the model for this tutorial is the OneStep and is the same for all models previously listed. this mod requires removeing the face of the camera and making an adjustment and replaceing the face. 

tools needed: putty or butter knife, pin or icepick.
time frame: 10 minutes.

throughout the procedure, keep the camera faceing upwards

1- open the film bay door.


2-squeeze the top and bottom of the case as shown to create a gap.


3-insert your flat blade as shown and angle out, to lift the face past its clip. repeat on other side.


4-lift face off. you can now see the tabs that hold the face on. one on each side.


5- You are now going to adjust the primary photocell filter, which is preset at the factory.
take a pointed tool, ie, pin, icepick or a hobbyknife and rotate the gear that can be seen to the right of the photocell eye. rotation is counter clock wise or, since the exposed gear is on the right, rotate it upwards until it stops. it doesn't travel far. this sets the primary filter at its lightest possible setting.


modification complete. its now time to put the face back on the camera. with the camera facing up as shown in pics 2, 3 & 4 just drop the face back on. you may notice that the shutter button is on a floating connection, so it may be necessary to steer the button into the button opening, so the face will travel all the way down and the holding tabs in pic 4 seat properly. the view finder may move slightly as well, if it does steer it into position as the face goes back on. your good to go.



600 FILM use in the SX-70 models listed above. there are four protrusions or tabs on the bottom, back side of 600 film carriers. sand or cut off the two outer tabs, or all four if you like, so the film carrier will insert into the camera.

for those of you that would like to know a bit more about what has been done here......................

with inconsistancies through the years of manufacture, constant improvements in the quality of componants and film as well, there was a window left open to calibrate the final product to compensate for these slight variations. as film or componants changed, for production purposes, there was a need to compensate without changing everything in the camera. this adjustment mechanism included a primary, four section density filter, just in front of the photocell, which was calibrated at the factory to offset any of the slight variations.  the four sections of this filter consisted of 8 degrees of filtration, or, a two stop difference per panel. these models were set approximately half way between the second and third panel, or, the middle. 

since 600 film is approximately four times faster than SX-70 time zero film, we are adjusting the filter to change the way the photocell reads light conditions. from the factory setting of the middle of panel two and three, we are adjusting it to where just half of the first panel (lightest) is covering the photocell, resulting in a difference of four stops. its really quite beautiful in its simplicity. here is a pic to show what you have adjusted.