Right, heres the best way beacuse I feel your pain as no one came to my rescue on this forum either when i started out in alternative lenses 6 months ago -
Take the lens and fit the adapter exactly as it is, no shims just stock as you bought it....
Fit to camera.
Set the aperture to wide open
Set the lens focusing to ~ (infinity)
Go outside your house, find a scene with a view to infinity (like the field opposite my house for instance) and set the centre of the frame to pick out a feature (the wooden gate in the field) Only use the centre to start with.
Starting at the lenses ~ mark take a shot.
Move the focus to just off infinity (lets say 1mm off infinity for instance) Take a shot
Keep creeping the lens and taking shots, around five should do it.
Open the files in RAW software (Capture One is excellent for this as it allows you to see many files open at the same time)
Analysis -
If the adapter is the correct thickness the first shot taken at infinity will be in focus
If the adapter is thinner than required the lens will focus past infinity. Shot number 2 or three will be in focus.
If the adapter is thicker than required the lens will never focus on infinity.
Dont let your eyes deceive you. Its possible even for a f1.4 lens shot wide open to shot good rendition of infinity, even if lacking contrast. If its not in focus, its not in focus. Do not use the off center, edge of the image to check for infinity. These will exhibit lack of sharpness wide open.
Solutions -
If the adapter is too thin, get some parcel tape (thin brown stuff) and some electrical tape. Stick a small length of electrical tape to the table and using a craft knife cut some shims, three to be precise. Unclip the adapter from the lens and stick the shims to the adapter on the lens side, not the camera body side at 2, 6 and 10 o\'clock. Put the adpater back on, it will be much tighter and more tricky to fit. Go outside and repeat the test. If its still not thick enough, undo the adapter and place shims of parcel tape on top of the electrical tape to increase the thickness. Retest and keep going until ~ is where it should be, at the ~ mark on the lens. Now leave this adapter on the lens for the rest of its life! Never take it off again.
If the adapter is too thick, I suggest looking for a thinner adapter. Alternatively you can get the adapter, stick it flat on some wet and dry (fine sand paper for rubbing down paintwork on cars) and carefully thin the adapter by rubbing in circular motions.
Some thoughts -
You will find more than often the adapters are not thick enough. I have an adapter on my Contax 28mm f2 lens that had to be ludicrously thicker than the normal 1.42mm (its never exact from my findings) I had to be 1.54mm, no way could I shim a 1.42mm adapter to that thickness and get the thing on the lens! Its a crapshoot as someone said. No one lens will require exactly the same thickness lens as the rest. All these super expensive adpaters may have better quality chips, aluminium etc but the end result is more than likely you will need to do modification ot the lens if you are to achieve ~ where it is supposed to be. No $250 adapter is the answer. I have adapted 6 lenses and all have el-cheapo £10 adapters bought off Ebay. The only expensive adpater I bought, a Happypage one, is sat on my shelf doing nothing because it was exactly the same as the others.
Just take your time testing out the lenses, the results can be unbelievabe when set up right.
Right, heres the best way beacuse I feel your pain as no one came to my rescue on this forum either when i started out in alternative lenses 6 months ago -
Take the lens and fit the adapter exactly as it is, no shims just stock as you bought it....
Fit to camera.
Set the aperture to wide open
Set the lens focusing to ~ (infinity)
Go outside your house, find a scene with a view to infinity (like the gate in the field opposite my house for instance) and set the centre of the frame to pick out a feature (like a wooden gate in the field)
Starting at the lenses ~ mark take a shot.
Move the focus to just off infinity (lets say 1mm off infinity for instance) Take a shot
Keep creeping the lens and taking shots, around five should do it.
Open the files in RAW software (Capture One is excellent for this as it allows you to see many files open at the same time)
Analysis -
If the adapter is the correct thickness the first shot taken at infinity will be in focus
If the adapter is thinner than required the lens will focus past infinity. Shot number 2 or three will be in focus.
If the adapter is thicker than required the lens will never focus on infinity.
Dont let your eyes deveive you. Its possible even for a f1.4 lens shot wide open to shot good rendition of infinity, even if lacking contrast. If its not in focus, its not in focus.
Solutions -
If the adapter is too thin, get some parcel tape (thin brown stuff) and some electrical tape. Stick a small length of electrical tape to the table and using a craft knife cut some shims, three to be precise. Unclip the adapter from the lens and stick the shims to the adapter on the lens side, not the camera body side at 2, 6 and 10 o\'clock. Put the adpater back on, it will be much tighter and more tricky to fit. Go outside and repeat the test. If its still not thick enough, undo the adapter and place shims of parcel tape on top of the electrical tape to increase the thickness. Retest and keep going until ~ is where it should be, at the ~ mark on the lens. Now leave this adapter on the lens for the rest of its life! Never take it off again.
If the adapter is too thick, I suggest looking for a thinner adapter. Alternatively you can get the adapter, stick it flat on some wet and dry (fine sand paper for rubbing down paintwork on cars) and carefully thin the adapter by rubbing in circular motions.
Some thoughts -
You will find more than often the adapters are not thick enough. I have an adapter on my Contax 28mm f2 lens that had to be ludicrously thicker than the normal 1.42mm (its never exact from my findings) I had to be 1.54mm, no way could I shim a 1.42mm adapter to that thickness and get the thing on the lens! Its a crapshoot as someone said. No one lens will require exactly the same thickness lens as the rest. All these super expensive adpaters may have better quality chips, aluminium etc but the end result is more than likely you will need to do modification ot the lens if you are to achieve ~ where it is supposed to be. No $250 adapter is the answer. I have adapted 6 lenses and all have el-cheapo £10 adapters bought off Ebay. The only expensive adpater I bought, a Happypage one, is sat on my shelf doing nothing because it was exactly the same as the others.
Just take your time testing out the lenses, the results can be unbelievabe when set up right.
Oct 05, 2008 at 07:54 AM
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