Letus 35 extreme, User Manual

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Letus35 Extreme User Guide
7
focus. If it is not, you may need to adjust back focus.
Adjusting The Focus: B.
There are two (2) cases where you may want to adjust the back focus:
Case 1: If your lens
can achieve infinity focus at less than the infinity marking ,
subsequently, the barrel markings are slightly off. This is how to fix it:
Gently loosen the three (3) set screws holding the lens mount. 1.
Remove the lens mount and lens from the tube. 2.
Located on the back of the lens mount 3.
are three (3) small screws. Carefully, one
at a time, loosen each one a small amount.
Each screw should be loosened an even
amount. About 0.2mm may do.
Re-insert the lens mount and attached 4.
lens into the tube.
Tighten the three (3) set screws. 5.
Re-peat the 6.
Testing The Focus step,
checking your focal marks for accuracy.
If yes, you are done. If not, repeat this step until back focus is correct- 7.
ed.
Case 2: If you
cannot achieve infinity focus at all ,
follow this method:
Remove the four (4) Allen Screws holding 1.
the front tube to the body of the adapter
VERY carefully and VERY gently remove the 2.
tube from the adapter. At this point you
should see the Ground Glass (GG) which is
mounted on three (3) Aluminum Posts.
VERY gently, and evenly, pull the three (3) 3.
Aluminum Posts outward away from the
Body about 0.2mm one at a time.
Replace the front tube. 4.
Repeat the 5.
Testing The Focus step.
If you do get infinity focus, then see if the 6.
other markings are correct. If the markings
are also correct, you are done. If you can
get infinity focus but the marking is not
correct, go to the steps in Case 1 to fix it.