Talk:Entrance Pupil Database

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Number of picture for 360 / Degrees between picture


Thanks for adding your measurements.





Hi Richard,



Tripod Mount Length L1



Thoughts ?




Third party lenses: Tripod mount to NPP : L, L1 and L2.





I don't have any of these lenses to accurately measure myself, but found some other sources of lens data. I will do some editing and see if I can come up with a suitable table format. --Plattro (talk) 17:24, 7 July 2013 (CEST)

Improved the table accordingly, I think it's better now. Assuming most are with either Nikon or Canon, the difference is just 2.5mm, so the data isn't useless. Most people's measurements accuracy is within this range, and the value is at least a good starting point.







Canon 5d Mark III




Panasonic Lumix LX3 Lens Base


Sigma 8mm F4.0 EX




Entrance pupil shift

Fisheyes and wide angles

A number of fisheye and wide lenses show strong entrance pupil shift (See the animations on the web page by Pierre Toscani!!) by angle from center.

The Nikon 10.5 and 16mm fisheye's entrance pupil shifts by around 15mm, the ideal LPP point for panoramas is therefore a bit of a compromise, depending on the amount of image overlap and I don't know what else. The Nikon 14mm f2.8D and other wide angles do this too

Internal vignetting

I recently noticed some people's measurements conflicted with mine, I am however quite confident in the accuracy of my measurement setup now. The reason I found is that entrance pupil sometimes shifts with the aperture wide open to to internal vignetting away from the aperture,

I now always measure by observing the aperture from the front and with the lens stopped down. Measurements made with the lens wide open (Especially with the parallax method) may therefore differ from mine. This means the ideal NPP could differ slightly if you shoot wide open.

The Nikkor AF 50mm f1.8D does this noticeably. The apparent aperture (50/1.8=27mm) is bigger than the shift, so I expect the difference is smaller than the DOF and not noticeable anyway.

In the above cases I have tried to make the appropriate setting to use clear in the descriptions

Distance between the sensor to the nodal point.

I'am Daniele,, I am following the Entrance Pupil database from some time but I found, I think, a little bug in the way we consider the various distances. Mainly I think that is not a proper way of measure that from the lens mount border to the center of the stative mount screw, because the sensor is not located in that point, but little back.

To let all the measures be usable it need to calculate also the distances from the mount screw and the sensor surface.

The sensor position is of no interest here. The entrance pupil (the no-parallax-point) is a property of the lens only. The sensor position doesn't alter this property in any way. So if you want to adjust your panoramic tripod head, you need the distance from the tripod mounting screw to the rotation axis of the head, that's why those measurements are used here. --Erik Krause (talk) 19:53, 25 October 2016 (UTC)

What I mean is that a Canon EOS 7D using a Canon 15-85 lens at 15mm the Entrance Pupil is at 100mm from the mounting screw to the lens mount border, but in a EOS 550D the position can be different. So, the measure are valid only for the specific lens, specific camera at specific focal lenght. Correct??

The lens measurements are valid for the specific lens at a given focal length, the camera measurements are for the camera. Add both to get the value for your combination. --Erik Krause (talk) 19:55, 25 October 2016 (UTC)

Today I insert the Entrance Pupil Point position for the Canon 15-85mm lens, that was missing from the list. I would like to know if someome else take this measures, with the 7D and with other Canon body, just to compare the results and better understand the question.