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Mechanical construction of a removable bayonet nail plate and the external infinity adjusting point made me determine to modify Minolta MD 28/2 latest model onto Canon EOS digital formatting image body. The former condition means that the inconvenient extruded part could be eliminated without any grinding procedure avoiding interferences in EOS mirror box, in addition to 0,5 mm backward positioning caused by innate 43,5 mm shorter flange back design. Only 5 screws loosening can carry out the purpose without some troublesome procedures. The latter one does that final infinity helicoid adjustment could be done without disassembling lens element from anterior direction as having been done on older MC lenses mentioned before. The focusing method by moving lens elements is different form ordinary wide angle view lenses, in spite of straight helicoid designing, the frontal lens element rotates while focusing ring is activated? Probably simultaneous movements of another lens module would be happened for some aberration's compensation?

As a matter of another attention, the most frontal glass looks smaller considering F number 2, some newer super transparent glass with lower dispersion material must be introduced in the lens element designing?
A piece of plus headed adjusting screw for infinity helicoid position is fixed by cementing material in addition to 2 small minus headed masked locking screws, approximately 1 mm diameter, 3 screws are designed in total for infinity position adjustment. In order to tighten them and to fix focusing ring onto helicoid outer surface, some experience and skills are required, because too hard tightening torque on them invites some distortion of helicoid construction body, easily distorts leading to heavier rotating movement of focusing ring, so very precise even and adequate adjustment is indispensable for this torque setting procedure.
1 mm left side displacement of helicoid was the position for EOS mount, 0,5 mm frontal position compared with the original Minolta lens flange as the result. Now, setting Minolta lens on EOS mount is established with all attaining infinity focusing, in spite of 0,5 mm shorter flange-back discrepancy.

The purpose for using Minolta MD 28/2 brighter lens on EOS digital formatting image is to enjoy the way of expression on the out focusing gradual transition on the picture, so focusing point infront should be verified accurately through the finder of SLR camera, range finding by human eye is not enough in such situations. This is why I decided to modify it onto EOS using 28mm lens as 35mm one on APS-C formatting imaging area. Thanks to brighter F number of 2, Canon 7D finder commands a fine views when it is attached. So, this MD lens would play and work great with me in future.

Some influence by weather pressure layout brought to Kansai area relatively warm temperature this morning, the end of this year, but a bit rainy outside.
I have succeeded in surviving Minolta W.ROKKOR-SG 28/3,5, an old lens as it had been tens years ago, fully metallic constructive design shows that it would be continued indefinitely if the adequate and sufficient maintenance would be performed. The physical performance might be inferior to recent computer analyzed designed ones, 40 years old has some capability to resolve a scenery with specific character, I can ignore vignetting and circle end peg shape distortions. To tell the truth, I had obtained this one from YaHoo Auction at giving away price, 300 yen! Just because of mold formation at iris portion and heavy focusing ring movement, I knew this 28/3,5 had not been used from the beginning and left untouched as long as 40 years, no wear of straight ahead helicoid guide and the iris ring's clicking movement with moderation, clean and transparent lettering imply the truth. As for critical problem caused by mold breeding inside of lens element, disassembling in pieces and cleaning procedures solved the problems thoroughly like nothing happened in the passed without leaving any scars on coating surfaces.
Denatured and hardened helicoid grease was removed and applied #70 gear oil there instead, re-obtaining desirably smooth movement was reproduced like a new lens. Lens speed 3,5 is not always a good advantage to use it on the see through the lens system with reflecting mirror, because there is some difficulty to find out focused pin point in some darker shooting condition, so this one would not be modified adopting connection by changing bayonet mount keeping Minolta SLR MC and MD mount. I have already obtained 42 PRAKTICA mount EBC Fujinon 28/3,5 as an alternative using by way of 42-EOS adapter. Consequently, SG 28/3.5 lens would be kept as my favorite one so long.

Two Minolta manual focusing lenses from YaHoo Auction arrived at my hand at less than 1,000 yen, MD W.ROKKOR 28/2,8 and MC W ROKKOR-SG 28/3,5 promptly. Though I intended to modify them to adopt onto Canon EOS mount, I have changed my planning to use them on Leica M9 full sized imaging format to enjoy the wide angle optical equipments, otherwise the angle of view would reduced into that of ordinary 35 mm angle if put on APS-C Digital imaging area. Lens internal dirt, mold and dust inviting overcasting if I know these kind of disadvantage does not harm to the shooting result, but I dare disassemble the lens element a part to clean thoroughly, just because it is nothing but my fun.
Also, ZOOM ROKKOR 3,5-105 has arrived at me at cheapest price like nothing, some complicated construction because of adjustable picture angle would make me oblige to make effort to overcome the difficulty leading to my skill-up as an manufacturing engineer as usual.

Early this morning, pedestrian traffic is sparse as the paid work of the government has finished yesterday, though we work till noon and clean all the equipment we have after noon. As a matter for grateful, inconvenient inflammation on right side knee has almost disappeared this morning, because I spent almost of my free time at home yesterday.

I didn't remember the name of a favorite and familiar lens for large formatting image while silver salt film period until I actually ascertain the name plate, Symmar. Out of sight, out of distance, indeed!
I'll make efforts to set the lens on EOS digital format preparing any focusing construction.

I had an opportunity to drive SUBARU BRZ yesterday for the first time without any specific impressions. Though the compliance setting for noise and vibration is excellent, but that of three dimensional swing is not enough, lack of ripening and deeper fabrication, so I felt.

I feel some discomfort in the right knee joint since last evening, probably this dysfunction must be brought out by the lack of body liquid circulation leading to an imbalance of electrolyte in my body as this is often the case of the turn of the year from I was not old. It would take me at least one week interval to recover myself as usual. Failures in hip, knee and leg might lead to a handicapped person with walking difficulty, hoping to make any efforts so that it does not fall on me. Waking capability should be maintained till I go, however old I might be in future. Avoiding overeating, habitual and moderate exercise and correct posture after removing all of the body muscles. I will make good effort to recover myself in 2 or 3 days this time.
Newly introduced SUBARU BRZ for my son came back to us the day before yesterday, I haven't seen it yet, Air-Fighter like cockpit is not my favor?