The 86mm Decamired Blue 1.5 Cooling Filter from Tiffen is for those who want a sure-fire way of getting accurate color temperature readings. Using this formula, you can transpose temperatures from one point to another easily and quickly. This system is also useful when you wish to bring a certain amount of creativity to color photography.

Decamired filters are used to maintain consistent color temperature during the day's shooting. Decamired filters are available in two series - reddish filters that warm the light and bluish filters that cool the light with each series available in four densities: 1.5, 3, 6, and 12. When filters from the same series are used, they can be combined.

Decamired filters can be readily combined to create almost any required color correction. In measuring the color temperature of the light source, and comparing it to that for which the film was designed, required filtration can be easily calculated.

A filter that produces a color temperature change of 100K at 3400K will produce a change of 1000K at 10,000K. This is because the filter relates to a visual scale of color. It will always produce the same visible difference. A color change of 100K at the higher temperature would hardly be noticed.

Calculations
To use this concept, subtract the mired value of the light source from that of the film. If the answer is positive, you need a reddish filter; if negative, use a bluish filter. Mired-coordinated filters are termed as decamireds. Mired value divided by ten yields decamireds. The 60 mired shifts, above, would be produced by an R6 filter, where the higher values were that of the lighting.

Sets of such filters generally come in values of 1.5, 3, 6, and 12 decamireds in both B (bluish) and R (reddish) colors. These numbers are additive; that is, a pair of R3's produces an R6. An R6 plus a B6 cancel each other out to produce a neutral gray.

Used for Accurate Temperature Control    Filters Can Be Combined to Control Color    Made in Specific Increments    Available in Warming and Cooling Variety    ColorCore Glass    Made in the USA    10-Year Warranty

The decamired system has an advantage over the Kelvin system in that the Kelvin scale is not linear

Decamired readings provide more accurate/controllable readings than Kelvin

The difference between the Mired value of the film and the Mired value of the light is the Mired value of the correction filter that correctly balances the light to the film

Related Questions and Answers

Q: 1. Does this lens work with the Leica M (digital body)?

A: Yes. This is an M mount lens.

Q: 2. Any difference between this lens and Zeiss 50mm f/2 ZM Planar??

A: There are considerable differences between the two lenses. The C Sonnar 1.5/50 ZM is a classic lens design from the 1930's. It renders a sharpness that is slightly rounded, being less aggressive than in contemporary lens designs, but at the same time not soft in its rendition. Many famous portraits of glamorous and prominent people during the 1930s used this technique to great effect.This lens design exhibits some additional effects, which should be understood to achieve the maximum benefit. The best focus position in the object space cannot be kept exactly constant for all f-stop settings. The photographer might notice a slightly closer best focus in his pictures than expected. When stopping down the lens to f/2.8 or smaller this effect is minimized, so the focus position will be as expected. The special features of the C-Sonnar 1.5/50 ZM are best used in emotional, artistic, narrative images, portraits or atmospheric landscapes. For documentation or technical subjects, ZEISS recommends to stop down the lens at least to f/5.6 or to use the Planar T* 2/50 ZM lens.

Q: 3. Do 50mm frame lines show in viewfinder of M3 and M6 with this lens?

A: Yes, the Voigtlander Nokton 50mm f/1.5 Aspherical Lens will bring up the correct 50mm frame lines in the viewfinder for Leica M series cameras.

Q: 4. Can a lens like this be adapted to be used on a canon eos 5d M3?

A: Unfortunately, no. Due to the differences in focal flange distance, there are no lens adapters designed to connect a Leica M-mount lens to the Canon EF lens mount which is used on the Canon EOS 5D Mark III DSLR camera. The focal flange distance of the Leica M-mount is 27.8 mm, which is smaller than the 44 mm focal flange distance of the Canon EF lens mount. A Leica M-mount lens would not fit and would not have the ability to focus to infinity on the Canon EF lens mount.

Q: 5. how does this handle in low light ? can you recommend any leica m mount to fuji x mount adapters ?

A: The lens is a manual lens. It does not support autofocus. It is f/1.5 so very good for wide open shots. And for a Leica M mount ot a Fujifilm X mount adapter this is a good one but is fully manual. FUJIFILM M Mount Adapter for X-Mount Cameras BH #FUMMA • MFR #16267038 https://bhpho.to/3uwnNuJ

Q: 6. Can the aperture ring be declicked for smooth iris control?

A: No it cannot.

Q: 7. Hey guys, is this full frame ? Thanks.

A: Yes

Q: 8. Can B&H arrange for the recalibration of the focus to wide open at 1.5?

A: Not that I know of. You need to contact Zeiss directly.

Q: 9. Does this records metadata of the image if I use it in Leica M10?

A: You will get metadata just not from the lens. It is fully manual.

Q: 10. Will this fit on a Bessa R?

A: No, the Voigtlander Nokton 75mm f/1.5 Aspherical Lens will not fit on the original Voigtlander Bessa R. The Bessa R had the Leica Thread-Mount (LTM) and cannot use Leica M-mount lenses.