Archived posting to the Leica Users Group, 2020/12/27
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Hi Frank, I just received my 7Artisans 50mm f1.1 for Christmas, and it was close right out of the box. I did the calibration yesterday, it took me 3 tries to get it right on. Easy process, but the first time I loosened the screws too much and the ring moved very easily, and too far. But the next 2 times I was more careful. This lens is similar in sharpness to my old 35/1.4 Pre-Asph Summilux. Gene Sent from my iPad > On Dec 27, 2020, at 10:15 AM, Frank Filippone via LUG <lug at > leica-users.org> wrote: > > ?I post this for anyone who now needs or will need this instruction. If > your lens focuses fine, ( the RF focuses correctly) don't fiddle with it. > If it is out of focus, continue. > > This whole process will take you less than an hour. Less if you do not > screw up like I did. > > > Please review this video: https://tinyurl.com/y7cw89lv These are video > instructions from TTArtisan. But the audio is in Chinese (?). > > > What I have posted is a written explanation of how to do it.... Watch it > a few times. > > > My 75 F1.4 7Artisans lens was bought used. I do not know if the last > owner had the lens calibrated to HIS camera or if the lens was not set > properly from the factory. But it needed to be done on my camera. It was > way off. > > Perform this on a bright day where there is lots of light. It makes the > process easier. > > > First off you will need the calibration chart from the manufacturer. ( > Did not get one? Make one up from a piece of paper and an X for the focus > spot, in the middle of the page, and some vertical lines before and after > it. Mount to wall. Tape works, Blue 3M tape will not leave marks or > remove paint. Scotch tape, the clear stuff, WILL remove the paint. Use > clear tape at your own risk!!! > > > You will need the screwdriver for the calibration that came with your > lens. ( Ditto did not get? The proper tool is 0.025 inches or 1mm wide. > Get one off Amazon or eBay) > > Get camera ( I used my M240) and mount lens. Tripod is required. You > want to be 78 inches or so ALONG the wall, and about 45 inches AWAY FROM > the wall to the focus spot. This will create a 30 degree angle from wall > to target X to make the focusing work easiest. You do not need to go > crazy setting this up perfectly. Approximately is good enough. > > > Set lens to WIDE OPEN. This narrows DOF and therefore makes your in focus > evaluation more precise. > > > Focus using your RF to find the correct focus. ( I used a 1.4x VF > magnifier to make things easier. Not required). If you have an EVF > attachment, (the Visoflex) turn it on. If not use Live View (LV) and > check to see WHERE the image of the focus spot is most correct. Is best > focus BEFORE or PAST the focus spot? Remember this relative position. ( > Don't worry how much, this is an iterative process, you will be doing this > several times to get it right.) > > Remove lens from camera. Go to quiet spot with lots of light and is > clean. A kitchen table or countertop is fine. Lens facing upside down so > you are looking at the camera mount side of the lens. > > > The following is what you must do: > > The bottom of the lens has a ring inside. It is black on my lens. It is > inside the chrome lens mount. It has 3 holes...... as far as I can tell, > there are 2 screws in the holes. The third hole has no screw in it. Find > the right holes. Take your finger and hold in place the ring, so that it > does not rotate during the next step. This is pretty important. > The ring moves REALLY easily. > > > Take your screwdriver and GENTLY turn the screws counterclockwise to > loosen it . DO NOT REMOVE IT!!! 1 to 1 1/2 turns is more than > sufficient. > > ( Your finger is holding the ring from rotating, so that you know your > starting place. You can also mark both the ring and the lens mount ring > if you wish, but not necessary. Now that the screws are loose, the ring > can rotate. Go back to which way your lens focused... if it focused PAST > the focus spot, then turn the ring about 5mm or 1/4 inch > (circumferentially) as if you were UNSCREWING a screw (Lefty loosey, > righty tighty). To do this, you will need to loosen your finger grip on > the ring. The ring moves REALLY easily. If you loosen and the ring moves > out of place without your "permission", you just need to tighten the > screws and start over again on the camera, I did it twice. > > > If your lens focuses in FRONT OF the focus spot, you turn the ring > CLOCKWISE. Everything else is the same. > > > Tighten the screws. GENTLY. Apparently, if you tighten too much, it will > affect the lightness of the focusing ring overall. > > > Proceed to mount to your camera, and repeat this process. > > > When you get this right, ( It took me 4 tries) you are done. The lens is > calibrated to your camera. > > If you want to do this with a film camera, the process is the same but you > need to inspect your FILM each time you want to make a correction to the > lens. You can still do it, but it will take you time and a bunch of film > to get right. > > Isn't this easier and more fun than asking Leica to do it? > > Note that I own several of the TTA and 7A lenses. This was the only lens > I have that was not spot on, right out of the box.... new or used. It is > unlikely you will need these instructions. > > -- > > Frank Filippone > BMWRed735i at Gmail.com > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information