Picture credit score: Lensrentals |
The group at Lensrentals rents rather a lot of digital camera tools. This offers the group an fascinating perspective and gives them with a big sufficient pattern dimension to note if any cameras or lenses usually tend to exhibit sure points. Even good lenses can present issues given intensive use by many various photographers. The Panasonic S Professional 70-200mm F4 OIS is one such lens. It is a well-liked lens that showcases robust efficiency, however Lensrentals has had a few samples with an analogous subject with the autofocus motor failing. Quite than ship the lens off for restore, which might take some time and negatively impacts Lensrentals’ stock, Roger Cicala and Aaron Closz determined to take an affected lens aside and see if they may repair it themselves.
Ranging from the rear of the lens, Cicala and Closz eliminated the bayonet and rear baffle, unveiling some screws to take away and a rubber gasket. The lens is described as weatherproof, however as Lensrentals factors out, there is not any such factor. ‘Waterproof’ actually means ‘weather-resistant.’
Picture credit score: Lensrentals |
After eradicating extra items, they bought to the circuit board. The lens makes use of an array bent flex cables. Apparently, it additionally contains two heavy-duty grounding wires. Lensrentals writes, with a trademark humorousness, ‘I doubt it should affect anybody’s buying determination, however relaxation assured, the circuit board is totally grounded.’
Close to the circuit board, there are a pair of springs arising from the inner optical picture stabilization (OIS) system. The lens guarantees 5 stops of shake correction by way of its stabilization system.
Picture credit score: Lensrentals |
After eradicating further sealing tape and lots of screws, the zoom ring did not wish to budge. It wasn’t going to slip off the again of the lens, so it was time to refocus and begin disassembling from the entrance of the lens. The entrance of Panasonic lenses is usually troublesome to take aside, ‘so alcohol, warmth, and vigorous use of a spudger had been wanted.’ And in case you had been questioning, ‘For these of you who wish to know the way you utilize a metallic spudger with out scratching glass, the reply is expertise. How do you get expertise? You scratch some glass.’
After eradicating the make-up ring and the spanner ring beneath, there’s now entry to 6 screws holding the entrance ring on. There’s additionally sealing foam to assist present a seal towards mud and moisture. Subsequent comes the focusing clutch mechanism, the aperture ring and the focusing ring itself. The lens additionally features a pair of ball bearings, which ‘slot in slots and function rollers when the clutch is moved forwards and backwards to alter from auto to handbook focus.’
Picture credit score: Lensrentals |
After eradicating as a lot as doable from the entrance of the lens, Cicala and Closz moved again to the lens’ rear and resumed taking it aside. Finally, they bought to an uncommon spring. The spring has a small sensor or window or LED. Cicala and Closz aren’t certain exactly what it’s, or if it is answerable for the lens’ autofocus points.
What is that this object? Picture credit score: Lensrentals |
Transferring on, the subsequent component is the OIS unit. It is held in place by thick nylon eccentric pegs and a metallic bracket, which is a design the duo have by no means seen earlier than – and so they’ve seen rather a lot. The nylon pegs alter tilt within the OIS unit. The OIS unit comes out of the lens as complete meeting. After eradicating it, you may see the focusing parts and the lens’ linear focusing motor. Within the picture under, ‘You’ll be able to see the bigger fundamental sliding rod (pink arrow) and the quilt of the secondary sliding rod (inexperienced arrow). The opposite two corners of the focusing group match into plastic corners (yellow arrows) to stop any tilt with motion and each have gentle rubber bumpers to reduce shock on the finish of the main target group’s journey. You’ll be able to see the tops of the 2 magnets on the prime and backside of the focusing group.’
Picture credit score: Lensrentals |
After eradicating extra screws and eventually getting the zoom ring eliminated, we see the inside core of the lens. The core is in two halves, like most 70-200mm zoom lenses. This Panasonic zoom lens contains a thick piece of metallic, which is good to see and speaks to Panasonic’s consideration to element. Some lenses have a weak level right here, which might break. After disconnecting the halves and eradicating extra components, it is time to see what is going on on with the linear focusing motor.
As soon as the electromagnetic coils that run across the sides of the focusing group turn into seen, the issue is apparent. The electromagnetic coils had been hooked up utilizing solely glue to the focusing group plastic and the glue got here free. It was nonetheless hooked up at one aspect, however one aspect is not ok. The focusing group was tilted relative to the motor and was now not capable of transfer nicely, or in any respect. Lensrentals writes, ‘The truth is glue can fail beneath the quick vibrations of a focusing motor. We discovered this type of drawback within the first era Sony and Zeiss linear motor lenses again in 2015. And a few years later we discovered that newer generations of these lenses all put cages, tabs, and many others. to assist maintain the electromagnet in place, they did not simply depend on glue.’
It is price stating that whereas Lensrentals has a pair of Panasonic 70-200mm F4 OIS lenses with this drawback, that is beneath 10% of their whole stock. Additional, their lenses are very closely used. You are unlikely ever to see the difficulty with your personal lens. Nonetheless, in the event you do, do not attempt to repair it at dwelling. It is a difficult disassembly.
There are numerous extra unbelievable photographs from the teardown and intensive particulars concerning the totally different parts of the Panasonic Lumix S Professional 70-200mm F4 OIS lens. If you would like to see them and be taught extra concerning the lens, head over to Lensrentals. We extremely advocate trying out the total weblog publish. It is a treasure trove for lens nerds.