Reverse lens macro photography

I’ve been intrigued by macro photography for a while, but assumed it was the realm of those really skilled people with £10,000 cameras and lenses.  Hayley really wanted a macro lens, so while looking for one to buy her for her birthday, I investigated more, and found that one of the very best super macro photographers uses pretty much home made equipment.  The guy’s name is Thomas Shahan, and if you are at all interested in what spiders and bugs look like close up, look him up.  His photography is simply breathtaking.

http://thomasshahan.com/#photos

Well Hayley got her lens, and it is amazing, but I thought I’d have a go on a shoestring, and see what I could achieve.  There’s a lot of conflicting information on the internets, so I thought I’d do this blog to explain what I have done, the problems I’ve encountered, and what I’ve found that resolves them.  I guess this will be a work in progress for some time, as it seems there is an endless learning curve.

Starting point

What is reverse lens macro photography?  Well, wider angle camera lenses see a wide area, and lenses project that (upside down) onto a small sensor in the camera.  If you turn that lens around, it sees a small area and projects it over a wide area.  A wide area with a small sensor in the middle of it.

Add a set of extension tubes and you have a recipe for some excellent magnification.  I did a wee diagram that I hope explains the theory a bit.

Standard lens arrangement

Reversed lens

Reversed lens on extension tubes

 

Isn’t MS paint great for explaining things!!

You can get fancy extension tubes that maintain the connection between your lens and the camera’s brain, and allow you to use autofocus, but this is utterly pointless if you intend to reverse the lens, as there will be no connection.  A set of basic extension tubes is all you need.  You can get them for around £5 if you shop around on ebay etc.

These are the chaps I use.  there are several parts that screw together, to give a few different lengths of tube.  Just bung them all on.  We are going for major magnification here.

Now you need to mount the lens in reverse.  A reversing ring can be bought off ebay/amazon etc. for a couple of quid.  It has a lens style mount on one side, and a thread on the other, so it screws into the filter thread on the front of whatever lens you choose to use.  So you need to know what filter thread size your lens is.  I am using two lenses, and both have a 52mm filter thread, which is handy.  Actually, at the time of writing I don’t have a reversing ring .  My 50mm prime lens has a UV filter on the front that just happens to fit perfectly into the front of the extension tubes.  Total luck, it just slides in and holds in place.  The reversing ring will be more secure though, and should arrive soon.  I thought I’d just clarify that in case the photos were confusing in this regard.

Seeing the light

The next problem is light.  We’ve reduced the light coming into the lens by turning it round, and shining it on the sensor through a dark tunnel.  We need more light.  We could buy a flash, and for macro ideally a ring flash around the end of the lens, but that costs money. The camera already has a flash, and for subject matter so close to the camera, we don’t need a massive amount of light, just the right light pointing the right way.  The light should also be as soft as possible.

If we use the camera’s flash it will be very harsh, and in the wrong place.  If we are trying to photograph a flower an inch from the lens, then all we get is a shadow of the lens.  I’ve seen various rudimentary solutions to this.  A chopped up milk carton, paper towels hung above the lens to diffuse the light, but I like making stuff, so I built a diffuser that fits on top of the extension tube and channels the flash light to an angled sheet of tracing paper over the top of the lens.  I fitted it to the extension tubes by fitting a cardboard tube around them and building a mount.  It took a couple of prototypes (I sat on the first one!), and a lot of trial and error, but it’s quite solid and robust now, and allows the flash to be popped up and down without it getting in the way, and allows lenses to be swapped without a problem.

Here are some pictures of it.

 

Depth of field and aperture

Macro photography, by any means (except really weird and expensive ones that I don’t understand) generates images with a very shallow depth of field.  This is where an old fashioned manual lens comes into its own. because you can change the aperture without it being connected to the camera’s electronics.  I am using two lenses for this project, a 50mm auto lens and a 28mm manual lens.  The 50mm is one I already had.  It’s a nice lens, but automatic.  When you disconnect it from the camera, it opens right up to f1.8. Reversed and on extension tubes, this gives you a tiny tiny depth of field.  This can be pretty cool for abstract images, but mostly it’s unusable.  The only solution is to set the camera to aperture priority, set the aperture to what you want, hold down the depth of field preview button and remove the lens (without letting go of the DoF preview button). This fools the camera and leaves the lens at the aperture you chose.  Then you need to set up all the other gubbins and take the picture.  Given that a lot of macro photography is trial and error, this is time consuming, frustrating, and potentially not very good for your camera.

One other problem is that reducing the aperture means less light gets in, and below about f7.1 you can hardly see anything through the viewfinder.

However, with a manual lens, you can set the aperture wide open, frame your picture, and then step down the aperture manually to fine tune it.  When you are using a 28mm lens, backwards on extension tubes, it is difficult to even find the subject through the viewfinder, let alone focus, so this technique is very useful.

Taking pictures

Now the hard bit.  Really.  This is like no other photography.  First you need to find the subject in the viewfinder, magnified up to 5 times, with a depth of field of around a millimeter.  Focusing is done by moving the camera/your head back and forth a tiny fraction.  At these levels of magnification, i find that concentrating on breathing helps, taking the picture as you inhale, as you are more steady.  Anchoring your elbows or hands (or even resting the lens on the ground) really helps, as does a monopod if you have one (or a tripod with the legs together).  Take lots of pictures and be prepared to throw most of them away.  The few that work will make it worthwhile.

Results

So what kind of results can you get?  In terms of magnification, I chose the most uninteresting, pointless subject to show the levels of magnification that the technique creates.  These photos are uncropped, taken on a canon 70D.

Picture 1 – taken with a 50mm lens, the traditional way, at the closest distance the autofocus would focus on the jar.

Picture 2 – taken with the same 50mm lens mounted on the extension tubes, but still the right way round.  This is getting close to the 1:1 magnification of a proper expensive macro lens.

Picture 3 – this is the 50mm lens mounted backwards on the extension tubes.  Now we have a magnification of around 2:1

Picture 4 – now the 28mm manual lens, mounted backwards on the extension tubes.  This is giving me 4.5:1 magnification!!

That’s not an insignificant difference!

The opportunities for macro photography like this are endless.  It takes a lot of effort to find magnificent landscapes or rare animals, but we are surrounded by tiny stuff.   I am looking forward to finding some insects to try this out on, but until this point I have been practicing with flowers, watch parts, necklace chains, erm…. salt grinders.  Here are a few images I have taken over the last few days.  I am new to this, and have a lot to learn, so these are my beginner shots.

This is a necklace chain  taken with the 50mm lens reversed on the extension tubes.

These are watch parts, taken again with the 50mm lens reversed on the extension tubes

This is the stamen of a fresia flower, with the 50mm lens reversed on the extension tubes.

Then I took delivery of the 28mm lens, and these are the first couple of images I have managed to produce with that.

A twenty pence piece

The fresia stamen again.  I estimate that this photo is of a subject area of 1mm square. These are individual grains of pollen!

Here’s the lens I was using for these last two photos.

Makinon 28mm f2.8 prime lens.  Manual aperture control.  Pentax fit – the fitting is irrelevant as it is backwards.

Then the light failed me, so I decided to write the blog instead!  I will add more pictures as I go, to try and complete the story a bit.

Problems

So I have a home made flash diffuser, made from stuff I had lying around, but if you bought the materials, probably £10 maximum.  The 28mm lens cost me £9.99 used from ebay, and came in it’s own leather case!  The reversing ring (which I don’t have yet) cost £2.49 from ebay.  The extension tubes (Hayley already had them and gave them to me, as she’s turned to the Nikon dark side) are available for under £10 on ebay too.  So we are talking around £30 for everything I have here.  I don’t expect it to be problem free.

Besides focusing being very difficult, and the lack of manual aperture control on the 50mm lens, there has only really been one main problem, and that is the ghosting on the images. I looked online for solutions to this for a few days, and found very little, until today. Basically, taking pictures of anything bright would create a white haze over the centre of the image.  One of the subjects I have been photographing is a small white flower with a green centre, and the reflection of light from the white petals was ruining my images.  I tried lighting it various ways, including using a continual light from a ring flash as well as the camera flash, but to no avail.  Some sites suggested that it was light leaking into the setup from somewhere other than the lens, or light entering the sides of the lens.  I tried wrapping the whole thing in tape, and making a lens hood, but nothing helped.

Hideous

One review of this method of macro photography on youtube yielded this result and the reviewer just discarded the method as a lost cause.  But having viewed Thomas Shahan’s photos, I knew it was possible.

Then I found an article that suggested making a second aperture ring for the extension tubes.  With reversing the lens, the aperture ring is at the wrong end of the arrangement. It’s pretty much the first part of the lens chain. I guess this results in a lot of light bouncing around inside the extension tube and lens that can get muddled up, and there are various reflective surfaces in there.  It makes a little sense to try to and control this. Another suggestion was lining the extension tube with velvet, but this sounded like a recipe for sensor dust to me.

The second aperture ring still sounded like a bit of a long shot, but I cut out a doughnut shape from the lid of a plastic sweet tub, and stuck it to the inside of the extension tube closest to the camera body.

Bingo, the white haze was eradicated.

Try it

Please have a go at this.  It’s amazing fun, and you can take pictures of things that you cannot see with the human eye.  I can’t wait to find some insects, moths, spiders etc. to try this out on (if the weather will ever behave).

Hayley has her lovely macro lens.  It’s fabulous, and the image quality is quite staggering, but she’s just ordered a set of Nikon fit extension tubes, a cheap 28mm manual lens and a reversing ring.  I guess I’ll be spending the weekend making another flash diffuser!!

I’ll add more photos and info as I learn it.

More examples

Peacock feathers are a terrific subject matter.  I tried combining them with tiny water droplets.

I didn’t think about this in advance, but on reviewing these pictures I was pleasantly surprised by the attractive catchlight shape that the diffuser makes.  Of course, if I’d used a simpler solution like a chopped up milk carton, the reflection would have been far less satisfying.  Sometimes it pays to be a bit OCD about things.

I spent ages trying to capture a water droplet.  The flash freezes it nicely, but the random nature of water means no two drops are the same, so accurate focus is a lottery.  This was taken using a 50mm lens correctly mounted on the extension tubes, so around 1:1 magnification, at f11.

Update

After playing around for several days, and building a similar arrangement for Hayley on her Nikon D3200, I felt that the setup I have created doesn’t quite offer the optimal solution for photography in the field.

One – I found quite quickly that the full extension tube and the reversed 28mm lens offering 4.5 times magnification is too extreme for use on insects.  It’s just too difficult to focus accurately and quickly.

Two – the best setup is the reversed 50mm lens on the extension tubes, offering around 2 times magnification (maybe a bit more).  However, the aperture is not adjustable on that lens.

Three – that setup is quite heavy and cumbersome compared to Hayleys, and the shorter extension tube of her setup allows more light to get to the viewfinder, allowing focussing at a smaller aperture.

So I dismantled mine, and took out the 28mm section of the extension tube.  So I have the camera mount, the 7mm section, the 14mm section and the lens mount, with the 28mm manual lens mounted in reverse on the end.  This is therefore 28mm shorter in length, but offers around 2.5 times magnification.  It also allows more light in, and the aperture is fully adjustable.  I had to build a new mount for the flash diffuser, but I kept the larger diffuser itself, as i like the catchlights it casts.

I think this is the best overall compromise, and offers a complete lens setup that can be mounted and unmounted quickly from the camera.  I also feel that the results are slightly sharper and suffer from less chromatic aberration.

I think this looks and feels a lot neater, and I think it’ll be far more usable out in the field.

Here are a couple of early examples.  Comparing these to the peacock feather images above, I think there is a significant improvement in image quality and sharpness.  The additional light getting to the viewfinder (and the sensor) allowed me to take these at f11 quite easily.

Other things to consider

I have written a couple of separate blogs on specific topics related to this, and will add more over time as I try more things out.

A similar setup for a Nikon camera and the problems encountered

My first attempts at image stacking

And just for giggles

This is what happens when you put a 10mm lens reversed on the full extension tubes, with a handful of step down rings in between.  11 times magnification!!

That’s the T from twenty on a 20p piece.  Getting this image was close to impossible though.  I couldn’t see it through the viewfinder, I had to just guess and take loads of pictures to get one lucky one.

 

 

 

 

 

Advertisement