SoC, and is capable to run the CHDK
firmware add-ons.
The A2600 is an old, affordable, somewhat crappy pocket compact camera. It features a very low
weight, fairly small size, runs on a DIGIC SoC, and is capable to run the CHDK
firmware add-ons.
There is no aperture setting in the camera. For higher brightness, the camera can snap in a neutral density filter but that's it.
There is no manual mode. CHDK can alleviate that somewhat - it cannot add the mechanically missing aperture setting but can control everything else.
CHDK can be also controlled via PtP USB,
making the camera controllable from a computer. This way even the display can be made visible
remotely (tested on Windows with chdkptp - the default USB driver has to be replaced with libusb,
use e.g. Zadig
tool for this).
The relatively small lens aperture mates well to a microscope eyepiece; with a bit of optical zoom there is no vignetting. The low weight of the camera may make it feasible to hold the camera to the eyepiece by the lens, without stressing the lens mechanism too much; this will require an adapter.
The lens retracts flush to the case when the camera powers off. This will make design of the lens adapter (for microscope attachment, for attachment of infrared or other filters...) somewhat challenging.
The camera uses a proprietary connector. The A/V and USB functions are merged in a single connector that is compatible with miniUSB but has some additional pins.
The camera has a possibility of external power supply. This is done by a proprietary adapter that replaces the battery. There is a cutout for its cable on the side of the battery compartment, with a piece of rubbery plastic to blind the hole.
There is no in-camera battery charger. An external mains-powered one is supplied by the manufacturer. As such, it is liable to be lost or misplaced. The battery can be however attached to any charger with alligator clips (requires some practice to hold the edge).
The camera accepts the battery even when its middle pin (temperature sensor) is disabled with a piece of tape. This potentially allows running it from a standalone power supply, without having to simulate the battery thermistor with a resistor.
Remove the outer screws. Be aware of the one under the cover of the USB connector.
Flip out the front shell. It is held by hooks at the top side. A subtle force may be needed here, be careful to not break the flimsy plastic.
After removal of the front shell, the back shell can be pulled easily.
The display then can be flipped away. Its connector seems somewhat suspicious, it was decided to not try to detach it. Special care has to be taken to not break the flexible flat cable when the mass of the display dangles on it. Beware of twisting it, the polyimide may tear then.
The controls are housed together on a single flexible circuitboard. The sheet contains the keypad, the top zoom and shutter, the power button, the attachments for microphone and speaker, the focus LED, and the flash module connector. The sheet is secured to the keypad and top support by holes to which the protrusions of the support plate snap into, and with a little piece of doublesided adhesive. Peel it carefully when removing - you will have to peel the sheet off the support plate in order to be able to attach the connector, and then put the support plate in place; impossible when the sheet is attached to the plate.
The black plastic holder of the buttons is attached with tiny plastic hooks. Gently pry them to the side to unsnap them, one by one.
The flash module is a small compact unit. Fortunately it is pretty enclosed, and the capacitor terminals aren't too easily accessible. That thing stays charged for prolonged periods after battery removal and packs more kick than a mule. The module is attached by a single screw to the back plate.
The back plate is attached to the lens module with two screws. One of them was seized and impossible to remove, its head was damaged. A piece of thick wire was soldered to the head and then the removal was easy.
The lens and CCD module is attached by a pair of flat connectors; one goes directly to the CCD sensor, the other one links the two little servos for focus.
The display has to be placed on the chassis plate before reattaching the keypad support plate.
The connector from the control sheet is difficult to reattach. Be careful, and do it before reattaching the keypad support plate. Then reattach the plate, then wrap the control sheet into position and snap onto the support plate protrusions and the doublesided glue tape.
Attempt to not lose the tiny screws, to not mistake the longer coarser-thread ones (that go into plastic) with the shorter fine-thread ones that go into metal.
 Shell removed, front |  Shell removed, front |  Shell removed, back |  Keypad, USB |
 speaker, USB |  Under display |  Under display |  Under display |
 Under display |  Top control panel |  Top control panel |  Top control panel |
 Microphone, LED, flash |  Top control panel |  Top control panel |  Top control panel |
 Top control panel |  Flash power/control connector |  Shell inside |  Shell outside |
 Shell buttons |  Shell buttons inside |  Flash module |  Flash module |
 Flash module |  Flash module |  Flash module |  Flash module |
 Top control panel |  Top control panel |  Top control panel, backup battery and flash connector |  Keypad |
 Keypad, bottom |  Keypad and top panel connector |  Keypad and top panel |  Battery holder |
 Battery holder |  Battery holder |  Battery holder |  Battery holder |
 Inner chassis |  Inner chassis |  Inner chassis |  Inner chassis |
 Electronics with display |  Display |  Display |  Electronics |
 Electronics, battery connector |  Focus motor |  Focus motor |  Battery connector |
 USB connector |  USB, battery |  USB, battery |  USB, battery |
 Electronics, lens |  Lens servo |  Lens servo |  Display, back |
 Electronics, back side |  Lens/CCD and focus module attachment |  Lens/CCD and focus module attachment |  Lens CCD connector |
 Focus connector |  Display connector |  Display connector |  Display connector |
 Keypad and top connector |  Main board connectors |  Main board connectors |  Main board and lens with chassis attached |
 Modules |  Screw position |  Screw position |  How to remove a chewed-head screw |
 How to remove a chewed-head screw |  How to remove a chewed-head screw |  How to reattach a chewed-head screw |  How to reattach a chewed-head screw |
 Screw holes |  Screw holes |  Screw |  Screw |
 Top side with microphone and speaker |  Display wrongly in place |  Display wrongly in place |  Display wrongly in place |
 Display, electronics, keypad |  Keypad and top control foil |  Keypad and top control foil |  Keypad and top support |
 Keypad and top support |  Keypad attached |  Keypad attached |  Keypad attached |
 Front side, assembly |  Front side, assembly |  Front side, assembly |  Back side, assembly |
 Back side, assembly |  Assembled |  Assembled |  Assembled |
 Assembled |