The WillTravel design height of the camera bodies is based on the minimum Flange Focus Distance (FFD) for that particular focal length. FFD in this context is the distance from the back of the shutter and to the filmplane/Groundglass. And then adapting for longer FFDs by extending the Frontcap length. Different lens design / brands in the same focal will have slight differences in FFD, thus check the table below to get the Frontcap and funnel which matches your lens.

The design criteria’s is to be able get the camera to infinity focus i.e. minimum extension and at the same time be able to focus nearer by turning the frontcap further out, whilst have a sufficiently engagement on the threads to ensure stability and light sealing.

8 mm thread pitch is selected for focal lengths of 90mm and less. Focal lengths from 100mm has a thread pitch of 12mm. This allows for a focus change from infinity to quite closely (1-2m) with one turn of the frontcap.

The internal funnel is there to prevent the frontcap with your valuable lens from suddenly disengagement on the threads and thus the risks of falling on to the ground and be damaged.

WillTravel - Design Data

Focal lengthMin FFDMax FFDDesign FFDThread Pitch
4759,159,1578
5869,369,3618
6563,573,4618
7282,282,2798
7581,385,1798
9090102,8888
10000012
120135,3135,313012
12113213213012
12700012
135127,7133,812612
150137148,313612
FFD = Flange Focal Distance
(all data in millimeter)0= no data (yet)
Identified max and min FFD for the lenes below, with design decision FFD for each focal length.

Lensdata

Below are what I currently have found of lens data, particularly FFD data. Should your lens be missing from the table, send me a email (morten@kolve.org) and let’s research. Or even better should you have data that could be added.

Maximum calculated Frontcap length to be able to reach infinity, i.e minimum extended. A few millimeter shorter might be ok, key is to still have good thread engagement when you are your maximum close up focus. Note this is NOT a macro camera design 🙄.

Minimum calculated Funnel length to be able to turn Frontcap one full turn from infinity. Longer might be possible, but you need to test for mechanical vignetting. (With a film exposure, groundglass peeping is not sufficient.I have learnt this in real life. 😬)

Focal lenghtNameMax formatFFDShutterMax FrontcapMin FunnelComment
47Will Travel design decisionN/A57N/AN/AN/ABody not published.
47Super angulon xl 47/5.64x559,1#022,130,1
58Will Travel design decisionN/A61N/AN/AN/AN/A
58Super angulon xl 58/5.64x569,3#028,336,3Use 65mm body.
65Will Travel design decisionN/A61N/AN/AN/AN/A
65Angulon 65/6.84x563,5#0022,530,5
65Grandagon n 65/4.54x570#02937
65Super angulon 65/84x570,5#029,537,5
65Nikkor sw65/44x570,8#029,837,8
65Super angulon 65/5.64x572,5#031,539,5
65Fujinon swd 65/5.64x573,4#032,440,4
72Will Travel design decisionN/A79N/AN/AN/AShare 75mm body
72Super angulon xl 72/5.65x782,2#023,231,2Use 75mm body
75Will Travel design decisionN/A79N/AN/AN/AN/A
75Nikkor sw 75/4.54x581,3#022,330,3
75Grandagon n 75/4.54x582#02331
75Fujinon swd 75/5.64x585,1#026,134,1
90Will Travel design decisionN/A88N/AN/AN/AN/A
90Angulon 90/6.84x590#02230Tests ok with Frontcap 23, Funnel 35mm
90Grandagon n 90 6.85x794#02634Same as Caltar II-N 90mm f6.8
90Nikkor SW 90 85x797#02937
90Nikkor SW 90 4.55x797,4#029,437,4
90Grandagon n 90 4.55x798#13038
90Super Angulon 90/85x798,8#030,838,8
90Fujinon sw 90 85x799,2#031,239,2
90Lf topcor 90 5.65x7101,3#033,341,3
90Fujinon swd90 5.65x7102,5#034,542,5
90Super Angulon 90/5.65x7102,7#034,742,7
90Super angulon xl 90/5.65x7102,8#034,842,8
100Will Travel design decisionN/A0N/AN/AN/ABody not published.
100….4x5000Not published.
120Will Travel design decisionN/A130N/AN/AN/ANot published. Will be shared 120/121 body
120Super symmar HM 120/5.65x7135,3#035,347,3Not published. Will be shared 120/121 body
121Will Travel design decisionN/A130N/AN/AN/ANot published. Will be shared 120/121 body
121Super Angulon 121/88x10132#03244Not published. Will be shared 120/121 body
127Will Travel design decisionN/A125N/AN/AN/ABody not published.
127Pola 110 lenses4x5127#000Not published.
135Will Travel design decisionN/A126N/AN/AN/AN/A
135Fujinon w 135/5.65x7127,7#031,743,7
135Apo symmar 135/5.64x5128,2#032,244,2
135Apo sironar n 135/5.64x5130#03446
135Apo sironar s 135/5.64x5132#03648
135Cm fujinon w 135/5.65x7132,4#036,448,4
135Nikkor w 135/5.64x5133,8#037,849,8
150Will Travel design decisionN/A136N/AN/AN/AN/A
150Geronar4x5137#03143
150Apo sironar w 150/5,65x7141#13547
150Apo sironar n 150/5,65x7142#03648
150Xenar 150/5,64x5142,6#036,648,6
150Fujinar-w 150 / 6.34x5142,8#036,848,8Cap :35 Funnel : 50mm
150Fujinon w 150/5,65x7143#03749
150Apo symmar 150 5,65x7144,2#038,250,2
150Lf topcor 150/5,65x7144,2#038,250,2
150Cm Fujinon w150/5,65x7144,3#038,350,3
150Nikkor w 150/5,65x7146,8#040,852,8
150Apo sironar s 150/5,65x7147#04153
150G-claron 150/94x5148,3#042,354,3
150Nikkor sw 150/85x7165,9#159,971,9
150Super symmar hm150 5,65x7168,3#162,374,3

Sources:

http://homepages.tig.com.au/~cbird/nikkor/sw.html#SW90

http://www.kenko-pi.co.jp/horseman/e/lens_list.html