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Kerry L. Thalmann
12-Sep-2004, 15:53
I am considering adding a smaller 6x9 front standard to my ARCA-SWISS F-Line Classic camera. This is a smaller front standard that will allow me to directly use ARCA's smaller 110mm x 110mm lensboards.

I have two options: the standard F-Line 6x9 front format frame, or the F-Metric 6x9 front format frame. The F-Metric adds geared, self-locking front rise (vs. the standard non-geared rise on the F-Line Classic). In the past, I generally valued lighter weight over ease of use, but as I've gotten older I tend to put more emphasis on convenience even if it costs an ounce or two here or there. In other words, that self-locking geared front rise looks rather appealing to me.

So, here's my question. How does the rigidity of the self-locking F-Metric front standards compare to the conventional F-Line standards with locking knobs on both sides? One of the things I like about my ARCA-SWISS is the rock-solid rigidity in a camera that is still portable. Intuitively, it seems like the self-locking mechanism couldn't be as rigid as one with dual locking knobs, but I have always been impressed with the engineering abilities of the folks at ARCA-SWISS. If anyone could figure out a way to make a lightweight, self-locking geared rise that doesn't sacrifice rigidity, I'm confident it would be the folks at ARCA-SWISS. So, anybody out there who has used both F-Line Classic and F-Line Metric care to comment on the relative ease of use and rigidity of the two? All comments welcome.

Thanks, Kerry

Ed Burlew
12-Sep-2004, 18:59
Kerry, I have an F metric 8x10 and I hang a 155 Grandagon on the front with no problems of rigidity. I have done so for two years without any problem.

Ed

evan clarke
12-Sep-2004, 19:30
Hi Kerry, I have 3 Arcas, a 6x9 F compact, 4x5 F metrix/Orbix and an 8x10. The 6x9 front standard will decrease the amount of rise you will get. Arca makes a 171mm to 110 board adapter which fits in the camera in place of the standard board. I have these in both the larger cameras and all my lenses are mounted in 110 boards. The smaller boards pack better and I have no difficulty with large lenses like 360 Rodenstock ( or anything in a #3 Copal), 150 Super Symmar XL and the 360,500 720 Nikkor Tele set. I can see no loss of rigidity in the geared standards on my 4x5 and am actually considering an F metric 6x9 with Orbix, the geared movements are a real snap. The geared movements are as rigid or more than my Sinar P2 and a fraction of the weight and I actually think the geared rise 4x5 standard is lighter than the classic, it has only one knob...Evan Clarke

Frank Petronio
12-Sep-2004, 21:07
I'm wondering if you could retrofit an extra-large Misura style leather case with that beautiful round baseplate for backpacking. When you're in the woods, it's OK to treat yourself to a little luxury ;-)

Kerry L. Thalmann
12-Sep-2004, 23:48
Thanks for the responses. It sounds like rigidity is not an issue (as one would expect with an ARCA-SWISS).

Perhaps a little background info on my question would be in order. A little over a year and a half ago, I assembled a 4x10 camera using a Lotus 4x10 conversion kit and an older ARCA-SWISS A/B with a 6x9 front standard (older style). I was so impressed with the modular design of the older ARCA-SWISS camera, I bought a 4x5 F-Line Classic to replace my Linhof Technikardan TK45S (a perfectly wonderful camera, but not as modular as the ARCA-SWISS). My experience with these fabulous cameras, both old and new, led to an article on the evolution of the ARCA-SWISS cameras that was published earlier this year in View Camera Magazine.

In the mean time, I continued to amass a complete ARCA-SWISS system with a great many accessories. I have the 110mm adapter Evan mentioned above. I also have 110mm ARCA-SWISS lensboard for most of my lenses. I recently picked up a 4x5/6x9 tapered leather wide angle bellows. The two pieces I still need to add are a 6x9 front standard and a 50cm 4x5/6x9 tapered bellows.

Once I have those two items, I plan to adapt my 4x10 to work with the newer F-Line camera and ditch the older A/B model. This will give me a reasonably lightweight system that will handle both 4x5 and 4x10 with all my lenses from 55mm - 450mm. Basically an F-Line Field with a 4x10 conversion kit. The Lotus bellows are perfectly sized to work with the 6x9 front standard and will be easy to adapt to the newer camera. So, it all seems to fall into place.

The 6x9 front standard will decrease the amount of rise you will get.

Doesn't ARCA-SWISS make some kind of extender block that is designed to center the smaller front standards when using bigger rear standards? I thought they made one for raising up the 4x5 front standard when using it with an 8x10 rear standard. Could this extender block also be used to get a little more direct front rise when pairing a 6x9 front standard with a 4x5 rear? If not, there is always indirect front rise by tilting the rail up and using the base tilts to get the standards parallel (a piece of cake with the front and rear levels).

As I said, I've become a bit of a sucker for anything that makes my life easier in the field. That's where the standard F-Line vs. F-Metric question came from. As rigidity doesn't seem to be an issue, and weight difference appears negligible, I'll probably go with the geared front rise and the F-Metric 6x9 front format frame.

Thanks to all who responded.

Kerry

Emmanuel BIGLER
13-Sep-2004, 05:09
Kerry and Arca-Swiss users.



I recently upgraded from a 6x9 "classic" to a 6x9 "metric". No change in terms of rigidity whatsoever. To me the question of "metric" vs. non-metric is more a question of how you feel things manually than an issue about which option is better than the other. Arca Swiss dovetails are similar for a "classic" frame and for a "metric" frame. So you can even mix "metric" and "non metric" elements. Byron Ratzikis had raised the question for a 8"x10" camera.



Kerry, if you are not familiar with the 6x9 "metric" standard, you'll prebably be amazed since all the rising mechanism is contained inside a standard 6x9 "classic" frame. How the system can slide without locking if it is pushed only on one side ? There is well-know Murphy's law of drawers stating that a square drawer , or worse, a wide drawer, usually locks when you draw or push on one side only ; to be immune against this, a drawer should be much deeper that wide (a ratio of 1.4, like in photographic f-stop scales, being required for comfort);-);-)



The control knob on the "metric" frame is one side only, so at a fist glance the system should be prone to unwanted diagonal lock. On a classic standard, you gently draw or push with both hands. For the "metric" there is a small... "tric" that you'll discover by a careful examination of the mechanism of your future "metric" frame ;-);-) ("metric" owners please do not disclose the trick too early ;-);-)



More seriously : friction of A/S 'metric' movements is factory-adjusted are not designed to be adjusted by the owner. So some people actually prefer the non-geared classic slide which is very smooth. The geared metric rise has absolutely no play but some people could miss the feeling of smoothness of a "classic" manual rise. There is a critical trade-off betwen no-play and friction in a geared movement.



Another short story : if you are used to classic locking knobs, do not forger that the right-hand metric button operates in the other direction i.e. clockwise for "up" ; the classic right-hand locking knob is operated counter-clockwise to loosen when you start from the bottom ;-)



For front and rear rise I'm actually delighted by the "metric" option. For front and rear shift, the geared translation mechanism is superb and again housed in an incredibly narrow space. But like Byron I would be happy with the classical non-geared dovetail and clamp system for horizontal shifts.



As far as the front rise extender is concerned such an accessory has been on catalog for a long time for 5"x7" and 8"x10" F-line cameras. I principle nothing prevents the use of a similar accessory on a 6x9 standard. Same dovetail dimensions, same function carriers for all formats.

giancatarina
13-Sep-2004, 06:13
Doesn't ARCA-SWISS make some kind of extender block that is designed to center the smaller front standards when using bigger rear standards? i went to see the arca factory this summer, and i've ask the same question, they told me that something similar exist already for 4x5/8x10, but nothing for 6x9/4x5 yet, but they are going to make one probably this year !

Metric, or not metric ... if you are going to work in a dusty aera, maybe metric is not the best option if you want to use only one hand (second hand for a beer ...), then metric is the way to go

Thinking digital, i believe that the precision of the metric can be important, but both line share the same focus system anyway !

From what i've seen, the rigidity is as good as an arca camera, that is to say extremely good !

evan clarke
13-Sep-2004, 07:42
Hi All, One funny note about the Arca catalog: There is a 4x5 to 6x9 back adapter which allows the use of my 6x9 ground glass and roll film backs on my 4x5. It has been in the catalog for about 2 years or more and they have not yet made any to ship!!..Evan Clarke

Kerry L. Thalmann
13-Sep-2004, 10:26
For front and rear rise I'm actually delighted by the "metric" option. For front and rear shift, the geared translation mechanism is superb and again housed in an incredibly narrow space. But like Byron I would be happy with the classical non-geared dovetail and clamp system for horizontal shifts.

Emmanuel,

Thanks for the detailed information. What you state above is my intended solution (geared "metric" front rise, but with my existing dovetail clamp for horizontal shifts). I use front rise a lot more than shift. So, the self-locking geared rise will be a practical luxury (if there is such a thing) for me.

i went to see the arca factory this summer, and i've ask the same question, they told me that something similar exist already for 4x5/8x10, but nothing for 6x9/4x5 yet, but they are going to make one probably this year !

David,

This is good news and makes the switch to the smaller 6x9 front standard even better as the only compromise is the reduced direct front rise.

Kerry

Wisawa S.
15-Sep-2004, 16:12
Kerry,

Without "the extender block", you have 3cm. front direct rise/fall. You still have indirect rise/fall if necessary. So I think there is no need for the extender block.

Kerry L. Thalmann
19-Sep-2004, 14:30
Thanks again for all the responses. One more request... Could some kind ARCA-SWISS users please post the weight of their 6x9 front format frames for standard F-Line and F-Metric models? I have also thrown the Misura front format frame into the mix and requested the weight of that one in a different thread. I'm leaning towards the F-Metric 6x9 front format frame to add self-locking geared front rise to my F-Line Classic, but I'd like to have all the data (both pricing and weight) before I make my final decision).

Thanks, Kerry

Emmanuel BIGLER
20-Sep-2004, 03:37
Kerry. I'll look at the weight budget carefully.
The weight of a pair of F-line classic function carriers plus 2 classic 6x9 non-metric frames without ground glass or lens board
is about 1.6 kg : actually I had measured 1.7 kg including the standard 75-150 leather bellows.
So about 800 grams (1.8 pound) as a starting point for a classic function carrier plus a classic 6x9 format frame.
The difference between a classic frame and a metric frame is certainley less than 50 grams (~1-1/2 oz). I'll check this. The Orbix adds less than 100 grams (< 3.5 oz).
F-line function carriers are the heavy part of the stuff since they are designed to support a 8"x10" frame. In addition to light allows, they incorporate brass and steel parts for precision, smoothness and durability.

Kerry L. Thalmann
20-Sep-2004, 10:16
Emmanuel,

Thanks for the response. It's good to post the data here so others can have access to it in the future. I have a standard 4x5 F-Line Classic. I plan to continue to use the F-Line function carriers. What I'm really trying to determine is which 6x9 front format frame I wish to add to my existing 4x5 F-Line Classic. I'm really leaning to the Metric for the self-locking geared front rise, but am also considering the standard 6x9 Classic front format frame (least expensive, possibly lightest solution) and the Misura. I was under the mistaken impression that the Misura had geared front rise. I found out yesterday in another thread that it does not So, I'm leaning again to the Metric. I don't use lateral shift very much. So, I don't need the heavier Metric function carrier with geared shift - just the format frame to use with my existing F-Line function carrier. If you could post just the weight of a single 6x9 Classic format frame, and any others you have access to (Metric and Misura), I'd appreciate it.

Thanks, Kerry

Emmanuel BIGLER
21-Sep-2004, 05:24
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Kerry. As promised this is the detailed weight budget of a current A/S 6x9 metric with Orbix&reg; in front.



Weights in grams. exact conversion factors are : 1 ounce = 28.35 grams ; 1 pound = 16oz = 453.59 grams



Arca Swiss F-metric compact 6x9-6x9, 300 mm (12") folding rail, optional Orbix&reg; in front. Current model as of 2004.



Front "metric" format frame including 6x9 Orbix&reg; : 341
Rear "metric" format frame : 281
(Additional weight of the 6x9 Orbix&reg; : 60)
Standard 75-150 6x9-6x9 bellows, 110x110 frames : 95



6x9 ground glass & Fresnel lens : 150



300 mm (123) Folding Rail type II : 314
Connecting bracket to quick release clamp, 8.5 cm type II : 123



Functions carrier "metric" w. geared self-locking shift, front : 583
Functions carrier "metric" w. geared self-locking shift, rear : 603



Additional compendium rod holder : 27



Typical lens mounted on a 110 board ; 400-600 grams, heavier for telephotos of course.



Total weight of the 6x9 metric : about 2.5 kg / 5.5 pounds, slightly more than the misura w/o leather case but with baseplate. Clearly, metric functions carriers add bout 100 grams each w/respect to classic non-geared models. Metric frames are probably similar within a few grams to a classic non-geared frame. I had measured 1700 grams for both classic 6x9 standards, function carriers and bellows. Subtracting 100 grams for the bellows yields 800 grams for a non-metric functions carrier plus a non-metric frame. Classic non-geared functions carrier are therefore about 520 grams each. To be confirmed, I no longer have them handy ;-)



Other Comments.



The 6x9 Orbix mechanisms adds only 60 g to the weight and virtually nothing to the height of the frame. Truly amazing. The 4"x5" model is probably bigger, I do not know.



Misura bellows = same kind of molded leather bellows but more pleats, front size 110x110, and bigger rear size. (140 ?? 150 ?? less that 171, to be confirmed)



The rear metric functions carrier has an additional overhanging platform to short en the length between both standards.



The 8.5 cm connecting bracket represents 28% of the weight of the 30cm rail+bracket assembly. The simpilfied misura clamping dovetail saves weight.



The front misura standard is the same as a 6x9 non-metric with orbix so about 340 grams.

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Comments on the folding rail.



I just looked at my 30 cm (12") folding rail type II for a F-compact camera. I see no technical reason why the rail could not be totally free to be lifted up like in the misura. You need just to round-off one of the edges of a small rectangular part in the hinge. On the misura the rail cannot drop since it could hit the oval baseplate. My understanding is that A/S insisted that the rail should be fast to set-up, so that stopping the movement in the horizontal position allows you to easily align both halves before tightening them, even in total darkness ;-);-)

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guillaume p
21-Sep-2004, 11:09
Detailed weight budget of a misura
front format frame (classic-orbix) : 340 g
rear format frame : 330 g
belows : 200 g
groundglass + graflock frame : 370 g
front function carrier : 370 g
rear function carrier : 160 g
rail + base plate : 590 g
Total : 2360 g / 5.2 pounds
Leather case : 500 g

Kerry L. Thalmann
21-Sep-2004, 12:18
Emmanuel and Guillaume,

Thanks so much for posting the detailed weight budgets for the Metric and Misura. I'm quite swamped at work right now, but some time in the next couple days when I am home and have access to my camera and a scale I will post a detailed weight budget for my F-Line Classic. This will give me (and anyone else) all the information necessary to make a decision about how to configure my camera. Since the ARCA-SWISS cameras are totally modular and reconfigurable, perhaps ARCA-SWISS could include the weight of each item in a future version of their catalog (or perhaps on a web site someday).

Kerry

Frank Petronio
21-Sep-2004, 17:41
Maybe they could piggyback it on their American service provider's website for free? ;-)

Emmanuel BIGLER
22-Sep-2004, 04:05
Three obvious remarks.



1/ Leather is heavy ;-);-)



2/ 160 grams for the rear misura functions carrier instead of 370 (misura front, no gear) to 600 (metric, rear, full gears) gives sense to the idea of reducing weight with a simplified rear functions carrier ; the front misura functions carrier is also less heavy than a classic, without the gear system and one knob less.



3/ without ground glass the 4"x5" rear misura frame weights 330 grams for a total weight including GG of 600 grams. In 6x9 the similar equipment weights 430 grams. The reduction of weight vs. a F-4"x5" classic frame is certainly significant as well. Kerry will tell us precisely.

Emmanuel BIGLER
22-Sep-2004, 04:25
Oooops : 370+330 makes 700 grams for the rear format frame + GG of course ! to be compared to the 430 grams of the equivalent 6x9 parts.

We can make an estimate of the weight for the oval baseplate plus dovetail. A classic 30 cm folding rail type II weights 314 grams ; a proportional correction by 32/30 yields an estimate of 335 grams for the 32 cm misura rail. This leaves us with 590-335 = 255 grams for the oval plate plus simplified dovetail. So the misura without case nor clamping system would weight about 2100 grams including ground glass and graflock but without lens board.

Kerry L. Thalmann
22-Sep-2004, 12:35
I pulled out my scale and camera gear last night and weighed several of my ARCA-SWISS bits and pieces. Here's the results (my scale is only accurate to the nearest 5g, so consider these results +/-2.5g):

ARCA-SWISS 4x5 F-Line Classic:
Front Function Carrier - 455g
Rear Function Carrier - 455g
Front Format Frame - 550g
Rear Format Frame - 550g

30cm Optical Bench Telescopic* (current style) - 630g
30cm Optical Bench Telescopic* (older style) - 555g
40cm Monorail (current style) - 335g
40cm Monorail (older style) -310g

4x5 - 20cm Leather Wide Angle Bellows - 220g
4x5 - 38cm Standard Bellows - 275g
4x5 - 70cm Long Bellows - 550g
4x5/6x9 - 24cm Leather Wide Angle Bellows - 150g

4x5 Back with Ground Glass Panel (current style) - 500g
4x5 Rotating Back with Ground Glass Panel (older style) - 640g

171mm - 26mm Deep Recessed Lensboard (Copal No. 0) - 205g
171mm - Flat Lensboard (undrilled) - 180g
171mm - Flat Lensboard (Copal No. 3) - 150g
171mm - 110mm Lensboard Adapter - 170g
110mm - 7mm Recessed Lensboard (Copal No. 0) - 55g
110mm - Flat Lensboard (Copal No. 0) - 70g
110mm - Flat Lensboard (Copal No. 1) - 65g

Plastic Ground Glass Protector - 40g

The camera, as I generally carry it, it a bit of a hodge-podge mixture of older and newer ARCA-SWISS components. I prefer the older style, lower profile rails that clamp from the side. To me, they work every bit as good as the new (perhaps even better) and are a little lighter and less bulky. Unless weight is really an issue, I also use a rotating back off an older ARCA-SWISS (pre-1984) camera with my current model F-Line format frame and rear function carrier. Most of my lenses are mounted on 110mm lensboards, and I use the 171mm - 110m lensboard adapter with these lenses. The two exceptions, I use a 171mm deep recessed board with my 55mm lens and 171cm flat board with a 600mm lens in a Copal No. 3 shutter. I generally only carry these two lenses if I anticipate needing such extreme focal lengths

The total weight of what I currently carry = 3900g / 8.6 lb.
This total includes:
30cm Optical Bench Telescopic (older style) - 555g
4x5 F-Line Classic Front Function Carrier - 455g
4x5 F-Line Classic Rear Function Carier - 455g
4x5 F-Line Classic Front Format Frame - 550g
4x5 F-Line Classic Rear Format Frame - 550g
Rotating Ground Glass Back (older style) - 630g
4x5 - 20cm Leather Wide Angle Bellows - 220g
4x5 - 38cm Standard Bellows - 275g
171mm - 110mm Lensboard Adapter - 170g
Plastic Ground Glass Protector - 40g

If I want to save 140g, I can use the standard 4x5 back in place of the rotating back. I'm not sure what the 4x5/6x9 50cm bellows weighs, but I'd guess it's about the same as the standard 38cm 4x5 bellows (275) - anybody have one they can weigh? If I kept everything else the same and went with the 6x9 Metric (non-Orbix) front format frame, 4x5/6x9 24cm Leather Wide Angle Bellows and 50cm 4x5/6x9 Long Bellows, I'd save an additional 530g. Not exactly a huge amount of weight, but I'm leaning that way for the geared front rise, lower weight and less bulk.

Also, I have a 4x10 project camera that is currently based on an older ARCA-SWISS chassis that uses the older style A/B 6x9 front format frame (340g with built in axis tilt). This project camera was what lead me into the ARCA-SWISS system in the first place. Since the 4x10 has a bellows that tapers down to approximately 110mm at the front, it is also a good match for the smaller 6x9 Metric front format frame. That would let the 4x10 share the same chassis and front standard as the 4x5, further reducing weight and bulk when I want to carry both formats. And again, this was what lead to my original question about the various current 6x9 front format frames.

Kerry

Emmanuel BIGLER
24-Sep-2004, 11:37
Many Thanks Kerry. And (ahem) you said.. "metric" ;-);-) ?? My understanding was that in the US, only officials at the National Bureau of Standards used metric scales ;-);-)
And not kidding : we are now all set to virtually build our next "dreamed" Arca Swiss camera. Keep us informed about your 4"x20" project.

Ernest Purdum
24-Sep-2004, 14:35
Emmanuel, Maybe it has something to do with using the English language that has us tied to wondering how many links to a furlong or gills to a hogshead.



And to think that Thomas Jefferson advocated a decimal system before there was a metric system.



Does anybody know (or care) what king's foot was twelve inches long?



I have a slide caliper which almost measures current inches, but not quite. It dates from the period in which Munich measurements were not the same as Heidelberg dimensions.

Bart Langenaken
11-Nov-2004, 12:03
At Photokina 2004 Arca Swiss showed me a new type of front/rare frames of wich the weight was reduced by taking off metal out off the frames. You will win about 600 grams for a whole 4x5" camera. They also have a new type of lensboard; one with a bajonet. You have one lensplate with a round hole (with bajonet) and need only small round plates for the lenses.

Emmanuel BIGLER
11-Nov-2004, 15:01
Bart. Good news for Arca-philes. The frames you are referring to are the new 140mm standards identical to the rear misura standard. Downsizing from 171 to 140 is a major improvement in compactness already visible in the misura. So we can say now that those who insist on having full rear tilts will simply use the new 140 mm frames on their function supports with new smaller square bellows, 140 mm square front and rear instead of 171mm. The mixed 6x9-4"x5" approach in the new 140 mm F-line models is simply a front 6x9 and a rear 140mm 4"x5" frame connected by the misura leather bellows. New 140 mm frames will be (or already are) available in "metric" flavour as well.

The bayonet mount you are referring to, is based on a simple principle that I had seen implemented for quick-fit of threaded lens hoods. It is a conventional thread mount like the good old M42x1 for 35 mm lenses except that the diameter is bigger (can accommodate a #3 shutter) and with three complementary lobes ~60 degrees wide @ 120 degrees milled on both parts. You just push boths parts taking advantage of the milled lobes and you screw-in and lock by turning sligthly less than 60 degrees. Of course you can use conventional square boards if you wish, it is up to you : either the 140 mm threaded lens board with the bayonet mount, or conventional boards one for each lens.

Bart Langenaken
12-Nov-2004, 16:54
Does Arca also have recessed boards with bajonet? They also have lensboards 110x110 for a 6x9 frontstandard. Do they have also a bajonetsystem for the 110-lensboards?

Scott Rosenberg
12-Mar-2005, 15:34
Does anybody know (or care) what king's foot was twelve inches long?

The unit of measure 'foot' was not actually derived from a king's foot... that is a common misconception. Almost every culture has used the human foot as a unit of measurement. The natural foot (pes naturalis in Latin), an ancient unit based on the length of actual feet, is about 25 centimeters (9.8 inches). This unit was replaced in early civilizations of the Middle East by a longer foot, roughly 30 centimeters or the size of the modern unit, because this longer length was conveniently expressed in terms of other natural units:
1 foot = 3 hands = 4 palms = 12 inches (thumb widths) = 16 digits (finger widths)

This unit was used in both Greece and Rome; the Greek foot is estimated at 30.8 centimeters (12.1 inches) and the Roman foot at 29.6 centimeters (11.7 inches). In northern Europe, however, there was a competing unit known in Latin as the pes manualis or manual foot. This unit was equal to 2 shaftments, and it was measured "by hand," grasping a rod with both hands, thumbs extended and touching. The manual foot is estimated at 33.3 centimeters (13.1 inches).

In England, the Roman foot was replaced after the fall of Rome by the natural foot and the Saxon shaftment (16.5 centimeters). The modern foot (1/3 yard or about 30.5 centimeters) did not appear until after the Norman conquest of 1066. It may be an innovation of Henry I, who reigned from 1100 to 1135. Later in the 1100s a foot of modern length, the "foot of St. Paul's," was inscribed on the base of a column of St. Paul's Church in London, so that everyone could see the length of this new foot. From 1300, at least, to the present day there appears be little or no change in the length of the foot.

Late in the nineteenth century, after both Britain and the U.S. signed the Treaty of the Meter, the foot was officially defined in terms of the new metric standards. In the U.S., the Metric Act of 1866 defined the foot to equal exactly 1200/3937 meter, or about 30.48006096 centimeters. This unit, still used for geodetic surveying in the United States, is now called the survey foot. In 1959, the U.S. National Bureau of Standards redefined the foot to equal exactly 30.48 centimeters (about 0.999998 survey foot). This definition was also adopted in Britain by the Weights and Measures Act of 1963, so the foot of 30.48 centimeters is now called the international foot.