📷 🛠 Helios 44-2 Increase contrast. Partial disassembly. Lubrication. Cleaning the aperture blades. 

Good question. The correct answer is - the one used by the manufacturer. But today, there are many different lubricants, so you can see a lot of variety. The lubricant must have certain properties: not spread, retain its properties for a long time, and so on.

The theory says it should

This is a metal Vernier Caliper s.click.aliexpress.com/e/_DBBBgHx

Yes, of course.

@@xVoLAnD can you post something?I'm curious to know how improves, just to know if worth to do this modification 😃

@@FrankP83 Your request has me stumped. I have no idea how to compare. If you look at other disassembled lenses, you will see that there is something like rubber on the edges of the lenses. Also, you can find information on what is this and what for. That was my idea. You can suggest how I can do that?

@@xVoLAnD I think he was thinking marker on edge edges trick, before images shot without marker applied and after with marker on the edges?

@@muris60 I understand. By eye - it got better, but it's better to have a scientific approach to measure 🤷🏻‍♂️

Это значить, что объектив был неправильно собран. Необходимо разобрать и собрать правильно. У меня была подобная проблема, но с другим объективом, вот ссылка на видео ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ADHV3f_-FRw.html

Это правильно! Так должно быть.

Ас ю кан реад ин азе коментс ай мени таймс ансвер он зис квестшен я не мог придумать как это проверить, но субъективно, картинка получила больше контраста