As far as still camera bodies are concerned as I remember there are third party lens adapters out there already for anyone who wants to fit say a Minolta on a Nikon or perhaps a Nikon on a Canon (etc..). Personally Im into this project not only for the DOF but I plan on using PL mount anamorphic lens so I can double my vertical resolution of my footage. So I'm going to have a PL mount on my adapter. Not to mention they have PL to Nikon mount adapter rings out there so you get the best of both worlds. More expensive for sure but the mini35 becomes twice as useful.

Anyways back to the first heardle - the achromat macro/diopter type lens. This has been real hard to find. There are equations at www.dvxuser.com on how to determine the power of the diopter thats going to work for you but nothing beats trial and error. I own a DVX. This is one of the hardest cameras to find a diopter for because of both its lens diameter and poor minimum focus distance (dvx100a model does a better job). I've determined I need at least a +16/5x power achromat to see the target area size of 24mm x 18mm. I have only seen this spec in optics for high end loupes, hand held aspheric magnifing lens and microscope lenses. Obviously the microscope lenses are too small to shoot through but perhaps these achromat loupes lor a large magnifing lenses like these might do the trick:

http://www.edmundoptics.com/IOD/Disp...productid=1784

http://www.bhphotovideo.com/bnh/cont...&is=REG&BI=155

http://cgi.ebay.com/ws/eBayISAPI.dll...category=30030

http://cgi.ebay.com/ws/eBayISAPI.dll...category=16508

http://www.eschenbach.com/catalog/subfamily.asp?18

Now these are all smaller in diameter then 72mm but, to a point, that shouldnt matter because we're most likely zooming in just a little anyways. Hope these help.

Everyone interested in having a static adapter - YES!!
 

Todd,

I think an official prototype is a great idea...it would be great if they can keep it as simple as it is and compatible with 52-58-72mm(for dvx100) lens threads..or i guess using a step up ring would work for everyone...The point is keeping it simple and cheap...logically i think the best would be just to produce the macro,ground glass combination with the slr lens mount on single adapter so everyone can use their own choice of lenses...hopefully they won't exaggerate the price of this simple and great idea.

Thanks to everyone

nikon adapter?
 

Is there such a thing as a f-mount to Canon FD mount adapter?

I piddled around on ebay and found a few other adapters to and from canon FD's, but didn't notice a nikon to canon one.

Jeremiah

Since the general consensus is toward hand-grinding lenses, I've got a few questions fo those of you financially equipped to take the leap into purchasing aluminum-oxide and your other components:

What grade of aluminum-oxide is the minimum needed to successfully create a GG? #500?

As a subset of this question -- what grade is optimal?

I've taken note of the link to sub-micron aluminum-oxide (which is $23.20 a pound, BTW) but I'm wondering if this is, in fact, a superior solution. In other words -- would it be possible to create too fine a grain?

Is the goal to create gaps between grains that are just wide enough to allow light to pass through, but at the same time, create fine enough grains so as to never pick them up on the CCD? What's the balance between these two, if any?

Or is the desire just to create a uniform frost of a particular opacity, with grains merely small enough to not be seen -- and all else is fair game?

- jim

I can tell you that any light passing straight thru the glass without hitting the "frosted/grain" would be wasted as it wouldnt help produce the projected image. As far as the shape fine grain - past it needing to be smaller than what the camera's CCD can pick up - Im not sure what texture would work best. It would be fair to say some textures would scatter the light differently then others. For example some would add more of a unwanted diffused look to the image while others may be very effecient and diffuse the image only as much as it needs to to create a image on the groung glass. These effecient textures would most likely produce a image that can only best be viewable straight on because most of the light isnt being scattered too much and wasted. In the end its a interesting point that probably can only be answered by a optical designer.

Aldu 35
 

The adapter Made in China ???

Here is my final adapter.

http://ideaspora.net/aldu35/ALDU35.JPG

Alain Dumais

Alain --

Man, that sucker's huge.

- jim

okay, if that's the final adapter, then we should have enough to move ahead with specifications to send to the manufacturing company. Does anyone have any specific instructions together?

Alain,

Can you post some clips with the new adapter if you have time...

Thanks

Off the subject a little, the look of Alains adaptor makes me wanna get some barn doors too for the complete pro look! :-)

Nice work Alain!

Hey Alain what EXACTLY are you using for your macro lens?

Hoya sells +10 two element achromat macro filters. They are the single strongest photo marketed screw on macro lens I've ever found and they are chroma aberration free.

They 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

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

Brett,
Do you think one of the Hoya lens could be used with the DVX and a stepup ring?

aldu 35
 

alain it looks great. I am waiting for the order of aluminum oxide
I can't wait to start work on the aldu35 your hard work with the ground glass was the breakthrough .I remember the clip of the hand painted pottery. this device will help the small filmmaker
create a artistic look that was beyond our means. this is truly
a device for the people. thank you for all your hard work

As far as whether or not the above Hoya macro lens will work on the DVX with a step down ring - the short answer is you wont know for sure without trying it. I have a DVX and I plan on doing the following to get a better idea if it will work before I buy:

1)A quick referance could be made by grabing anything that measures just under 55mm such as a ruler or another type of filter and hold it in front of the DVX's lens. See if you can zoom thru the filter (or past the 55mm markings in the case of the ruler)

2)For the DVX you'll need a macro lens like the Hoya but more than one stacked on top of each other to make it a total of at least a +13 diopter rating. And if you plan on using 35mm MOTION PICTURE lenses you'll need it all to add up to a +16 or greater. The second macro lens doesnt have to be a +10. Hoya and alot of other companies make +3, +7, etc. But its absolutely necessary that they both are two element achromats.

3)Remember that between the step down ring(s) and the two somewhat thicker Hoya filters stacked on top of each other - it will add a bit more length to the system in front of the lens so you might have to zoom in just a bit more than if you simply had one lens on.

The simple fact that this will add about a $100 to the project is sure to deter some people but for thoughs looking at this adapter as a professional solution and are unwilling to sacrifice a noticeable amount of image sharpness for 35mm DOF the investment is well worth it.

Thanx Brett and Alain
 

I really appreciate your homework and truely would like to have the option of both SLR lens and Arri or PL lens options. Looking forward to your test results.

Bret (and others): I am working on one of these devices for my Canon GL2. My aluminum oxide is expected to arrive today and my uv filter is waiting.

As far as I understand from reading these posts, I want to take the projected image from the ground glass and have it fill the entire frame of the camera, by enlarging the projected image via a separate magnifier and/or zooming in on the image.


For the GL2 in particular, with a 58mm filter thread, what would you recommend in the way of a diopter/achromat/magnifier?


Currently, all I have for my GL2 is the WD58h Wide Angle lens, which I don't think would be of any use for this project.

Any help from you guys would be really appreciated!


,Frank

Each camera's stock lens has different characteristics so you may or may not need such a powerful diopter. Trial and error is going to be the best way for you any anyone else that wants to find out what power diopter they need for their particular camera.

The easiest way to do it will be to go down to your local camera shop that has thoughs cheap single element diopters (often in a three pack of +1, +3, +5) and start stacking them until you can fill the frame with a square measuring 24mm by 18mm. When you find the perfect combination add up all the filter powers and thats the power that you'll need to find in a achromat (two element)diopter.

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

Heres another option for a macro lens. Its a double element thats aprox. +16.7 in power and the beauty is you only need one of these. The glass itself measures 40mm and woud need to be fitted into a aftermarket filter ring. You can find it here:

http://www.edmundoptics.com//IOD/Dis...productid=1749

Stock Number: NT45-218

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

Alain how is the hot spot issue with this static solution?

How are people resolving this issue?

Alain good progress!
Couple questions for Brett and Alain.
Brett how is the Chinese idea going?
Alain what is that lcd maximizer you are using? Does it help out a lot?
Seems like your adapter is the what i am going for in a way.

Brett: Thanks! If that one is the only piece I would need, then I'd be willing to spend that for it.

I appreciate your research and input!


,Frank

Dmitri take another look at the past post. I don't have anything to do with that idea. It would be nice if it ends up working out though.

On a side note we have a hell of alot more people reading versus contributing to this thread. More of us need to get involved and less of us should be just waiting in the shadows while everyone else does all the work for them. Want this project finished faster/better? I cant under rate the importance of getting involved. To everyone else great job!

I am looking for an adapter that will let me clip in my 50mm lens to my device, any ideas?

Thanks

Alain's got new (and improved!) footage up:

http://ideaspora.net/aldu35/newclip.wmv

(right-click, save-as)

- jim

My order of 120 and 240 grit Al. Ox. has arrived. I have to wait 4 weeks for 600 grit. Has anyone found 500 or 600 grit that is not on back order? Thanks

Todd:
I got my 600 grit from here:
http://www.sisweb.com/ms/sis/alumoxid.htm

Cost me under $15 for a 4oz bottle + shipping. Ordered it last week (Thursday) and it is in now.

Very friendly people on the phone. I recommend them.

,Frank

Found another place for aluminum oxide.

http://www.rocks4u.com/

It's a rock polishing company. I called them and have all sorts different grits of aluminum oxide. He even mentioned some sort of diamon dust stuff that they have up to like 100,000

Anyways they seemed pretty cheap and shipping is only going to be a couple of days.

<<<-- Originally posted by Frank Ladner : Todd:
I got my 600 grit from here:
http://www.sisweb.com/ms/sis/alumoxid.htm

Cost me under $15 for a 4oz bottle + shipping. Ordered it last week (Thursday) and it is in now.

Very friendly people on the phone. I recommend them.


,Frank -->>>

whats up with the extra $10 'handling fee'?, makes the total $25 plus s/h = $30+ , I wouldnt pay that out of sheer principle.

Dont forget the issue with the hot spot. Hot spots on the ground glass are due to both your cameras viewing angle and the angle at which the 35mm image is being projected at. The greater its off axis from the camera the worse the light fall off on the edges. And dont just zoom in past it. That a cheap way around that will make alot of other things worse (DOF, grain, FOV, exposure, etc.).

How do you fix it properly?

Just look at a SLR viewfinder for the answers. Right before the light hits the ground glass in a still camera's viewfinder it goes through a small lens thats job is to redirect the image coming from the 35mm lens and send all angles straight at the ground glass. Thats why their arent any hot spots in you still camera viewfinder. It also makes the whole system more light effecient. Alot of people dont seem to be including this lens in their design and choosing to just zoom past it all. For everyone the lens I talking about is called a condensor and come in two types (fresnel and a regular lens). I highly recommend that you dont choose the fresnel type because the ridges of its design will project themselves on your ground glass and will be viewable to your video camera.

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

John: Sorry, I forgot to mention. Since I called the order in, the guy said they wouldn't charge that handling fee. May sound wierd, but apparently they charge that for internet orders.

,Frank

Brett where do you get one of these regular condenser lenses and about what do they cost?

Brett: This makes sense, with the condenser being curved on one side and flat on the other. The curved side would pick up the image and project it out straight.

What would the correct condenser size be for the given filter size? ie. should it be equal to or larger than the filter?

Thanks for this suggestion!

,Frank

I'm just stopping in to see what people are thinking about the LCD monitor issue. I think the previous link had only one among all the options available that advertised its ability to "inverse" the image. This makes me skeptical about purchasing a lot of the models out there.

For instance, here are two I've found that would otherwise seem promising, but I don't know whether or not they can rotate and flip the image:

One.

Two.

Does anyone here have a sufficiently comprehensive understanding of electronics so as to share how you could jury-rig a monitor with an inverse and rotated image? Is it a matter of just swapping inputs?

- jim

As far as what, how much and where of condensor lenses just read my previous post again. All the answers are there.

For CRT's only I would have to say yes you can switch certain wires to flip the image but your likely to get a SERIOUS maybe even deadly shock for your troubles. Wouldnt help anyways. We need LCDs for this app. Like most of the questions just take the time to look at my previous post but I'll give you the link again anyways. These will do what you need:

http://www.portablemp3playerstore.com/

They are also on ebay all the time for cheap. Look for "sunvisor style" LCD screens.

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

Brett,

Thanks for your response, though in case you missed it, this link you provide is exactly what I've first linked above. To reiterate -- among all the models of LCD screens listed only one boasts of being capable of inversing an image.

I'm not about to shell out the dough to get a different (read: cheaper, smaller) model and risk it not having this feature.

- jim

I spent about 40 minutes grinding my uv filter on 600 grit aluminum oxide today and the results are excellent. I get a very fine grain glass that is uniform in brightness (no hot spots).

After testing it a bit on my GL2, I see that I badly need a condenser or some other solution. (The center of the image is very nice and sharp, though.)
So I have called around and have someone that is gonna bring me an old slr body tomorrow. If the condenser or something from that doesn't work, I guess I'll have to order a condenser, but I'll try and let you guys know what happens.

Thanks to all of you for posting your suggestions!

,Frank

Heres my "PremiereVisions35 adapter" (ha ha or whatever you would call it) design equation:

35mm lens>condensor lens>600+ alum. powder ground glass or better>macro lens (+16 power*)>video camera with on board image flipable LCD

(*for DVX100. May be different power for other cameras)

And if you want to have the image interially optically flip and mirror without the aid of a extra LCD the equation is:

35mm lens>condensor lens>600+ alum. powder ground glass or better>Pechan prism>roof pentaprism>macro lens (+16 power*)>video camera

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

My 35mm Minolta SLR didn't have a condenser lens unless it was built into one of the prisms or the ground glass. The Ground glass (plastic) actually looked more like a fresnal. It won't work though. So I need to find a condenser lens somewhere else.

Alain,

Just watched the lastest footage. Very nice. I can't get over the very shallow depth of field. In the shot with the guitar only 4 or 5 frets are in focus. Never thought I'd say this but, almost too shallow for many applications.

Was the aperture wide open? Any chance we could see some footage shot in bright lights or outdoors?

Paul
dvdof.com

Depth of field gets shallower the closer you are to the subject, I think.