Which KR and KB filters do I really need?

[Puma]

Hi,

I'm venturing into the world of color and would like to know which mired filters I really need to own to shoot outdoors and indoors with 5500 Velvia 50 and Portra 800.

I understand the theory behind the use of them, but have never done it. Are there filters that you're constantly reaching for? Some you never use?

Thank you,

Puma

 

[Tim Gray]

How are you printing? Traditional or by scan? If the latter, we won't have to discuss the details, but suffice to say, a film like Portra 400 or 800 can get away with less filtration than normally needed since you can adjust the layers in ways that are hard to adjust in an enlarger.

That being said, for 'proper' filtration, you probably want a filter that goes from 3200K to 5500K, i.e. 80A. Mind you that most interior lights are not at 3200K, but something lower like 2800K, or worse, tungsten/daylight balanced fluorescents with low CRIs. On the other hand, and 80D filter really eats up the light. When I know I'm shooting a lot in tungsten lighting, I use a KB6 filter (like an 80D I think). It's a half correction, from 4400K to 5500K. It brings out the blues a bit and you only lose 1/2 a stop.

For fluorescents, I've never corrected them with a filter. You want some form of minus green, but it's kind of a crap shoot as to what strength you need since the fixtures can be all over the place. Hopefully you are shooting in high CRI lighting. That being said, it's my personal opinion that Portra 400 handles mixed lighting (fluorescents AND tungsten) much better than Portra 800.

For Velvia, or other slide films, you probably want the proper correction, i.e. an 80A. I can't imagine shooting that film in Tungsten lighting through an 80A. That'd be exposure index of 12...

It's a shame Kodak doesn't sell something like Vision3 500T for still cameras. That'd be awesome.

 

[Puma]

Thank you for the info!

I find that the mixed values of the mired versus the Kodak are extremely confusing. I'm going through the filters to buy right now and sometimes the b+w's are listed in mired (KB6) and sometimes kodak (80A. etcetera) and I can't seem to find a chart that makes sense of it all. I'm planning to stick to the mired values for my work for simplicities sake.

I'm planning on doing all of this in the darkroom as soon as I can find a color module for my V35, should you know the whereabouts of one I would greatly appreciate it. I tried a hybrid workflow and was extremely disappointed with the results and anyway I hate computers and have no desire to sit in front of one any longer than I have to. I'm also excited about processing my own color negatives and positives and getting a chance to experiment and really learn something.

While we're on the subject, do you think the MRC multi coated are worth the extra expense? Or should I just get the regular ones?

Thanks.

Puma

 

[Tim Gray]

I think you can pretty easily correct for discrepancies in color temperatures on an enlarger if all of the light in the image is the same color temp, ignoring some color crossover in the shadows/highlights (which might not be too bad). You will run into problems if you have low CRI fluorescents mixed in with daylight or tungsten. Again, I've found the Portra films to handle tungsten lighting pretty well and mixed daylight/tungsten environments.

As far as MRC goes, with the exception of one lens, all of my lenses are either 39mm or 46mm. And my main three lenses are 46mm; the 39mm lenses don't get used anywhere near as much, and rarely with filters. So, I've been building a nice set of 46mm filter that I share on my lenses. As a result, for the extra $10 for MRC, I get it. If you want to collect them all in a bunch of different sizes, then maybe don't spring for the MRC.

Here's a link on Wratten numbers. The 80 and 85 series are the workhorse for color temp conversion.
http://en.wikipedia.org/wiki/Wratten_number

I also find the B+W filter handbook to be a nice resource for filters:
http://www.schneiderkreuznach.com/pdf/filter/b+w_filter_handbook.pdf

 

[2F/2F]

I don't really know how mired filter values work, but I can answer your question in terms of Wratten #s.

I find the following are ones I am "always reaching for:"

1. 80A - For indoor shooting mostly. Because the main type of artificial light that I use for shooting things indoors is 3200K Photo Floods. I also use it for shooting night cityscapes on daylight film. No filter is perfect for that purpose (mixed artificial lighting), but it helps a bit with those orangey street lamps (are they "sodium vapor?) and peoples' windows, porchlamps, etc.
2. 81A - General purpose mild warming filter. If it is convenient, I will use it outdoors if the weather is patchy (can make for blueish pix). I also use it with the 80A and Photo Floods sometimes for a little more warmth.
3. 85C - I don't use this to use tungsten film outdoors, but to compensate for very blue light, like any time that the blue sky is the main light (e.g. in open shade). It helps a lot when printing neg film, though most people would say it is only a necessity with transparency film.
4. 82A - I use it stacked with the 80A when using household bulbs instead of Photo Floods.
5. FL filter - I haven't used it in a while, as most fluorescent lamps I encounter seem to be closer to daylight balanced now. But I used to use it a lot for shooting inside various locations. It is a PITA to print if you also have a window in the frame, though. Requires split filter color printing, which is a nightmare to me. If you end up with a blue window when correcting for tungsten indoor light, it can look OK, and vice versa. However, a pink window when correcting for fluorescent light is pretty ugly.

This being said, I don't really monkey with the filters that often unless shooting on a tripod with plenty of time. But if shooting negative film, I do give an extra stop or so of exposure in "off-colored" light if possible. This assures that all the color layers get enough exposure to properly balance the film across the entire tonal range when printing.

 

[Michel Hardy-Vallée]

Start by reading the B+W filter handbook: http://dl.dropbox.com/u/8959/b+w_filter_handbook.pdf

Be careful, the new filter handbook on Schneider's site does not include colour balance filters anymore. The old handbook is still there if you Google it.
Old: http://www.schneiderkreuznach.com/pdf/filter/b+w_filter_handbook.pdf
New: https://www.schneideroptics.com/pdfs/filters/B+WHandbook.pdf​

At pages 18-19-20-21, you will find the description for their range of KB+KR filters. Notice that their KB filters are equivalent to the Kodak/Wratten series, but for the KR filters, the Kodak/Wratten 81 filters have a different spectral response, and are not equivalent.

You can check the transmission curves at the end of the handbook to understand better their differences.

On page 64-65 you will find a chart to help you figure out which filter you need if you go from situation X and film type Y and want to achieve result Z. These charts are very common, and you can also find them in Kodak Master Photoguides (the blue ones) in the form of a dial calculator. Useful if you have 80-series filters instead of the decamired filters.

In practice: I personally use at least a KR1.5 or 2 filter on all colour shots I take outside, since there is always some blue from the sky washing off the colours. Lately, I've been using a stronger 5 filter for those blazing cloudless days, and on Ektachrome 100G, it was worth it. A stronger filter such as the 11/12 conversion filters is too much for subjects not entirely in the shade.

When inside and shooting with daylight film, remember that even a full conversion filter is not enough to remove the red component of ordinary tungsten bulbs. "Tungsten" refers to photolamps and halogens, and if you want to filter out an off-the-shelf bulb, you will need a full conversion filter + extra filtration.

I personally don't shoot inside much, so I haven't used the blue filters much.

 

[Michel Hardy-Vallée]

It's a shame Kodak doesn't sell something like Vision3 500T for still cameras. That'd be awesome.

If you dig around the APUG forums, there's been some discussions lately about services selling ECN-2 films in canisters, and printing them as slides on ECP-2.

 

[Tim Gray]

If you dig around the APUG forums, there's been some discussions lately about services selling ECN-2 films in canisters, and printing them as slides on ECP-2.

Yeah. I actually have two rolls of 500T that I was sent from someone on APUG. I need to use them and try out the one lab in Ohio. It's just a shame there's not a C-41 500T.

 

[Michel Hardy-Vallée]

Yeah. I actually have two rolls of 500T that I was sent from someone on APUG. I need to use them and try out the one lab in Ohio. It's just a shame there's not a C-41 500T.

I tried some 64T Ektachrome over the winter holidays, and I was pleasantly surprised by the delicate warmth it had when used with ordinary tungsten. It cut off most of the extra red, but left enough to keep the mood.

I would love to shoot more tungsten film, but in my case it never seems that I spend enough time inside to even consider using a whole 12 exp of the last readily available films. Although I could see its value in museums/galleries: at 500T, you can take really nice pictures of artwork without bothering with flash.

 

[Tim Gray]

I shoot a lot of stuff indoors, so 500T would be sweet. Also, for outdoor stuff, you could throw on an 85 and only lose a little bit of speed, so I'd get by with it there too.