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Old January 21st, 2004, 08:49 PM   #826
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Im wondering how many people are working on this? I mean we are on page 55 with 824 replies!!! but...

It's kinda funny how we havent moved that far or at all from Agus's first version. The first footage he posted is still fresh in my mind...the smoke rolling off the cigarette then tumbling off into the background fading away, Great clip Agus.

I post this because I would like to see everyone start thinking about alternatives to the "plastic rotating GG" which is inherently flawed because its plastic, look towards other options and technolgies. Im currently trying to get a real glass CD from a CD reproducing facility so thats what im working on right now.

Im going to start a list of tasks and goals to complete, with everyones help we can tackle this!

ok, here we go

1- find a replacement for the plastic GG that is not too expensive (glass, crystal, 35mm camera GG parts?)

2- resolve the Vigneting/hot spot issue (fresnel about works 80%?)


...only 2 goals for now, If you want to add to this just let me know. I will update this every couple of days.

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Old January 22nd, 2004, 03:03 AM   #827
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I've been thinking the same way for awhile. This project has been on my mind a long time before this thread was started and since I just recently found out that other people are trying to make adapters too the design I had been working on has been evolving - seperate from outside input and ideas.

First of alot of the ideas of this thread are starting to point of the way I designed my adapter. But there are some improvements that are being over looked.

1)You'll need a APOCHROMATIC triplet lens in order to properly focus on the "ground glass".

2)There are better than the CD plastic people. Research other materials and learn the characteristics of light and how it reacts to diffusion to figure out the best solution.

3)A fresnel can be replaced by a simple lens. With greater clarity.

4)Argus' design served the purpose of a $20 solution. Think bigger.

5)Panavision anamorphic lens can be used on your adaper to increase the horizontal resolution of your video to near HD standards.

6)Prisms arent needed if you plan on using a seperate small on board LCD screen that can electronically flip and mirror image your video.

7)The same monitor may be able to unsqueeze your anamorphic image so you can preview what your shooting properly as you shoot it.

8)Dont rotate a CD of ground glass. You need to make it more in a overall circular motion. Mini35 newest model changed to work this way.

I can keep on going on and on and everything Im telling you here I had to learn or figured out for myself by doing research. Im just saying that we could be doing alot more here. Its long time over due that we greatly evolve the original $20 design.
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Old January 22nd, 2004, 03:40 AM   #828
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John.

I have sent a request to Hiro at Ohara in Japan for a per unit quote on CD sized optical disks with hole in centre for making groundglasses. We have arrived at a glass type which is one of the cheaper lines they have.

He will be sending me a small sample for me to try to put the groundglass finish on. Different glasses have different hardnesses and the aluminium oxide which apparently yields the best result may not be hard enough to dress a harder glass.

Once this is sorted and some prices quoted we may well have a source for real groundglass disks. The post a few back from a chemist offers some encouragement in possibly being able to produce a better groundglass by chemical etching.

I have an anamorphic adaptor mount prototyped and working for the Century Optics 16:9 - Micro Nikkor 55mm SLR lens combination. For this I attempted to construct a how-to for posting as it has applications for other than the AGUS35, but the document ended up being 6mb including .bmp illustrations, and the word processor has saved it but won't re-open it. I might still send the 5 page .pdf text-only I saved and the separate .jpg images to Chris for posting here. It's made out of plumbers plastic bits but is intended as a proving pattern for a metal adaptor to be made later.

Regarding the hot spot, if you frame not to the 35mm SLR still-camera gate, but to the smaller 35mm widescreen-movie gate on the groundglass image, (21mm x 11mm approx), stay on f5.6 or wider with the SLR lens, the hot spot mostly goes away except for wideangle lenses like 28mm.

I haven't used a fresnel lens and haven't discovered a need to so far.
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Old January 22nd, 2004, 04:44 AM   #829
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Bob,

I really dont think that the PS dudes really give a damn about this project.

Maybe tomorrow i will start experimenting with prism to rotate the image. Also...i found something really really cool about prism and mirrors, and that is that you almost dont need a fresnel lens, you can full zoom in, and the camera dont need to enter to macro mode...

Make the test just to be sure, and put your dv camera behind your slr camera viefinder and try to zoom in until there is no vigenting and tell me what happens.


Also,Even if we havent flip up the image we are getting some amazing footage.

I will post it really soon, as we are still shooting this short film, which was the reason the adapter was built.

Thanks for all the support

Agus Casse
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Old January 22nd, 2004, 12:28 PM   #830
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Agus.

Into the Nikon FM2 viewfinder with the PD150, you get an upright sharp image similar to the fixed groundglass tests I have done. By the time you zoom through to eliminate the vignetting your image area on the SLR groundglass is a little smaller than the size of the 35mm widescreen movie frame. The centre circle on the groundglass fills the camcorder frame.

This is the same issue which sent me for the telescope eyepiece lens when adapting the night vision. - Eliminating the vignette causes over-magnification of the centre of the available image through the standard eyepiece because the exit pupil is too small for the camcorder. When zooming through to eliminate the vignette, the image grows faster behind the retreating vignette outline.

Smaller camcorders may not have this problem as much as a PD150 or XL1.

Maybe a larger prism and eyepiece lens with wider exit pupil would deal with the vignette problem and centre over-enlargement. I know absolutely nothing about prisms so I am of no use on this subject.

The resolution from the current Agus35's is as sharp and sometimes sharper than stills I've seen posted from the Mini35 into MiniDV. This may be because there are fewer pieces of glass between the camcorder and groundglass.
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Old January 22nd, 2004, 02:52 PM   #831
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Brett,

I think your gruff insistence that we all need to do some research is a bit off, especially when your post plays like someone who thinks they know it all, and yet refuses to share their findings. Mark that as the first offense of your post -- completely at odds with the spirit of the original design...

Then you go on to say such incoherent things as:

"2)There are better than the CD plastic people. Research other materials..."

Apparently you've overlooked pages upon pages of research in this thread and others where people have done just that.

If you've got advice on where we can find a better solution than a plastic CD that is: a) affordable and readily accessible for all here, b) rugged and/or disposable enough as to be field-worthy material, then by all means you've got my attention.

"3)A fresnel can be replaced by a simple lens. With greater clarity."

Yes. Thanks. We've been through this too.

"5)Panavision anamorphic lens can be used on your adaper to increase the horizontal resolution of your video to near HD standards."

CCD dictates resolution, not lens dynamics. Are you talking about aspect ratio?

And...if you've got access to Panavision lenses, why are you wasting your time with a project that aims to undercut a $7,500 device by building a $30-400 one? I presume you're wealthy enough to go out and get yourself a genuine P&S device...again, contrary to the spirit of the project in the first place (noticing a pattern yet?)

...

Maybe when you come back with more information that tempers what appears to be little more than hubris, we'll take your word for it.

Until then, Agus's footage looks good enough that I don't feel the need to "think bigger."

- jim
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Old January 22nd, 2004, 03:27 PM   #832
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Has anybody yet tried disassembling their camcorder flip-out screen to rotate the LCD screen 180 degrees within its frame?
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Old January 22nd, 2004, 05:39 PM   #833
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Jim I like to start by apologizing for my moment of frustration in my last post. Let me better explain myself. I was reacting to John's comment that after 55 pages and 824 replies we haven't moved too far from the original design. In that moment of shared frustration on how long we have all been working on this versus how much we have progressed I had to agree with him but only to a point. While some people are still tinkering with the original design their are others on this thread that have taken the time to truely understand the chracteristics of optics and how it applies in theory to what we are trying to do here. These are the people that have progressed the adapter to where it is now. I was hoping with my original post that we could ALL get on the same page and move as a group even faster on this project. But while I had good intentions I had the wrong approach so once again I apologize for that.

Anyways as far as more details on the parts I described:

1)APOchromatic triplets lenses (see above post)

2)Ground Glass- as we all know ground glass comes in different grades of texture. Each has their own image projectable characteristics. There is a trade off between image brightness and how much grain is in the glass. There is a point where the grain is so fine that too much of the images' light goes right through the glass and the image starts to appear dark again. Also the hot spot many people are seeing is due to one or a combination of two things. Either they arent using a fresnel/lens to redirect the 35mm lens light STRAIGHT at the ground glass or they are using ground glass of the wrong grain texture. In general the grainer the glass the more is likely to pick up incoming light from more extreme angles (ie wide angle lenses). But even though the ground glass may be moving the camera will still pick up the diffused glowing characteristic in the image so you cant just uses very grainy glass. Acid etching is a old photo glass process and is very promising as it creates a finer texture to the glass. And then you have Bosscreen's out there with no grain because instead of texture glass they use a thin wax solution sandwiched between two pieces of glass. Considering they are 4x5 in size, cant be cut to a smaller size or have a cd hole drilled in the middle and the its possible the wax will melt on hot days (not to mention we would be spinning it at high speed) you can probably guess what will happen. Edmund Scientifc offer something called Halo Diffusers which is currently being research for its grainless properties. And with the grainless glass offered in the MovieTube adapter we now know there is at least one perfect solution out there waiting to be found. Until then its the missing link to the sucess of our adapters.

3)fresnel lens are used with ground glass for the reason above. But for optical systems like were are making we need a more seemless lens then the grooves found in the fresel. There is a reason why camera lenses dont use fresnels. There are however used in SLR viewfinders because they save space, but they trade it in for optical quality.

4)Argus made that first design to mainly prove a point. To prove that it could be done for $20 and with household items but in order to do this with professional results we are going to have incorporate professional optics, parts and materials. So this means its going to cost more but if we are clever about it I dont see it getting over a few hundred dollars to do it right.

5)anamorphic lenses with a 2.35 aspect ratio squeeze the image to fit on a more square like target gate area. When you use these lens with your dv camera your squeezing that projecting image on to you FULL CCD. While if you simply shoot with the cameras letterbox feature your throwing away 1/3 and in this case 1/2 of your cameras possible resolution. BTW you dont have to rent expensive panavision anamorphics to do this. On the low end you can BUY cheap Russian made 35mm anamorphic lenses for next to nothing. They pop up on Ebay often.

6)Prisms vs. LCD screens (see above post)

7)Anamorphic Unsqueeze in LCD (see number 5)

8)The latest version of the P+S Technik Mini35 abandoned the idea of spinning the ground glass disc due to image quality problems and the overall adaper size was too big to accomodate it. Instead they choose to vibrate it in one place a circular motion similar a disc sander. IF we end up not finding "THE grainless glass" and have to move it in some way this is probably are best option. I have a design if anyones interested.

Hope that answers your questions.
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Old January 23rd, 2004, 12:55 AM   #835
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Looks great Agus!
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Old January 23rd, 2004, 04:45 AM   #836
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ground glass

I am still working on making ground glass. the first try was with
powder from the glass shop. results were ok . the second try was with glass etching cream. this worked much better the glass shop cut the glass in the shape of a cd . put on the etching cream for about an hour .this was purchased at pearl art supply store the name was -{armour etch} I did not seat the cd on the motor true and I am getting vibration. the glass shop charged
me $12 to cut 4 glass cds and I think the etching cream was about $7 .... thanks again to everyone for all the great research
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Old January 23rd, 2004, 04:54 AM   #837
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Robert.

The causing of the entrails of my camera to see the light of day strikes abject fear into my heart lest I break something in the attempt.

There may be merit in your idea however. It may be that the display can be rewired for switchable inverted operation. The switching function which occurs when the LCD screens are faced forward may be as simple as contact points or brushes in a swivel base. I don't know the electronic magic but if the reversal occurs by this method, then causing this by an added small switch might be possible.

I shall have to study that website with the dismantled VX2000 again.
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Old January 23rd, 2004, 08:14 AM   #838
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Movie Tube

Got this today, thought you all would appreciate it:

"Hello Seth Richter:
Thanks for your interest in our 35mm Camera system called MOVIEtube.
MOVIEtube will hit the market summer 2004 and will be sold in various kinds.
The MOVIEtube product line is providing the same depth of field and angel of view as the 35mm format.
Because there is no need to rotate the grain less groundglas, MOVIEtube is providing a sharper image with no hotspot and it is operating without any noise. The patented groundglas provides a almost loss less light transmission- for shooting in artificial light situations and by night.
For use in professional productions we developed the MOVIEtube PRO, with professional features known from traditional movie cameras:

- A integrated shoulder-set for use on shoulder for living-camera
moves
- Three WALTERgrip handles for low shots and handheld action
- A socket for use with Sony compatible professional viewfinder,
to provide a sharp image for controlling the focus.
- Equipped with standard Arri connectors for wireless
follow-focus, wireless image transmitter and all the other Arri
accessories like focus control monitor etc.
- Standard video rods for video accessories
- 35mm or 16mm rods for connecting matboxes and accessories
- 2 Balanced XLR-connectors for connecting professional sound
gear

To start more cost-conscious with the MOVIEtube product line we are proud to introduce the MOVIEtube LT.
The MOVIEtube LT is a small unit with less features than the MOVIEtube PRO, but providing the same Image as the PRO.
The MOVIEtube LT is running without electronic power, except the Battery on the DV-Camera. Therefore it is lightweight, small and by the fraction of the cost of a MOVIEtube PRO. MOVIEtube LT can be later upgraded to be a full-blown MOVIEtube PRO unit.

The MOVIEtube System accepts Lenses from Panavision, Arri, Nikon, Canon, Minolta, Pentax, Contax!

At the moment the MOVIEtube 35mm Camera System is approved for the following cameras:*

- Sony PD-100
- Sony PD-150
- Sony VX 1000/2000
- Sony TVR Series
- Canon XM2
- Panasonic DVX100
- others will follow!

* Approved cameras can be docked directly on the MOVIEtube. No additional relay lenses are needed. Canon XL-1 /s is not supported.

At the moment we are not able to quote the exact price for the MOVIEtube PRO and the MOVIEtube LT .

For further information please visit frequently our Web Domain http://www.movietube.com it will be online in a few months! A 3D technique section will provide answers for many questions about MOVIEtube. A show room and a user forum are waiting to be visited.

Thanks again for your interest!

We are receiving huge interest in MOVIEtube from people all around the globe, even though we didnít start the MOVIEtube sales promotion yet!We would be happy to welcome you as a satisfied MOVIEtube user some day

Best Regards
JK
-Marketing & Sales MOVIEtube-"
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Old January 23rd, 2004, 09:04 AM   #839
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movie tube

The movietube web site seems to indicate that they're able to do all this without spinning or vibrating the ground glass. The use of microcrystalline lens.

I think if we find out how this material is made, or find a similar material, I think we're home. the work being done on the {static adapter thread }looks to be going in that direction.
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Old January 23rd, 2004, 09:21 AM   #840
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Brett,

I appreciate your apologies -- it's rare to find someone online who holds themselves accountable for their words and actions, and fewer still who would ever admit that they could be wrong.

However, I think you've got different ideas about the Agus35 than I, and so while I can understand and respect what you're trying to do by "advancing" the design, it runs contrary to what I hold as being most valuable.

More clearly, I mean to say that my Agus35 design works from a position of assumed ignorance and poverty -- I don't have the knowledge of optics, the time to obtain such knowledge, and even less, the money to pursue your goals.

I'm a working filmmaker, which puts me in a position to assume that these "deficiencies" are true of others like me, and so accessibility and simplicity are my two main design priorities.

As an extension of this, I'd suggest that the further you stray from these two guidelines, it's more and more appropriate to say you're endeavoring an entirely different project -- it's the difference between ordering a cheesesteak sandwich and a filet mignon -- both have their ups and downs, and both share certain commonalities, but it would be foolish to argue they're "the same thing."

Good luck, though, and I'm looking forward to your findings.

- jim
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