Homemade 35mm Adapter

Chris Black · December 10th, 2003, 09:45 AM

<<<-- The GL2 does in fact have a superb built-in macro mode. -->>>

Sure enough. I tested the gl2's macro capability ...and it's amazing ......i took a piece of paper with writing on it ... ....took off the lens hood ........and literally held the piece of paper about 1/8th of an inch from the lens ...and it focused perfectly ....crisp and clear. ....

thanks chris ..

chris

Jim Lafferty · December 10th, 2003, 10:39 AM

<<<-- Originally posted by Chris Black : <<<-- The GL2 does in fact have a superb built-in macro mode. -->>>

Sure enough. I tested the gl2's macro capability ...and it's amazing ......i took a piece of paper with writing on it ... ....took off the lens hood ........and literally held the piece of paper about 1/8th of an inch from the lens ...and it focused perfectly ....crisp and clear. ....

thanks chris ..

chris -->>>

You both seem to be missing the point, though: you cannot simultaneously engage the Gl1/Gl2's "macro mode" WHILE filling the frame with the suspended 35mm image.

You have to zoom IN, not out, in order to get the projected image large enough so that it encompasses the entire frame of your DV camera, while simultaneously remaining in focus manually. This way, you do not get vignetting or a black, circular border in your DV frame.

Auto focus will not work, as the camera is constantly receiving different information about what to focus on - the spinning disc, the image on the disc, the footage coming through the hole, etc.

I'd love to be proven wrong, and then I wouldn't have to spend $210 on a macro zoom (or $100 on an appropriate magnifying glass.)

- jim

Chris Hurd · December 10th, 2003, 10:53 AM

Indeed, GL2's macro works only at full-wide angle.

J. Clayton Stansberry · December 10th, 2003, 10:53 AM

So, will this macro function work or not?

Chris Black,
Let us know if it works with this macro function of the GL2 and the Agus35...would save many from purchasing the additional macro lens...

Chris Black · December 10th, 2003, 11:12 AM

I did a few more basic tests with the gl2 macro function. ......Like it has been pointed out, in order for the macro to work properly, you must be zoomed all the way out. But at that point .....you can literally hold your subject up against the end of the lens housing ..and it stays in focus .........so ....couldnt you just mount the camera close enough to the spinning cd ...that you wouldnt have to zoom? .... ............

the next thing i tried was .......moving the subject about 2 to 3 inches from the camera lens .........I then was able to zoom in about half of the gl2's optical range (Not sure if the camera was still in macro mode or not)....and still have the subject clearly in focus. .....I'm not sure if this would be enough zoom to eliminate the vignetting.....

I plan on building an Agus35 for my gl2 ....but it will probably be 2 or 3 weeks before I can get to it. I will definitely include details photos and descriptions of the process.

Chris

Cosmin Rotaru · December 10th, 2003, 12:25 PM

Chris, I own a GL2 (actualy the XM2 PAL version). It is imposible to zoom and focus on a 35/24mm rectangle without a close up lens. For this purpose I've used a philatelic lens.
I have another philatelic lens between the 35mm lens and the GG. Very close (aclmoest in touch) with the GG. This removes the vigneting on the GG.
http://www.utdallas.edu/library/special/wprl.gif

Chris Black · December 10th, 2003, 12:35 PM

So the question remains. Can you get the GG close enough to the lens of the gl2 (without zooming) to eliminate the vignetting?

Chris

Agus Casse · December 10th, 2003, 12:46 PM

you need a magnifying glass from the GG to the DV camera.

Aaron Koolen · December 10th, 2003, 01:26 PM

Ok, Cosmin said he used a magnifier between 35mm and GG, and Agus said between GG and camera. Which is correct? I would think that Agus' is correct cause if you magnify the 35mm image won't you lose some of the DOF?

Couple more things. Have people had more success with the GG near the lens, or near the DV camera. People seem to be doing different things here too. I would have thought you'd have to have the GG the same distance as a 35mm image place to get the correct DOF, otherwise you'll be getting more or less than real 35mm.

And, couldn't you just build a long adapter so that the GL2 can focus on the plane or is that still not possible?

Aaron

Jim Lafferty · December 10th, 2003, 01:47 PM

<<<-- Originally posted by Aaron Koolen : ...couldn't you just build a long adapter so that the GL2 can focus on the plane or is that still not possible?

Aaron -->>>

Possibly - but why would you want to? I can't imagine a benefit of a larger, more unwieldy setup.

On further note of the magnifying glass situation - larger magnifying glasses (i.e. those that match or exceed the 58mm diameter of the GL1/GL2's lens) are insignificant in their magnification power. To get a 3 or 4x magnifier, you need to either: go down in diameter (unacceptable as you will get considerable vignetting); or spend upwards of $100, with no guarantee that the lens will work appropriately (and a lot of work and a bit of risk to figure it out in the end.)

The macro zooms from Century Optics are your best bet, though they do up the cost of your adapter considerably. Be sure to get the +7 adapter, though, as this puts lens placement within 3 inches of the subject possible. +2 puts your lens 10" out. You can then use the macro function separate of your Agus35, too.

- jim

Jon Yurek · December 10th, 2003, 01:53 PM

Quote:

Couple more things. Have people had more success with the GG near the lens, or near the DV camera. People seem to be doing different things here too. I would have thought you'd have to have the GG the same distance as a 35mm image place to get the correct DOF, otherwise you'll be getting more or less than real 35mm.

People are putting the GG in different places because that's where they are focusing the image, that's all. It doesn't really matter where the GG goes in the adapter as long as you can get the SLR lens to focus on the GG and the DV camera to focus onto the GG. You may want to do it so that focusing would be more like properly focusing an SLR lens for the right distances, and that would take more work than the simple ad hoc solution that some people are likely taking here.

Quote:

And, couldn't you just build a long adapter so that the GL2 can focus on the plane or is that still not possible?

Of course, but the longer you make it the more unwieldly it will become and the less likely you are to be able to use it handheld anymore. Also, it will be harder to keep it aligned properly unless you have supports.

Agus Casse · December 10th, 2003, 01:54 PM

Ok, i will clear this doubts for once and for all..

The magnifying glass goes between the GG and the DV camera, and the GG has to be as close as possible to the DV camera until there is no vigneting.

Dont get confuse, and the best way to solve it is to find a cheap wide conversion lens, and take the first lens that indeed maginfy and a lot... that will cost ya like 35 bucks... dont find and expensive one and also you dont need one that have the exactly the same diameter, cause you zoom half way in (my camera case), so you can find a cheap wide conversion lens for any cheap dv camera, and just use the part that you need.

Keep it simple, and you will get better results :)

Luke Andrews · December 10th, 2003, 04:07 PM

OK i'm jumping in I have a done a "dry" test; frosted glass, nikon lens, XL1 and a cardboard box. No fresnel or mag glass. No moving parts I want to get a feel for everything before I move on. It really works I'll have some stills later.
My main question is, in the mini35 what all is handled in the relay lens section? How are they over coming the 7.2x magnification of 35mm lenses and 1/3" CCD's? what could we use in place of this my goal is to replace the 16X lens of my XL1 to reduce the amount of glass the image is coming thru.

great jorb Agus, when are you posting your plans?

Luke

Rob Lohman · December 10th, 2003, 04:17 PM

Well, this design basically depends on the camera lens being
in place. The XL1 is a difficult camera if you want to remove the
lens because you will have to replace it by a "relay" lens.

The 7.2x magnification is gone because the image is projected
onto the ground glass (the CD) instead of on the CCD directly.

J. Clayton Stansberry · December 10th, 2003, 04:28 PM

<<<-- Originally posted by Agus Casse : Ok, i will clear this doubts for once and for all..
Dont get confuse, and the best way to solve it is to find a cheap wide conversion lens, and take the first lens that indeed maginfy and a lot... that will cost ya like 35 bucks... dont find and expensive one and also you dont need one that have the exactly the same diameter, cause you zoom half way in (my camera case), so you can find a cheap wide conversion lens for any cheap dv camera, and just use the part that you need.
-->>>

Agus,

Just to be clear, when you say "wide conversion lens" you are talking about a Macro lens? And, you don't have to connect it directly to the camera? Could you explain this....because I think that would be a great way to connect it - put on the macro lens and there you go!?!

Thanks,
Clay

December 10th, 2003, 10:53 AM	#243
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	Indeed, GL2's macro works only at full-wide angle. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

December 10th, 2003, 10:53 AM	#244
J. Clayton Stansberry Major Player Join Date: Sep 2003 Location: Colorado Posts: 316	So, will this macro function work or not? Chris Black, Let us know if it works with this macro function of the GL2 and the Agus35...would save many from purchasing the additional macro lens... __________________ I understand everything about nothing.

December 10th, 2003, 12:25 PM	#246
Cosmin Rotaru Major Player Join Date: Feb 2003 Location: Romania, Timisoara Posts: 453	Chris, I own a GL2 (actualy the XM2 PAL version). It is imposible to zoom and focus on a 35/24mm rectangle without a close up lens. For this purpose I've used a philatelic lens. I have another philatelic lens between the 35mm lens and the GG. Very close (aclmoest in touch) with the GG. This removes the vigneting on the GG. http://www.utdallas.edu/library/special/wprl.gif __________________ Cosmin Rotaru

December 10th, 2003, 01:26 PM	#249
Aaron Koolen Trustee Join Date: Apr 2002 Location: Auckland, New Zealand Posts: 1,727	Ok, Cosmin said he used a magnifier between 35mm and GG, and Agus said between GG and camera. Which is correct? I would think that Agus' is correct cause if you magnify the 35mm image won't you lose some of the DOF? Couple more things. Have people had more success with the GG near the lens, or near the DV camera. People seem to be doing different things here too. I would have thought you'd have to have the GG the same distance as a 35mm image place to get the correct DOF, otherwise you'll be getting more or less than real 35mm. And, couldn't you just build a long adapter so that the GL2 can focus on the plane or is that still not possible? Aaron __________________ My Website Meat Free Media

December 10th, 2003, 04:17 PM	#254
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	Well, this design basically depends on the camera lens being in place. The XL1 is a difficult camera if you want to remove the lens because you will have to replace it by a "relay" lens. The 7.2x magnification is gone because the image is projected onto the ground glass (the CD) instead of on the CCD directly. __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

December 10th, 2003, 09:45 AM	#241
Chris Black New Boot Join Date: Dec 2003 Location: Corpus Christi texas Posts: 14	<<<-- The GL2 does in fact have a superb built-in macro mode. -->>> Sure enough. I tested the gl2's macro capability ...and it's amazing ......i took a piece of paper with writing on it ... ....took off the lens hood ........and literally held the piece of paper about 1/8th of an inch from the lens ...and it focused perfectly ....crisp and clear. .... thanks chris .. chris

December 10th, 2003, 10:39 AM	#242
Jim Lafferty Major Player Join Date: Dec 2003 Location: Brooklyn, NY Posts: 636	<<<-- Originally posted by Chris Black : <<<-- The GL2 does in fact have a superb built-in macro mode. -->>> Sure enough. I tested the gl2's macro capability ...and it's amazing ......i took a piece of paper with writing on it ... ....took off the lens hood ........and literally held the piece of paper about 1/8th of an inch from the lens ...and it focused perfectly ....crisp and clear. .... thanks chris .. chris -->>> You both seem to be missing the point, though: you cannot simultaneously engage the Gl1/Gl2's "macro mode" WHILE filling the frame with the suspended 35mm image. You have to zoom IN, not out, in order to get the projected image large enough so that it encompasses the entire frame of your DV camera, while simultaneously remaining in focus manually. This way, you do not get vignetting or a black, circular border in your DV frame. Auto focus will not work, as the camera is constantly receiving different information about what to focus on - the spinning disc, the image on the disc, the footage coming through the hole, etc. I'd love to be proven wrong, and then I wouldn't have to spend $210 on a macro zoom (or $100 on an appropriate magnifying glass.) - jim

December 10th, 2003, 11:12 AM	#245
Chris Black New Boot Join Date: Dec 2003 Location: Corpus Christi texas Posts: 14	I did a few more basic tests with the gl2 macro function. ......Like it has been pointed out, in order for the macro to work properly, you must be zoomed all the way out. But at that point .....you can literally hold your subject up against the end of the lens housing ..and it stays in focus .........so ....couldnt you just mount the camera close enough to the spinning cd ...that you wouldnt have to zoom? .... ............ the next thing i tried was .......moving the subject about 2 to 3 inches from the camera lens .........I then was able to zoom in about half of the gl2's optical range (Not sure if the camera was still in macro mode or not)....and still have the subject clearly in focus. .....I'm not sure if this would be enough zoom to eliminate the vignetting..... I plan on building an Agus35 for my gl2 ....but it will probably be 2 or 3 weeks before I can get to it. I will definitely include details photos and descriptions of the process. Chris

December 10th, 2003, 12:35 PM	#247
Chris Black New Boot Join Date: Dec 2003 Location: Corpus Christi texas Posts: 14	So the question remains. Can you get the GG close enough to the lens of the gl2 (without zooming) to eliminate the vignetting? Chris

December 10th, 2003, 12:46 PM	#248
Agus Casse Major Player Join Date: Jul 2003 Location: Guatemala Posts: 322	you need a magnifying glass from the GG to the DV camera.

December 10th, 2003, 01:47 PM	#250
Jim Lafferty Major Player Join Date: Dec 2003 Location: Brooklyn, NY Posts: 636	<<<-- Originally posted by Aaron Koolen : ...couldn't you just build a long adapter so that the GL2 can focus on the plane or is that still not possible? Aaron -->>> Possibly - but why would you want to? I can't imagine a benefit of a larger, more unwieldy setup. On further note of the magnifying glass situation - larger magnifying glasses (i.e. those that match or exceed the 58mm diameter of the GL1/GL2's lens) are insignificant in their magnification power. To get a 3 or 4x magnifier, you need to either: go down in diameter (unacceptable as you will get considerable vignetting); or spend upwards of $100, with no guarantee that the lens will work appropriately (and a lot of work and a bit of risk to figure it out in the end.) The macro zooms from Century Optics are your best bet, though they do up the cost of your adapter considerably. Be sure to get the +7 adapter, though, as this puts lens placement within 3 inches of the subject possible. +2 puts your lens 10" out. You can then use the macro function separate of your Agus35, too. - jim

December 10th, 2003, 01:54 PM	#252
Agus Casse Major Player Join Date: Jul 2003 Location: Guatemala Posts: 322	Ok, i will clear this doubts for once and for all.. The magnifying glass goes between the GG and the DV camera, and the GG has to be as close as possible to the DV camera until there is no vigneting. Dont get confuse, and the best way to solve it is to find a cheap wide conversion lens, and take the first lens that indeed maginfy and a lot... that will cost ya like 35 bucks... dont find and expensive one and also you dont need one that have the exactly the same diameter, cause you zoom half way in (my camera case), so you can find a cheap wide conversion lens for any cheap dv camera, and just use the part that you need. Keep it simple, and you will get better results :)

December 10th, 2003, 04:07 PM	#253
Luke Andrews New Boot Join Date: Jun 2003 Location: Medina, OH Posts: 13	OK i'm jumping in I have a done a "dry" test; frosted glass, nikon lens, XL1 and a cardboard box. No fresnel or mag glass. No moving parts I want to get a feel for everything before I move on. It really works I'll have some stills later. My main question is, in the mini35 what all is handled in the relay lens section? How are they over coming the 7.2x magnification of 35mm lenses and 1/3" CCD's? what could we use in place of this my goal is to replace the 16X lens of my XL1 to reduce the amount of glass the image is coming thru. great jorb Agus, when are you posting your plans? Luke

December 10th, 2003, 04:28 PM	#255
J. Clayton Stansberry Major Player Join Date: Sep 2003 Location: Colorado Posts: 316	<<<-- Originally posted by Agus Casse : Ok, i will clear this doubts for once and for all.. Dont get confuse, and the best way to solve it is to find a cheap wide conversion lens, and take the first lens that indeed maginfy and a lot... that will cost ya like 35 bucks... dont find and expensive one and also you dont need one that have the exactly the same diameter, cause you zoom half way in (my camera case), so you can find a cheap wide conversion lens for any cheap dv camera, and just use the part that you need. -->>> Agus, Just to be clear, when you say "wide conversion lens" you are talking about a Macro lens? And, you don't have to connect it directly to the camera? Could you explain this....because I think that would be a great way to connect it - put on the macro lens and there you go!?! Thanks, Clay __________________ I understand everything about nothing.