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Paul Kinzer
9-Dec-2017, 12:55
I'm making plans to build some 14x17 holders, and I'd like them to meet ANSI standards, but when I look at this (http://home.earthlink.net/~eahoo/page8/filmhold.html) page, it says the 'exposure height' is 17.062 inches. I have some 14x17 x-ray film, and it measures 16.906 inches long. How's that work?

Is x-ray film different from standard film (I didn't think it was); or is this page incorrect; or are the ends of the film not captured by the holder; or am I missing something it the definition of 'exposure height'?

Randy Moe
9-Dec-2017, 13:19
Film area coverage usage varies somewhat. I have 14 X 17 plastic medical XRay holders and they turn 17" into 16". I lose 7/8"

X-Ray film is 14x17" minus maybe 1/8" in each dimension. All LF film is undersized to slide into holders.

They are no ULF holder standards. The standards only go to 8X10. I was looking at 1951 ASA standards last night as published in 1970 National Camera Photo Technology Data Book.

What is your data source?

sanking
9-Dec-2017, 14:34
.....

They are no ULF holder standards. The standards only go to 8X10. I was looking at 1951 ASA standards last night as published in 1970 National Camera Photo Technology Data Book.




There were ANSI standards for 11X14" and 14X17" film holders, but not for other formats like 7X17, 8X20, 12X20 and 20X24.

However, not all 14X17" holders were built to ANSI standard.

Sandy

Randy Moe
9-Dec-2017, 15:11
Sandy is the last word on this.

Found this online. http://altphotolist.org/lists/alt-photo-process/2002/may02/msg00528.html

Every time I post this next link, somebody, not Sandy, tells me it's all wrong. http://home.earthlink.net/~eahoo/page8/filmhold.html

I buy my holders and would not be able to make one to any standard.

I do know by purchase of new holders, ymmv.

Paul Kinzer
9-Dec-2017, 15:48
Thanks for the responses!

Randy: My source for the data is at the link in my OP, which claims to get them directly from ANSI; there's even a link to ANSI there. My understanding, from reading somewhere here or elsewhere, is that x-ray may be the reason there is an ANSI standard for 14x17, since it is a common size for chest x-rays. But who knows if that's actually true?

Sandy: I guess my question is: how can holders be built to the ANSI standard if that standard calls for an opening that is longer than the actual film? I've got a sheet of Kodak 14x17 x-ray film in front of me right now, and it's short of 17 inches long by a hair less than a sixteenth of an inch***, but it is shorter. Would it not tend to fall out of a holder with an opening that is longer than 17 inches?

I just looked at that page again, and it seems that this 'exposure height' measurement gives too-long dimensions in each film format: 2x3, 3x4, 4x5, 5x7, 8x10, 11x14; all show a length that is longer than the nominal long dimension of the film format: 3 is 3.338; 4 is 4.228; 5 is 5.002; 7 is 7.010; 10 is 10.026; 14 is 14.086; and 17 is 17.026. The long dimension of my Riteway 4x5 holders is 4.75; and my Ansco 5x7s are 6.625. So what does this mean? What does this measurement actually measure?

*** Does this mean that x-ray film comes in significantly different sizes? If Randy's measures 1/8th less in each dimension, and mine is less than 1/16th, I'd better give myself some wiggle room.

Paul Kinzer
9-Dec-2017, 15:51
Randy: we just cross-posted. The link you gave as the one everyone says is 'all wrong' is the one I referred to in my first post. I'll read your other one with care. Thanks again to both of you.

Paul Kinzer
9-Dec-2017, 16:09
The crucial information from the link Randy gave above is:

'I think this is for the 14X17 holder.

Height =19.563" minimum
Width = 15.938"-16.000"
Thickness =0.686" maximum
Depth to septum (T) = 0.320" - 0.016"
The far edge of the raised ledge that fits into the slot on the camera back
is 19.288" maximum from the end of the holder where one loads the film. It
should be 0.061" +/- 0.015" high.
The bottom flap (F) is 1.043" maximum.'

This seems like enough information to go on for the making of my holders, and then my camera. I can use the sheet of film for any other info I need. As for the thickness of the holder, I'm going with something above the maximum given here. 0.686 inches would only give me room for a septum 0.046 inches thick, or less than a sixteenth of an inch.

But I'd sure be grateful for any feedback from folks who've got or made holders of their own.

Randy Moe
9-Dec-2017, 17:49
I unboxed 1 of my 3-14x17 holders. NOS. Tomorrow I will waste one sheet of 14x17 2X, No big deal. Glad to do it.

What's missing on those ANSI specs is the rebate areas on the width and the length. Rebate area is what holds the film in. And barely the bigger everything gets.

My measurement tools are packed somewhere...else. I did some rough tape measurements. The side rebates will be greater than 1/4" each. The usable image dimensions on these are 13-9/16" wide and 16-1/4". I suggest you keep these large rebates to hold your film better. Film is floppy at this size. It will hang down when shooting down. It will warp when shot vertically. I suggest you shoot at the Moon for film flatness. (small joke) The holder main body is about 5/8" thick.

The film I have is Kodak made Carestream, cut in Mexico, double sided (2X) CSG with the same blue tint all X-Ray seems to have, to prevent eyestrain.

I'll measure it tomorrow when I can get to it. I guessed at the minus 1/8" dimension.

If you want more pics, just ask.

https://farm5.staticflickr.com/4566/38946501271_80e56224c5.jpg (https://flic.kr/p/22kyZXe)IMG-0547 (https://flic.kr/p/22kyZXe) by moe.randy (https://www.flickr.com/photos/tincancollege/), on Flickr

https://farm5.staticflickr.com/4595/38230473524_a8cf1081ac.jpg (https://flic.kr/p/21fiaRf)IMG-0549 (https://flic.kr/p/21fiaRf) by moe.randy (https://www.flickr.com/photos/tincancollege/), on Flickr

Paul Kinzer
9-Dec-2017, 20:50
Thanks, Randy, this is a great help! More pictures, at least for now, aren't needed. I am curious to know if your film size is close to mine.

I'd love to buy my holders, but I just cannot justify the cost. My rough estimates so far tell me that I can buy the materials to make three for less than what it would cost to buy one; far less, depending on the price I go by ($585!?). And if I make three to the same specs, and then build a camera around them, I won't really need to be too concerned about exactly matching any standard other than the actual film size.

Randy Moe
10-Dec-2017, 17:51
Hi Paul, I had to wait for sunset. My darkroom is not ready.

The film IS minus 1/16" both ways from 14x17"


I am sure we all eagerly await your creations! Sorry watching 'The Crown'.

https://farm5.staticflickr.com/4685/25100956578_49ee78ebf8_z.jpg (https://flic.kr/p/Ef5XTq)IMG-0555 (https://flic.kr/p/Ef5XTq) by moe.randy (https://www.flickr.com/photos/tincancollege/), on Flickr https://farm5.staticflickr.com/4647/25100956478_087a35ab14_z.jpg (https://flic.kr/p/Ef5XRG)IMG-0556 (https://flic.kr/p/Ef5XRG) by moe.randy (https://www.flickr.com/photos/tincancollege/), on Flickr
These holders have 1/8" of room in both dimensions for film. The film could be exactly 14x17 and fit.

Paul Kinzer
10-Dec-2017, 21:48
Thanks, Randy!

I just sold a couple of cameras I refurbished on eBay, for more than I thought they might go for. I'm seriously thinking about getting a mini-milling machine. If I do, options for the camera build open up, though the time to build it does, too, since I have zero experience with mills, and not a whole lot of knowledge. I need to wait until I know the buyers are happy before I can spend the funds, so it will be a couple of weeks before I buy the wood for the holders (or the mini-mill). But I can mess around with sketching out ideas.

Randy Moe
11-Dec-2017, 02:18
Glad to help Paul.

I hope you document your project here.

Consider looking at a Router Forum and CNC machine kits. They is a lot of DIY innovation going on. I have a tiny mill/lathe that is not very good at what we need. Too small.

Paul Kinzer
11-Dec-2017, 20:42
Yeah, the CNC machines I might be able to afford would be too small, just like computer-guided telescopes for my astronomy habit are too small for my liking. But I just found one of these (https://www.harborfreight.com/two-speed-variable-bench-mill-drill-machine-44991.html) on Craigslist, bought by the seller to do one job, and now better than new since it's already been set up and put into good, usable shape (I've read they take a lot of tweaking right out of the box). And it's half the price of new, if you include what shipping would cost (though I do have to drive most of the way across Wisconsin to pick it up). The thing weighs 126 pounds, so shipping would be mighty spendy. I know I'll need to spend some more for the 'tooling' needed to use it, but it comes with some.

I do plan to document the build here (but it will be slow-going!) Folks here have been very generous with answering my questions, and with sharing a lot of deep knowledge. I'd like to add what I can; not deep, but helpful for folks who might want to try to learn from what I do. Probably mostly from my mistakes. :rolleyes:

Jim Fitzgerald
11-Dec-2017, 20:52
Paul, I have a mini mill. Most of what I read pertained to metal working. I've used my standard pouter bits in it and it works great for milling wood. It is a good investment and not hard to learn at all.

B.S.Kumar
11-Dec-2017, 21:41
I've used my standard pouter bits in it

Careful, now. :)

Paul Kinzer
12-Dec-2017, 17:44
Paul, I have a mini mill. Most of what I read pertained to metal working. I've used my standard pouter bits in it and it works great for milling wood. It is a good investment and not hard to learn at all.

I hadn't thought about using it for wood. That's good to know!

Jim Fitzgerald
12-Dec-2017, 17:49
BTW, I'm always careful.

Randy Moe
13-Dec-2017, 10:16
Are you watching Keith Canham on FB?

Let's see if this embed works. Deleted..

Nope! but look up and follow K. B. Canham on FB and watch how he makes his very nice cameras.

Paul Kinzer
13-Dec-2017, 11:42
Are you watching Keith Canham on FB?

Let's see if this embed works. Deleted..

Nope! but look up and follow K. B. Canham on FB and watch how he makes his very nice cameras.

Cool; I'll check it out!

GregDavis
13-Jan-2018, 23:17
Hi Everyone
I tried to buy the ANSI standard for film holders from official source but they would not provide it to me, as it has been withdrawn. I then sourced it from a less official Asian source, but still had to pay for it!

So now for the good of the photographic community, attached are the 4 most relevant pages of the ANSI IT3-108-1998 standard. The other pages are front cover, index, introduction, forward which are not technical.

I hope it is useful for you all.

173684173685173686173687

Jim Jones
14-Jan-2018, 08:33
. . . Every time I post this next link, somebody, not Sandy, tells me it's all wrong. http://home.earthlink.net/~eahoo/page8/filmhold.html. . . .


Randy, I'm the guilty party in at least some of these instances. It's not all wrong; there are only a few obvious errors. It is also less complete than the fairly up-to-date information that Greg Davis posted above. Greg's information is identical with the same specification I got directly from ANSI a few years ago, and with minor exceptions from the 1951 specifications in The Camera Repairman's Handbook. The older specification differed by including the 1/4" additions to 2x3 and 3x4 film sizes. The 1998 version adds the "J" dimension for the thickness of the septum in only the 11x14 and 14x17 holders, film sizes that the 1951 version did not cover.

Here is a reply to an earlier posting of Randy's link:
It should be noted that some of the information in this often cited illustration may be questionable. The depth to film surface distance (the "T" distance) as shown in my 1951 copy of the ASA standards is to the back, not the front, of the film. The Exposure Height measurement given is apparently the ASA D2, not the appropriate D3, measurement. The Exposure Width measurement is the E1 maximum, not the appropriate E3 measurement. The Retaining Tab Location is a maximum; the minimum is .010" less. The Length dimension is a minimum: ASA specified no maximum. The Width is a maximum: the minimum is about .031" less. The Distance to Exposure Field is a maximum: the minimum is .020 less for up through 5x7 holders and .030 less for 8x10 holders. I don't have ASA information on holders larger than 8x10. Dimensions in newer versions of the ASA or ANSI standards may differ.

At least the provider of the information Randy cited tried to be of service without violating copyright laws. Now that we are on the path to assembling comprehensive and accurate information, we should lay that citation to rest. This will be an ongoing process, and eventually should encompass the variations with which different photo equipment makers have plagued us for so long.

Paul Kinzer
14-Jan-2018, 14:38
At least the provider of the information Randy cited tried to be of service without violating copyright laws. Now that we are on the path to assembling comprehensive and accurate information, we should lay that citation to rest. This will be an ongoing process, and eventually should encompass the variations with which different photo equipment makers have plagued us for so long.

I really appreciate all the information that this thread has provided. The internet is full of answers, but this was one of those times when one of the most referenced sources of information (and not just by Randy!) seemed incorrect. That it is only partially incorrect made me, an inexperienced newcomer to all this, suspect that it was me who was wrong.

Since I'm actually going to use this information to make tangible things that I'll need to cut out of real wood and other stuff*, I'm going to print out the pages that GregDavis provided (thanks very much for that!). I tend to lose things that float around in my laptops, or my laptops do. People say that things online last forever, but I sure have not found that to be true. If there was some kind of average lifespan, that would be great, but too often I've gone looking for something fairly recent, only to get a 404 message. It might be a while (months to a year) before I get to the cutting. I don't want to lose this!

*I did get the mini mill I mentioned up-thread, and needed to completely rearrange my workshop in order to find a good place for it. The only times I was able to get out there coincided with sub-zero temperatures and strong winds. My workshop is insulated and heated, but not very well, so the work has been pretty slow and not very pleasant -- and long overdue! It's not quite done yet, either, so it will be while before I do some actual building on the camera. I was also right about buying tooling for the mill. I've no experience with machining, but now have most of the needed tools, several books, and a bunch of videos to get me going. The camera project has actually fallen far back in the queue of Stuff to Do. But I see that as a good thing. This is all fascinating and fun!

neilt3
14-Jan-2018, 18:30
Hi Everyone
I tried to buy the ANSI standard for film holders from official source but they would not provide it to me, as it has been withdrawn. I then sourced it from a less official Asian source, but still had to pay for it!

So now for the good of the photographic community, attached are the 4 most relevant pages of the ANSI IT3-108-1998 standard. The other pages are front cover, index, introduction, forward which are not technical.

I hope it is useful for you all.

173684173685173686173687


Very helpfull of you to post this .
I'm about to make a couple of cameras or adapt one other to use a larger format that was intended , and having this information to make a ground glass holder makes it easier to stick with standard gear like DDS if I can obtain some ( at the right price ) .

animaux
13-Apr-2018, 11:23
I’ve only just found this after getting it from somewhere else. I tried to do a modern representation of the data (https://temp.animaux.de/filmholders.html).

Paul Kinzer
14-Apr-2018, 21:53
Excellent! Another source to work with. This whole thread will be a great place for folks to come and find what they need for DIY.

I've gotten stalled on my actual camera build. It was only last week that I finally got my mini-mill tweaked to the point where I feel confident in its stability and tramming. That's been a fun project in itself, but so far, the only milling I've done is of parts for the mill. The time and money I've spent on measuring devices, tooling, practicing, and such has left me much more knowledgeable, but bereft of funds for the materials I need to actually build the camera. I need to regroup, buy some items to fix and sell (my source of income for my hobbies), and then continue.

I have gotten some stuff for the camera, including two lenses: a 19-inch Apo Artar and a 760mm Apo Ronar CL. I know that buying the lenses before having the camera might seem like a backwards thing to do, but I keep my eye out for deals, and found these two too good to pass up. $45 for the Artar, and $200 for the Ronar, which also came with a 240mm companion, both mounted on the same process camera board. I plan to sell the 240mm to recoup some of the cost of the 760. All the lenses came cheap because each was quite dirty. The Artar cleaned up nicely, but I have not messed with the others yet. None are in shutters, and I know I can probably do without, but I have some ideas.

By the way, though this is quite off-topic, since I brought up the Ronars, can anyone explain some writing on the aperture scales on the board? On the scale for the 240, it says 'Apo Ronar CL 240-800', and on the other scale it says, 'Apo Ronar CL 760-1200'. What do the 800 and 1200 signify?

animaux
16-Apr-2018, 23:43
BTW, what Mr. Hoover calls »Exposure Width« is the opening of the holder with an open darkslide. That is slightly larger than the film itself.

Nodda Duma
26-May-2018, 09:10
Tagging this thread for future reference (I'm working on plate holders).

-Jason

Renze
17-Oct-2018, 07:26
I am very confused about the lenghts of the film holder and the position of the retaining tab. The length (A) is 497mm and the position of the retaining tab is 490mm. So that leaves 7mm for the rest of the filmholder? Around 475mm seems more appropriate to me for the location of the retaining tab. Can anyone explain to me what I am missing?

animaux
17-Oct-2018, 23:27
I am very confused about the lenghts of the film holder and the position of the retaining tab. The length (A) is 497mm and the position of the retaining tab is 490mm. So that leaves 7mm for the rest of the filmholder? Around 475mm seems more appropriate to me for the location of the retaining tab. Can anyone explain to me what I am missing?

This is simply because A is defined as A min, e. g. minimum length for A. In practise you could make your holder as long as you want to.

For reference: http://lf.animaux.de/filmholders