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Tilt and tubes for Macro

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Lens tilt and tubes for macro photography

Using extension tubes with tilt/shift lenses for close up macro work


Tilt shift lenses (aka perspective control lenses) can be very useful once you’ve mastered some of the fundamental aspects of how they can change what your camera sees.

If you are completely new to them, you might want to read Keith’s guide to what tilt/shift lenses do, which gives an overview of the different effects they can give.

Some of the lenses let you focus quite closely and are useful for macro photography. As with many other lenses you can use extension tubes to increase magnification, but how does this work with tilted lenses?

In this short note, Keith shows a few desktop experiments that give an idea of just what you can and can’t do.

tilt and tubes

The equipment

I’m using a Canon TS-E90mm f/2.8L tilt/shift lens on a 50MP Canon 5Ds.

The 90mm focal length and 50cm minimum focus distance gives a useful magnification of .29x (that means the image size on the sensor is 0.29 times its real size)

Higher magnification can be achieved by using extension tubes. The Canon 12mm Extension tube allows magnification of .43x and the Canon 25mm Extension tube allows magnification of .6x

Between the camera and lens I’ve stacked three extension tubes (21/31/13mm) with a total extension of 65mm – think of this as simply being able to focus closer.

tubes and 90mm lens

The tubes have no lenses in them, just some pins to maintain the electrical connection between camera and lens (one reason they are not Canon branded tubes…)

stacked tubes

The lens has been modified from its original configuration, to move the tilt axis and make it a bit more useful for close-up work (simple TS-E90 mod – see my description )

Newer Canon lenses allow you to simply rotate this part of the lens.

The camera is flat on the table, and the big sheet of graph paper lets me mark where the plane of sharp focus is.

To make things even easier, the Camera is connected to my Mac and I’m running Kuuvik Capture tethering software. This is on the big 4k 32″ BenQ SW320 monitor behind the camera. One of the reasons I’m using Kuuvik for this rather than the free EOS Utility software is that it has focus peaking (see later) and split live-view. These just make adjusting the setup a bit easier.

My subject is just a big battery out of a torch – it’s flat and gives a good feel for the idea that the plane of sharp focus is being moved.

Here’s the view of it using the 90mm lens focused at infinity (∞) with no tilt of the lens (purists – please excuse my use of the word tilt, when ‘swing’ would be more accurate)

inf 90mm t0

(click to enlarge images)

Focusing at f/2.8 gives a very thin depth of field – the focus peaking function of the capture software helps here.

90mm focus peaking

Now the shot that will disappoint some people looking to use tilt for macro work.

At near full tilt (7º), look at how much the focal plane has moved.

inf 90mm t7 top

(click to enlarge images)

This is the view from the camera

inf 90mm t7

The curvature of the battery corners is enough to throw the far right of the image out of focus.

You can move the plane of focus, but you are not increasing the depth of field (DOF).

I’d note that without the tubes and taking pictures of things further away, you can get a lot more of the focal plane, but it’s not macro…

This is from my original TS-E90mm review.

ts-e90 product

With 65mm of extension the effective aperture and focal length are increased. I’ll not go into the calculations, but you will need to increase exposure. Fortunately with digital cameras, deciding on exposure is much easier.

When the numbers don’t help

Remember too that when you see a lens marked ’90mm f/2.8′ that these figures are at infinity settings.  If you’d read my article about ‘focusing with tilt‘ you might think that a few simple measurements would give you the numbers to put into tilt tables (or an app) and work all this stuff out.

Unfortunately at closer focus distances, not only do the numbers get harder to work out, the assumptions made about lens design and the like in the calculations, start to fall apart.

All is not lost though – this is why I wrote a second article about iterative focusing with tilt which looks at using tilted lenses close up.

One other effect when using tubes is that the lens focus adjustment has much less effect.

Here’s the tilted shot, but with the lens focus set at 50cm.

50cm 90mm t7 top view

If you enlarge the image you can see the movement of the plane of focus going from infinity to 1 metre to 50cm.

The lens is closer to the subject, so image magnification will change – the lens is not telecentric (see also my notes on making your own telecentric macro lens)

Close-up lens?

From somewhere, I acquired a 58mm +3 close-up lens.

+3D close-up lens

Adding it to the front of the TS-E90 reduces the focusing distance almost as much as the 65mm of tubes.

Unfortunately, the extra glass hits image quality, especially when tilted. Maybe the Canon 250D (+4D) or 500D (+2D) lens is better (see specs for using it later) but I’ve never been that inclined to spend the £100 or so needed for one.

A different T/S lens

Having tested the 90mm, I wondered how the TS-E24mm 3.5L mk2  lens would do (see also my review of this lens from when it replaced my old version).

First up, short retrofocus lenses like this don’t much like extension tubes.

Here’s the focus distance (at ∞) with the shortest 13mm tube.

13mm tube on 24mm

Not so useful…

Fortunately the lens does focus quite closely – indeed I used it in my iterative tilt focus article.

Here’s the lens focused at 25cm (no tubes).

25cm 24mm

Two photos at 0º and 8º tilt (click to enlarge)

Shot at f/3.5 to try and show the plane of focus more clearly (look at the graph paper)

25cm 24mm t025cm 24mm t8

Moving back to 40cm the battery is at the same place as when I was using the 90mm.

Once again the focus peaking can be of help

24mm focus peaking

Two shots at 0º and 8º tilt show how much more tilt of the focal plane you get at shorter focal lengths.

40cm 24mm T0

At 8º the tilt is very noticeable – note the lines from testing the 90mm (click to enlarge).

40cm 24mm t8 top

Interesting effect, with the plane of focus heading off through my desk phone, but hardly macro (click to enlarge)

40cm 24mm tilted

Using tilted lenses for Macro

So, what’s my take-away from all this?

Well it’s that tilting a lens can be an aid for macro work, but if you’re shooting small objects at high magnification then don’t expect to be able to throw the focal plane around with the same degree as you can at ‘normal distances’.

outdoors 90mm

This is from my original TS-E90mm review and shows the ‘miniature world effect’ (something most people quickly tire of, one reason for the good supply of used T/S lenses)

Tilted lenses also lose image quality to some degree and will need stopping down for depth of field and sharpness – once again not so much help if it’s a small living thing you’re photographing.

I actually do macro work as part of Northlight’s commercial photography business, but mostly with lenses like the MP-E65, where I’ll stack photos to get the desired sharpness and depth of field.

An example, where tilt just wouldn’t have got the look (‘making of’ article)

Note that I’m using the 90mm and a 31mm tube (no tilt).

macro photography rig setup

Official notes

With Canon’s original tilt shift lenses, there was this table showing the use of extension tubes and close up lenses

Data is from our EFLens.com lens data for the 90mm

tse macro

New Lenses (Aug 2017)

As I write this, I’m waiting for Canon to launch three new TS-E lenses:

  • TS-E 50 mm F 2.8 L Macro | Shortest shooting distance: 27.3 cm
  • TS-E 90 mm F 2.8 L Macro | Minimum focusing distance: 39 cm
  • TS-E 135 mm F4L Macro | Shortest shooting distance: 48.6 cm

They are all macro lenses with a maximum magnification ratio of 0.5x

Maximum tilt is 10º on the 135mm.

Image quality should be improved on the new lenses, but the fundamentals of optics will still limit the available tilt if you want to work really close (1x for example).

If I get a chance, I’ll be reviewing them in due course.

Here’s the graph paper after my experiments… (click to enlarge)

tilt testing

Any questions – please feel free to email me or ask below?

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