Dreamy results from a Helios 44 M7
Were they shot at f1.8? DoF is very shallow
It is two tubes about 3.5inches long, one inside the other, with a T2 fitting on the camera end and a female thread of about 34mm at the other, which is useless. I tried some step ups but it's between 34 and 35mm and none would fit so I couldn't get a lens onto it. I bought a solid looking M42 lens cap off Ebay, screwed it onto a 10mm extension tube and fixed this onto my lathe. I then cut into the flat end of the lens cap to leave an M42 threaded tube and then cut into the inside wall of that tube (the ex lens cap) a fraction at a time until the end of the trombone tube thing would just fit inside it. I secured it with Araldite and left it overnight. Now I have a robust M42 fitting on the end of my tubes. The outer tube has a locking ring so when you've used it - like a trombone slide - to focus, a quick twist secures it. The addition of a focusing helicoid between the tube and the lens could even tweek things further (I leave the lens itself set at infinity).
The Schneider lens is shown simply because it has a helicoid attached. Part of the strange rendering doubtless comes from the
restricted diameter of the tube - compare it with what is potentially available at the camera end. When processing the images
it is necessary to make a huge adjustment to increase the brightness.
It is two tubes about 3.5inches long, one inside the other...
Oh my, that's the kind of job I am definitely no good at at all (mind you, I did completely dismantle, repair and put back together an M28 f3.5 - quite a harrowing experience for me!). What a fabulous set of skills to have - and the results are very much well worth the effort. Thank you for the explanation and the pictures.
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3220 posts
9 years
Slap in the middle of England
The M designation means M42 - there was an equivalent K series too, specifically for Pentax K.
These images are of a strange beast sent to us from China in the guise of Sweet Pea seeds. They turned out to be some
version of miniature vetch which, although having the appearance of sweet pea flowers, are about 4mm across !! The whole
crop takes up a 12inch pot and has grown to perhaps 15inches tall up some netting I gave it for support.
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Taken with a K1 and said Helios lens on the end of about 12cm of tubes, aided by a tripod and IR release.
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