About MACRO filters and lenses

[ajohnw]

There is another aspect that relates directly to macro lenses - they will have been computed to work at their best at typical macro reproduction ratio's. In other words closer focal distances. They generally also have very low distortion figures.

It's essentially incorrect to describe a magnification ratio based on a crop factor. Totally misleading and assuming that higher pixel densities will make up for that aspect is basically incorrect as well. On m 4/3 a decent resolution from a a lens is around 2800 lw/ph. Graphs generally allow up to 3,000 max. That is line widths per picture height which accounts for the actual height of the sensor. Full frame starts getting good at 3,200 lw/ph. These figures happen to relate to Canon's 100mm macro on a 5D MkII and Olympus 60mm on 16mp n 4/3. The Canon IS version comfortably reaches over 3,200 lw/ph. Odd isn't as the pixel density on m 4/3 is way way higher than the full frame camera. The IS version also has truly negligible distortion. The other 2 don't if some one wants to do precise reproduction work.

Stick the same basic canon macro lens of 15mp APS and the figure comes out at 2,280 lw/ph. The IS version does a bit better but still under 2,800 lw/ph. This is because they are full frame lenses.

Go down to Nikon 1 and good/excellent comes in at around 1,800 lw/ph. Not macro in this case.

So now some might realise that what ever format is used the main thing is to get the largest image possible on the sensor. Crop factor makes that more difficult really. If the m 4/3 lenses are 2:1 it would make no sense at all using 2:1 in situations where 1:1 could be used.

If some one looks at these resolution figures carefully they might conclude that the lenses for smaller sensors are better than those made for larger ones. Basically it's easier to make more precise lenses for smaller formats due to scale effects but larger format still win out at a cost when it comes down to actual resolution. Pixels - there comes a point where increasing densities doesn't really achieve anything.

John
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[DanK]

It's essentially incorrect to describe a magnification ratio based on a crop factor. Totally misleading and assuming that higher pixel densities will make up for that aspect is basically incorrect as well.

Go down to Nikon 1 and good/excellent comes in at around 1,800 lw/ph. Not macro in this case.

So now some might realise that what ever format is used the main thing is to get the largest image possible on the sensor. Crop factor makes that more difficult really.

I think this confuses three very different things: magnification, reach, and resolution.

"1:1 macro" refers to magnification, that is, the size of the image on the sensor relative to the size in real life. It is not the same thing as reach, it has nothing to do with resolution, and it has nothing to do with sensor size. It is simply the ratio of two dimensions.

"Reach" is usually used to refer to the distance at which one can fill the frame with an object of a given size. This, unlike magnification, IS a function of sensor size, because sensor size is one of the factors in the trignometric equation for angle of view. This has nothing to do with resolution or pixel density.

Pixel counts and resolution are both factors that affect image quality independent of reach and magnification, particularly if one prints large.

[ajohnw]

Being fair to Olympus - and Panasonic, it seems, I don't own one of their macro lenses but have yet to come across any macro lens that gives 1:1 at the distances where something around 2:1 would be expected. The working distance is 2nd hand info as well so could even be incorrect.

It's also possible to do a lot of work with a lens that goes to 2:1 max magnification. This for instance was shot on m 4/3 with a Pentax 100mm macro lens set at around 2:1. The working distance was in the order of 200mm not 120mm that would be expected from a 60mm lens at 2:1.

Not at all sure what type of beast this is. It doesn't look like a wasp or a bee to me. Unusually I seem to have enough DOF on this subject. This is an uncropped full frame view.



John
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[Inkanyezi]

I think we should not confuse things too much for the OP.

Chattering about the importance of pixel pitch, or for that sake line pairs per pixel height or even if we go down to diffraction limits is well beyond comprehension for most ordinary mortals. It comes down to hubbub, lots of words, very little value of information.

When we talk about imaging small creatures or plants, the size of the subject compared to the image, the frame that is captured, is more helpful.

But how about helping the OP with comprehensive information?

Any camera, regardless of sensor size, can capture a decent image. If we instead look at how easy it is to manage, this might be a factor worth considering for the person that might want to take such photos. There are mainly two approaches for most close-up work of reasonably large items. Either you use a dedicated macro lens, or you make do with something else that you adapt for close-up work. Either way may approach a size in the final image that a "true macro" lens would accomplish on a full frame sensor - beware, I do not talk about pixel peeping or ultimate image quality as often is done among photo freaks, but a useful image, that shows the desired detail.

Then, being a novice, and provided there is an APS-C camera body as the Canon EOS 1100D, and one does not have a telezoom lens, the most fruitful approach to the close-up world is getting a macro lens. My suggestion then would be getting one that is inner focusing and has a reasonable working distance. For convenience also it is good to have optical stabilisation.

Then I can find five reasonable lenses, one from Canon, three from Sigma and one from Tamron. They are:

• Sigma EX 105/2,8 DG OS HSM, 1500 BRL
• Tamron AF SP 90/2,8 Di VC USD, 1540 BRL
• Canon EF 100/2,8L IS USM Macro, 2845 BRL
• Sigma EX 150/2,8 DG OS HSM APO Macro, 3180 BRL
• Sigma EX 180/2,8 DG OS HSM APO Macro, 5025 BRL

The prices are approximately what I would have to pay for those lenses in Sweden, including VAT. I don't know what they would cost in Brazil, but it gives a general image of what it could cost. I think the longer lenses might be out of the question, as the camera probably was purchased as a budget model, and the two first lenses in the list seems most reasonable in that perspective.

Close-up equipment of other types would be more difficult to manage, but this kind of lenses is very easy to use. Just put the lens on the camera and point at the subject. If the camera is too close to find focus, back off a bit.

And the image quality will be superb with any of those.

[Inkanyezi]

Not at all sure what type of beast this is. It doesn't look like a wasp or a bee to me. Unusually I seem to have enough DOF on this subject. This is an uncropped full frame view.

To me, it looks like a drone bee.

[deetheturk]

This is a Drone Fly (Bee mimick fly)they are part of the Hover Fly family!

David

[DanK]

This is a Drone Fly (Bee mimick fly)they are part of the Hover Fly family!

Beat me to it. For folks who don't stare at bugs, both the eyes and antennae are give-aways that this is some sort of fly. Compare this honeybee:



to this bottle fly:



In John's photo, you can clearly see the paddle-like antennae in front of the eyes, and the eyes have a structure typical of flies. People notice the bodies more than these features, and the bodies of the hoverflies with which I am familiar all look like bees or wasps of different types.

Urban--I think your last post has a lot of very good information and has steered the discussion back toward the OP's question. I would partly disagree only with this:

For convenience also it is good to have optical stabilisation.

As far as I know, the optical stabilization in most macro lenses is the conventional sort, that is, it compensates for angular motion. This is helpful for non-macro uses of the lens but is of very little help in macro work. The Canon 100L has hybrid IS, which helps more in macro use, but I don't think other manufacturers have started producing it. Somebody can weigh in if I am wrong.

[ajohnw]

The E-M5 has IS in all directions. I read something about a new Tamron macro lens that made me wonder if they have done something similar to Canon - wishful thinking on my part I suspect.

Currently at least in the UK the Tokina 100mm F2.8 macro is rather well priced. I suspect that this may be because they are about to introduce a new one that has fixed length / internal focusing like most of the others now. The length doesn't extend much as it's focused down to 1:1 anyway.

As I mentioned earlier a number of people obtain excellent results with standard longer zoom lenses plus extension tubes and often a 1.4x converter. Part of this is down to wanting longer than normal working distances and avoiding the cost of something like a Nikon 200mm macro lens. As most people who own a DSLR usually finish up with at least 2 lenses, one significantly longer than the other a telephoto plus extension tubes / close up lens / converter is worth considering and the intent to do this might influence which lens is actually purchased. It's best to work out what can be done before actually making a purchase.

I do have a couple of full resolution shots on the web. One taken at a lower magnification ratio and the other at near 2:1. Taken with a late Pentax film macro lens on an M 4/3 adapter. They illustrate another problem with macro work. Reduced to typical posting sizes detail is lost.

The moth was resting up. Slight damage to the wing

http://www.23hq.com/ajohnw/photo/8059501/original

And the spider. Unfortunately my dog saw it spinning the a cocoon round the insect and disturbed the web and the spider scooted away. When I went back later it was all over.

http://backup.cambridgeincolour.com/...82543/original

These give some idea of the likely resolution of a sensor of this size. More than enough really.

John
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[jcuknz]

Being fair to Olympus - and Panasonic, it seems, I don't own one of their macro lenses but have yet to come across any macro lens that gives 1:1 at the distances where something around 2:1 would be expected. The working distance is 2nd hand info as well so could even be incorrect.

It's also possible to do a lot of work with a lens that goes to 2:1 max magnification. This for instance was shot on m 4/3 with a Pentax 100mm macro lens set at around 2:1. The working distance was in the order of 200mm not 120mm that would be expected from a 60mm lens at 2:1.

Not at all sure what type of beast this is. It doesn't look like a wasp or a bee to me. Unusually I seem to have enough DOF on this subject. This is an uncropped full frame view.

I think you are behind the times as I was until recently when I realised that just a two dioptre CU lens would enable a 1000mm AoV lens to give a 1:1 result, even when the sensor is only perhaps 8mm across. A 500mm AoV is getting pretty close but 1000 or 1200 I think kills off the idea that bridge cameras cannot have 1:1..... these days they can

Of no great interest to the DSLR owner with the ability to use extension tubes or bellows.

I find that a 38mm subject filling the sensor meets just about all my needs ... that is a 2D and 430mm AoV ... but need a 4D now with MFT to get similar [ slightly better] with only a 280mm AoV lens. But I have never gone for 'bug-eyes'

[ajohnw]

I think you are behind the times as I was until recently when I realised that just a two dioptre CU lens would enable a 1000mm AoV lens to give a 1:1 result, even when the sensor is only perhaps 8mm across. A 500mm AoV is getting pretty close but 1000 or 1200 I think kills off the idea that bridge cameras cannot have 1:1..... these days they can

Of no great interest to the DSLR owner with the ability to use extension tubes or bellows.

I find that a 38mm subject filling the sensor meets just about all my needs ... that is a 2D and 430mm AoV ... but need a 4D now with MFT to get similar [ slightly better] with only a 280mm AoV lens. But I have never gone for 'bug-eyes'

Behind the times? I've made no mention of using bridge cameras. If you want to try that arrangement go ahead

I have.

John
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[jcuknz]

If I didn't make myself clear earlier I would suggest that with only a 15-55 lens the CU lens is not the answer and if you cannot afford a true macro lens then extension tubes, the variety which connects lens to camera controls, is the way to go.

I come from bridge cameras with 'long zooms' and the CU lens is the logical answer there ... but if you only have DSLR with a 'kit' lens then auto extension tubes are best if you don't want to splurge on a macro lens.
If you have the typical 'two lens kit' it becomes more like a bridge camera solution when using the 'long lens'.
The drawback may be cost ... my lens requires a 55mm mount at US$18 < 25 but a 77mm equivalent was US$145 last time I looked at B&Hphotovideo [ for a B+W product ]

[ajohnw]

I think you are behind the times as I was until recently when I realised that just a two dioptre CU lens would enable a 1000mm AoV lens to give a 1:1 result, even when the sensor is only perhaps 8mm across. A 500mm AoV is getting pretty close but 1000 or 1200 I think kills off the idea that bridge cameras cannot have 1:1..... these days they can

Of no great interest to the DSLR owner with the ability to use extension tubes or bellows.

I find that a 38mm subject filling the sensor meets just about all my needs ... that is a 2D and 430mm AoV ... but need a 4D now with MFT to get similar [ slightly better] with only a 280mm AoV lens. But I have never gone for 'bug-eyes'

On M 4/3 the Olympus 14-150mm wil give around 2.4 to 1 when fitted with the ebay m 4/3 auto extensions tubes. That's 43mm across the 18mm sensor width with the lens set to 150mm. There is plenty of working distance. It will probably give a higher magnification at 100mm and definitely does at 40mm but at that length the working distance is rather short. When I bought the rings some people were selling them separately and others in pairs. I bought a pair but wish I had bought a single 16mm to go with them. With a light lens like the 40-150mm there shouldn't be the flexing problems some have had with Kenko rings on some heavier lenses on dslr's. It's a pity Olympus didn't upgrade this lens in the same way as they did on the 14-42mm which included reducing the minimum focal distance. Minimum focus distance of the 40-150mm is 0.9m. For what it can do this seems to be a cheap option. The extension tubes are sub 30 quid in the UK. Usual plastic body plus metal for mating surfaces.

Going back to the OP's question I recollect that there is an AF problem when using extension tubes on Canon cameras. Not sure maybe some one can comment. It might just be when Canon tubes are used.

John
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[Inkanyezi]

Going back to the OP's question I recollect that there is an AF problem when using extension tubes on Canon cameras. Not sure maybe some one can comment. It might just be when Canon tubes are used.

I think it might be good to return to the OP question, but I'll try to explain the extension tube problems with DSLR, as it might relate in some way to the OP.

DSLR "phase detection" AF systems rely on calculation and tables built into the camera/lens combo. In order not to lose time in focusing, the lens is sent to a particular setting after evaluating the distance between two instances of the same object, something akin to a split image. When this operation has been done, the system signals that the lens is in focus. (I put "phase detection" within quotes, because it has nothing whatsoever to do with phase or phase detection.)

When introducing a distance element between camera body and lens, tables for AF no longer will be correct, and AF will not work properly. As the viewfinder is also difficult to use for finding focus, Live View is the best solution, and contrast detection AF will work.

However, the lens that the OP has is not very suitable for using with extensions, and this goes for virtually all zoom lenses. Extension tubes work best with fixed focal length and with macro lenses. It will also be a viable solution for microphotography with an inverted lens, but then legacy glass with a mechanical diaphragm ring is preferable over the electric lenses for Canon EOS.

So the best ways of getting close-ups of bugs include getting another lens. A macro lens in the region of about 100 mm focal length is a convenient alternative, and a telezoom with close-up attachment lenses is also a possible solution, although maybe not quite as convenient in handling and a tad more difficult to learn. The price of the second solution might be lower.

[Stagecoach]

I guess I'll begin with the close-up filters, then the tubes and perhaps the macro lens. I hope to learn soon!

Just thought I would add this one that is a demonstration of what you can expect to get using tubes on a zoom. I used my 28-105 but note the results if they were to be with respect to the 18-55mm as mentioned in this thread earlier. The magnification ratios are based on my DSLR with a sensor width of 23.6mm

What I can not confirm is the differences between different range zooms but would suspect there's not much difference.

As can be seen working distances are somewhat restrictive up to and at 55mm if you are wanting good magnification.

No 1


No 2


No 3


No 4


Grahame

[ajohnw]

There is a rather long thread on macro shots here

Post your insects

It pops to the top every now and again and sometime stay around for a long time. There is some mention of equipment used in it from time to time.

Personally I would go for extension tubes first as they always may be of use. The achromatic close up filters are rather expensive and even the cheaper single ones are best used on lenses longer than an 18-55mm. The tubes will work well with your lens. Most people buy the Kenko tubes however these days some of the other makes look distinctly similar. The 2 options are opposites after a fashion, close up filters suite longer focal lengths and the effects of extension tubes decrease as the focal length goes up.

Dedicated macro lens focal lengths for general use range from say 85mm to 200mm. There are shorter ones that traditionally were used for obtain greater than 1:1 magnification. That's down to the extension tube / bellows effect. - extensions have more effect the shorter the focal length. A web search might find info on using 24mm lenses backwards on bellows to achieve very high magnification.

As no one mentioned possible problems with AF on Canon cameras using extension tubes a google shows that some are available that do allow AF to function. You might find this of little use at max magnification. It's sometimes better to set the camera up like that using manual focus and then moving the entire camera to achieve focus on the real subject.

When it comes to buying another lens I suspect you will find that a dedicated 100mm macro lens is the cheaper option. From memory when I have asked people who use zooms they have tended to be fast rather expensive ones. Sigma and Tamron used to tag macro on the end of the name as well. They don't do that so often now and where they do the lenses are big and heavy. I would do a lot of research and sums before going down that route.

To give some idea my Canon 70-300mm with 62mm of tubes on using an APS camera gives the following

300mm 40mm field of view
135mm 35mm
100mm 30mm
70mm 25mm

The figures are very approx. It's normal closest focus distance is 1.5m. AF could be a problem unless light is moderately bright due to the F stop reduction.

John
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[DanK]

We have wandered very far from the OP's question. Nonetheless, to pick up on a few points:

The term "macro lens" is just a convention, but it is helpful for people new to the area to clear up the conventions. Manufacturers use the term "macro" in two ways: to refer to dedicated macro lenses, and to mean "relatively close focusing," the latter usually in reference to a zoom lens. As far as I know, very few of the zooms labeled as "macro" are considered to make the cut by most macro photographers. Most of the macro photographers I know use the term "macro lens" to refer to a lens that can reach at least 1:1 magnification. To my knowledge, none of these are zooms. Sometimes they will more charitably include lower levels of magnification, such as the Canon "compact 50", which reaches only 1:2. There is at least one zoom lens that can get better than 1:2: the new Canon EF 24-70 f/4, which I believe can get about 1:1.4 in macro mode at the long end.

Re focal lengths for true 1:1 macro lenses: there are quite a number shorter than 100mm. Sigma makes a 50 and a 70mm. Tamron and Canon both sell a 60mm. (The Canon is an EF-S lens, only usable on an APS-C body). I believe Nikon makes a 60mm with manual aperture control, but I am not certain about that. 60mm is an excellent length for 1:1 macro of things that don't run away, like flowers, if you are using a crop-sensor camera. I have used an EF-S 60mm 1:1 lens for that purpose for years. However, if you are chasing bugs, the extra working distance of a lens in the 90-105mm range (there are lots) is helpful.

Someone above, I think John, suggested an internally focusing lens. I agree, particularly for bugs. All of the Canon macro lenses are internally focusing. I haven't used any of the other brands.

Re AF and tubes: it works with my equipment (Canon bodies with Kenko tubes). It just doesn't work terribly well. The problem is not the design of the phase detection AF system. The main problem is light. Extension tubes effectively spread out the image circle (hence the increased magnification), which means less light captured by the camera, which in turn impedes AF functioning, particularly as the amount of extension gets large. The second problem is that with the razor thin DOF at macro distances, you have very little room for error, and if you don't have the camera on a tripod, your own movement will undermine the AF. As John suggests, you can get more accurate AF using live view, assuming that you have the camera held still. I always use manual focus and live view for tripod-mounted work on subjects that aren't moving. For field work, I often have the camera on a monopod, and I use a mix of AF and camera motion for focusing. For this, you need to have AF moved to a back button so that you don't accidentally trigger it when you hit the shutter. It's nice to have a lens that has full time manual focusing for all of this.

[ajohnw]

I think one extending macro lens has some advantages Dan. This one but for Nikon really if the camera can drive the earlier screw AF-D focus lenses. Off Canon but some Nikon users may be reading.

http://www.photozone.de/nikon--nikko...w--test-report

One advantage of this type on any camera is that as the diameter of the extending part is low there is less likely hood of it blocking light from a camera's in built flash at higher magnification ratio's. The lens is also usually as with the above well recessed into the body of the lens to the extent that a lens hood is unlikely to be needed. I believe most manufacturers have made lenses like this in the past. Used lenses are always an option especially when dealers offer a guarantee. Ebay can be a bit more risky. It varies. Add IS and internal focusing and the size of the lens tends to go up. Especially diameter when IS is added.

There was one person who posted lots of good quality work in the insect thread using a zoom. From memory he used a medium telephoto length macro zoom. Macro on these generally means that they will focus down to 1m rather than something often much longer. Extension tubes and teleconverters are used as well so a large heavy F2.8 lens is needed. These are always rather expensive. The best from memory for this sort of thing was a Tamron 70-200mm F2.8 Macro, might have been to 150mm. Using a converter enlarges the image and adding extension tubes decreases the min focus distance and thus increases the magnification.

As far as dedicated macro lenses go one of the makers produced a 150mm one and that made it rather popular and well rated. There is also the Nikon 200mm, still made new and still rather high priced even old and 2nd hand. Longer focal lengths certainly do attract many keen macro shooters. I think I read on here recently that some one was having problems with Kenko tubes flexing and loosing electrical contact. Probably a big zoom. Some one else had knocked up a bracket so that the camera and lens tripod bushes could be used to gain rigidity. Other people make up remote flash mounts to get round the lens masking the light from the flash. Most people fit diffusers.

The thing that has put me off longer focal lengths and faster glass including zooms is cost and weight. Many cameras need F 5.6 to focus well in reasonable light so an F4 or F2.8 lens is really needed to make use of say a 1.4x converter. An F5.6 lens may not focus at all with 2x on it. Of late some cameras will focus at F8 so things change but over all I think a macro lens works out cheapest, most convenient and it can still be used with converters and tubes as most are F3.5 or faster.

Much shorter than 100mm to me is really for copy stand type work or other situations where a shorter working distance is needed for a given magnification. Actually I would say that is factual as most of the time the shorter working distance would be a hindrance.

John
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