Fujinon CCTV lens as a relay lens for DOF adaptor? at DVinfo.net

Toenis Liivamaegi · December 12th, 2006, 07:54 AM

How bad is the image quality on JVC HD100/110 from good CCTV lenses when used as relay lens in DOF adaptor configuration, instead of original/supplied Fujinon TV lens?
I wonder that maybe 1.5 megapixel lens are good enough?

>> This lens is specd exactly as needed if only the image quality would be OK.
Pay attention to M.O.D. and FOV with 1/3" sensor.

As 1/3" mount converts c-mount to macro then this could be the ideal relay lens for HD100.

Can someone help me out?
T

Chris Hurd · December 12th, 2006, 10:06 AM

Moved from JVC Pro HD to Alternative Imaging Methods.

Ben Winter · December 12th, 2006, 10:49 AM

I don't think the issue here is image quality...the minimum focusing distance is "around" .15 meters. That's not very close, in adapter terms...

Toenis Liivamaegi · December 12th, 2006, 11:27 AM

1/3" mount flange distance is longer than c-mount`s thus allowing closer focusing.

JVC HD100 1/3" lens mount flange distance is probably 31mm and the C-mount flange distance is 17.56mm in the other hand. That alone should result in much closer focusing distance already not to mention that vignette safe distance from frensel focusing screen should stay around 50mm.

Can someone enlighten us about how significantly extension tubes for example shorten the focusing distance?
Maybe 31mm versus 17.56 shortens the minimum object distance about to half?

People here have overcome much grater MOD problems than that.

Thanks in advance,
T

Bob Hart · December 12th, 2006, 03:51 PM

On to a 1/3" security camera I have tried a 25mm C-mount f1.8 Cosmicar lens, offset forward of normal flange by about 6 to 8mm to frame 24mm x 18mm at about 120mm from front of lens.

In my limited use of the JVC with an adaptor, the cam appears to be sensitive to very tight relay apertures. (refraction??)

Eric Ramahatra · March 18th, 2007, 10:55 AM

did someone tried this lens as relay ? is it working ? (want to try it with redrock M2)

December 12th, 2006, 07:54 AM	#1
Toenis Liivamaegi Major Player Join Date: Nov 2005 Location: Tartu, Estonia Posts: 579	Fujinon CCTV lens on a JVC HD100/110 as a relay lens for DOF adaptor? How bad is the image quality on JVC HD100/110 from good CCTV lenses when used as relay lens in DOF adaptor configuration, instead of original/supplied Fujinon TV lens? I wonder that maybe 1.5 megapixel lens are good enough? >> This lens is specd exactly as needed if only the image quality would be OK. Pay attention to M.O.D. and FOV with 1/3" sensor. As 1/3" mount converts c-mount to macro then this could be the ideal relay lens for HD100. Can someone help me out? T Last edited by Toenis Liivamaegi; December 12th, 2006 at 11:55 AM. Reason: added camcorder name as topic was moved

December 12th, 2006, 10:06 AM	#2
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	Moved from JVC Pro HD to Alternative Imaging Methods. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

December 12th, 2006, 10:49 AM	#3
Ben Winter Trustee Join Date: Jun 2005 Location: Hollywood, CA Posts: 1,675 Images: 1	I don't think the issue here is image quality...the minimum focusing distance is "around" .15 meters. That's not very close, in adapter terms... __________________ BenWinter.com

December 12th, 2006, 11:27 AM	#4
Toenis Liivamaegi Major Player Join Date: Nov 2005 Location: Tartu, Estonia Posts: 579	1/3" mount flange distance is longer than c-mount`s thus allowing closer focusing. JVC HD100 1/3" lens mount flange distance is probably 31mm and the C-mount flange distance is 17.56mm in the other hand. That alone should result in much closer focusing distance already not to mention that vignette safe distance from frensel focusing screen should stay around 50mm. Can someone enlighten us about how significantly extension tubes for example shorten the focusing distance? Maybe 31mm versus 17.56 shortens the minimum object distance about to half? People here have overcome much grater MOD problems than that. Thanks in advance, T Last edited by Toenis Liivamaegi; December 12th, 2006 at 11:57 AM.

December 12th, 2006, 03:51 PM	#5
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	On to a 1/3" security camera I have tried a 25mm C-mount f1.8 Cosmicar lens, offset forward of normal flange by about 6 to 8mm to frame 24mm x 18mm at about 120mm from front of lens. In my limited use of the JVC with an adaptor, the cam appears to be sensitive to very tight relay apertures. (refraction??)

March 18th, 2007, 10:55 AM	#6
Eric Ramahatra Regular Crew Join Date: Mar 2007 Location: Paris Posts: 72	did someone tried this lens as relay ? is it working ? (want to try it with redrock M2)