- Remove the glass from both the 49mm and 52mm filters if not already done so
- Screw on the 52mm filter ring on the helicoid
- Place 49mm filter on the 52mm filter ring, with female thread side towards the 52mm filter (opposite to each other, see picture)
- Slip the lens onto the 49mm filter ring. Hold them together and mount the loosely packed adapter onto any NEX camera.
- Turn the helicoid to the fully retracted (thinnest) position, and point the camera at a spot that's very far away (infinity focus).
- Adjust the focusing ring on the helicoid. If you can't get a clear picture, the two filter rings together are too thick. You need to get one or both of them with thinner rings.
- If you can focus past infinity by a large margin, get thicker filter rings. The more you can focus past infinity, the longer the minimum focus distance will be. It's ok if focus goes past infinity by a small amount. We are not trying to achieve perfect focus at infinity here.
- If you can't achieve infinity focus with the two filter rings, get thinner filter rings and repeat steps 1 to 6 until you can focus to infinity. I find that with the 17-32mm helicoid, it's much easier to achieve infinity than the 18-33mm. Yes, one millimeter makes a huge difference!
The picture below shows the order and orientation of the filters in relation to the lens. Note the two filters are mounted opposite of each other.
When correctly put together, the adapter should look like the picture below. The 49mm filter should almost disappear into the 52mm filter ring.
If everything checks out and you have infinity focus, it's time to make it more permanent. Please refer to the first picture above for reference while following the steps below:
- Clean the filter rings and the lens barrel with lens cleaning tissue or mild soapy water. Allow the items to dry before proceeding further.
- Mix the epoxy according to manufacturer's recommendations.
- Apply the epoxy liberally to the inner threads of the 49mm filter ring.
- Slip the lens into the 49mm filter ring from the rear of the filter (male threads towards the lens) and push firmly against the filter. Make sure the filter ring is sitting on the lens evenly.
- Apply epoxy on the inner threads of the 52mm filter ring.
- Slip the 52mm filter ring, female thread towards the lens, on top of the 49mm filter ring. The 49mm filter should go inside the 52mm filter. Ensure that all of them are evenly seated.
- Place the lens face down, with the filter rings resting on it. press the filters firmly together on the lens, and ensure they are all seated evenly.
- Mount the adapter on the camera, and rotate the lens until the aperture index is on top and in the middle of the lens relative to the camera.
- Unmount the adapter, making sure you don't move the lens position. Let it set and cure over night.
- With the Yeenon 18-33mm helicoid, the Helios-103 53mm f1.8 lens focuses as close as 0.3m from the sensor, or about 12 inches. Very handy for close ups.
Complete lens with hood. Click for larger.