# Macro lens vs Reverse lens



## Syndac (Nov 19, 2007)

First off, I just wanted to say I love this forum.  I'm fairly new here and am quite impressed with the activity and friendly atmosphere, and I've learned quite a bit here already.

I've recently come across some articles praising the technique of mounting a wider angle lens backwards on a camera to produce magnifications greater than standard macro lenses.  I've seen examples of a 24-28mm lens producing results in the area of 4:1 magnification.

Are there any benefits of spending the extra money on a decent macro lens?  I was considering the Sigma 70mm f/2.8 EX DG Macro but after seeing magnifications of 3:1 - 4:1, it makes the 1:1 ratio in the normal macro lens seem inadequate.  I'm interested in the extreme closeups of bugs and stuff because it actually looks quite amazing when a wasp eye fills your entire screen.

If anyone has any experience with either method, please explain the differences.  The reverse mount just seems like it would give better results (greater magnification) at a much cheaper price.  I don't have a 24-28mm prime lens yet, but would consider getting one strictly for macro use unless someone could persuade me otherwise. 

Thanks.

Edit:  Just wanted to add a link to an example of this technique:  http://thephotoforum.com/forum/showthread.php?t=96325
This is actually the thread/website (link in that thread) that got me curious.


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## Skyhawk (Nov 19, 2007)

Hi,

I have both a 50mm and a 100mm dedicated macro lens along with a bellows setup. I can basically get as close as I want with suberb magnification and no vignetting.

Only problem is that dedicated macro lenses are expensive--even the manual focus lenses for plain SLRs.

But macro photography is almost a cult of its own. It's certainly an artform all on its own.

Jeff


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## gizmo2071 (Nov 20, 2007)

*I have not tried reverse macro, this is just from what I've read*

As far as I'm aware, with reverse macro, you don't have control of the aperture. Focusing is simply found by moving closer to the subject until it is sharp (and then if hand held you have to get into a breathing cycle to know when your at the sharpest point). All of the above is true also for MANUAL extension tubes, thoug you can get extension tubes that keep an electrical tag with the lens and you have control of the aperture.
With manual extension tubes it's a good idea to use older manual lenses, where by you set the aperture on the actual lens and not in the camera body, which is a point I am not sure of with reverse lens macro, I don't know if you can set the aperture for it in the lens... make sense that you can.
Another point with reverse macro and/or extension tubes is the focusing distance. You'll be having to get pretty close to the subject and this can make it awkard for:
1) scaring bugs
2) getting good lighting.

If your using a flash, then at such close distances it is hard to get a soft light unless you heavily diffuse the flash and then the angle can be a pain so you may need to bounce it aswell.


Now, with a dedicated macro lens (talking 1:1 or the canon lens that is 5:1, the MP-E65) you have the option of using the AF Servo (if you camera has it), but that would mean your not at your minimum focus distance.
With a dedicated macro lens, especially the 100mm, you have a much larger focusing distance, so you don't have to get to close to the subject and have more options for lighting and a better chance of not scaring bugs.

I personally use manual extension tubes with manual lenses. This is only because I cannot afford a true macro lens.
I would suggest trying macro photography with a reverse ring or extensions tubes and see if it's your thing.Those options are so cheap anyway, it won't matter if you decide you dislike it.
If you really like it, then you have the option to go for a good macro lens.

I'll post a picture of my set-up once my server is back online.


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## Helen B (Nov 20, 2007)

Reversed cine lenses like the Kern Switar 25 mm work well for larger-than-life, when used with bellows. Enlarging lenses work well at slightly less than life size when used forwards and greater than life size when used backwards. I use 75 mm and 105 mm enlarging lenses for macro, as well as dedicated macro lenses. Enlarging lenses are less convenient than dedicated macro (or 'micro' as Nikon calls them) lenses, as already mentioned, but they are very high quality and ridiculously cheap.

The forwards/backwards selection is made so that the lens is working in the manner closest to that which it was designed for.

As already mentioned, the working distance is shorter with short focal length lenses than it is with long focal length lenses. The working distance is determined by the focal length of the lens and the required magnification, but the lens design comes into it as well - which is why a reversed retrofocus* lens gives you a greater working distance than a lens of the same focal length but of normal construction.

Typical wide angle lenses for an SLR are retrofocus, but not all short lenses are retrofocus.

Best,
Helen


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## Garbz (Nov 20, 2007)

With reverse lens you sacrifice control. You loose focus, depth of field, and unless you hack up or buy a professional system to mount your lens backwards, the ability to use both hands to take the photo.

I have played with reverse lens photography for many years, but it was only after I bought a dedicated macro that I begun realising the true potential of seeing the tiny world we pass by. 

The aperture is the biggest issue. IF lens designs when they zoom in close compensate for the light loss without causing diffraction in the normal sense. Mount a lens backwards on a camera and you get a massive drop in light. With a macro the drop in light is accompanied by the ability to extend the aperture (in the case of the 105mm Micro Nikkor anyway) up to f/56 with diffraction setting in at the 30s. So in short without the mumbo jumbo I can get a depth of field larger than 1mm.


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## Helen B (Nov 20, 2007)

When you are using a lens for macro and micro, the indicated aperture will often not be the effective aperture. This has an effect on exposure, depth of field and diffraction.

N' = N (1 + m/P)

Where N' is the effective f-number, N is the marked f-number (ie the f-number at infinity), m is the magnification and P is the pupil magnification.

For a simple macro lens you might have an indicated f-number of f/5.6 and an effective f-number of around f/32. This can make comparisons between lens systems less than simple, unless you are careful to compare effective aperture. True macro lenses like the Micro-Nikkors are not always as they seem: they are not all fixed focal length, and some hold the exit pupil near-stationary, for example. This has an effect of the relationship between the marked f-number and the effective f-number. 

Garbz,

_"So in short without the mumbo jumbo..."_

Please go into the mumbo jumbo. I would be interested to read this*. My experience is different from yours - but as I said in my post above, my choice of normal or reversed is down to the degree of magnification, and what the lens is optimised for - and I probably have a much wider range of lenses for macro and close-up work than most people. I also use what you would describe as a professional system for reversing lenses, though it didn't cost very much (well, one of them came free with my Rolleiflex SL 66 because it is built in to the basic system - one of the great strengths of the SL 66 for macro work)



Best,
Helen

*Edit: As I mentioned in the previous paragraph, many Micro-Nikkors and the like are not easy to compare like-for-like with other lenses because things change as you focus them, so any information would be appreciated.


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## Stranger (Nov 20, 2007)

As i do not own a macro lens, i solely use a reversed 24mm (i used M-A-R-K's setup)

For light, I used the side of a plastic milk jug and cut a hole in it to fit around the lens, and it stands up enough to cover the onboard flash enough to diffuse it.

Using this technique takes a lot of patience because for me, I often have to wait for the bugs to come out enough to a spot where i can get in close (an inch or two away at most) and perform the necessary rocking motions in order to get good focus and not scare the bug. The results can be amazing, but you have to understand that it is a completely different style than normal macro shooting. The DOF is Crazy shallow, (Im talking half a bugs head at times)...

Though i would never use a reversal as a substitute for a true macro lens (because like i said, the style is different) but for me, the 100 i spent for my reversal setup will hold me over until i can afford the 105 micro that nikon offers

http://www.pbase.com/tamar88/larger_than_life
That is my gallery of this technique


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## Neuner (Nov 20, 2007)

Syndac said:


> Edit:  Just wanted to add a link to an example of this technique:  http://thephotoforum.com/forum/showthread.php?t=96325
> This is actually the thread/website (link in that thread) that got me curious.



I've  been practicing with a similar setup except I'm using a 50mm reversed.  It is difficult to get good shots.  My issue is always achieving proper focusing.  Since the DOF is litterally paper thin, getting the part of the insect in focus that you want is tiresome.  It's fun, but takes a lot of practice & patience!

I'd try the reversed lens first & see if you enjoy it.  It's very cheap to do & one of the reasons I gave it a go.  I started off getting a manual 50mm - $15 and a reversing ring - $5.  Can't beat that for a trial!


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## TCimages (Nov 20, 2007)

Syndac said:


> Edit: Just wanted to add a link to an example of this technique: http://thephotoforum.com/forum/showthread.php?t=96325
> This is actually the thread/website (link in that thread) that got me curious.


 
I think it's been explained enough in the other threads. So I will just give an opinion. A dedicated macro lens is the way to go or even extension tubes as they still maintain the electrical connections.  

In the link you provided, I asked in that thread if those images were focus stacked, but he never responded. Given my experience with that set-up, he is doing some amazing work if those aren't stacked. Really hard to believe he is getting DOF like that with a reverse setup, albeit still pretty thin. Good stuff.


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## Helen B (Nov 20, 2007)

When I read that thread I got the impression that he had responded to the question about focus stacking - he said that he didn't do it.

A reversed lens may perform better than a dedicated macro lens at magnifications greater than 1x, so even if you have a proper macro lens, there will be times when reversal is the best option. There's not much point in reversing a lens until you get beyond 1x, except for retrofocus lenses that give you a greater working distance than their focal length would otherwise suggest.

Best,
Helen


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## TCimages (Nov 20, 2007)

Helen B said:


> 1-A reversed lens may perform better than a dedicated macro lens at magnifications greater than 1x, so even if you have a proper macro lens, there will be times when reversal is the best option.
> 
> 
> 2-There's not much point in reversing a lens until you get beyond 1x, except for retrofocus lenses that give you a greater working distance than their focal length would otherwise suggest.
> ...


 
Not sure what you're saying Helen. 

1- What exactly do you mean by perform better?  Also, Why not buy a dedicated macro lens capable of higher magnification if this is the type of shots you want?  The working distance with a dedicated macro lens is much greater.  

2- But how do you get 1x without a macro lens or reversal?


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## Garbz (Nov 20, 2007)

Helen B said:


> _"So in short without the mumbo jumbo..."_
> 
> Please go into the mumbo jumbo. I would be interested to read this*. My experience is different from yours - but as I said in my post above, my choice of normal or reversed is down to the degree of magnification, and what the lens is optimised for - and I probably have a much wider range of lenses for macro and close-up work than most people. I also use what you would describe as a professional system for reversing lenses, though it didn't cost very much (well, one of them came free with my Rolleiflex SL 66 because it is built in to the basic system - one of the great strengths of the SL 66 for macro work)
> 
> *Edit: As I mentioned in the previous paragraph, many Micro-Nikkors and the like are not easy to compare like-for-like with other lenses because things change as you focus them, so any information would be appreciated.



Well what I was pointing at is the general ability to control the depth of field. Every attempt at reverse lens I have tried, stopping down the aperture resulted in vignetting and not an increased DOF. My post retrospectively was very poorly worded but the point was that the dedicated macro lens although it loses light when focusing closely, it still gives you full control over your aperture allowing quite reasonable depth of field, up to almost a few cm at 1:1, where as any attempt at reverse lens photography has not given me this option.

Do you happen to know a way to get adequate depth of field with a lens backwards?


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## Syndac (Nov 20, 2007)

Would using an old lens from a film camera have any kind of negative effects on this process?  I'm not sure how/if the crop factor comes into play if the lens is reversed.


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## Rchang (Nov 20, 2007)

All opinions in this thread are good. The comment I'd like to add is don't try to say which one is better, reverse or dedicated. They have different usage and different pros and cons. 

Dedicated macro lens rarely have magnification larger than 1:1, if not none. If you need higher magnification, reverse or bellow should be the answer, not matter how good a dedicated macro you think. 

Should you need convenient control and take macro image of subjects pass by, take dedicated macro, extension tubes, etc. 

Also, bear in mind that the higher the magnification, the more difficulty in control. That's not the fault of equipment, but the optics nature instead. Yet, it's interesting to explore beyond naked eyes experience.


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## fmw (Nov 22, 2007)

The most important benefits of the macro lens when compared to a reversed normal or WA lens are:

1.  Macro lenses are designed with a flatter field than other lenses.  In other words they are designed to perform better up close.  Virtually all macro lenses will have better center to edge sharpness up close than any other kind of closeup arrangement.  This is the same reason that macro lenses usually don't perform as well at infinity focus as regular lenses, by the way.

2.  Macro lenses will focus to infinity so the range of distances that can be photographed is 1:1 (or whatever the maximum repro ratio is) all the way to infinity.  That makes them more flexible.

Another side benefit is that in this day and age of computer operated cameras, the macro lens will interface with the computer while a reversed lens will not.  That will make the reversed lens not only manual but preset.  Some modern lenses can't work this way and can't be reversed.

In my experience reversed lenses work just fine as long as they aren't zooms and with the understanding that they don't have as flat a field.


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## Helen B (Nov 22, 2007)

TCimages said:


> Not sure what you're saying Helen.
> 
> 1- What exactly do you mean by perform better?  Also, Why not buy a dedicated macro lens capable of higher magnification if this is the type of shots you want?  The working distance with a dedicated macro lens is much greater.
> 
> 2- But how do you get 1x without a macro lens or reversal?



Remember that I am referring to lens reversal in the case of magnifications greater than 1x. 

Any lens is optimised for a certain range of magnifications - in the case of lenses with moving (floating) elements the range can be quite large. Nikon call this CRC (close range correction) and Zeiss call it FLE (floating lens elements). The lens' focal length may also change when focusing. Nikon use it to achieve the ability to focus from infinity to 1:1. 

When you reverse a lens, you invert the magnification it is optimised for. Something that is optimised for 1/10 when mounted normally becomes optimised for 10x when reversed.

The old 105 mm f/2.8 Micro-Nikkor had CRC, but kept the focal length fairly constant, so it would have required a throw of 105 mm to get from infinity to 1:1. It couldn't do that without an extension tube. Once you put an extension tube on a lens with CRC, the CRC gets all out of whack - the floating elements may not be in the optimum position for the magnification. (Some Zeiss lenses have separate focusing and FLE settings to get round this, by the way.)

The current 60 mm and 105 mm Micro-Nikkors reduce the throw necessary to get from infinity to 1:1 by shortening the focal length - the 105 mm is only a 60 mm at 1:1. This means that the CRC can stay in sync with the magnification, because extension tubes are not necessary.

If you want to go beyond 1:1 you will be going outside the range the lens is optimised for. One solution is to turn the lens round. That is why I suggested that even with a dedicated macro lens, reversal may be the preferable option, but it depends on a number of factors, including usability. Nikon happen to make lens reversal comparatively easy, thanks to their huge range of gizmos, and the availability of even the most obscure whotsits on eBay. As I mentioned above, one of the advantages of reversing a wide angle prime made for an SLR is that it is likely to be retrofocus. A reversed retrofocus lens becomes a telephoto (in the optical design sense of the word) that is optimised for greater than 1x magnification - the fact that it is now a telephoto increases the working distance in comparison to a non-telephoto of the same focal length.

I generally use Micro-Nikkors for up to 1:1, Apo-Rodagon-D and D2 lenses at around 1:1, reversed Apo-Rodagon-N lenses for 2x to around 6x or 8x, then either Zeiss Luminars* or reversed cine lenses over about 6x or 8x. I also use Zeiss S-Planar, Schneider Apo-Ronar, reversed Zeiss Planar or Nikkor-AM for medium and large format in the macro range. Of all these, the reversed cine lens setup is the lowest cost, closely followed by the Apo-Rodagons (at least at today's prices). I mention all this because I don't want to give the impression that I consider reversed lenses to be best in all cases. Horses for courses. Sometimes you want the highest possible resolution, sometimes you prefer usability and speed. Many options and many factors.

In many cases for small format I use PB-4 bellows to get shift and tilt - which is useful for close-up work, but it prevents most auto operation.

I'll do some reversed-lens examples using my D40x to demonstrate the degree of field flatness you might expect from a comparatively low cost setup.

* I do not have a complete range of Luminars. They are expensive and they are only optimised for an image conjugate of 250 mm - ie 250 mm from the lens to the sensor or film. Reversed lenses can be the best option for me in this case. That's why I do not have a wide range of lenses optimised for magnifications greater than 2x when used forwards.

Best,
Helen


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