The Pappas Lens System at DVinfo.net

October 15th, 2002, 10:12 AM

Hello all...

We are trying to achieve a very shallow depth of field similar to that of an 85mm prime lens for 16mm/ 35mm cameras. Basically, we want to have our subject 10-15 feet away, & have background fall off to mush, just like a 85mm prime. Per the Pappas System article on the Watchdog site, we have the EF lens adapter, a 15mm EOS lens, and what we thought would work for a .6x wide angle adapter. After assembling these components together, we are finding that we have no more or less depth of field than what we can achieve with the 16x standard lens. Looking at the pictures of the Pappas system, we seem to have all of the "same" components - Except for the .42x wide angle adapter. Our .6x adapter is a Century Optics wide angle add-on glass element, whereas in the pictures of the Pappas system, the .42x adapter appears to be yet ANOTHER LENS barrel. What is that lens adapter and more importantly, does this system allow for a shallow depth of field?

The moonkp guys

Jeff Donald · October 15th, 2002, 04:05 PM

Please read this thread I started recently

http://www.dvinfo.net/conf/showthread.php?s=&threadid=3926

If you have questions reguarding DoF and how it applies to your particular set-up, post on either thread and I'll be happy to answer any questions. the following threads may be of interest also

http://www.dvinfo.net/conf/showthread.php?s=&threadid=4091

http://www.dvinfo.net/conf/showthread.php?s=&threadid=4103

Jeff

Adrian Douglas · October 15th, 2002, 08:33 PM

Michael's lens set up was a way to allow for true manual focus for pull and rack focus effects. His system does not affect DOF as it has little to do with the lens and more to do with the size of the CCD. Read Jeff's threads and it will explain it all.

Chris Hurd · October 18th, 2002, 05:09 AM

I should probably make a note on that page (about Michael's set-up) that it was written early in 1998, prior to the availability of the Canon 14x lens. No doubt about it, that article is way out of date now and is still online only as a matter of historical record.

After re-reading the article, it's important to note that it makes no claims at all about depth-of-field. It's strictly about precise focus control.

The Watchdog is going to be updated and taken out of frames shortly, and I suppose that would be a good time to go back through and add dates to the articles... plus, it looks like I'll need to add a disclaimer to that particular article, about how it's been outdated since the introduction of the first Canon manual lens back in the Fall of 1998. Hope this helps,

Andre De Clercq · October 19th, 2002, 04:31 AM

Whatever lens you use, whatever shooting distance you choose, for a given CCD size and F-number, DOF will not change if the (filmed) size of the objects remains fixed. Other optical means have been posted in the past.

October 15th, 2002, 10:12 AM	#1
moonkpguys Posts: n/a	The Pappas Lens System Hello all... We are trying to achieve a very shallow depth of field similar to that of an 85mm prime lens for 16mm/ 35mm cameras. Basically, we want to have our subject 10-15 feet away, & have background fall off to mush, just like a 85mm prime. Per the Pappas System article on the Watchdog site, we have the EF lens adapter, a 15mm EOS lens, and what we thought would work for a .6x wide angle adapter. After assembling these components together, we are finding that we have no more or less depth of field than what we can achieve with the 16x standard lens. Looking at the pictures of the Pappas system, we seem to have all of the "same" components - Except for the .42x wide angle adapter. Our .6x adapter is a Century Optics wide angle add-on glass element, whereas in the pictures of the Pappas system, the .42x adapter appears to be yet ANOTHER LENS barrel. What is that lens adapter and more importantly, does this system allow for a shallow depth of field? The moonkp guys

October 15th, 2002, 08:33 PM	#3
Adrian Douglas Trustee Join Date: Oct 2001 Location: Chigasaki, Japan. Posts: 1,660	Michael's lens set up was a way to allow for true manual focus for pull and rack focus effects. His system does not affect DOF as it has little to do with the lens and more to do with the size of the CCD. Read Jeff's threads and it will explain it all. __________________ Adrian DVInfo.net Search for quick answers Where to buy? From the best in the business...DVInfo.net sponsors

October 18th, 2002, 05:09 AM	#4
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	I should probably make a note on that page (about Michael's set-up) that it was written early in 1998, prior to the availability of the Canon 14x lens. No doubt about it, that article is way out of date now and is still online only as a matter of historical record. After re-reading the article, it's important to note that it makes no claims at all about depth-of-field. It's strictly about precise focus control. The Watchdog is going to be updated and taken out of frames shortly, and I suppose that would be a good time to go back through and add dates to the articles... plus, it looks like I'll need to add a disclaimer to that particular article, about how it's been outdated since the introduction of the first Canon manual lens back in the Fall of 1998. Hope this helps, __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

October 15th, 2002, 04:05 PM	#2
Jeff Donald Warden Join Date: Mar 2002 Location: Clearwater, FL Posts: 8,287	Please read this thread I started recently http://www.dvinfo.net/conf/showthread.php?s=&threadid=3926 If you have questions reguarding DoF and how it applies to your particular set-up, post on either thread and I'll be happy to answer any questions. the following threads may be of interest also http://www.dvinfo.net/conf/showthread.php?s=&threadid=4091 http://www.dvinfo.net/conf/showthread.php?s=&threadid=4103 Jeff

October 19th, 2002, 04:31 AM	#5
Andre De Clercq Major Player Join Date: Sep 2002 Location: Belgium Posts: 804	Whatever lens you use, whatever shooting distance you choose, for a given CCD size and F-number, DOF will not change if the (filmed) size of the objects remains fixed. Other optical means have been posted in the past.