Got my Helios 44-2

[revers]

It is a very nice clean lens without even any dust inside. It came with the "original filter" that we were not able to figure out what it was for from the ad. So here is a shot of it hoping one of you may know from the markings.





Now I am waiting on an adapter to use the lens.

[woodrim]

Close up lens/filter?

[no-X]

I think it could be color filter.

"Г" letter probably stands for "Голубой" which means light blue or cyan. "1.4x" is likely intensity of the filter, the symbol (C letter in circle and triangle) means Lytharino (LZOS factory) and 49x0.75 are parameters of the thread.

[Farside]

no-x is right - the 1.4 is the Filter Factor so you know (on a totally manual non-metered camera) what exposure to use. Multiply your chosen exposure by 1.4.

[revers]

Thanks guys.

It is definitely not a close-up as it only adds a blue colour cast.

" Multiply your chosen exposure by 1.4." I take it then you would use +5 exposure compensation. ??

I will take a couple pics today with & without the filter & post them in this thread.

[no-X]

I think +0.4 exposure compensation should be used (in fact +0.3 or +0.5, because many cameras don't allow to set 0.4 value)

[RioRico]

That looks like a light-blue color-correction filter, something like an 80A or 80C to correct for tungsten light. Back in pre-digital days, color film and filter choices were the "white balance" controls. Such filters are irrelevant on digital cameras... EXCEPT for a special usage I've explored a bit: spectrum slicing.

The most common spectrum-slicing involves IR-pass filters, where we block most visible light, with cutoffs at 680nm or 720nm or 780nm. A violet or blue or cyan filter works at the other end of the visible spectrum. Something like a 47B blue-violet filter might be used with a UV light source for forensics or scientific work, looking for evidence only visible within narrow slices of the visible spectrum. Or, blue filters can be used as virtual time machines -- and therein lies a tale.

The earliest photographic emulsions were only sensitive to 'actinic' light, UV-violet-blue. ALL photo emulsions only see actinic light, UNLESS dyes are added to pass other colors. Such dyes were first developed in the 1870's, for orthochromatic (green-sensitive) emulsions, and panchromatic (all-color) emulsions existed after 1900. If you've ever used a copier where yellow or orange highlighter marks are rendered as black, then you've seen orthochromatic sensitivity in action. Ortho aka 'copy' film is still available, AFAIK.

Time machines? Using a blue or violet-blue filter takes you back to the early days of photography. Look at photos of the US Civil War, and you see that tones don't look 'right' -- complexions are pale, leaves are dark, skies are washed-out. Shooting monochrome, such filters impose the same sensitivity limitations, and also subtly change focus and DOF. I first noticed these effects when I shot slow ortho film in a slow 35mm folder (50/3.5 lens) and noted thin DOF at full-body-portrait range. They looked like 1860's images.

So, a journey into the past. A dark blue or violet-blue optical filter may require a tripod; light-blue filters (like the Russian one above) are better for handheld work. I'll set my Pentax K20D to shoot RAW, then set the Capture Mode to B&W, maybe with Blue or Cyan filtration. I use those settings as the starting point for RAW development in PP. Or I may skip the optical filter and just use the in-camera digital filter to hint at what the optical filter may do -- but as with IR, that's not the same as using the optical filter. Anyway, I definitely get an ancient feel to the tones. And the images definitely need some PP work.

[revers]

[RioRico]

[revers]

Thanks RioRico for your detailed information. Your post must have come in when I was composing mine.

[RioRico]

You're welcome. Filters are fun to re-purpose and manipulate, especially old color-correction filters that are now unwanted and cheap. If photography is literally "drawing with light", then optical filters are like different pencils and chalks. Digital filters just don't give the same effects as colored glass and gels.

[martinsmith99]

FL filters I find useful for just after sunset or just adding a purple cast.