Film thickness

Does anyone know the actual film thickness(base + emulsion) of slide

film like Fuji Velvia or negative film like Fuji Reala. I've read

posts concerning back focus issues of Konica vs. Leica that say it's

about 0.20mm or 0.21mm for Pan F film but that seems a little high. I

always assumed between 0.135mm - 0.16mm film thickness. Can anyone

clarify? My concern is with slide film.

<p>It's in the data sheets, but it is basically <i>irrelevant</i> to the back focus isse. The emulsion is on the front of the film, on the side that faces the lens, on the side that rests on the film guide rails. The only (second order) way it can matter is if the outer guide rails are proud of the inner one by much more than the film thickness, in which case it will curl between the rails.</p>

Data supplied by Fuji or Kodak only state film base thickness. Does anyone know how much the emulsion thickness is for film like Velvia?

A sprung pressure plate should account for any differences in the thickness of the film, and as John points out, the emulsion is on the front surface. So even if the film was one foot thick, the emulsion is still on the front, and the distance from the lens would be the same as if the film was 0.1 inches thick.

You can measure these tiny thickneses with a micrometer. Go to a metal shop with a few slides and ask to use one. I have one in my toolset, but no Velvia handy, sorry, no Grey Poupon ...

This actually is relevant if you are measuring the film emulsion position from the front

surface of the pressure plate to the front (emulsion) surface of the film. This is how you

have to do it if the film is thinner than the distance between the inner and outer rails.

Veliva 50 is approx. .007" thick converted that would be .1778mm approx. My micrometer only measures to the 1/1000th but this was about as dead on .007 as it gets.

 

Have fun

PanF+ thickness: 5.5 mil

In most 35mm cameras, the pressure plate DOES NOT press directly on the film, instead, the pressure plate presses on a pair of channel

guides, one on top of the film plane, one at the bottom. The height of

the channel bar is about 200 micron<P>

 

A typical film such as PanF+ has a film thickness of 5.5mil =138 micron, leaving a leaway of about 60 micron for the film to wriggle

around, the thinner the film, the more wriggle room ( hence less

precision of positioning of film plane )<P>

 

Contax RTS III has a vacuum sucker which reduce the wriggle room<P>

 

Minox IIIs, B, TLX etc use different mechanisim to achieve the same precision. Minox ultraminiature camera has a dynamic pressure plate, it presses directly on the film, hence achieved precision of film plane.

When advancing the film to next frame, the dynamic film plane is

lifted away from the film momentarily to allow the film to move freely. When clocking film shutter, the pressure plate again presses

tighly and directly on the film.

"PanF+ thickness: 5.5 mil"

 

amazing how they would wind that onto a canister...

Eric, what is your problem ? <P>

 

mil1 ( P ) Pronunciation Key (ml)

n.

A unit of length equal to one thousandth (10-3) of an inch (0.0254 millimeter), used, for example, to specify the diameter of wire or the thickness of materials sold in sheets.

don't get snotty with me young man. 5.5mil? that's a problem. mil is short slang for the spoken word millimeter, which 5.5 is almost 0.220" which would be hard to wind onto a canister.

You are dead wrong !

 

Is is customary to write 1 millimeter as 1 mm

and 1/1000 of an inch as 1 mil.

 

mil IS 1/1000 of an inch<P>

 

See www.dictionary.com:

 

http://dictionary.reference.com/search?q=mil

 

<P>"

mil1 ( P ) Pronunciation Key (ml)<P>

n.

A unit of length equal to one thousandth (10-3) of an inch (0.0254 millimeter), used, for example, to specify the diameter of wire or the thickness of materials sold in sheets. <P>

A milliliter; one cubic centimeter.

A unit of angular measurement used in artillery and equal to 1/6400 of a complete revolution. <P>

It is a common English usage in photography that film thickness is often expressed in mil (0.001 inch)<P>

 

 

Example:<P>

<a href="http://www.fotoinfo.com/info/technicalinfo/paperfilmspec.html">Kodak Paper and film spec </a><P>

 

"Film Thickness <P>

35mm and 70mm Still Camera Films<P>

KODAK T-MAX 100, T-MAX 400, and T-MAX P3200 films are 5 mil (.005 in)<P>

KODAK PLUS-X and KODAK TRI-X Films are 3.6mil (.0036 in)<P>"

 

 

 

Show me one example that film thicknes is expressed in "mil as millimeter" like you did. Can you ??

you sure get excited don't you?

 

"You are dead wrong ! Is is customary to write 1 millimeter as 1 mm and 1/1000 of an inch as 1 mil. mil IS 1/1000 of an inch"

 

no, just like this whole thread has expressed before you, it is not customary. have you even googled your obscure abrevation? you could have saved yourself a little excitement Martin if your last post was posted first...

See what Eastman Kodak said><P>

 

http://www.kodak.com/global/en/professional/support/techPubs/p255/p255.jhtml<P>

 

<a href="http://www.kodak.com/global/en/professional/support/techPubs/p255/p255.jhtml">KODAK PROFESSIONAL Technical Pan Film 2415 </a><P>

 

 

KODAK PROFESSIONAL Technical Pan Film 2415 Size mm x ft Film<P>

Code Base Sp No. Letter Code CAT No. <P>

35 x 150 2415 4-mil<P>

(0.10 mm)<P>

ESTAR-AH 442 TP 129 9916 <P>

 

 

 

Size Film

Code Base Letter Code CAT No. 135-36 2415 4-mil (0.10 mm)<P>

ESTAR-AH TP 129 7563 <P>

It is not obscure, it is STANDARD technical specification in all

Kodak, Ilford film !

ERIC; "mil" has been used in engineering in the USA for over a century.<b> In Electrical Engineering; the wire gauges are LEGALLY DEFINED by a system based on the mil.</b> 36AWG is 5.000 mils; 0000 wire is 460 mils in diameter EXACTLY. ALL other American wire gauges are are LEGALLY defined by these two numbers. Each next guage varies as the 39th root of 92. <BR><BR>When you have a house built in the USA; it legally usually follows the Electical codes. "mil" has been around as a legally defined term in Engineering for over a century; and is legally mentioned in laws; and codes. Crossectional area in wires is in circular mils; this goes back to Thomas Edison and the electric motor.<BR><BR> Electrical engineering textbooks from 1900 go into these basic concepts of the mil; wire guages etc. Because one has not heard of a term is no reason to debunk a legally defined term; well used; that is over a century old.

"mil" was used in the Professional Engineering Exam I took in California; in the 8 hour test; on one of the questions. Maybe if this bothers folks you can protest to Arnold; Barbara; and Diane :)

We were talking about FILM thickness not wire gauge !<P>

 

Show me ONE Kodak/ Ilford, Fuji doccumet using "wire gauge" to measure

film. Please ?? <P>

 

You simply cannot <p>

Thanks Kelly, informative with manners...

 

Martin, wire and sheet is both measured in guage, figure it out.

Kodak some times expressed film thickness in mil (0.001 inch) some times they went metric, and use mm (millimeter)<P>

 

German film often expressed in PET, for example Agfa Copex Rapid

is PET 06, which is 60 micron<P> Converted to Kodak/Ilford usage

the thickness is 2.4 mil.<P>

 

Why "mil" is associaed with 1/1000 of an inch.<P>

 

 

My interpretation <P> "mil" probably stood for "milli"<P>

 

 

 

A "milli" of what ?<P>

 

In metric system, one milli of a meter is of course one mm (not mil )( Eric still need to provide ONE proof, use Google if you like)<P>

 

In English system one mil = milli of an inch<P>

proof of what? where did i say that film isn't measured like you say? where have i said you are wrong? if you expect the common person to know what is, or relate to, "5.5 mil1" then carry on i guess.