72mm and the 100mm Macro a filter size of 58mm and the EF-S 60mm of 52mm).  Another advantage of the twin flash is difussers can be fitted, Stofen for example make diffusers for the MT-24EX that are available at a reasonable price. Here are some comparative test shots with and without the Stofen diffusers fitted.

Despite the much higher price tag for the Twin Lite the maneuverability and even detachable flash heads (apparently with about 3ft of coiled flex) makes it more versatile and even usable for general photography.

Something worth noting for 20D owners is the built in flash is quite capable of illuminating the image area with the 100mm f2.8 Macro with an exposure of f22 @ ISO 100 to 400 (depending on reflections from surroundings) at ~1/3 to life size. Surprisingly the shadow of lens (without hood) seems to be just outside the image area.

It is worth noting that the EF 50mm and EF-S 60mm macro lenses have filter threads of 52mm and so require a "Macrolite adaptor 52mm (for filter thread mounting)" is required to be able to fit a macro flash.

 

Back to Macro Flash TOC

Mounting Issues

The macro flashes are designed to clip onto the front of the macro lenses. Apparently this is not possible with a protective filter fitted. 

In the case of the ring flash there is no way to fit a filter, however the twin flash does have a 58mm filter screw thread.

It seems that there is a Canon macro light adaptor that can screw into the filter and then the macro flash can then be added. 

The below are some links to discussions on this topic.

Canon Digital Photography Forums - Macro Flash Question
iBTopicCanon MR-14EX ring flash - can't use UV filter
JR.com CANON CAN55-9291 Macrolite Adapter 58C in Lenses and Adapters
Macro Twin Lite MT-24EX
No filter on EF 100mm F-2.8 USM when MR-14EX is attached!
Technical Hall - Technical report 2000.4
Using MR-14EX w-Other Macro Lenses

Another point is it seems it is possible to mount the 100mm f2.8 Macro lens hood with the twin flash (although not use the flash) but not with the ring flash.

Back to Macro Flash TOC

Lighting Angles

Using what is known of the equipment dimensions and a range of lens to subject working distances the lighting angles with each lens can be estimated.

This shows that the twin flash provides both greater and lesser angles of lighting compared to the ring flash according to how far out the flash heads are swung. The above plot estimates the mid point of the flash head and the two below the near and far edges.

At very short working distance such as may be experienced with the MP-E 65mm at high magnification the lighting angle can become very oblique or possibly be behind the subject (this is all estimate and needs to be checked). The ring flash should not have this problem never providing beyond about 50-70 degrees off axis even at 5:1 magnification. This only starts becoming problematic for working distances below about 70mm for greater than 1.3:1 with the MP-E 65mm.

The 100mm typical magnifications of 0.5:1 to 1:1 have a working distance of 130 to 230mm resulting in 12-20 degree angles for the ring flash and 2-10 to 10-40 degree angles for the twin flash.

Another small point is working in the field the ring flash may be less obtrusive to nervous insects and less likely to be obscured by undergrowth.

Further, the effect of the twin flash could be obtained with brackets and conventional flashes with difficulty, although the close to lens ring flash could not.

Discussions via web forum suggest the performance of the MT-24EX at 5X with the MP-E 65mm is perfectly acceptable. MP-E 65mm with MT-24EX Lighting Angle

Some tests with the 100mm f2.8 and MP-E 65mm with various lighting ratios with the MT-24EX suggest that only modest control is available with the as delivered ring and the 100mm. However the 65mm permits much better control of modeling. The modeling can be improved with the 100mm by spacing one or more of the flash heads further away from the axis. In the two examples included the left lamp only has been offset an additional 35mm using a slave trigger between the flash head and the lens ring mount.

The Hood available for use with the MP-E 65mm and the MT-24EX is not that well known but is presumably provided due to the flash heads being angled enough for use with 2X and above to illuminate the objective element somewhat.

This is illustrated in the below pictures. First the MP-E and flash with no hood:

Now with the hood fitted: 

And again closer in:

Tests suggest that there is little obvious advantage to using the hood unless a flash head is dismounted to use as a backlight, except possibly at 5X. Test Shots

 

Back to Macro Flash TOC

Summary Information

Equipment

Size

Mass

Filter Dia

Costs (May 05)

Macro Ring Lite MR-14EX

Control unit: 74 x 126 x 97mm

Flash assembly: 1113 x 126 x 25.6mm [5]

  430g excl Batt

[5]

[3] £329.00
Macro Twin Lite MT-24EX Control unit: 74 x 126 x 97mm 

Flash assembly: 235 x 90 x 49mm [5]

585g excl Batt

[5]

[3] £589.00

Equipment

Includes

Auto Distance Range ISO 100

Angle of Coverage

Recycle and Life

(full power)

Guide Number

(ISO 100, metres)

Macro Ring Lite MR-14EX

Soft Case [1]

 

80° in both vertical & horizontal angles [1]

  7 seconds (alkaline) 4 seconds (Ni-Cd) [1]

14

Macro Twin Lite MT-24EX

Soft Case [1]

20mm to 7.9 metres with twin heads;

 20mm to 8.6 metres with single head [2]

80° in both vertical & horizontal angles [1]

 7 seconds (alkaline) 4 seconds (Ni-Cd) [1] Count 120-180 (alkaline) [4]

22 (twin heads)

24 (single head)

[1] Information from www.bhphotovideo.com

[2] Information from http://www.ardea.org/ardea_canon_team/MT-24EX.htm

[3] Both MR-14EX and MT-24EX attache directly to EF 50mm f/2.5 Compact Macro, EF 100mm f/2.8 Macro (both versions), and MP-E 65mm Macrophoto Lenses [without filters attached] (can also be used with EF 180mm f/3.5L Macro USM via Macrolite Adapter 72C)
Can be adapted to other popular filter sizes with appropriate Macrolite Adapters; 52mm, 58mm & 72mm

[4] http://www.ephotozine.com/equipment/tests/testdetail.cfm?test_id=107 This review also notes the following for the Twin Lite with external power sources:  CP-E2 (alkaline) 0.1-4 Sec 400-2500 Life; Transistor Pack E (alkaline) 0.1-4 Sec 400-2500 Life; Transistor Pack E (Ni-Cd Pack TP) 0.1-3 Sec 330-2000 Life.

[5] Canon User Manual

From ref the following table of features:

Speedlite MR-14EX MT-24EX
introduction 2000 2001
E-TTL, FEL, FP flash Y Y
2nd curtain sync Y ?
FEC Y Y
FEB Y Y
Wireless master Y Y
Wireless slave    
modeling light Y Y
exposure confirmation Y Y
manual power range 1 - 1/64 1 - 1/64
strobe range (Hz)    
hot shoe locking pin Y Y
illuminated LCD panel Y Y
rapid fire capable Y ?
save energy (SE) function 90 sec ?
SE function override Y ?
battery AA x 4 AA x 4
lithium AA capability Y Y
external HV Y Y
Quantum 6v module    
weight (grams - w/o battery) 430g 585g
Speedlite MR-14EX MT-24EX

 

 

Back to Macro Flash TOC

 

 

Flash Ranges

 

The flash manuals provide minimum aperture limits at low magnifications and maximum aperture limits at high magnification, presumably due to limits on how little flash power can be emitted, listed here for ISO 100.

 

EF 100mm f2.8 Macro USM

 

At least 2M at f8 and wider. 1.4M to 0.7M for f11 to f22.

No less than 0.7M to 0.38M (1:2) at f2.8 to f8.

 

 

EF 180mm f3.5 Macro USM

 

At least 2M (1:10) at f11 and wider. Up to 1.2M (1:2) for f16-22.

No less than 1.2M (1:2) at f5.6 and wider.

 

 

MP-E 65mm f2.8 1-5X Macro Photo

 

No wider than f8 at 1:1; f5.6 at 2:1; At  4:1 or more up to maximum aperture. 

 

 

Back to Macro Flash TOC

  Back to TOC

 

Additional Information

Improving Macro Depth of Field with a Digital Composite

EOS Documentation Project:  Canon MR-14EX Macro Ring Lite   and  Canon MT-24EX Macro Twin Lite

B&H Pages: MR-14EX MT-24EX

Ephotozine Review of MT-24EX

MT-24EX Review

FM Reviews MR-14EX MT-24EX

Example of off-mount use of heads with MT-24EX (supplier)

Canon Canada Info MR-14EX MT-24EX

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Last Updated 28/12/2010

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