Matte Box and PD 170 Lens Issues at DVinfo.net

Hugh DiMauro · January 20th, 2005, 09:26 AM

I've been reading about PD 170 owners complaining that their lenses have become slightly "askew" at the rear, causing focus distortion. I'd like to know if using a matte box (in particular, a Chroszeil 4 X 4) without the rods will put undue strain on the front of the lens causing the rear of the lens to pull away from the camera body.

Mike Rehmus · January 20th, 2005, 09:37 AM

I think the fact that you are asking, answers the question.

The lens is largely plastic and even if it were all metal, if you hang a large weight on the front, yes, you can distort the lens. Probably permanently (in the case of plastic) if you leave the load on it.

Hugh DiMauro · January 20th, 2005, 09:56 AM

Thanks for your prompt reply. So then, if, at some time in the future I want to use filters with the matte box, I should get the rods?

Mike Rehmus · January 20th, 2005, 10:00 AM

I wouldn't put the matte box on there if it weighs more than a few ounces without the rods.

The other consideration is what happens if you bumpt the matte box when you don't have rods installed. The force applied to the lens and lens mount is increased because of the longer lever arm represented by the lens and matte box.

If you notice, the film-camera folks are very careful of their lens setups and they, for the most part, have all-metal lens bodies.

James Connors · January 21st, 2005, 06:45 AM

Props for this thread, convinced me even more to add the Century Optics Mattebox onto my wishlist, even tho its really expensive over here (around $800 !).

January 20th, 2005, 09:26 AM	#1
Hugh DiMauro Trustee Join Date: Jun 2003 Location: Central Florida Posts: 1,205	Matte Box and PD 170 Lens Issues I've been reading about PD 170 owners complaining that their lenses have become slightly "askew" at the rear, causing focus distortion. I'd like to know if using a matte box (in particular, a Chroszeil 4 X 4) without the rods will put undue strain on the front of the lens causing the rear of the lens to pull away from the camera body. __________________ Interesting, if true. And interesting anyway.

January 20th, 2005, 09:37 AM	#2
Mike Rehmus Wrangler Join Date: May 2002 Location: Vallejo, California Posts: 4,049	I think the fact that you are asking, answers the question. The lens is largely plastic and even if it were all metal, if you hang a large weight on the front, yes, you can distort the lens. Probably permanently (in the case of plastic) if you leave the load on it. __________________ Mike Rehmus Hey, I can see the carrot at the end of the tunnel!

January 20th, 2005, 09:56 AM	#3
Hugh DiMauro Trustee Join Date: Jun 2003 Location: Central Florida Posts: 1,205	Thanks for your prompt reply. So then, if, at some time in the future I want to use filters with the matte box, I should get the rods? __________________ Interesting, if true. And interesting anyway.

January 20th, 2005, 10:00 AM	#4
Mike Rehmus Wrangler Join Date: May 2002 Location: Vallejo, California Posts: 4,049	I wouldn't put the matte box on there if it weighs more than a few ounces without the rods. The other consideration is what happens if you bumpt the matte box when you don't have rods installed. The force applied to the lens and lens mount is increased because of the longer lever arm represented by the lens and matte box. If you notice, the film-camera folks are very careful of their lens setups and they, for the most part, have all-metal lens bodies. __________________ Mike Rehmus Hey, I can see the carrot at the end of the tunnel!

January 21st, 2005, 06:45 AM	#5
James Connors Major Player Join Date: Jan 2005 Location: Cardiff, UK Posts: 223	Props for this thread, convinced me even more to add the Century Optics Mattebox onto my wishlist, even tho its really expensive over here (around $800 !).