Questions on 35mm Adapters at DVinfo.net

Douglas Joseph · March 17th, 2006, 01:59 AM

Hello, cyber-surfer-monger-parrots!

I'm gonna be blunt; no beating around the bush. I don't understand how a 35mm adapter functions (I just recently discovered them). I was told that there is no quality lost while using a 35mm adapter. How can there not be? I have a Canon XL-2, and If I were to use a 50mm lens, instead of the 20x, wouldn't there be aberation to the picture quality? Assuming that the 50mm isn't a finer glass. Or is the 20x lens out of the equation? Also, I was told that only film SLR lens can be used, not digital. Why is that? Film SLR lens are compatible with digital cameras... I'm completely lost when it comes to this. Perhaps someone can explain the basic fundamentals of a 35mm adapter, because I have no clue. I think that's why I'm having trouble understanding them, because I don't know the basics. I'm definitely insterested in purchasing one (I saw some test footage) I want a better shallow depth of field; this seems to be the route to go.

All help will be greatly appreacited
Thanks in advance, guys.

Peace and Grace in abundance.

D.C. Joseph,
Reportin' out

Rich Hibner · March 17th, 2006, 03:12 AM

http://www.holyzoo.com/content/35mm/...vie_500kbs.mov

I was always told to go here if you wanted
to learn about a 35mm adapter.
This will get you on your feet.

Douglas Joseph · March 17th, 2006, 11:26 AM

That was pretty funny, but not very insightful...

Ben Winter · March 17th, 2006, 11:55 AM

http://en.wikipedia.org/wiki/Depth_of_field_adapter

Rich Hibner · March 17th, 2006, 11:56 AM

Yeah, I know...happened to me, so I'm just passing it along.

Dennis Wood · March 17th, 2006, 01:06 PM

This is from the FAQ I'm putting together:

A 35mm lens adapter allows an image from a 35mm lens to be captured either directly for framing purposes, or attached to a video camera. By capturing this image, you can achieve very shallow depth of field. You thus have the ability to direct your viewers' attention to elements in your shot to a far greater degree than just using your video camera. With all the other important elements of a film shoot (composition, lighting, sound etc.), you can achieve a very cinematic look.

The 35mm lens image is projected onto an intermediate screen, and this image is captured by the video camera. Your video camera is zoomed, and focus manually locked, to frame the intermediate screen's image. This is called back focus. From that point on, all focus, zoom and framing is handled by the 35mm lens you are using. Your video camera's focus and zoom is not touched. The image captured by your camera is upside down and must be corrected in post. Alternatively you can flip the camera and record upside down.

Most 35mm adapters out there lose from 1.5 to 3 F/stops in the field with an F1.4 50mm lens attached. For many video cameras, particularly indoors, you may need to add 1000 watts or more of light. Engineered diffusers in the proper configuration can reduce this light loss to around 1 F/stop.

Winston Vargas · April 2nd, 2006, 10:44 AM

I built a film adapter as they are called. I did not use the 35mm format. I used a medium format lens. My groundglass is 2 1/4 x 1 5/8 almost twice the size of a 35mm frame. The whole idea of these adapters is to allow you to control your Depth of Field. The adapter is only as good as the grounglass. I have built a few with different groundglass and they all have different qualities. There is an image loss, how can there not be when you are filming an image off a groundglass. The image loss is the quality that one looks for because video is too sharp and it looks like live tv. The industry has been trying to make video look like film for aver 40 years. I started shooting video in 1971 so I have seen the changes and we are getting close. So there is no mystery to these adapters. My theory is that the larger the groundglass the better the final image. I am using mine with the dvx100.

Quote:

Originally Posted by Douglas Joseph

Hello, cyber-surfer-monger-parrots!

I'm gonna be blunt; no beating around the bush. I don't understand how a 35mm adapter functions (I just recently discovered them). I was told that there is no quality lost while using a 35mm adapter. How can there not be? I have a Canon XL-2, and If I were to use a 50mm lens, instead of the 20x, wouldn't there be aberation to the picture quality? Assuming that the 50mm isn't a finer glass. Or is the 20x lens out of the equation? Also, I was told that only film SLR lens can be used, not digital. Why is that? Film SLR lens are compatible with digital cameras... I'm completely lost when it comes to this. Perhaps someone can explain the basic fundamentals of a 35mm adapter, because I have no clue. I think that's why I'm having trouble understanding them, because I don't know the basics. I'm definitely insterested in purchasing one (I saw some test footage) I want a better shallow depth of field; this seems to be the route to go.

All help will be greatly appreacited
Thanks in advance, guys.

Peace and Grace in abundance.

D.C. Joseph,
Reportin' out

Brian J. Harris · April 15th, 2006, 07:38 AM

Hello Winston,

I read a few posts about your adapter on dvxuser and here. I saw the photos on John Benton's site before the site's bandwidth was exceeded. Are you planning to produce and sell your adapter? If so, do you have an approximate time frame when production will ramp up and orders will be taken?

John indicated he was impressed with your adapter. I know it was developed for the DVX, but I hope it will be compatible with other cameras, since I have an XL2.

I would love to see some footage if you have any available. If you are looking for a temporary hosting solution, www.filefront.com provides a fairly reliable, free file hosting service.

Any info will be greatly appreciated.

March 17th, 2006, 01:59 AM	#1
Douglas Joseph Major Player Join Date: Oct 2005 Location: Zanesville OH Posts: 205	Questions on 35mm Adapters Hello, cyber-surfer-monger-parrots! I'm gonna be blunt; no beating around the bush. I don't understand how a 35mm adapter functions (I just recently discovered them). I was told that there is no quality lost while using a 35mm adapter. How can there not be? I have a Canon XL-2, and If I were to use a 50mm lens, instead of the 20x, wouldn't there be aberation to the picture quality? Assuming that the 50mm isn't a finer glass. Or is the 20x lens out of the equation? Also, I was told that only film SLR lens can be used, not digital. Why is that? Film SLR lens are compatible with digital cameras... I'm completely lost when it comes to this. Perhaps someone can explain the basic fundamentals of a 35mm adapter, because I have no clue. I think that's why I'm having trouble understanding them, because I don't know the basics. I'm definitely insterested in purchasing one (I saw some test footage) I want a better shallow depth of field; this seems to be the route to go. All help will be greatly appreacited Thanks in advance, guys. Peace and Grace in abundance. D.C. Joseph, Reportin' out __________________ "Warriors... Come out to play..." www.importexporthd.com

March 17th, 2006, 11:26 AM	#3
Douglas Joseph Major Player Join Date: Oct 2005 Location: Zanesville OH Posts: 205	That was pretty funny, but not very insightful... __________________ "Warriors... Come out to play..." www.importexporthd.com

March 17th, 2006, 11:55 AM	#4
Ben Winter Trustee Join Date: Jun 2005 Location: Hollywood, CA Posts: 1,675 Images: 1	http://en.wikipedia.org/wiki/Depth_of_field_adapter __________________ BenWinter.com

April 15th, 2006, 07:38 AM	#8
Brian J. Harris Regular Crew Join Date: Jan 2006 Location: Greenbrier, TN Posts: 89	Hello Winston, I read a few posts about your adapter on dvxuser and here. I saw the photos on John Benton's site before the site's bandwidth was exceeded. Are you planning to produce and sell your adapter? If so, do you have an approximate time frame when production will ramp up and orders will be taken? John indicated he was impressed with your adapter. I know it was developed for the DVX, but I hope it will be compatible with other cameras, since I have an XL2. I would love to see some footage if you have any available. If you are looking for a temporary hosting solution, www.filefront.com provides a fairly reliable, free file hosting service. Any info will be greatly appreciated. __________________ Thanks, Brian www.naturefootage.com

March 17th, 2006, 03:12 AM	#2
Rich Hibner Major Player Join Date: Jan 2006 Posts: 218 Images: 1	http://www.holyzoo.com/content/35mm/...vie_500kbs.mov I was always told to go here if you wanted to learn about a 35mm adapter. This will get you on your feet.

March 17th, 2006, 11:56 AM	#5
Rich Hibner Major Player Join Date: Jan 2006 Posts: 218 Images: 1	Yeah, I know...happened to me, so I'm just passing it along.

March 17th, 2006, 01:06 PM	#6
Dennis Wood Major Player Join Date: Mar 2005 Location: Ontario, Canada Posts: 916	This is from the FAQ I'm putting together: A 35mm lens adapter allows an image from a 35mm lens to be captured either directly for framing purposes, or attached to a video camera. By capturing this image, you can achieve very shallow depth of field. You thus have the ability to direct your viewers' attention to elements in your shot to a far greater degree than just using your video camera. With all the other important elements of a film shoot (composition, lighting, sound etc.), you can achieve a very cinematic look. The 35mm lens image is projected onto an intermediate screen, and this image is captured by the video camera. Your video camera is zoomed, and focus manually locked, to frame the intermediate screen's image. This is called back focus. From that point on, all focus, zoom and framing is handled by the 35mm lens you are using. Your video camera's focus and zoom is not touched. The image captured by your camera is upside down and must be corrected in post. Alternatively you can flip the camera and record upside down. Most 35mm adapters out there lose from 1.5 to 3 F/stops in the field with an F1.4 50mm lens attached. For many video cameras, particularly indoors, you may need to add 1000 watts or more of light. Engineered diffusers in the proper configuration can reduce this light loss to around 1 F/stop.