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I am using a D5200 and want to make an attachment to support the lens at a distance away from the camera body. (There will be no lens mounted to the camera. Then there will be a gap. Then the lens.)

Because the lens support will be off-camera, and all components have to be aligned along the optical axis, the vertical height of the center of the center from the base of the camera is important. I am not able to find any reference/documentation online pertaining to this.

Any help, suggestions, or references for building this support, or finding the vertical height of the center of the sensor from the base of the body, would be appreciated.

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  • I don't quite get this. Why is the height from the base of the body relevant? It's centered in the lens. – Please Read Profile Jul 12 '18 at 11:28
  • @mattdm Because I am building a lens support which will be off-camera and all components has to be aligned along the optical axis. This requires the height of the sensor from the base of the camera. – karthikeyan Jul 12 '18 at 11:50
  • I still don't get that — if you're supporting the lens, the camera will come along for free. – Please Read Profile Jul 12 '18 at 12:00
  • @mattdm perhaps I'll finish my setup and share a picture to explain.i am supporting the lens not attached to the camera but aligned to the camera sensor – karthikeyan Jul 12 '18 at 13:24
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    What are you photographing that needs such an odd lens arrangement? – xiota Jul 13 '18 at 4:15
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I am using a D5200 and wish to find the height of the centre of the sensor from the base of the body.

I don't know the number, but you should be able to measure the distance easily enough. It's a good bet that the sensor is centered within the lens mounting flange, so you really only need to measure from the inside edge of the flange to the bottom of the body, and also measure the inside diameter of the flange. You can take both measurements very accurately with a vernier caliper. Add the radius of the flange (half the diameter) to the flange to base measurement, and you should have the distance to the center of the sensor.

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Usually the distance from the center of the sensor to the base of the camera isn't considered when designing a rail support because accessories such as batteries or matt boxes and lenses all add an additional unknown distance to that measurement; instead the support attached to the rail is adjustable.

Example GenusTech Rail Support:

  • DSLR

DSLR Rail

Adjustable Base

  • Video Camera

Complete Unit

Adjustable Base

By building (or buying for less than U$200) an adjustable base and rail holder you can accommodate different cameras and accessories. By using the distance from the center of a D5200 sensor to its base to design a rail holder you will be limited in the number of cameras that will fit.

If the lens is long enough to require support there's bound to be some differences in the diameters of different long lenses that aren't going to be accommodated by a non-adjustable setup.

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  • Thanks for your suggestion! I will look into making an adjustable stand. Sounds very versatile. Also, the reference images are giving me good ideas for modifying my original design! Thanks – karthikeyan Jul 9 '18 at 7:36
  • @karthikeyan - Glad to be of help. If you were to edit your answer to explain how that distance would assist your design and if you own that camera presently upon which to make physical measurements (as another answer has suggested) perhaps we could improve our answers; assisting you to choose one as your preferred answer. – Rob Jul 9 '18 at 16:18
  • I think I went with the vernier caliper. Yes I own the camera. And I did end up taking measurements! – karthikeyan Jul 9 '18 at 16:27
  • @karthikeyan I got the impression that you were intending to remove the lens from the camera and were designing and optical system to hold off-camera lens elements at the correct location along the optical axis of the image system. Is this the case? If yes, then this doesn't really answer your question, I don't think. – J... Jul 9 '18 at 17:33
  • @karthikeyan - Thanks for your reply. It seemed from the question that you were designing the device for someone else or prior to purchase, that's why you didn't know the measurement. – Rob Jul 9 '18 at 17:45
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The center of the sensor is at the same height and width of the center of the lens mount. If you search for the plane where the sensor is: There is a symbol on the body (a little circle with a long line thru it). That shows the position.

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  • oh and also the nikon f-mount has a fixed distance between f-mount and sensor. you can google for it. – Horitsu Jul 9 '18 at 4:52
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    The sensor plane mark on the body indicates the forward/back location of the sensor plane. It doesn't indicate at all where the sensor is located vertically (with respect to the tripod mount, for instance). But your point about being aligned with the center of the lens mount is spot on. – scottbb Jul 9 '18 at 16:18
  • if it was not clear: i also mean just the forward/back location of the sensor plane – Horitsu Jul 9 '18 at 19:26
  • It wasn't exactly clear to me, but after re-reading, I see your meaning. Being a plane, it can only be located front/back. Makes sense. – scottbb Jul 9 '18 at 20:08
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I would normally suggest finding the information in the Entrance Pupil Database at Panotools.org. However, unfortunately there is no entry in the table for the Nikon D5200. =(

(Leaving this answer for future reference for similar questions)

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Use an Optical Rail as the basis of your system.

The Ealing company supplies electro-optical laboratory supplies that would be suitable and affordable for this project.

All the equipment is optical laboratory (accurate) grade. Everything is adjustable. The student/economy line I suggest is currently on clearance for about half its normal price.

The TriRail optomechanical equipment short list is:

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