35mm Adapter Static Aldu35

[Bob Hart]

Shooting upside-down with one's back (and fat backside when bending over to a low mounted viewfinder) towards the subject is quite workable after practice and getting used to operating the controls in the new position. The hardest part is the passing public and their questions.

The Agus/Aldu plus camcorder combination is a little more tricky to set up and maintain quality with under pressure of any live event, so a sound recordist or camera assistant is desirable.

[Ernest Acosta]

Obin can you post a picture of your adapter? Also how did you create your ground glass? Are you using aluminum oxide?

[Filip Kovcin]

<<<-- Originally posted by Obin Olson : does anyone have an easy way to flip the image BEFORE it hits the camera lens? I got this far...can't be too much harder can it? -->>>

i think you can find many different solutions in static solution thread

check this link

http://www.dvinfo.net/conf/showthread.php?s=&threadid=18690

and many different solutions are somehow mentioned also in aldu/adus thread or in discussion about upside down monitor solutions. take a closer look.
think about porro prisms or roof prism with amici prism. but then you are closer to the mini35 then to aldu due to physical limitation of those solutions (they are not in straight line like aldu)

filip

[John Cabrera]

Regarding the image flipping... this was mentioned once before in a post by someone... I've always found it interesting and wonder why it's not been mentioned more as a viable solution.

http://www.leadtools.com/SDK/Multimedia/Direct-Show-Filters/Multimedia-DirectShow-Rotate.htm

[Nicholi Brossia]

Due to the real-time effects in most editors now, many users have decided that flipping the image in-camera isn't very necessary or worth the extra time and money. That program does look handy, but will be soon outdated, if not already.

[John Cabrera]

Agreed that inc amera flipping isn't ideal for this kind of project. But capturing the footage flipped would at the very least save you time at final render. Now if there are as you say other tools that have or are about to surpass this piece of software in affordability and accessability, then the members of this forum need know about them. That's what we're here for. Till we know what else is out there all we can work with is the best of what we have.

John

[Bob Hart]

I called up the website but with my browser and slow landline (785bps to 5k), the computer started going in circles before it managed to download the page, so I didn't perservere.

[Pat Worrell]

This is my first post, first off, big props to aldu and alain for their contributions, simply incredible. Secondly, Ive built both versions, just finished my static and have a couple of pictures (short clip as well), who can I send these to for all to see?

Thanks

Pat

[Bob Hart]

There's a number of people here who might host images who may reply to your request. If you email Chris Hurd at :-

"chris@dvinfo.net"

with a request, he may set up an address here which might look like :-

"www.dvinfo.net/media/worrell" or similar. I have been posting my bits and pieces here through his favour by sending via email attachments.

My stuff is at an archive at :-

"www.dvinfo.net/media/hart". If viewed by date it might give you an idea of how the image quality evolves. Lately it has taken a step backwards as I have been experimenting with glass disks.

[Jonathon Wilson]

I built a platform which holds my spinning glass adapter and a mounting device which holds the camcorder up to the adapter upside down. I use an external monitor during recording, so I get image through the adapter on tape and on monitor while viewing which is optically correct. Works well.

[Rob Scott]

Back on page 56 of this thread, Damion Luaiye mentioned that if we got 50 orders, we might be able to get custom focus screens made.

Has there been any more news about this? I'd love to see some tests -- I'd even send someone a few bucks via PayPal to help pay for materials -- because if it looks good, I'd be interested in buying several of these.

Specifically, I'd like to see how it looks on a 720p HD camera like the one that Obin Olson is working on.

I'd love to build one of these adapters, but I have back and neck problems, so grinding a piece of glass for 2+ hours does not sound like fun. :-)

[Damion Luaiye]

The present hurdle: Beattie screens use fresnel lenses and the Beattie folks need a focal length spec (distance from eye to screen). With all of the distance variations and diopter configurations we have in our rigs I was unsure what length to give - any suggestions?

Meantime, today I mounted a Nikon type D, unmarked matte screen into a 55 mm ring. It's the only completely unmarked view screen I've been able to find - $22. The grain is finer than anything I've yet produced and is completely uniform, but the screen is a bit of a pain to mount and presumably will need frequent slight adjustment to maintain alignment.

A filter ring sized screen would be great. I haven't had a chance to try to test a full size Beattie screen in the hopes of determining the appropriate focal length - hopefully next week.

- Damion

[Bob Hart]

RE: DRESSING AND GRINDING DISKS.

I have been scheming and planning for means of cheaply automating the process. The machine is yet to be completed and the following is all unproven theory.

So far it looks like being a gemstone tumbler style thing :-

1 x washing machine AC pump motor.

1 x automotive engine water pump. - or -
1 x automotive power steer pump.

1 x oversize elastic band or flat drive belt.

1 x 50 disk CD-R case outer cover.

1 x 25 disk CD-R case outer cover.

1 x 25 disk CD-R case inner spindle. (Pillar cut off).

Several scrapped CD-R disks for spacers.

One custom brass donut shaped roller, with deep concentric grooves cut in it about 2mm (1/16") apart.

1 x door hinge.

3 x pieces of chipboard or scrap ply panel.

Assortment of screws gutter bolts etc..

METHOD:

Water pump or power steer pump is mounted by its bolt-holes to a wooden panel. A clearance hole may have to be cut out for the impeller.

The 50 disk CD-R outer is mounted to the pulley with bolts or screws. Use sealer or contact adhesive on the heads to lock them.

The washing machine pump motor is mounted to drive the water pump or power steer pump with a flat belt straight off the motor shaft like a flat belt turntable. (The plastic pump housing, seal and impeller will have to be removed. The plastic seal retainer may be an integral part of the motor and have to be retained for mounting purposes.)

The timber panel is mounted to a base plate with the door hinge. The third piece of timber is a prop. Another door hinge could be used and nails or screws used to make a ledge for the edge of this to hold the main panel at the correct angle.

The whole thing will look like a small cement mixer.

The CD-R 25 disk outer case will slip inside the 50 disk outer case. They are handily tapered. It needs to be removable as it will wear out. The spindle with its pillar cut off is now a lid.

The spacer disks may have to have the centres cut out and stacked until the centre hub of the CD-R case no longer touches an entire disk and the disk will sit flat and steady. These might best be glued in place.

The glass disk sits on top of them.

The brass donut rolls along the face of the glass disk in a polish slurry. The tilt angle has to be adjustable for best pressure versus the disk continuing to roll smoothly. The tilt must also be there to keep the slurry pool inside not on the floor.

My version uses a Ford 6 cylinder automotive water pump. This yields about 70 rpm with an AC 50hz electric washing machine pump motor driving off a 4mm approx shaft. For 60 Hz motors, the larger power steer pump puley may be need to keep the drum speed down. Buick V6 water pumps have a larger pulley but may be more awkward to mount.

All the automotive water pumps are doing is providing a bearing, a pulley and something with bolt holes in it to mount it with.

For the Aldu disks, a much smaller drum, maybe a small plastic food jar with a pressed lid and a smaller donut would be needed. For contact pressure the donut might have to be thicker for weight. In both examples the donut should not cover more than about 5/8th of the disk diameter otherwise the rolling action will become erratic.

The motor and pumps should be found in waste bins at repair shops. Whilst components essential to their function as pumps may have become completely ruined, often the bearings and the electric motor in the case of the washing machine pump remains serviceable. Do not wire the motor up yourself but have a qualified electrician do it for you.

No warranty of satifactory performance is made either express or implied.

[Wayne Morellini]

<<<-- Originally posted by Damion Luaiye : The present hurdle: Beattie screens use fresnel lenses and the Beattie folks need a focal length spec (distance from eye to screen). With all of the distance variations and diopter configurations we have in our rigs I was unsure what length to give - any suggestions?
- Damion -->>>

It might be better to discuss that with there engineer. I imagine that a standard screen could be made but custom interfacing optics might be needed for each rig (as presently is done from camera to camera). But does anybody here know allready, and has anybody bought that SLR Beattie focus screen to try out?

I have some good news (but I am too snowed under to look it up). I seem to remember in the information on Sony's HAD/hyperhad?? that they use a small microlense screen over the sensor to concentrate light on the pixels. Somebody was talking about this in the formum recently, that reminded me. If they can build them this small we should be able to get this finess too, even HD. So who makes them for Sony (Beattie could probably match this).

[Brett Erskine]

Damion-
Post frame grabs from your setup with the Nikon D screen

Wayne-
Is the "Sony Had/hyperhad" screen made up of a layer of micro lenses or is it simply super fine ground glass?

Bob-
You crack me up. Carry on man!