Description: The digital upgrade kit for the Topcon SL-7E and SL-7F slit lamps provides an attachment and electronic interface for a standard digital SLR camera in place of the original 35mm film attachment.

Photo 1. Digital upgrade kit for Topcon SL-7E slit lamp.

• Bayonet adapter ring.
• Electronic interface cable.
• E3/N3 adapter cable (for cameras requiring the N3 remote shutter connector, such as the Canon models 40D or 50D).
• Hot shoe adapter (for flash synchronization connection on cameras without a built-in PC sync socket, such as the Canon Rebel models).
• Bayonet optional shim (may be needed when upgrading from Topcon MT-1 or MT-2 film camera bodies; not for Topcon MT-10 bodies). This shim is a thin black plastic ring with outside diameter 52mm, inside diameter 48mm, thickness 0.25mm, and 2mm gap at the 12 o'clock position.
• Printed copy of these instructions.

Required equipment:

• Any model Canon EOS digital SLR camera.
• Topcon SL-7E or SL-7F slit lamp.
• Topcon drop-down beamsplitter for SL-7E,7F slit lamps.

Any model Canon camera body is compatible with the adapter. Suggested less-expensive models are the Canon Rebel XTi, XSi, XS, or T1i. These perform well with the adapter. If the camera will be used for conventional photography off the instrument, consider the mid-range Canon line, such as the Canon 40D, which provides sturdier construction and a much better viewfinder. Models such as the Canon T1i and Canon 5D Mark II will also provide high-definition video recording. High-end models like the Canon 5D Mark II are also compatible. Any model camera body, including the least expensive, outperforms the theoretical resolution of the Topcon instrument, so additional camera resolution will not improve the photographic performance.

• Identify the kit components, Topcon equipment, and electronic connector orientation. See Photo 1 above.

• Remove any lens from the Canon camera.

• Attach the bayonet adapter ring to the Canon camera. See Photo 2 below. To identify the correct side of the bayonet adapter ring which mounts on the Canon camera, observe in Photo 2 that the Topcon side of the adapter provides a registration slot in the bayonet ear at the 12 o'clock position. This Topcon side with the registration slot will not fit into the Canon camera.

• Mount the Canon camera on the Topcon beamsplitter bayonet receptacle via the adapted bayonet fitting. Rotate the Topcon receptacle arm down to lock the adapted Canon camera onto the instrument, just like with the old film camera. See Photo 4 and Photo 5 below for the finished installation. A slight rotational play of the Canon digital camera on the adapter is normal.

• Optional shim: If the bayonet adapter locks firmly into the Topcon beamsplitter receptacle, you may disregard this step. If the adapter is loose in the receptacle, insert the optional shim as follows.

  Remove the adapted digital camera from the Topcon beamsplitter receptacle. Insert the optional shim over the receptacle turret, with the shim gap over the registration pin at the 12 o'clock position. Mount the adapted digital camera again, taking care to engage the shim properly around the receptacle turret. The camera should now lock tightly onto the receptacle.

  This optional shim is applicable only to receptacles for Topcon MT-1 or MT-2 film camera bodies, not the Topcon MT-10 type receptacle.

• Detach the Topcon beamsplitter cable connection from the chassis of the Topcon instrument by pulling the connector sleeve back.

• Connect the electronic interface cable from the adapter kit between the two connectors just separated between the Topcon beamsplitter and the Topcon instrument. See Photo 3 below for male versus female connector identification.

• Connect the remote shutter plug from the electronic interface cable to the digital camera body. Use the E3/N3 adapter cable if needed for your Canon model.

• Connect the flash sync cable to the digital camera body. Use the hot shoe adapter if your digital camera does not provide a flash sync connector.

• Turn on the digital camera and the Topcon instrument, and verify that the digital camera shutter operates from the Topcon joystick button, and that the Topcon flash fires from the digital camera shutter.

• Proceed with digital photography. Set the Topcon SL-7E flash energy to its lowest setting. Set the digital camera initially to manual mode ("M" on the mode dial) with 1/20 second manual exposure, ISO 100 sensitivity, and flash white balance. Adjust the Topcon flash energy and/or digital camera sensitivity manually to obtain correct exposures.

Photo 2. Canon digital SLR camera shown with bayonet adapter ring installed.

Photo 3.Male versus female connectors used on Topcon beamsplitter and the electronic inteface cable.

Photo 4. Installation of the digital camera and electronic interface cable on the Topcon beamsplitter.

Photo 5. Side view of digital camera on Topcon beamsplitter, showing bayonet adapter ring.

Additional notes:

• Use the "M" (manual) mode dial setting with a short (or the shortest) exposure time which will still capture the flash (such as 1/20 second).

• Exposure is controlled by setting the ISO speed setting of the digital camera and the Topcon flash energy. Proper exposure is best verified by examining the photo histogram and confirming the general impression of the photo appearance.

• The adapter is designed to be parfocal with the eyepiece view. If your photos are consistently out of focus, check the diopter calibration on the eyepieces and adjust for the examiner's eyesight.

• Canon digital SLRs have one of two types of shutter remote connectors, known as E3 (a 2.5mm subminiature phone jack) and N3 (a three-pin round connector). The adapter is normally supplied with an E3 plug. Use the E3/N3 adapter for Canon camera bodies with the N3 instead of the E3 connection for remote shutter control.

• If using the optional shim to firm up the adapter mounting on the Topcon receptacle, and you wish to remove the digital camera for use off the instrument, it is best to remove the digital camera from the adapter, instead of the camera plus adapter from the instrument, so as to retain the shim in the proper position.