Nikon Mount on BM4k URSA PL at DVinfo.net

Bob Hart · June 15th, 2017, 03:45 AM

Why?

I have a comprehensive set of fast AIS Nikons, which I can't hope to replace cost-wise. Time to get started and draw the proper design and devise the method for least waste of metal stock. The little guys in Dongguan could probably dream about it the night before, design it, make it, hard-chrome finish it and package it before I can and sell it for less than the cost of the metal stock too. - So onward to hunching over the machine and looking like Quasimodo by the end of it all.

There is probably the "doing it because I can, not necessarily because I should" factor at play here as well.

Bob Hart · June 15th, 2017, 11:06 AM

A little furthur info on the process.

Bob Hart · June 17th, 2017, 10:41 AM

An update on the design diagram

Bob Hart · June 17th, 2017, 10:45 AM

Sort of how it will look. The flowcast machined bronze adaptor piece will have the Nikon F-Mount attached to it as it would be to a Nikon camera and the adaptor piece attached to the intermediate BM adaptor piece for the PL-Mount in place of the PL-Mount.

Failed upload will try again. No good again will try later.

Bob Hart · June 23rd, 2017, 10:19 PM

It looks like image upload is permanently impossible with my current computer. It has some idiosyncracies.

Here is a link to some test footage with the Nikons on the BM URSA 4K PL with custom mount.

It was shot in "film" setting which requires colour grading afterwards. The images have not been graded. I deliberately shot in an hostile late afternoon overcast environment against the sun to drive any defects to the surface. So far the results have been encouraging. Professional cine lenses would be better but the Nikons will do in the meantime.

Bob Hart · July 3rd, 2017, 10:49 AM

Here is a sample from the footage shot of the Leeuwin refit.

Bob Hart · August 14th, 2017, 11:19 AM

Here's another iteration of the Nikon mount arrangement. I have added a 0.71 "Ultra" speedbooster optic to the camera throat which yields a wider image to the sensor. In this instance, the flange face of the Nikon lens mount has to be moved 4.2mm closer to the focal plane. It is doable with Nikons but not with Canon EF or PL-Mount.

Bob Hart · August 14th, 2017, 11:27 AM

These two images convey the difference between the direct-to-sensor image and the image via the speedbooster optical cell. The chair I forgot to remove after I used it to sit on while I removed the optical cell and reset the mount. The lens aperture setting was left the same.

Here is a quick test shot to a HD recorder outboard of the camera. I did not have a CFast2 card handy at the time.

https://www.youtube.com/watch?v=TQu_...ature=youtu.be

Bob Hart · August 14th, 2017, 11:31 AM

I tried to embed the clip but it won't go for some reason.

June 15th, 2017, 03:45 AM	#1
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Nikon Mount on BM4k URSA PL Why? I have a comprehensive set of fast AIS Nikons, which I can't hope to replace cost-wise. Time to get started and draw the proper design and devise the method for least waste of metal stock. The little guys in Dongguan could probably dream about it the night before, design it, make it, hard-chrome finish it and package it before I can and sell it for less than the cost of the metal stock too. - So onward to hunching over the machine and looking like Quasimodo by the end of it all. There is probably the "doing it because I can, not necessarily because I should" factor at play here as well. Attached Thumbnails Last edited by Bob Hart; June 15th, 2017 at 03:47 AM. Reason: add pic

June 15th, 2017, 11:06 AM	#2
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Re: Nikon Mount on BM4k URSA PL A little furthur info on the process. Attached Thumbnails

June 17th, 2017, 10:41 AM	#3
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Re: Nikon Mount on BM4k URSA PL An update on the design diagram Attached Thumbnails

June 17th, 2017, 10:45 AM	#4
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Re: Nikon Mount on BM4k URSA PL Sort of how it will look. The flowcast machined bronze adaptor piece will have the Nikon F-Mount attached to it as it would be to a Nikon camera and the adaptor piece attached to the intermediate BM adaptor piece for the PL-Mount in place of the PL-Mount. Failed upload will try again. No good again will try later.

June 23rd, 2017, 10:19 PM	#5
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Re: Nikon Mount on BM4k URSA PL It looks like image upload is permanently impossible with my current computer. It has some idiosyncracies. Here is a link to some test footage with the Nikons on the BM URSA 4K PL with custom mount. It was shot in "film" setting which requires colour grading afterwards. The images have not been graded. I deliberately shot in an hostile late afternoon overcast environment against the sun to drive any defects to the surface. So far the results have been encouraging. Professional cine lenses would be better but the Nikons will do in the meantime. NIKONS ON MODIFIED URSA4KV1PL - YouTube

July 3rd, 2017, 10:49 AM	#6
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Re: Nikon Mount on BM4k URSA PL Here is a sample from the footage shot of the Leeuwin refit. CAMP PACIFICA SHIP RESCUE RENDER TEST - YouTube LEEUWIN TESTS 30JUN - YouTube

August 14th, 2017, 11:19 AM	#7
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Re: Nikon Mount on BM4k URSA PL Here's another iteration of the Nikon mount arrangement. I have added a 0.71 "Ultra" speedbooster optic to the camera throat which yields a wider image to the sensor. In this instance, the flange face of the Nikon lens mount has to be moved 4.2mm closer to the focal plane. It is doable with Nikons but not with Canon EF or PL-Mount. Attached Thumbnails Last edited by Bob Hart; August 14th, 2017 at 11:23 AM. Reason: added text

August 14th, 2017, 11:27 AM	#8
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Re: Nikon Mount on BM4k URSA PL These two images convey the difference between the direct-to-sensor image and the image via the speedbooster optical cell. The chair I forgot to remove after I used it to sit on while I removed the optical cell and reset the mount. The lens aperture setting was left the same. Here is a quick test shot to a HD recorder outboard of the camera. I did not have a CFast2 card handy at the time. https://www.youtube.com/watch?v=TQu_...ature=youtu.be Attached Thumbnails Last edited by Bob Hart; August 14th, 2017 at 11:30 AM. Reason: error

August 14th, 2017, 11:31 AM	#9
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Re: Nikon Mount on BM4k URSA PL I tried to embed the clip but it won't go for some reason.