My Canon 20D, converted for IR was stolen in Barcelona, so we with Irogoto decided to build new IR camera — from scratch, in hotel room. The day after collecting the parts we were ready to do it. 

Fujifilm Finepix S700 was chosen just because of it's price — less than hundred euros on sale.

So, here are the steps to convert FinePix S700 to IR-enabled camera:

Preparation. Tools and Parts

1. Glass cutter.
2. Optical glass. We bought special objective glass for microscope.
3. Tiny screwdriver.
4. And, of course, the camera.

Herewith soldering iron, solder and cutter will not be nessesary.

Prepare well lit place without dust, make numbered boxes for screws. Or use adhesive tape to stick the screws to it.

Converting S700 for IR is much easier than converting Canon DSLR. You will be able to do it within an hour or less.

Disassembling FinePix S700

step 1

Unscrew 1 and 2 (short ones).

step 2

Unscrew 1 and 2 (long ones).

step 3

Unscrew 1-5. They're different sizes. Screws 1 and 2 are long, 3 and 4 — short, 5 — the shortest one.

Note little triangle with a flash. Fuji is telling truth — it is REAL risk to get electric shock.

step 4

Unscrew 1 (short one).

step 5

Gently lift up back cover.

Disconnect marked ribbon cables. They are flip-type — just flip up the dark lever to release the ribbon cable. Remove LCD.

step 6

Unscrew 1-5 and remove protective shield.

step 7

Unscrew 1 and disconnect ribbon cable 2 (yes, it's flip-type too). Gently lift up the circuit board.

Attention! Don't touch contacts, marked with con the picture! It's a high-voltage capacitor for internal flash, and it can really electrically harm you. Better to put piece of adhesive tape on it during disassembly/reassembly.

step 8

Unscrew 1-4, don't touch ribbon cable.

step 9

Here we are. The reddish glass is the «hot mirror». It is not glued. Just remove it and put on its place a cut-in-advance piece of optical glass with dimensions 9×7×1 mm. Make sure you don't leave dust and fingerprints on glass or sensor. It will be really boring to disasembly camera again just to remove occasional dust particle.

Reassemble camera by following the instructions backward.

NB. Camera will not switch on until you put back the cover.

Filters

The camera have internal focusing system (lens didn't move outside) and screw thread ? 46mm.

I'm using three kinds of filters

1. Cokin Sepia (005) + Cokin ND4 (154). IMHO the best results. Maybe because part of visible light is passed through filters.
2. Cokin ND8.
3. Piece of developed, not exposed E6 film. It's almost completely dark and blokes almost all visible light. But shoots are boring.

In future I'm planing to buy 46mm screw-in filters — sepia, ND and special IR filters (Hoya 93 for instance).

There are "IR-cut filters" on sale — they block IR and after having them screwed into the camera it will operate just like an unmodified one.

There is no sense in placing the filter in front of the sensor. You can't change lens on this camera, so you'll need just one set of filters. And the possibility to change filters will give you much more flexibility.

Finepix S700 notes

• Camera is highly sensitive towards IR. Sometimes you can see white-bright leafs («wood effect») even without any filter.
• Exposure system works pretty good, you don't need ev-correction in most cases.
• There is no problem with focusing, even with a lot thiner glass I used and in f/3.5 apperture the shoots are still sharp.
• No RAW shooting, just JPEG. No special «RAW-enabled» firmware as well.  :(
• Working ISO is not higher that 200. The noise on higher ISO ratios is terrible. And on ISO 1600 the picture is almost useless. But usually in a daylight the speed of the shutter is starting at 1/60, so don't worry — you still can use it without tripod (thanks to internal stabilization system).
• Camera can record IR video. However the white balance setting is nothing other than "auto". The only hope, external editors can solve this problem.
• Camera have 10? zoom lens — something between 28-280 mm (in 35mm eq).
• SD and SDHC cards are used. You can put more than 1000 shoots on one 4Gb card in best resolution.
• Camera powered by four AA-size batteries. The energy is enough to make more than 500 shoots without flash (and who needs flash for landscapes?).
• You can turn off big rear LCD and use tiny LCD in viewfinder. It will save a bit of energy.
• S700 is not speed demon — slow power-on, slow picture writing.

Finepix S700 IR-converted sample shoots