I found interesting article: Труба Кеплера - макроконвертер и фоторужье в одном флаконе (unfortunately, available only in russian language - it may be feeded to google translate service) and trying to do something similar with lens from old camera. Here is first, quick assembly of two external lens (after test shots i slightly improved this construction: do firm lens placement, better align them and add black tube between two lens).
Both lenses made in USSR for film camera Zenit, which was very popular in Soviet days. Lens (A) - Jupiter 21M, big and heavy telephoto lens, firstly introduced in 1957. It's focusing distance 200mm, apertures 4-22. Lens (C) - my new work horse, Helios 44M-5. I use it (reverse mounted) for both supermacro and superzoom shots with my Canon Powershot A650. These lens were introduced in 1951 and since then have many modifications. They have 58mm focusing distance and apertures 2.0-16.
In this setup, Jupiter 21 mounted in front, with focusing to infinity and aperture set to 4. After it, at distance about 10-12cm placed reversed Helios with focusing to minimal distance and with aperture 2. Directly after Helios placed Canon A650 in maximum optical zooming mode (6x). For focusing, i need to slightly adjust distance (B) between external lenses. After that, Canon autofocusing works fine.
I shoot series of sequental shots (usually 30-60), align them using align_image_stack.exe utility from freeware Hugin panoramic tools. For sub-pixel precision of alignment i enlarge all shots to 500% (5x) with bicubic interpolation, align them, then average stack of shots for better signal-to-noise ratio, and finally shrink it back to it's original size. Averaging greatly helps to get subtle surface details, which cannot be seen in any of single shots (they masked by noise even at minimal ISO). I described averaging process in details in this post.
Shots with this add-on:
pseudo-HDR version with some painting of dark side:
For comparison: two shots without any additional optics (second picture with maximum details i can achieve: clear evening sky, 64 shots averaged):
Author: Alexey Kljatov
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