Lens Impression
127判のカメラExakta A型に装着されていたレンズです。bodyのほうはかなりひどく傷んでおり、大修理が必要でしたので、レンズのみ活用することとしました。フランジバックが長いので、ライカマウントにするには大分延長が必要でMS
Opricalさんに依頼しました。宮崎さんのところには様々な延長ヘリコイドがありますので、それほどの大改造にはならなかったようです。ただ、カビ・クモリが多くあったため分解して掃除していただきました。
レンズは補正不足型で、負のふくらみは収差曲線のカーブはローライフレックスのPlanarf2.8と似ているようですが、ふくらみは倍近くあり、よりソフトな描写で後ろボケが膨らむ形です。ノンコートの内面反射と収差でかなりソフトで解像力は低いようです。f5.6でシャープになるが、メインの使用としてはf4前後がバランスがとれた描写。ただ、個人的には開放で使用するつもりです。
It is a lens installed in camera Exakta A type
of 127 size. The body being damaged to be a lot, and major repair seems
necessary, I decided to utilize only the lens. Since the flange back was rather
long, extension was very required to make it Leica mount, I requested to Mr. Miyazaki
of MS Optical. Because he keeps various extension helicoid, at hand, it seems
it became such the shakeup. However, because there were some mold and cloud
inside it, he cleaned it up.
The lens has the negative correction of
aberration, and seems to have resemble curve of the aberration with Planar 80mmf2.8
of Rolleiflex in the shape of negative correction, but level is almost double, which
gives soft description with bokeh in rear is growing. The resolution seems to
be low by considerable software by internal reflection and the distortion of
the non-coat. Become sharp in f5.6,; but description balanced for main use f4
front and back. But I intend to use it by opening personally.
It seems that with internal reflection and
aberration of non coat glass, resolving power is rather low. With f5.6 it becomes
sharp, but as a use of usual main lens, the description is balanced at approximately
f4。But personally, my
intention is using in full open.
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