I believe the Auto Tak 55/1.8 has 10mm of helical extension. Anyway, my mouldy old SMC Tak 55/2 has 10mm helical extension and is reputably the same basic lens with a restrictor. If you wound the helical out fully, with a 10mm tube added, you require very slightly less than a stop extra exposure. Without any helical extension the correction is slightly less than 1/2 stop extra.
So you should have been (with the 55mm lens) between 1/2 stop overexposed and correctly exposed. With a negative film that means that you were correct for all practical purposes. If the film is drastically overexposed then its not your technique at fault. If the fault is truly overexposure due to the camera/tube/lens combo, and both lenses showed the problem, I would suspect that the stopdown levers didn't engage all the way through the chain. Either the camera-tube or the tube-lens connection was probably misaligned. Another possibility is that the tube has too much drag in the stopdown linkage for the lens to overcome. As I've recently described in other threads, the lens is at rest at its selected aperture, and the camera holds it at the maximum aperture against its spring tension. When the shutter is tripped (or DOFP operated) the stopdown lever is retracted so that the lens can return to its resting state, i.e. the selected aperture. If the relay levers in the tube were stiff then the lens's lever was either unable to overcome the resistance, or was slowed down enough to still be stopping down when the shutter opened. You can check this by dry-firing the camera/tube/lens combo with a flash connected and the back open or off. Look through the shutter into the lens and you should see the selected aperture lit up momentarily by the flash. If it's wider or fully open, but OK with only the camera & lens and no tube, then the fault will have been found. It might only be a matter of bending a lever to get proper alignment, or lightly lubricating the tube's relay linkage. Check first and you might find it's a DIY job, and avoid the cost of a camera tech. regards, Anthony Farr ----- Original Message ----- From: <[EMAIL PROTECTED]> > > Hi all. > Got my roll of Royal Gold 200 test stuff back.Arggggg.Did something wrong or the film was > old or > bad chemistry at the lab,but somethings not koshur. > Used the SP with a 10mm tube and a 55mm f 1.8 auto tak.Metered with the Minolta spot f and > added 1 > stop for the tube.All of those were terribly over exposed(very dark neg)I switched part > way to the smc > a 70-210 and used the macro on the same subjects.One shot looks correct(but a bad looking > flower) > and again the rest all terribly over exposed.I finished the remainder of the roll on some > rural > buldings,old barns in fields of yellow(mustard??)and the trumpeter swans at the farm.I > shot the > bulidings into the sun a bit and opened 1 stop,on some they are fine,on some the yellow > looks all > mushed together,washed out and the swans i opens up 1 stop due to the sun reflecting in > the water and > they look a bit washed out. > -I quess i did not need to open up on these shots > -expiry date on the RG is april 04 > -i dont remember if i used hand meter or camera meter with the 70-210 > -if the chemistry at the lab was bad,the whole roll would be effected correct > -i just finished a roll of 160vc in the SP and it came out fine. > -seemed to get a big difference in camera readings and spot meter readings > -dropped my Minolta IV F (in its bag)the other day.Can they go out of adjustment because > of that > and if so,can a camera repair place do anything about it. > > Brother Dave(not giving up,just going back to 160vc)Brooks > > >
