How to set up camera adapters

Words and images by David Clapp.

Two men, one bored afternoon, a steel ring, a rubber glove and some washing up liquid?! I’m out of here! No, you have it all wrong, welcome to my tutorial on adapting manual focus lenses for digital cameras. Learn to adapt and test alternative lenses, bringing manual focus lenses in the digital age.  Get unsurpassable optical results from older optics by following this step by step tutorial.

I am still more than happy with all my collection of alternative lenses in the landscape. Here's the Contax 35-70mm working very happily in -15C.

One of the questions I often receive after proclaiming my undying love for adapted lenses onto my Canon bodies, is how on earth do you set them up so they can perform properly? ‘My lens is soft, this alternative lenses stuff is rubbish’....It's very true to say there are many alternative lens users out there shooting their precious collection very happily without even realising that adapters are not aligned, infinity point is out or worse still the adapter was not manufactured correctly. This article will hopefully add some much needed information about an unwritten subject, to get that excellent alternative glass performing at 110%. All you need is a few household items and an eye for image scrutiny.

Of all the adapters I have set up over the last year and a half of experimenting with alternative lenses, there has been only one occasion where the adapter has worked perfectly without needing some level of adjustment. It was the really expensive one, right? Wrong, it was one I bought for £15 from Ebay. You may be surprised to learn that all the expensive ones I have set up for friends have also required some tinkering, but I am fairly sure this is down to the lens slowly going out of calibration, rather than the adapter itself always being 100% at fault. Herein lies the problem with expensive adapters, is there really any point in spending £140 if it has to be altered to suit your lens? Well, the answer is still perhaps ‘yes’. You are paying for manufacturing precision, high tolerances and quality, but it doesnt guarantee a perfect result I am afraid to say. For that, you have to get more involved.

The Principle
OK, rather than getting too bogged down with the physics of it all, let's look at some common problems with adapters and how to get around them. The principle of this tutorial is to get infinity focus exactly where it is marked on the lens so the lens can perform as it was designed. Just like fine tuning a carburettor, a quality lens will reveal staggering performance, corner to corner, when set correctly, but there are a few problems to overcome. The task is to optimise the lens and adapter so they work together with utter precision.

Some lenses, like my beloved Contax 28mm f/2 are a complicated design. The f/2 has a ‘floating rear element’ (just like Canon TS-E lenses). It relies on perfect alignment of its optics to attain impeccable edge sharpness, which reveals the true magic of this lens when adapted correctly. Adapter inconsistencies and thicknesses cause all manner of subtle problems, but these are the most common problems and how to overcome them -

1. If the adapter is too thick, the lens will never focus to infinity. In my experience this is rather uncommon but does occasionally happen. It is best to return the adapter for replacement. Sanding to reduce the thickness is a time consuming business.

2. If the adapter is too thin, the lens will focus past infinity. This problem is far more common and can usually be altered. Replacement adapters may just highlight a consistant problem - that lens is slightly out of calibration. Not to worry, as the adapter can be adjusted to suit as long as the lens is not too wayward.

Jewellery, Jewellery
Enter David Jackman, a Contax shooter with an enviable collection of superb Contax Zeiss glass. David was about to sell his entire collection and his beloved Contax RTS until a camera club talk I gave convinced him to purchase a Canon EOS 5D to save his beloved glass from the vultures on Ebay. Six adapters and a trip to Devon transcended his entire investment into the digital age. All the adapters except one took some level of alteration, but now David is one very happy man, shooting his high quality glass with confidence once more.

David bought all his adapters from SRB Griturn, here in the UK, on my recommendation. They give an excellent returns policy; if the adapters that don’t work accurately send them back and they will replace them, which is far better than the faceless Ebay approach. The lens we did last from his collection was the Contax 50mm f/1.4, a superb optic with extremely good wide open performance. The problem was the same as the others we worked on earlier - the lens focused past infinity. Here is the method I use to diagnose and alter the adapter, putting infinity in the right place and finalise the results for consistency.

Setting up your adapter - a step by step guide
Make sure you have the following items at hand as you are going to need them all. I have decided to use my 1DsMkIII to set the adapter, as it has Live View which can aid greatly in spotting inconsistencies very quickly. Here is the last one of the batch, a Contax 50mm f/1.4.

You will need - Lens, Adapter, Scissors, Washing Up Liquid, Lens Cap, Sellotape and Electrical Tape.

1 - Attach the Adapter
Put the adapter onto the lens and attach it securely.

Slide the adapter and click it into place.

2 - Attach the lens to the camera
Now attach the lens to the body and ensure the lens stop pin engages. Check the visual alignment of the lens so all the markings are in the right place, just to be sure.

Attach the lens so the stop pin engage and check visual alignment.

3 - Setting Up to Check Infinity Position

1. Tripod mount the camera and choose a simple view that contains infinity. Centre the camera on a bold feature (in my case I use an old wooden gate) aligning this with the centre AF point.
2. Set the lens aperture wide open (in this case at f/1.4) Place the lens at infinity. Setting the aperture wide open, stops the lens pulling the infinity point into focus hyperfocally. This will yield completely inaccurate results so ensure the lens is set wide open as this will ensure far greater accuracy.  You are now ready to test the lens and adapter.

Lens set to Infinity, aperture set to f/1.4.

METHOD 1 - Live View Method Infinity Check - By far the most intuitive way of checking the infinity point, but if you do not have this function don't worry, just skip to the next part.

Engage Live View and recheck the lens is at the infinity mark.

Attach the lens so the stop pin engages and check visual alignment.

Now zoom into 10x and examine the image centre (the gate in this case). Turn the lens away from the infinity position by an absolute fraction, keeping your eye on the gate. Keep turning and checking.   What happens, does it snap into focus as you turn, or does it get worse?

The lens is not working right. The lens focuses past infinity, look at where the true infinity point is, around 1mm out. This is the going to need adjusting.

In the case of David's Contax 50mm f/1.4, that is exactly what happened, you can see where sharp focus is attained. The adapter's going to need some work to make the lens perform properly, but not to worry.

METHOD 2 - Raw File Infinity Check - more time consuming, but it's a good way none the less.

1. With a formatted flash card, Raw mode, set the camera to manual mode and take a quick test shot, checking the histogram for a healthy exposure alone. Delete this exposure in camera.
2. Now check the lens is set to infinity once more. Take a shot. Now move the lens around 1mm away from the infinity point. Take another shot. Now take a few more advancing uniformly and then retire to the computer, download the images and load them into Raw Software.

Reading the First Wave of Raw Results
Result A - If the gate suddenly snaps into sharper focus as you turn (after the first shot for example), say a mm or so away from the infinity point, the adapter is too thin for the lens and needs modifying. No problem.
Result B - If the gate is out of focus but gets even worse as you turn, then the adapter is too thick. Return the adapter for exchange or try another adapter.
Result C - The gate is in sharp focus (sharp on the first exposure) and loses focus as you turn, your adapter is the correct thickness for your lens and camera. Lucky you.
Result D - If the lens is terribly out of focus, it may well be the lens that has severe issues. Consider that fact that the lens is the problem, not the adapter at all. No manner of work will help. I have had two experiences like this.

READ THIS, IT'S IMPORTANT - Adapter Inconsistencies.
Check the LCD or the Raw files further, its very important to clear another issue up - adapter thickness inconsistency. You are also well advised to check the extreme edges of the image, both far left and right. In this case while shooting at f/1.4, the lens edges will look unresolved (in focus but hazy looking). Examine then carefully, you will be able to see if they are in focus or not despite the optical haze.

Result A - if the edges seem uniformly unresolved, then the adapter is machined correctly.
Result B - If the edges seem sharper on one side than the other, then the adapter is badly machined and should be returned for replacement.
Result C - If the edges (not corners remember) seem consistently out of focus either side, you may be experiencing a curve focal plane. Some lenses, like wide angles, have a curved focal plane so those edges will look out of focus. Although slightly unnerving, continue onwards none the less as a curved focal plane is an optical attribute and therefore nothing to worry about.

The Contax 28mm f/2 in full twilight effect. It was complex to set up precisely, but so worth the trouble and remains a firm favourite.

Packing out the lens
OK, on David’s Contax 50mm f/1.4, we ascertained that the adapter needed to be thicker. As the infinity point was only slightly out, I was confident I could ‘pack out’ the adapter to push the lens further away from the camera. It’s a very simple business involving strips of different thickness tape placed between the lens and the adapter (not between the adapter and the camera).

I started by using electrical tape, as it is the thickest and will cause the biggest shift. If this was not enough I could then refine matters by adding Sellotape which is considerably thinner and finally (although I didn’t need it this time) I could use brown parcel tape for the smallest of micro fine adjustment. Often perfect adjustment may only take a single layer of electrical tape, but it is good to know you tweak the thickness to suit your lens and adapter combo in this way.

1. Start by cutting three strips of electrical tape. place them on the adapter at 10, 2 and 6 o’clock. Make sure the tape does not overlap the inside circle but meets flush with the adapters inner edge.

Press down hard with your fingers to make a tight seal. Ensure there are no air bubbles,  or better still use the handle of the scissors and rub the tape so maximum adhesion is achieved.

3.Now take the washing up liquid and put a small drop on your finger.

4. Rub this lubricant sparingly onto the tape sections as this will help reduce friction and slide the adapter onto the lens. By packing out the adapter you will have a harder time getting it to twist into place so reduce the difficulty.

5.Take the adapter in your right hand, carefully slot it into place and begin to tighten it onto the lens. Notice how much stiffer it has become with the extra tape. Not to worry.

6.Take a pair of rubber kitchen gloves and hold the lens tightly as a whole. DO NOT grip the aperture ring with your thumb and fore-finger as it is possible to permanently damage it, place the aperture to f/8 to assure you do not damage it when twisting. Now get the plastic lens cap and tighten it onto the adapter until it clicks into place. The lens cap gives you excellent leverage and makes it far easier to fit the adapter into the right position.

Now retest the lens
Now its time to go outside and check the result by using Live View or the RAW method above. Simply put the lens to infinity, line up the same shot as before and see if things have improved.

1. If the lens is super sharp in the centre you have done it, but remember to check the edges too.
2. Again move the focus 1mm to the right (or an even finer increment like 1/2mm) to ensure that what you are seeing at the infinity position is actually true infinity. I have often found that the packing will need a very small increase, that the electrical tape is just not thick enough.
3. If this is the case get the glove back on, twist the adapter off using the lens cap and apply another layer, this time a thinner application of sellotape.

Cutting sellotape to pack out even further.

After retesting David’s Contax 50mm f/1.4, the infinity point was still very slightly out, so I applied another layer, this time of sellotape. I cleaned off the old washing up liquid I had first applied to maximise the adhesion, then applied the sellotape and reapplied the washing up liquid, sliding the adapter back on carefully. Things were getting very tight, but on the second attempt the adapter slid perfectly into place.

Back outside once more et voila, the adapter was perfectly aligned. Super sharp from side to side, I then began to test the lens throughout the entire aperture range, taking Raw images to examine on computer. We were both very pleased with the results to say the least.

Cleaned and now free from washing up liquid, the sellotape is attached, giving another layer of thickness. This pushes the lens even further away from the adapter, making it even more difficult to attach. Lube up and grab the rubber glove.

Some final thoughts
Now the lens and adapter are performing perfectly, NEVER remove the adapter unless you absolutely have to. You probably wont ever need to, but if you do shoot the same lens on different bodies, then you may want to simply return the adapter back to the manufacturer until you find one that fits perfectly, without the need to pack it out. This may turn into a frustrating and time consuming postal exercise so do consider where you stand.

For most enthusiasts, an adapted lens will remain adapted, so remember to get the technical assessment right, strive for image perfection and get the most out your glorious glass. David literally saved himself thousands of pounds by converting his Contax collection which will continue to pull superb quality images from his EOS 5D for a long time to come. With practise, you will get better and better at setting up alternative lenses, so persevere and take time, don’t rush it.

If you're adapting zoom lenses, check your result throughout different focal lengths. This does take extra time, but the effort you put in at this stage is worth it.

A final note on expensive adapters - my friend Robin had a premium Camera Quest adapter, which surprisingly took some packing work to deliver the unsurpassable quality from his Leica 28mm ROM that he thought he was already attaining. Not so, even for this £150 adapter. Again, half an hour of scrutiny, a few slithers of tape and this truly staggering lens was firing on all cylinders. He was extremely pleased (the lens is sharp wide open at f/2.8 right across the frame), I was extremely envious.

Words and images by David Clapp.