Homemade 35mm Adapter

Bob Hart · February 7th, 2004, 05:44 AM

Taylor.

Good looking pictures.

The blue band off edge of the white shirt? Is that an effect normal to your camera in high contrast situations or instead maybe an off-axis prime lens on your Agus. The lens should be guaranteed square-on due to the construction method if this has been carefully done, so that leaves only the centering of the lens relative to the camcorder lens.

Interestingly, the tripod base mount screw on the Canon camera in your construction image, appears that like the Sony PD150, it is offset to right relative to the camcorder lens centreline. I read somewhere that Canon make the PD150 lens sets. True or false I don't know.

It would be interesting to know if the centre axis of the camcorder lens falls on the centre of the CCDs or slightly off-centre like the Sony. To find out, zoom back until you get a vignette from the close-up lens if it does this.

If the vignette is offset in the viewfinder, then you might get a slightly better result if you re-align your Agus and camcorder for the centre of your projected image on the CD to be at the centre of your vignette before you zoom in, rather than at actual centre of your viewfinder image. This may help any smearing but might be at expense of having a stronger darker area down one side.

This is all only just a maybe and possibly unhelpful speculation so ignore at will.

Filip Kovcin · February 7th, 2004, 07:30 AM

Isaiah or taylor's pictures?

as i understan these are Isaiah's pictures, and taylor is just kind to host it. right?

filip

Taylor Moore · February 7th, 2004, 10:32 AM

I am merely an observer a hoster...not creator.
The great images are Isaiah's.....

Brett Erskine · February 7th, 2004, 01:09 PM

Bob the problem he's having is due to chroma aberration. To solve it you need a (....alright everyone say it with me again)...ACHROMAT macro!

Alright thats it! ;-) For the sake of my sanity Im not repeating myself again and again anymore.

From now on "RMPP" stands for Read My Previous Post.

Taylor Moore · February 7th, 2004, 01:12 PM

Brett have you had any luck finding a good inexpensive "Achromat macro" for the DVX yet/ Centurys is just so damn expensive...

Barry Green · February 7th, 2004, 05:02 PM

<<<-- Originally posted by Seth Richter : Is it possible to use the formula agus35 to make two, for even more focal length?

camera|agus35|agus35

I know that the light loss would be significant, but, it would be interesting to see just how shallow we could get it. -->>>

Doesn't work that way. The shallow DOF effect is coming from the lens being used, not from anything magical in the adapter. The adapter lets you use longer lenses. The lens delivers the shallow DOF.

If you want it really shallow, just use a longer lens. In 35mm photography you could get a 200, a 300, a 500, even a 1000mm lens (or more). With 1000mm, you could develop shallow DOF about a quarter of an inch deep (i.e., someone's pupils would be in focus, but their eyelashes out of focus).

Isaiah Kraus · February 7th, 2004, 05:09 PM

Hi all,

I've been working on a tripod mount point , and once the PC-7 dries I'll be able use a tripod. joy!

As to the gate size, I'm not sure if this is the info you want, but I measured the size of the (circular) projection on the CD from the 50mm and it turned out to be just about 1.75 inches in diameter. I've been zooming into this projection just enough to get past the vignetting on the edges. With a little help from photoshop, I figured the largest 4:3 rectangle one can fit in the center of my projection circle is 1.463 by 0.973 inches (just about the size of a 35mm exposure:). So, I estimate this size, maybe minus a little because I'm zooming past the vignetting/fall-off on the edges, is about the size of the area I'm recording.

The chroma banding, I agree is probably due to the cheap macro. Also possible that the CD was wobbling/I was moving the camera to fast. The CD has gyroscopic tendancy to stay oriented straight ahead -in a fast pan you can feel it pull against the direction you move in, so during the pan the CD pulls itself slightly out of alignment with the lens and camera. You can feel it sort of "catch up" with its new orientation at the end of the pan. Slow, gentle pans do not suffer from this problem. When I shoot more, I will try and find out if it only comes out in really bright/high contrast situations. I can't seem to duplicate it by just messing around in my house/basement, but its pretty dark inside.

I'm no carpenter, and I built this thing with a dremel, a portable drill, and a jigsaw so nothing is exact. Fortunately, though, once you get everything aligned properly, you can lock all the moving pieces down and not worry about the rig re-adjusting itself while you shoot. I built it by using the camera LCD as a guide -by centering the circular CD-projection in the LCD, getting focused and macro in place- and measuring approximate positions and distances. Then I built the bottom piece around those measurements.

Bob, I zoomed out all the way with the macro on, and I could just barely see the a speck of black in each corner -the ring around the macro lens, I presume- but the specks seemed pretty close to even in all four corners maybe a hair bigger on the left side, but almost imperceptable, really.

Yeah, the tripod mount point is offset to the right (if looked at from the back of the camera). It was a pain to get the proper hole position on the bottom piece for it. I also worry a bit that it "pinches" the camera's right side, and lifts up the left side when snugged down (I don't actually see the left side lifting up, I just fret over it). Oh well, I'm sure Canon's engineers knew what they were doing. I bought grippy/soft pads to cushion the mount area because of this.

Bob Hart · February 7th, 2004, 09:36 PM

Isiah. Please forgive my previous misidentification.

From your description it seems like the Canon is centred and my speculations are irrelevent.

As you mention with the CD and gyro effect, I found mine going off focus and snapping back in fast pans or tilts and had to make a firmer motor mount which brough back the CD not running true and softening the image a little.

Achromatic dioptre!! - I had read the posts. - Momentary lack of attention I guess.

Now to a general enquiry - a dumb question. Is a telescope eyepiece an achromatic dioptre?? It is made up of three pieces of glass, one as a single lens and two fused together to make a compound element about 3/8" thick. It goes softer and darker on the edges just before the vignette hits the corners when zooming back. If it was a wider diameter this would not be a problem but I have so far not found a wider one.

It does not seem to rainbow on sharp contrasts like the 7x worth of stacked close-up lenses do.

Brett Erskine · February 8th, 2004, 03:02 AM

Great information Isaiah. If you want to stick to a spinning CD design heres one way to make the cd always spin true. Have the very outer edge of your cd being held in place by running inside the groove of a small ball bearing.

Isaiah, Bob and Taylor- Hoya makes a 55mm +10 screw on achromat macro for $67. I hear that they just came out with their largest size, 58mm. RMPP for links and info.

Bob- I havent looked at telescope optics because they are too small. Use the marco above.

Brett Erskine
Director of Photography
Premiere Visions
1761 W. La Palma Ave., Suite #302
Anaheim, CA 92801
www.CinematographerReels.com
BErskine@CinematographerReels.com

Bob Hart · February 8th, 2004, 04:34 AM

Brett. Thanks for the Hoya info. I scoured internet references a few weeks ago but did not find it then.

Has anyone messed with mirrors in front of the Agus35 lens at all. Just for hell of it, I held a couple of auto mirrors in a 90-degree "vee" arrangement at a steep angle in front of the lens and an upright image into the camcorder can be had, albeit heavily cropped because the mirrors weren't big enough. The camcorder-Agus assembly had to be tilted down severely forward at about the angle of the movietube arrangement for a normal forward view.

The idea of a dirty big black box full of mirrors (no smoke) hanging off the front of the
Agus doesn't seem attractive but there might be a means in this method if people are going to put filter boxes on rods in front anyway.

Isaiah Kraus · February 8th, 2004, 12:49 PM

Yeah, Brett, I thought about that outer-edge sleeve idea. Maybe I could use a little pieces of teflon/plastic skid with slots cut into them for the CD edge to run in, as well. The problem is that, since the CD itself isn't true, these guides would probably just pop the CD off of the cd-motor mount in the center. A Solution to this is to glue the CD to the cd-motor mount, but I'm not ready to do that with this scratched, plastic CD GG (that I might trade in for glass or something later). I wouldnt want to have to break/chip it off the cd-motor mount later (probably destroy the mount/motor).Thanks for the info and suggestions.

Brett Erskine · February 8th, 2004, 01:20 PM

Bob here you go-

Hoya +10 achromat macros come in 55mm, 52mm, and 49mm sizes and sell for about $67 here:

http://www.2filter.com/hoya/hoyacloseup07.html

heres some info on them

http://www.camerastore.com/cat_003_hoya/003macro.html

I hear they just came out with a 58mm. Im ordering two today.

Bob Hart · February 8th, 2004, 11:46 PM

Thank you Brett. I've been playing around with binocular prism pairs for inverting image. They work but so far no useful luck. The prisms have to be too big to relay even the academy frame size to the CD and cannot fit within the lens flange to focal plane distance of the Nikon SLR lens and likely others for that matter. Unequal sized prisms might do it but then may be custom order territory = cost. With my close-coupled setup there is no room between the camcorder and CD for a prism path. The Hoya lens if it becomes available may make the option of a prism path between the CD and camcorder possible though they might have to be very large, again custom territory. A mirror array might have to suffice. Whatever erecting path is chosen it would also shorten the distance between CD and camcorder which was a disadvantage of the 7x stacked lenses which had to sit 5.5" off.

Brett Erskine · February 9th, 2004, 12:09 AM

Bob your an asset to this thread. Well I havent spent as much time on the prism idea because I planned on using a extra LCD for other reasons anyways but I with the limitations your mentioning it sound like two mirrors might be the better option. They are cheap and easily cut to any size...I think I might use that method so I'll save myself the trouble in post. ....Hmm better keep them real clean though otherwise we might see some out of focus 'dirt' in our shots. Thanks

Brett Erskine · February 9th, 2004, 12:47 AM

(10 minutes later...) Wait. I dont think two mirrors will beable to flip right side up AND mirror left to right. I think thats why you have at least one prism in a SLR viewing system. Please prove me wrong because I would love to just use mirrors for this.

February 7th, 2004, 10:32 AM	#918
Taylor Moore Regular Crew Join Date: Dec 2003 Location: Canada Posts: 94	Isaiah's Pix and Vids I am merely an observer a hoster...not creator. The great images are Isaiah's.....

February 7th, 2004, 01:12 PM	#920
Taylor Moore Regular Crew Join Date: Dec 2003 Location: Canada Posts: 94	Achromat macro Brett have you had any luck finding a good inexpensive "Achromat macro" for the DVX yet/ Centurys is just so damn expensive...

February 7th, 2004, 05:02 PM	#921
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	Re: Super crazy something <<<-- Originally posted by Seth Richter : Is it possible to use the formula agus35 to make two, for even more focal length? camera\|agus35\|agus35 I know that the light loss would be significant, but, it would be interesting to see just how shallow we could get it. -->>> Doesn't work that way. The shallow DOF effect is coming from the lens being used, not from anything magical in the adapter. The adapter lets you use longer lenses. The lens delivers the shallow DOF. If you want it really shallow, just use a longer lens. In 35mm photography you could get a 200, a 300, a 500, even a 1000mm lens (or more). With 1000mm, you could develop shallow DOF about a quarter of an inch deep (i.e., someone's pupils would be in focus, but their eyelashes out of focus).

February 7th, 2004, 05:44 AM	#916
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Taylor. Good looking pictures. The blue band off edge of the white shirt? Is that an effect normal to your camera in high contrast situations or instead maybe an off-axis prime lens on your Agus. The lens should be guaranteed square-on due to the construction method if this has been carefully done, so that leaves only the centering of the lens relative to the camcorder lens. Interestingly, the tripod base mount screw on the Canon camera in your construction image, appears that like the Sony PD150, it is offset to right relative to the camcorder lens centreline. I read somewhere that Canon make the PD150 lens sets. True or false I don't know. It would be interesting to know if the centre axis of the camcorder lens falls on the centre of the CCDs or slightly off-centre like the Sony. To find out, zoom back until you get a vignette from the close-up lens if it does this. If the vignette is offset in the viewfinder, then you might get a slightly better result if you re-align your Agus and camcorder for the centre of your projected image on the CD to be at the centre of your vignette before you zoom in, rather than at actual centre of your viewfinder image. This may help any smearing but might be at expense of having a stronger darker area down one side. This is all only just a maybe and possibly unhelpful speculation so ignore at will.

February 7th, 2004, 07:30 AM	#917
Filip Kovcin Major Player Join Date: Dec 2003 Location: warsaw, poland Posts: 440	Isaiah or taylor's pictures? as i understan these are Isaiah's pictures, and taylor is just kind to host it. right? filip

February 7th, 2004, 01:09 PM	#919
Brett Erskine Major Player Join Date: Dec 2003 Location: Anaheim, CA Posts: 445	Bob the problem he's having is due to chroma aberration. To solve it you need a (....alright everyone say it with me again)...ACHROMAT macro! Alright thats it! ;-) For the sake of my sanity Im not repeating myself again and again anymore. From now on "RMPP" stands for Read My Previous Post.

February 7th, 2004, 05:09 PM	#922
Isaiah Kraus New Boot Join Date: May 2003 Location: Columbus, Ohio Posts: 7	Hi all, I've been working on a tripod mount point , and once the PC-7 dries I'll be able use a tripod. joy! As to the gate size, I'm not sure if this is the info you want, but I measured the size of the (circular) projection on the CD from the 50mm and it turned out to be just about 1.75 inches in diameter. I've been zooming into this projection just enough to get past the vignetting on the edges. With a little help from photoshop, I figured the largest 4:3 rectangle one can fit in the center of my projection circle is 1.463 by 0.973 inches (just about the size of a 35mm exposure:). So, I estimate this size, maybe minus a little because I'm zooming past the vignetting/fall-off on the edges, is about the size of the area I'm recording. The chroma banding, I agree is probably due to the cheap macro. Also possible that the CD was wobbling/I was moving the camera to fast. The CD has gyroscopic tendancy to stay oriented straight ahead -in a fast pan you can feel it pull against the direction you move in, so during the pan the CD pulls itself slightly out of alignment with the lens and camera. You can feel it sort of "catch up" with its new orientation at the end of the pan. Slow, gentle pans do not suffer from this problem. When I shoot more, I will try and find out if it only comes out in really bright/high contrast situations. I can't seem to duplicate it by just messing around in my house/basement, but its pretty dark inside. I'm no carpenter, and I built this thing with a dremel, a portable drill, and a jigsaw so nothing is exact. Fortunately, though, once you get everything aligned properly, you can lock all the moving pieces down and not worry about the rig re-adjusting itself while you shoot. I built it by using the camera LCD as a guide -by centering the circular CD-projection in the LCD, getting focused and macro in place- and measuring approximate positions and distances. Then I built the bottom piece around those measurements. Bob, I zoomed out all the way with the macro on, and I could just barely see the a speck of black in each corner -the ring around the macro lens, I presume- but the specks seemed pretty close to even in all four corners maybe a hair bigger on the left side, but almost imperceptable, really. Yeah, the tripod mount point is offset to the right (if looked at from the back of the camera). It was a pain to get the proper hole position on the bottom piece for it. I also worry a bit that it "pinches" the camera's right side, and lifts up the left side when snugged down (I don't actually see the left side lifting up, I just fret over it). Oh well, I'm sure Canon's engineers knew what they were doing. I bought grippy/soft pads to cushion the mount area because of this.

February 7th, 2004, 09:36 PM	#923
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Isiah. Please forgive my previous misidentification. From your description it seems like the Canon is centred and my speculations are irrelevent. As you mention with the CD and gyro effect, I found mine going off focus and snapping back in fast pans or tilts and had to make a firmer motor mount which brough back the CD not running true and softening the image a little. Achromatic dioptre!! - I had read the posts. - Momentary lack of attention I guess. Now to a general enquiry - a dumb question. Is a telescope eyepiece an achromatic dioptre?? It is made up of three pieces of glass, one as a single lens and two fused together to make a compound element about 3/8" thick. It goes softer and darker on the edges just before the vignette hits the corners when zooming back. If it was a wider diameter this would not be a problem but I have so far not found a wider one. It does not seem to rainbow on sharp contrasts like the 7x worth of stacked close-up lenses do.

February 8th, 2004, 03:02 AM	#924
Brett Erskine Major Player Join Date: Dec 2003 Location: Anaheim, CA Posts: 445	Great information Isaiah. If you want to stick to a spinning CD design heres one way to make the cd always spin true. Have the very outer edge of your cd being held in place by running inside the groove of a small ball bearing. Isaiah, Bob and Taylor- Hoya makes a 55mm +10 screw on achromat macro for $67. I hear that they just came out with their largest size, 58mm. RMPP for links and info. Bob- I havent looked at telescope optics because they are too small. Use the marco above. Brett Erskine Director of Photography Premiere Visions 1761 W. La Palma Ave., Suite #302 Anaheim, CA 92801 www.CinematographerReels.com BErskine@CinematographerReels.com

February 8th, 2004, 04:34 AM	#925
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Brett. Thanks for the Hoya info. I scoured internet references a few weeks ago but did not find it then. Has anyone messed with mirrors in front of the Agus35 lens at all. Just for hell of it, I held a couple of auto mirrors in a 90-degree "vee" arrangement at a steep angle in front of the lens and an upright image into the camcorder can be had, albeit heavily cropped because the mirrors weren't big enough. The camcorder-Agus assembly had to be tilted down severely forward at about the angle of the movietube arrangement for a normal forward view. The idea of a dirty big black box full of mirrors (no smoke) hanging off the front of the Agus doesn't seem attractive but there might be a means in this method if people are going to put filter boxes on rods in front anyway.

February 8th, 2004, 12:49 PM	#926
Isaiah Kraus New Boot Join Date: May 2003 Location: Columbus, Ohio Posts: 7	Yeah, Brett, I thought about that outer-edge sleeve idea. Maybe I could use a little pieces of teflon/plastic skid with slots cut into them for the CD edge to run in, as well. The problem is that, since the CD itself isn't true, these guides would probably just pop the CD off of the cd-motor mount in the center. A Solution to this is to glue the CD to the cd-motor mount, but I'm not ready to do that with this scratched, plastic CD GG (that I might trade in for glass or something later). I wouldnt want to have to break/chip it off the cd-motor mount later (probably destroy the mount/motor).Thanks for the info and suggestions.

February 8th, 2004, 01:20 PM	#927
Brett Erskine Major Player Join Date: Dec 2003 Location: Anaheim, CA Posts: 445	Bob here you go- Hoya +10 achromat macros come in 55mm, 52mm, and 49mm sizes and sell for about $67 here: http://www.2filter.com/hoya/hoyacloseup07.html heres some info on them http://www.camerastore.com/cat_003_hoya/003macro.html I hear they just came out with a 58mm. Im ordering two today.

February 8th, 2004, 11:46 PM	#928
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Thank you Brett. I've been playing around with binocular prism pairs for inverting image. They work but so far no useful luck. The prisms have to be too big to relay even the academy frame size to the CD and cannot fit within the lens flange to focal plane distance of the Nikon SLR lens and likely others for that matter. Unequal sized prisms might do it but then may be custom order territory = cost. With my close-coupled setup there is no room between the camcorder and CD for a prism path. The Hoya lens if it becomes available may make the option of a prism path between the CD and camcorder possible though they might have to be very large, again custom territory. A mirror array might have to suffice. Whatever erecting path is chosen it would also shorten the distance between CD and camcorder which was a disadvantage of the 7x stacked lenses which had to sit 5.5" off.

February 9th, 2004, 12:09 AM	#929
Brett Erskine Major Player Join Date: Dec 2003 Location: Anaheim, CA Posts: 445	Bob your an asset to this thread. Well I havent spent as much time on the prism idea because I planned on using a extra LCD for other reasons anyways but I with the limitations your mentioning it sound like two mirrors might be the better option. They are cheap and easily cut to any size...I think I might use that method so I'll save myself the trouble in post. ....Hmm better keep them real clean though otherwise we might see some out of focus 'dirt' in our shots. Thanks

February 9th, 2004, 12:47 AM	#930
Brett Erskine Major Player Join Date: Dec 2003 Location: Anaheim, CA Posts: 445	(10 minutes later...) Wait. I dont think two mirrors will beable to flip right side up AND mirror left to right. I think thats why you have at least one prism in a SLR viewing system. Please prove me wrong because I would love to just use mirrors for this.