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Cold winter is in the air this morning. The first cold front comes down from the Asian Land as usual, Brrr!. Probably temperature outside will not exceed 10 degree celsius today. Though I'm not a reptile, cold weather inhibit me to go outside, a hesitative devil whispers behind my ears, "Cancel an appointment for lunch with my friend. ".
Because of finding out some mold colony in the zoom lens maintained and serviced the other day, I'll disassemble it again on Konica Hexanon 35~70/3.5 2nd generation model.

I noticed that was the case, tens of modified standard lenses are prepared for SONY E-mount after deserting all the camera equipment I had been piling for half a century. My son has the same hobby habit as myself and he gave me some of the second handed SONY E-mount camera bodies one by one, Nex-3, Alpha 64oo, Alpha 7-3 and Alpha 9 as a matter of fact, this is the reason why I am keeping E-mount lenses now even after I had determined to retire from camera and photo hobby a year ago.
As I had modified several Minolta lenses including Zoom ones into Canon EOS mount with 44.00mm flange back distance. Minolta SLR flunge back is 43.50, so Physical discrepancy exists as the lack of 0.50mm distance to establish the definite infinity focusing. Most of the people in the field define that any Minolta SLR lens have no way to modify to adapt another flange connection those exceed 43.50mm.
Some engineer who have experienced to disassembling Minolta lenses should know the critical fact and truth that every Minolta SLR lens has tolerance to establish infinity position and this adjusting mechanical construction covers 0.50mm distance leading to establish infinity on Canon EOS mount with 44.00mm flunge back.
So, tens of Minolta SLR lenses had been modified into adaptation with 44.00mm flunge back, just before the period the period of time, no prevailing of Mirror-less models. Consequently, over 20 of modified Minolta SLR lenses were left unsold behind. Now, K&F Concept EOS/NEX lens mount adapter make it possible to apply them on Sony Alpha 9 by chance, it was a good Gospel for me as a matter of fact.
Standard fixed focus length lenses of 12 pieces in total here are almost from old range finder cameras connecting with Sony E-mount flange base.

It has been several years since I disassembled for cleaning and maintenance Minolta Zoom Rokkor 35-70/3.5 Macro and an actual shooting test and careful checking revealed some poor performance. Consequently, I determined to do that yesterday. Front focusing module was relatively easily removed and the most dirty part exists there invaded by mold. Breathing action caused by the movement of the zooming module invites mold spores let inside this is why this chamber has tendency to get dirty. I applied full overhaul this time including rear condensing module. As for my disappointment, secondary lens from the rear was fixed on the case by means of circular spring wire that might cause uncertainty for precise holding. Unexpectedly, the rear surface of front lens piece of the ilis chamber was invaded by mold attack and several trials for cleaning with solvent were required.
It goes without describe here that the original performance of this cute Minolta Zoom lens was obtained with some surprise, resolution, sharpness and color balance of cleaned one are above words at all, comparable with focus fixed ones.
I should do full overhaul much more earlier before I judge it as an ordinary Zoom lens, not so good one, I feel some shame. I would like to carry this one with me for the time being.
In addition, Web site information told me that the original designing was not done by Leitz GMBh in West Germany but done by Minolta and also production was done in Japan though some of this 35-70 Zoom lens, earlier production without Macro function were produced with different bayonet mount, for Leica-Flex in OEM by Minolta.

I felt that winter is around the corner early in morning today at Hattori-Ryokuchi-Park in Toyonaka, but in the daytime not our butt off. I invited two old lenses, one is Konica Hexanon 45 mm/1.6 originally fixed on Konica EE matic S16, and another is Minolta Rokkor TC-100/4.0, Triplet mountain Rokkor. Both of them were produced over 50 years ago but fully disassembling for maintenance by myself recovered their original fine conditions optically. Color & resolution with sharpness are enough for my use even on Digital Imaging surface of SONY Alpha 9.