K.B. Canham  6x17 Roll Film Back Instructions


Congratulations on your purchase of the K.B. Canham 6x17 motorized roll film back.  Following you will find the instructions for use and care of the back to insure that you get the proper performance and use from your new product.

Section 1: How it works

The K.B. Canham roll film back is an automatic drive 6x17 roll film back for use on a 5 x 7 large format camera.  It is a system that runs on one (1) 9 volt battery and is designed to be used with ONLY 120 film. Any 120 film can be used in this unit. 

The K.B. Canham roll film back will allow you to make 6 centimeter by 17 centimeter panoramic images on 120 roll film.  You will get 4 images per roll of 120 film.

With this 6x17 roll film back you have the ability to either manually advance the film after each frame or to a PC connecting cord which will automatically advance the film after the image is taken.  This will be discussed later in more detail.

Section 2:  Understanding your roll film back

The 6x17 roll film back consists of two parts.  The first is the mounting plate (the part that actually attaches to the camera when in use) and the second is the film housing (the part that holds the film when the unit is in use).  To separate the two pieces you need to swing the locking arms 180 degrees in a clockwise direction.  You can identify these two arms by laying the back flat on a table and looking at the top and bottom of the unit Turn each locking arm clockwise 90 degrees. Now you will be able to grab the film housing and lift it off of the mounting plate thereby separating the two. 

The mounting plate is the portion of the roll film back that will physically mount to the camera.  It has only three moving parts.  Two of these are the locking arms that you have just found and used to remove the film housing and the third is the darkslide.  The darkslide is the portion of the back that keeps light from damaging the film while it is in the roll film back.  It is silver in color and is used simply by sliding the unit in and out of the mounting plate before and after exposing each image.  WARNING:  Do not remove the darkslide when there is film in the roll film back unless you are ready to expose an image or you will damage the film due to exposure to light!!!! 
When the darkslide is removed from the back to expose film, handle it with care to be sure it does not get bent or damaged in any way.  This will help to prevent any possibility of a light leak occurring due to a damaged darkslide. 

The film housing portion of the roll film back is the portion where film is held.  This part of the roll film back contains all of the working electrical components.  If you look on the back of the unit you will see two hinges and three doors.  The two doors to the outside are the film chambers that hold the roll of film and the take up spool for the film once it is exposed.  These doors are held closed by tension that is applied to the doors when the film housing portion of the roll film back is mounted to the mounting plate portion.  The third door is in the middle and is the door that leads to the battery chamber.  It is held shut by way of a magnetic lock.  To open the unit simply place your fingernail along the edge of the door near its center and pull.  It should open easily allowing you access to the 9 volt battery plug.  Moving to the top edge of the film housing (this is where the serial number is located) you will find the control center for the roll film back.  Here you will find an on/off switch, a pc plug, a film advance button and 4 small red LED lights. 

Section 3: Using the 6x17 Roll Film Back

The first thing you need to do is to install a new 9 volt battery into the roll film back.  Then be sure the darkslide is securely in place on the mounting plate portion of the roll film back.  Once you have done this you can turn your attention to loading film. 

In order to load film you have to establish which side of the back is the "feed" side and which is the "take up" side.  Looking at the back side of the film housing portion of the back (this being the side where you install the battery) there are two doors.  One door is to the extreme left and one door is to the extreme right, which as was discussed before, are the two film chambers.  The one to the left and underneath the control center is the "feed" side for the film.  The one to the right and located underneath the area where you find the serial number is the "take up" side. 

After removing the film housing from the mounting plate, you can open the door on the "feed" or left side of the back.  Inside there will be two pins, one at the top and one at the bottom that hold the film in place.  Center the film spool over the lower pin and apply pressure in a downward motion.  The lower pin is on a spring so it will sink allowing you to line up the top of the film spool with the upper pin.  When you have done this correctly the two pins will lock the film roll firmly into place.  At this point you should pull the film tab out, running the leader across the front side of the film housing so that the film will cross the pressure plate on its way to the take up side of the housing.  Open the door to the "take up" or right side film chamber.  You can install a take up film spool in the same manner as installing a new spool of film by applying downward force on the lower pin until the top side of the spool is centered and locked in by the upper pin.  You should then place the paper leader into the take up spool.

Now that you have started the film loading process the Canham 6x17 roll film back is ready to be turned on so that the internal motor will advance the "take up" spool.  This is accomplished by utilizing the control center.  Find the control center and look for the button marked "film advance".  Depress this button and continue to hold it down as you move the on/off switch to the on position.  Now release the "film advance" button.  When you do this the take up spool will automatically turn a few times locking the film leader into place.  Now turn the on/off switch to the off position.  At this point you need to close both film chamber doors and place the film housing in place on the mounting plate.  Be sure both film chamber doors are completely closed and securely in place or you risk a light leak that can damage the film.  Upon placing the film housing on the mounting plate, you should lock it down by turning the two locking arms on the mounting plate counter clockwise 180 degrees.

Having locked the film housing into place and having the film leader started on the take up spool you are just about ready to start using the K.B. Canham 6x17 roll film back.  Be sure the darkslide is secure and inserted completely in the mounting plate portion of the back.  Now you can mount the back to your camera.  Turn the on/off switch to the on position once again and depress the film advance button one time.  The back will run for a few moments as the motor moves the film across the pressure plate underneath the darkslide getting the film into position for the first frame.  You will notice on the control center that you now have one red light indicating that you are on the first frame. When you are ready pull the darkslide and expose the first image.  Now replace the darkslide and push the film advance button one time to advance the film to frame number 2.  Notice that you now have two red lights showing on the control center to indicate that you are on frame number 2. Turn the on/off switch to the off position and you can now remove or handle the back without risk of accidentally advancing the film.

**Note:  For the purpose of protecting the image you have taken, we advise you to advance the film to the next frame immediately after exposing an image.  This however is not a necessity to the function of the back and we understand that all individuals have their own preferences when it comes to making their images.  Our best advice at this point is that you find a routine with which you are comfortable and which allows you to keep track of which frame you are on.  Doing this will help to make sure there is neither a risk of double exposure on one frame nor wasting film by advancing the film beyond an unused frame.

As you continue to expose images, you will first have to turn the back on and then depress the film advance button to go to the next frame.  Each time you do you will get another red light indicating the frame the film is on with a total of 4 frames possible on a roll of 120 film.  Upon completing the fourth image you should depress the film advance button one time.  The back will now finish winding the film onto the take up spool.  When it is finished and the film is ready to be removed all 4 red lights will flash simultaneously.  Now you can turn the back off and remove the film.

Automatic advance feature: 
The new K.B. Canham 6x17 offers you an automatic film advance feature that can be utilized to advance the film to the next frame.  In order to use this feature you will need to have a PC connecting cord to run from the roll film back to the lens you are shooting with.  To utilize this feature you must first follow the steps listed above to get the film to frame 1 so that the back is ready to use.  Once it is set up and ready, you can use a PC cord to connect to the PC outlet which is located on the control center portion of the back just to the left of the on/off switch.  With the PC cord connected and attached to the lens, the roll film back will automatically advance the film to the next frame once you have exposed an image.  There will be a two second delay from the time you trip the shutter to the time the film is advanced. It is therefore necessary to use shutter speeds of one second or faster.  (If you are using a lens with a very old shutter, make sure that it is set on X sync.)  When you have exposed the fourth and final frame the roll film back will pause for a few seconds and then will advance the film through the back to the take up spool so that the film is ready to be removed from the back. 

Section 4:  Additional information and specifications

If at any time during use the back gets jammed, the four LED lights will flash in a random pattern. Based on our tests we estimate you will be able to shoot 35 rolls of film through your back before having to change out to a new battery; however this can vary based on the brand, age, and type of battery you are using.  The back has been programmed to indicate a low battery. The first two LED’s will alternately blink when the battery is dangerously low.  To avoid this problem we advise you always use a new, fully charged 9 volt battery.  

If at any time you are experiencing difficulties with your back or if you have further questions that are not answered here, please contact the dealer who sold you the back to obtain the assistance you require.


Film:                               120 roll film only
Battery:                           9 volt
Weight:                            approximately  2 lbs.
Dimensions:                     centimeters=14.9 x 23.8 x 4.9 
Frames per film roll:         4
Rolls of film per battery:   approximately 35
Image area:                     168mm x 56mm