Thickness of film support

[Petzi]

General consensus seems to be with film manufacturers, that

a) 35mm film is coated on 0.12 or 0.13 mm film support
b) MF film (120, 220) is coated on 0.10 mm support
c) LF film is coated on 0.19 mm support

Now I can understand that the sheet film is somewhat thicker than the other film, but why is the MF film thinner than the 35mm?

Is the film thickness specified in some industry standard?

 

[Lopaka]

To put it the other way, 35mm support is thicker than 120 to engage the sprocket holes without tearing.

Bob

 

[avandesande]

35mm was conceived initially to be used in motion picture cameras, hence the sprocket holes and thickness for durability.

 

[Roger Hicks]

35mm was conceived initially to be used in motion picture cameras, hence the sprocket holes and thickness for durability.

And Ilford Delta 3200 is on the thicker, dyed 35mm base even in 120 because the market is too small to support separate coating runs on 120.

Cheers,

R.

 

[Photo Engineer]

I have just measured 3 different rolls of Kodak and Ilford 35mm film and I get 0.15mm or 5 mils plus a tad.

I measured 2 rolls of Kodak 120 and get the same values.

I measured 1 sheet of Kodak 4 x 5 and get 0.2mm or 7 mils plus a tad.

I measured the large 42" roll of uncoated estar and get 7 mils.

Hope this helps.

I used a combo metric/english micrometer.

PE

 

[Roger Hicks]

I have just measured 3 different rolls of Kodak and Ilford 35mm film and I get 0.15mm or 5 mils plus a tad.

I measured 2 rolls of Kodak 120 and get the same values.

I measured 1 sheet of Kodak 4 x 5 and get 0.2mm or 7 mils plus a tad.

I measured the large 42" roll of uncoated estar and get 7 mils.

Hope this helps.

I used a combo metric/english micrometer.

PE

Dear PE,

What are the coating thicknesses as compared with the base thickness? Could the anti-curl/anti-halation layers on 120 add significantly to the overall thickness? You are one only a dozen or so people I know who could answer these questions...

Cheers,

R.

 

[Photo Engineer]

The 'tad' mentioned above is the coating thickness. The thicknesses are 5 mil and 7 mil respectively for the supports I measured.

The coating thickness is in the micron level. If you look at published photomicrographs, you will see that the coated layer is just a tiny fraction of the thickness of the support.

If you wish, I can look up a photomicrograph in a textbook and scan and publish it here.

I erroniously reported a 2 mil support at one time, but that was specially made for NASA to reduce weight in space flights and to increase the footage of film that could be placed in a camera.

PE

 

[Roger Hicks]

The 'tad' mentioned above is the coating thickness. The thicknesses are 5 mil and 7 mil respectively for the supports I measured.

The coating thickness is in the micron level. If you look at published photomicrographs, you will see that the coated layer is just a tiny fraction of the thickness of the support.

If you wish, I can look up a photomicrograph in a textbook and scan and publish it here.

I erroniously reported a 2 mil support at one time, but that was specially made for NASA to reduce weight in space flights and to increase the footage of film that could be placed in a camera.

PE

Dear PE,

I'd seen photomicrographs -- thanks for the offer -- but they've always been of 35mm as far as I recall. What you say accords with what I thought I knew, but I always prefer to check with someone who doesn't just think they know, so thanks again.

Cheers,

R.

 

[Petzi]

What are the coating thicknesses as compared with the base thickness?

Dear R.,

you can find this information in some of the film data sheets. In Agfa data sheets I found this:

Negative film:
XPS 160: 18 μm
Optima 100: 16 μm
Optima 200: 18 μm
Optima 400: 19 μm

Slide film:
RSX II 50: 25 μm
RSX II 100: 25 μm
RSX II 200: 27 μm

B/W film:
APX 100: 7 μm
APX 400: 10 μm

 

[Roger Hicks]

Dear R.,

you can find this information in some of the film data sheets. In Agfa data sheets I found this:

Negative film:
XPS 160: 18 μm
Optima 100: 16 μm
Optima 200: 18 μm
Optima 400: 19 μm

Slide film:
RSX II 50: 25 μm
RSX II 100: 25 μm
RSX II 200: 27 μm

B/W film:
APX 100: 7 μm
APX 400: 10 μm

DUH! Very good -- I should have thought of that.

Thanks,

R.

 

[StoneNYC]

Also, 120 has backing paper which add to thickness so that's why some 120 is thinner to make room vs 35mm with no backing paper, but also the sprockets

 

[AgX]

Type 120 is not made thinner to give room for the paper. Rather type 135 has been made thicker due to stress on perforations during transport.

 

[Xmas]

Base thickness depends on base material and duty 35mm PET eg for dimensional stability can be thin enough for 72 exp per cassette

Cine had two sprocket standards camera for picture frame to frame registration projector for life.

5222 (Double-X) seems to be thicker than Trix currently.

 

[Xmas]

this thread was started in 07!

 

[StoneNYC]

this thread was started in 07!

Weird... Because I didn't search for this, maybe it was linked to me because of the discussion about the thickness of the 4x5 Double-X cine film I started (which is almost at the minimum order if 200 boxes yes!) sorry about that, lol

 

[frobozz]

Weird... Because I didn't search for this, maybe it was linked to me because of the discussion about the thickness of the 4x5 Double-X cine film I started (which is almost at the minimum order if 200 boxes yes!) sorry about that, lol

I confess, I was the one who linked to this, just because it had actual numbers for base thicknesses, and we were discussing that subject in one of the Double-X threads.

Duncan

 

[StoneNYC]

I confess, I was the one who linked to this, just because it had actual numbers for base thicknesses, and we were discussing that subject in one of the Double-X threads.

Duncan

Thanks haha, well at least we know the source! Haha there are so many Double-X related threads between APUG / LFF / and even FB I'm getting a little confused haha

 

[Sal Santamaura]

this thread was started in 07!

...sorry about that...

Why? There's no reason to apologize for adding to an existing (regardless of age) relevant thread rather than starting a new, redundant one. It keeps the database cleaner and easier to search. I encourage this optimal practice in all forums.

 

[StoneNYC]

Why? There's no reason to apologize for adding to an existing (regardless of age) relevant thread rather than starting a new, redundant one. It keeps the database cleaner and easier to search. I encourage this optimal practice in all forums.

Good point! Then I'm not sorry lol

 

[lxdude]

Why? There's no reason to apologize for adding to an existing (regardless of age) relevant thread rather than starting a new, redundant one. It keeps the database cleaner and easier to search. I encourage this optimal practice in all forums.

I agree.

 

[MattKing]

For this thread, where the title is clear and explanatory, I too agree.

If the important nugget of information is buried within a thread that appears to be about something entirely different, not so much.

 

[Mark_S]

I looked at the standards that the motion picture industry has for 35mm film - they have four different standards defining the dimensions of the film and the sprocket holes (there are different sprocket hole dimensions for different 35mm motion picture films) - although the standards are very studious about defining the dimensions and the conditions under which they are measured (temperature, relative humidity etc), none of the four standards define film thickness except in an informative annex (manufacturers are not required to follow anything in the informative annex - it just gives background info), in the infomative annexes for the standards there is a note which says:

"Film for positive use has a longitudinal pitch 0.2% longer than its companion negative. Shrinkage of the negative
during aging and processing prior to printing will generally not exceed 0.2%. Thus, the negative stock is expected to be
0.3% ± 0.1% shorter than the positive. This difference will minimize slippage between the two on the 12-in (305-mm)
circumference sprocket of the printer, assuming a film thickness of 0.0055 in to 0.0065 in (0.140 mm to 0.165 mm)."

So it seems that the range of 5-7 mils is what one should expect.

If you want all the gory details, read SMPTE 139, 237, 93 and 102 - and for fun 119 (70mm perforated film)

 

[Xmas]

Most still cameras will accept cine negative film sprocket holes for example 5222 (XX) but people say xpans have problems donno...

The cine colour neg camera film will tolerate c41 processing chemicals in spiral tanks but will upset mini lab machines as the rem jet material can destroy subsequent films processed until the debris is removed.

The PET base films can have much thinner bases so you can get 72 frames on a cassette this is ok if you deep tank process or have custom spirals some 135 film is on PET for dimensional stability this tends to light pipe...

Donno if these PET bases leave a pressure plate problem not detected problems myself.

120 and 220 film is normally the same thickness but normally the pressure plate is different to allow for the paper backing.

620 film is the same as 120 though the spools are different.
.

 

[StoneNYC]

Most still cameras will accept cine negative film sprocket holes for example 5222 (XX) but people say xpans have problems donno...

The cine colour neg camera film will tolerate c41 processing chemicals in spiral tanks but will upset mini lab machines as the rem jet material can destroy subsequent films processed until the debris is removed.

The PET base films can have much thinner bases so you can get 72 frames on a cassette this is ok if you deep tank process or have custom spirals some 135 film is on PET for dimensional stability this tends to light pipe...

Donno if these PET bases leave a pressure plate problem not detected problems myself.

120 and 220 film is normally the same thickness but normally the pressure plate is different to allow for the paper backing.

620 film is the same as 120 though the spools are different.
.

Not to detract from the normal thread, but you mentioned that the center films would tolerate C41 processing, but that's contradictory to what I understand, the sin of films are an ECN-2 process, which uses different chemistry them C41

 

[Xmas]

confirmed the cine colour neg is not C41 but it will be ok in C41chemicals with dip and dunk or spiral tank.

It is like 5222 'needs' D96 and trix D76...

Wet printing may be more difficult dependent on enlarger, scanning no problem

but don't try it with a mini lab unless you know the managers real well. Some machines can cope if the staff are trained.

It is nice film as the rem jet layer reduces burn relative to normal 135 colour

when you finish washing in spiral you need to sponge off remjet layer under bath faucet in good light

try a short end if you home process c41

If you can get short ends and don't need mini labs it can be real cheap...