Help with filters, please.

[Vics]

Going through the filters that came down to my with my Dad's Contax IIIa, I find a UV filter, a Y2, an R1, a blue one marked FLASH, a brownish one marked "daylight A" and an orange one marked YA3. My questions are these: How much more exposure do I allow for the R1? What does the YA3 do and how much extra exposure? And just out of curiosity; What do the "daylight A" and the "FLASH" ones do? I'd only use the ones for black and white.

 

[tunalegs]

The daylight and flash filters are color correction filters for use with slide films.

The filters usually will have a filter factor printed on them. This will be a number like 2,3,4 etc. This indicates how much light the filter blocks and serves as a guide for exposure. Once you locate the number, google will do a better job of telling you where to go from there than I can.

 

[Landshark]

blue is for clear flash bulbs and daylight balanced color film.

Daylight A is for type A film in daylight. iDK if there's even an A film made any more.
The easiest example would be the 8mm movie films were type A and the cameras had the blue filter built in
to use the stuff outdoors.

Y2, filter factor around 2 or 1 stop.
YA3, sometimes called deep yellow factor is 2.5 or about 1 1/3 stop.
R1, filter factor of around 8 or 3 stops.

You can increase the exposure by opening the lens or using a slower shutter speed
These are just starting points but should be very close. Some testing would get you on the money.

 

[Rob-F]

"Daylight A" was used with indoor Kodachrome film to convert it for outdoor daylight use. Type A Kodachrome was balanced for tungsten light, which is yellowy. The filter, which is nice yellowy-orange shade, made the rather blue daylight look yellow to the film, so the colors would turn out right. Note this is all in the past tense, since Kodachrome is no longer made.

What to do with a type A filter in the post-modern world? The yellow-orange color ought to make it work as a serviceable contrast filter for black and white shooting. How much to allow as a filter factor? I'll take a wild guess: 1.5 stops?? And bracket from there!