Stiff card or thin hardboard (mine came from the back of a broken picture frame)
Sheet of paper, preferably 120gsm but 100 will do
2 elastic bands
Drill and bit about 8 - 10mm
And of course a microscope. I use a full size instrument obtained cheaply from a car boot. A children's type will work with this but the image quality and the amount of light getting through leave a lot to be desired.
Step 1: Cut the Hardboard
Put a pencil over the camera lens and slide the phone away, mark the hardboard where the lens is and draw a small circle around it. My circle was about twice the diameter of the lens.
Drill out the circle I used a 10mm drill bit, and tidy up the hole with a little sandpaper
Step 2: Adapting the Microscope
The eyepiece on my instrument is about 2mm wider than the tube (see photo) therefore I had to create a bush so that the adapter sis snugly and will not move.
Measure how wide you need the bush. see photo and cut 3 or 4 strips of paper to this width. Sellotape all the strips together to make a long strip.
Cut a tiny piece of sellotape and attach ot to the end of the strip. Jusr rub your thumb lightly over the bare end of the tape to reduce the stickiness, and attach it to the eyepiece tube, Wrap the paper round once then add a tiny smear of wood glue using the cocktail stick, do this all the way along the strip and wrap it round until the bush is flush with the eyepiece flange.
If you want to wrap a piece of black tape round it later (to make it look pretty) leave the paper strip a bit short so it will be flush when the black tape goes on.
Step 3: Making the Adapter
Measure the width of the paper strip needed for the adapter (see photo) and cut about 4 strips of paper. Stick them together end to end as before and wrap the end round the eyepiece barrel once. Mark where the overlap is and lay the strip down. Smear a drop of wood glue on the strip.
Wrap the strip around the barrel and the glued bit will come in contact with the strip. Wind it round the barrel smearing a drop of woodglue every couple of inches or so until the tube you are making is approximately 2mm thick.
The paper tube will get quite damp and floppy due to the glue. But it will get stiffer as it dries. Be patient.
When its dry enough, move on to the next step.
Step 4: Attach the Ring to the Base
Run a little glue round the edge of the ring and place it over the base, taking care to put it on the correct side. Place the ring so that the drilled hole is as central as you can make it. This is very important. Lift off the ring and youj will see a thin ring of glue on the base. Using the cocktail stick make a nice thick ring of glue. lower the ring into this making sure that the glue spreads up the ring - inside and outside. Build up the glue on the outside nice and thick making sure it's spread well.
This must be left to dry with a light weight placed on top to stop the tube warping as it dries.
Have a cup of tea/ coffee/ beer etc.. The drying time may take a couple of hours.
Near the end of the drying time, when most of the glue has gone clear lift off the weight and dribble a little wood glue over the top edge of the ring, this will strengthen and seal it.
Step 5: Finishing and Using It
Place the adapter over the eyepiece.It should fit snugly with no play at all
At this point I consider my adapter finished. Place your phone on the wooden base lining up the camera lens with the hole and secure with elastic bands. You may want to make a cradle on the base to hold your phone in position. I may do this at some point. Check out some of the photomicrographs I have taken.
Step 6: Tips on Use
Note: if you wear glasses either wear them or take them off when focusing the autofocus will compensate. If you have a fixed focus camera, focus with your glasses ON
In the case of the photo of the parachute seed I have got the light coming up from the mirror and also with a little LED torch from over the specimen giving a little surface detail.
If you have an iris or aperture disc, keep it stopped down as far as you can, this increases the detail and contrast in transparent subjects