Hi

Good job, and it is good to see that you guys intend to address the issue of optical problems/distortions.

I've spent over 20 hours (and around 300 web pages) on the 35mm adapter topic, though I still haven't gotten to read this thread fully (a bit reading impaired), but I have some questions.

I thought I saw something, in one of the posts, about a very bright filter/screen/diffuser that worked by having a surface of microscopic lenses/beads that increase light transmission. But I can't find it again and have spent many hours looking and searching through threads. Can anybody help me?

This diffuser reminds reminded me of a coating for TV and computer screens developed over 10 years ago to. The coating would blend in the shadowmask between pixels to hide it and give a pseudo High Definition look, it would be excellent for the projection surface in an adaptor, as it is a controlled substance that would let through the maximun amount of light (compared to the spread in a ground glass).

I have been thinking about optical stuff for a while and I have these ideas. That the courser and higher the diffusing surface the wider the angle of light spread you will get, includng back into the surrounding grain, producing bleed and washout. To reduce this it needs to be finer and thinner. Instead of condensers there should be some matarial out there that will take light from a wide arc and transmit it in a smaller arc. I think the holo diffusers (yet to read up on it) does this, but the micro lense system I mentioned above could also be designed to do this (if not just projecting through the back of it instead). The lenticular lenses could be designed to do this, but being plastic the optical qualities might not be beast.

So what is the best solutions so far for the projection surface? I hear that Louis and Dino are doing adapters with holographic diffusers. How is brightness, contrast and low light ability with these compared to spinning ground glass. I have seen demo footage from different systems on the web and there is a big difference, some are much better than others, but I am uncertian where ever it is the adaptor type, or personal or camera model style? The Marlar movie is great. I can see the light dropping off to black quickly because of the spinning disk, the glimmer of the spinning grain as their arch of movement sweeps reflections outwards, the circular streaking (presumably from the disk), or the encoder), the amazing film like softness and contrast levels. But the Dino one seems more like normal video in contrast and everything, , presumable from a lack of GG grain and softening. I saw another, with a racing cart that was just bright and glary like normal video. There was a number with the soft film look. Of course they all have good DOF, but which systems are best for visual performance?

Is it possible to have a website with a breakdown list of all the solutions and parts, with the science and their plusses and minuses, and links to parts, peoples adapters and example footage?

Thanks

Wayne.

Don't forget about post - Marla was pretty heavily worked in Post. Most of the things you mention as liking about the 'film look' are probably more apt to come from post-processing rather than the adapter's qualities. Color balance and saturation and blooming of highlights being two biggies. In the collection of examples, it would be good to see unaltered footage for better comparison.

I have seen footage before (I remember ceramic tea pots) that seems unaltered but simular. I think the difference is post, but also lighting, they have sequences with center lighting and leaving the rest go to black, and there is a lot of black, a style, I think is, suited to miniDV adapters. Even the new film look in cinema, I think, is also computerised in post production, so I am expecting post production. The problem is that different cameras and lense performances are also going to effect the amount of processing needed. I take your meaning, so we really need to decide which has the best raw footage. The raw performance is what we have to work with in post. So each adapter technique has to be tested to see what it will look like on a range of cameras, could I suggest that Sony PD170 and an XL1s have significantly different picture and probably would be the best reference cameras (for miniDV). The problem is that different adapter techniques coould simulate the XLS1 softness and range, and enhance the PD170, or alternatively look better on the XL1s.

Bob, so what is your final configuration for the agus35 ? you using a plastic GG, discman motor, are you correcting the image or recording it upside down ? post a picture :)

Hello again Agus.

Re: your question above, I have not developed the Agus any furthur and won't until I receive my glass disks. It is my original "plumbers version" made from sewer pipe caps and other plastic plumbers parts. There is an image of it in www.dvinfo.net/media/hart.

I replaced the potplant saucer CD spindle motor mount, which clipped into the housing with a flexible plate style mount which is adjustable at three points for lens back-focus and tilt. There is enough compliance to enable to disc to run true but the mount is stiff plastic which does not slump like the potplant saucer material did.

I have not done any more work on the mirrors or prisms. I'll see if I get my glass disks sorted first. Except for having to invert the image in post it is quite useable the way it is.

With careful adjustment of the motor mount and re-setting the objective lens back-focus which gets thrown out, the image through the telescope lens set can be made so that there is no barrel or pincushion distortion. But in the best position, the camcorder has to be zoomed in almost to the point where its own close-up focus crashes.

There is an image from the final set-up in media/hart.

The image path for the music video and for the still titled Agusprob was :-

Objective Lens = CIMKO 28mm - 80mm zoom.

Nikon Mount = home made from plastic pipe cap.
(This mount allows some backfocus adjustment as it slides on a pipe which runs right through the case and has the camcorder bayonet mount on the other end. There is a cut-out clearance for the disk.)

Rotary groundglass. = CD-R pack clear spacer disk prepared by the pressed method, furthur dressed with aluminium oxide and partially polished back with a soft flannel cloth to improve light transmission.

Groundglass is rotated by a CD player spindle motor, simple 1.5v to 12v DC type (Mabuchi style). The motor is fixed to a compliant plastic plate which is retained by three nuts on pillar bolts and supported from beneath by stiff springs on the pillars. This arrangement provides a second back-focus, camcorder focus and tilt correction adjustment.

Power is from two x 1.5v pen cells = 3v DC in pack fixed inside the case.

The close-up/macro lens set remains the SW5042 Tasco telescope eyepiece lens set, reversed with the composite element itself reversed. This set is in a custom brass mount, home-made to screw into the 58mm filter mount of the camcorder. Distance from front element to groundglass is about 12mm.

The Agus assembly fits around the close-up/macro lens and fixes to the lens hood bayonet mount.

My chosen image frame size is the 4:3 academy motion picture frame of 24mm x 18mm. (Brett Erskine's template). There was no hot spot problem with the image frame this size with the CIMKO lens.

Camcorder settings were DVCAM with electronic 16:9
selected. Shutter speed was 50fps, the image interlaced. Camcorder exposure setting was manual, ND notch 1, f5.6 selected. There is no progressive scan on the PD150P faster than 12.5fps

Inversion, colour, gamma, brightness, contrast and letterbox was adjusted afterward. The image in the clip does not represent the raw image quality.

The camcorder is a Sony DSR PD150P.

When I get some time, I'll break down the Agus35 and photo the current assembly method.

Thanks Rob for putting up the media pages, it answered some of my questions and even answered one I was expecting to research myself. Thank goodness I did not read all the 1000 posts before before seeing the pdf's.

It is interesting that ARRI is offereing a custom ground glass making process (for those that want the softer feel). The glass will probably produce a more subtler image than the variouse holo and reflexite screens I am looking at. So now just to research the optical quality of these holo and Reflexite screens. Anybody allready know if they are highly suitable for HDV, and where ever they distort or discolour the image, I assume they don't do contrast any harm?

Great work guys, thanks and hope to see all your designs when your done.

Hi all, I experimented with static GG adapter (aldu35) but it did not work out for me even with "grainless" Bosscreen material as GG because of the visible grain.

I'm making it for JVC HD10 high def camcorder, so unfortunately (or otherwise) the cam's high resolution imposes higher requirements than the SD cams'.

WMoving on to agus35, rotating GG version.

Looking for a custom-made quality CD-shaped ground glass.

Suppliers?

Just a thought here - at HD resolution, if even the paraffin structure of the boss screen is too visible, I think you'll be bothered by some facets of the inherent 'swirling' grain structure of the rotating glass too. One of the issues with the original Agus is the fact that the imaging happens up on a 'corner' of the spinning GG - which means that the 'grain' is always moving in the same direction. Some people complained about this even at SD. I would think at HD rez, you'd want to think about alternative methods of moving the GG, so as to not have this problem. Possibly a 'vibrating' GG - or one the moves not in a spinning motion but in an elliptical path (like the new version of the P&S Mini does). Whatever you choose, I'd think you'd want the grain's movement pattern to more or less center itself around the imaging area. I've only built a static adapter, so my knowledge here is purely theoretical.

I only mention it because you seem quite serious about building a very high-quality adapter for HD.

Jonathon, I did experiment with the VERY roughly ground blank CD as rotating GG, with a lot of really bad scratches on both surfaces, and still while rotating, it looked so much better than static GG of even highest quality "grainless" Bosscreen.

I did see *some* pattern, but I thought it was because of the rough scratches on CD.

Thus I'm intending to have a quality-made GG in shape of CD and try it. I'm sure with 3-5 micron ground, there will be no more visible pattern on the rotating GG.

Do you know of any optical labs who make such small order items?

And yes I'm damn serious about making a good quality adapter :)

Will report the progress back to the group for everyone to employ it if successful.

With any moving groundglass, the groundglass texture will be "seen" by the video camcorder as a fixed groundglass if the shutter speed is not slowed down, desirably to 1/50th of a second.

This is contrary to one recommended practice of video at 1/100th of second be it right or wrong, I was advised to follow.

In none of my tests have I had any texture from the groundglass showing up except when I forget to turn it on. However where there are large density defects in the groundglass, creating areas of varying transparency, this will show as a strobing effect, especially if the disk rpm is close to the camcorder frame rate or multiples of it.

This effect can be made to emulate the variable density of motion film if the disk surface travels from bottom of the frame to top of the frame as seen in the Agus35 itself, not the camera image, in which it will travel from top to bottom.

As for glass disks, you'll have to polish them locally but Ohara in Japan are prepared to make glass disks of CD dimensions. At a rough guess, going on exchange rates, ten unfinished precision disks will cost you about US$420-00 landed in the US.

If you want the raw disks and a quote for your requirements, contact Hiro at Ohara Glass in Japan. His email is Hiro@ohara-inc.co.jp

Bob

I'm interested in the static aldu35 type design too. So the bosscreen is not good enough, what about the holographic screens and the Reflexite screens, are there any sources of really fine ones? Has anybody got one and tried spining it?

Now heres another idea for dealing with the grain.

As most of us already know the first models of the P +S Technik used a CD-like rotation GG. Because of picture quality and physical size problems the idea was dropped for a better design where the glass is almost vibrated in place.

But I had a third idea...but its much more complicated movement to build. You can get even closer to a "film look" and deal with the grain issue by having the GG rotate and stop 24 times a second (for DVX100. 60 times a second for other camera). The GG would stop just in time for each frame to be captured. The result would be the same beautiful effect subtle film grain has on footage.

Its kind of imbraces the idea of just a little amount of grain in the picture which might help take that harsh edge off of the image that you find only in video.

Now I know what is involved to make this happen in sync as Im sure some of the techs out there do as well and your right - it would be difficult. I only offer it as a third option for anyone that is interested/cazy enough to try it because its sure to give great results.

-Brett

upside down monitor solution
 

just in case you didn't check - take a look at upside down monitor solution thread. the inverting/flipping image problem is finally solved! take a look.

filip

Brett.

You don't need to do that. Just set the disk motor speed slow and camcorder shutter high and it's done.

With my DVD-Video version of my Agus35 footage, which is higher res than .avi files, interestingly there is a faint fine scintillation or random grain effect in the image. I dont know whether this is small bright pinpoints being created by the pits in the groundglass. It is like low-light video noise but is finer. These pinpoints might flash fast enough to register sharply in individual frames. It is visible on a hi-res monitor but goes away when projected or viewed on a standard TV screen.

I made mine with an initial pressing of the 600 grade paper against the CD-R disk. Whilst the surface has been subsequently rubbed with aluminium oxide and back-polished, I suspect the bottoms of the pits originally pressed in, remain and have clean sides, with steeper edges perhaps than pits caused by rolling grit in the conventional polishing method.

If you can play back PAL DVD-Video on DVD+R discs, I'll send you a copy by the mail. It might be something worth going after as an effect.

As for rotating the gg in 25 to 30 ps increments, stepper motors and computer controllers might achieve it. There are kits from electronic hobby shops for this. The motion control people in the video/film industry know how this stuff works.

Wayne.

Holographic screens and reflexite are high science things I don't know anything about, so I can't comment on those.

OK, so if the GG vibrates rather than rotates, then the grain visibly disappears because:

- the grain is moving with the frequency much higher than shutter speed, thus creating motion blur in camera;

- the image projected on GG is NOT moving, thus staying sharp for the camera.

My understanding is that the amplitude of the vibration should be small enough to keep GG within the DOF of the camcorder's macro lens, but large enough to create grain motion that would translate into motion blur in camera.

Correct?

Questions:

1. If I shoot with 1/60 shutter always, what should be the frequency of the GG vibration? (I assume over 2 times higher than shutter, eg maybe about 150 HZ?)

2. What small vibrating motors are available? (Ladies' devices are out - size matters in the inverted sense here...)

Anyone who's already experimented with vibrating GG - please pitch in!

A linear movement will not work, unless electronically synced to the camera frame rate so that movement is always occurring when the image is being scanned off the CCD. Otherwise there will be intermittant frames of a staionary gg. The motion has to be circular or orbital if it is to run at a free speed.

The movement, rotation vibration or orbital motion of the gg is across the camcorder's field of view, not back and forth towards and away from the camcorder. Ie., it does not deviate from the focal plane of the objective lens on front or the adjusted relay focus of the camcorder.

Plastic CD is fine for me
 

I was messing with my Agus 35 today. I just wanted to share with you all that I was very pleased with the images I shot today. No visible grain, no hotspotting and no vignetting. Everything was rock solid. I used all of my 35mm SLR lenses and was able to stop down without increasing vignetting. If I get some time, I'll post some images on my web site. Here's what I used to get my results.

thick acryllic CD spacer ground carefully with 9 micron WAO. (I tried CEO and 5 micron WAO but couldn't get an even enough finish)

Coated double convex rectangular lens, 40mm by 27mm wide by 9.5mm thick at the center. Rounded ends. 63mm focal length
found here http://www.surplusshed.com/pages/item/l1584.html for $3 ea.
The condenser was mounted between the spinning GG and the Video camera, as close to the spinning GG as possible.

I shot with all of the following SLR lenses and had great results with all.
35mm F2.8
45mm F2.0
58mm F1.4
28mm-80mm F3.5 Zoom
80mm-200mm F3.5-F4.0 Zoom

I'm now convinced that the spinning plastic CD is still the way to go for the best image. I'm sure a glass disk will give you better light transmission but how much better? I'm curious to hear how the CD motors hold up spinning the extra weight of glass not to mention the cost. Did I read right? $420 for 10 disks???? I'll post some images asap. Joe

Maybe grinding the acrylic CD very thin would improve light transmission. It's soft and should grind easily. Another CD may be trimmed down to hub size and glued to the ground CD for strength if needed.

Joe.

Yes you read right. It is a ballpark calc. Yes, it is a bit of overcapitalisation for an Agus. I err a bit on the side of technical obsession versus simplicity. Here follows a copy of Hiro's quote :-

""""""""""""""""""""""""""""""""""""""""
I am finally ready to submit my quotation for 10pcs of S-BSL7 D120.0 - 15.0 X 1.2T disks as follows:

1. Glass Type = Ohara S-BSL7 General Optical Properties as per Ohara Catalog Standard

2. Outer Diameter = 120.0 +/-0.2 (mm)

3. Inner Diameter = 15.0 +/-0.2 (mm)

4. Concentricity between OD and ID = 8 micron meter or less

5. Thickness = 1.2mm +0/-0.3 (mm)

6. Surface condition = Ground

Our price for quantity 10pcs is F.O.B. Japan JPY3,400.- / pc F.O.B. stands for "Free on Board".
This means the price includes the cost of the product itself and the cost for clearing customs in Japan.

Therefore the consignee ( customer ) needs to pay international transportation fee. The reason why we offer F.O.B. price is it we have no idea how the consignee wants to transfer the goods ( by ocean-ship, or air-freight, or postal parcel ).
If you have a specific requirement for transportation method, we can quote our price which includes all such costs and you have only to receive the goods at your door.

Please let me know how you want us to ship the goods. Does my explanation help you understand?

Lead-time = 4 weeks after receiving Payment by remittance

End of quote.

"""""""""""""""""""""""""""""""""""""""""

I don't think the true groundglass is going to yield a quantum leap in image sharpness, more like 3% or thereabouts as our images with the plastic disk are already looking good.

Glass will deal with the inconsistent finish when working with the finer grades of polishing compound you mentioned.

That in turn will deal with issues of variable density and flickering.

The CD spindle motors should not have too much bother once they spool up. We are not expecting them to precisely track a fixed rpm with applied power and braking voltages but putting a constant voltage to them and accepting whatever rpm they operate at.

We are also not operating them for continuous long periods as might be expected spinning a CD disk in a player. Provided we are reasonable about the power we put into them they should last the distance.

They may not be as tolerant of violent movements whilst in use, but I suspect the disks, spindles or the motor mounts may fail first.

<<<-- Originally posted by Bob Hart :
Wayne.

Holographic screens and reflexite are high science things I don't know anything about, so I can't comment on those. -->>>

Sorry Bob, I was up all night and must have got a bit confused. Some people are experimenting with ready made holo screens.

I've spent the past week or so reading all of the posts on the Agus & Aldu35, as well as much supplementary info on basic optics theory. The amount of info available in just these two threads is amazing. I've already 'repurposed' an old portable CD player, and started sketching out my design. I have access to a machine shop, so hopefully my first basic design will still be made out of something a little more sturdy than an empty CD-R package. My optical parts should be here soon.

I've decided to go down this path:

Nikon lenses attached to standard mount --> Maxell frosted CD spinning on a portable CD player subassembly --> glass condenser lens (with convex side pointed away from gg) --> an achromatic diopter (if needed, my Sony seems to be able to focus correctly to closer than a half an inch with no help) --> Sony TRV-9 cam with 37mm lens mount

I have the design from the 35mm lens through the gg pretty much finalized, but have a couple of questions after that point. First, the lens mount on the Sony is 37mm. I was planning on just using a step-up ring before attaching to the Agus35. Then keeping the condenser lens at a larger size, so that I can use the same unit with various cams. Does this sound like a good idea? Or would I be better off in keeping the lenses after the gg on a 37mm mount? Will keeping the condenser lens at a 37mm diameter not work because there will still be vignetting? Is there any practical difference as to the amount of light that is lost due to a different lens diameter? I really want to stay away from glue and the like, and would rather have the unit be easy to take apart and modify over time. I also want the system to be as basic and optically efficient as possible. Does anyone have a good source for step up/down rings of various sizes?

I'll be sure to take pictures along the way, as you all have done, and will also throw together a small description of what was decided on, and why.

For the Agus35 I'm working on, a flipped LCD - with image corrected in post - will probably be used, seeing how flipping the image optically is currently too cost and size prohibitive. The Aldu35 will hopefully be corrected optically using a 45 degree first surface mirror and a roofed pentaprism, such as in a SLR (I love the design of that ARRI Digital Viewfinder). Of course this depends on whether or not a suitable pentaprism can be tracked down. Any new leads available?

Joe, could you please post a few photos of your Agus35 as well as the test frames you mentioned? I'm interested in seeing how you mounted that rectangular DCX from Surplus Shed. It's good to hear you're getting such nice results.

I can't wait till I can finally use DoF in my shots. I've never been satisfied with the permanent 'infinite focus' effect built into video.

Ray

Successful test!
 

Just tested the vibrating GG - successfully!

I simply used the Nikon's focus screen as GG, and attached a micro vibrating motor from old cell phone to the side of the GG's frame.

While GG stands up vertically, the motor is attached horizontally to its side.

As a result, the motor's vibration does not change the GG's distance from the cam's lens, but rather moves GG across the cam's view.

Result: it definitely eliminated all small imperfections which were otherwise highly visible with static GG.

Larger areas where GG's structure is uneven were less affected - due to the fact that the amplitide of the vibration is rather small.

So if GG is quality ground with say 3-5 micron grit, no scratches/blemishes/eneven areas, then my test shows that the vibration will completely eliminate any visible grain.

I'm now cautiously optimistic that a HD QUALITY, wonderfully small home-made adapter is possible.

Because no-one (unless i missed it) produced such adapter, do you guys think we should open a NEW thread for it and call the adapter maybe buzz35 or vibro35?

(It seems custom to call adapter variants by the name of their developers, but alra35 does not sound right to my ear :)

maybe RAAL35?
 

alex,

can you pass us some footage or jpgs?

it sounds very intersting. what kind of motor did you use - from which phone (model/manufaturer etc)?

some times ago i bought for the same reason (someone already mentioned that in thread - the vibrating motor for cellphones) the stand alone vibrating gadget for cell phones, but i do not know how to change pulsating character of it (buzzz-silence-buzzz-silence-buzzz... etc), so maybe your knowledge will help us.
how dificult is this to build?

filip

Re: Successful test!
 

<<<-- Originally posted by Alex Raskin :
While GG stands up vertically, the motor is attached horizontally to its side.
-->>>

i forgot to ask you about above - can you describe/ draw/picture this in more detail?

thank you

filip

I might have a lead on cell phone and pager vibrator motors if anyone is interested... I believe they are sold in lots of 10

Alex,
I'm curious as to how you are insulating the rest of your adapter housing from the vibrating motor. I experimented for a while with a homemade oscilating motor using rubber bands to suspend the GG/condenser assembly but I could never get the thing to be quiet enough for shooting and the whole box vibrated terribly. If you licked that problem, then you are definately on your way to a compact, high quality adapter. I look forward to hearing about your progress. Joe

PS: Welcome to the addiction Ray,
I will post some pics on my web site soon. I just have to take some snapshots of the Agus 35 and upload it all to my web site. Should be just a few days. You wouldn't happen to know a Sony engineer would you???? ASk around. The answer to the inverted image is in the camera.

New thread for vibro adapter
 

Please continue here:

vibro35 adapter

Its probably a better idea to continue this topic as a new thread on the main Alternative Imaging Methods forum because a moving ground glass will apply to all upcoming HDV camcorders and not just the HD10.

To reduce vibration, mount the motor and screen assembly on a floating mount, springs, bands or whatever with a low natural vibration period.

There will be a need for lots of compensatory mass to be attached to the motor mount otherwise the motor itself will move instead of the screen. Lots of compensatory mass means extra weight and difficulty keeping the groundglass on the focal plane without vibration and noise being conducted by the guide system to the case.

Unless my recollection is faulty and yes, it often is, Agus Casse initially went this route and changed to the rotary groundglass.

Unless the groundglass can be kept really light, thin and small, the vibrating system may be a design dead-end.

Had an idea for a simple vibralens or vibrafilter. Mount a GG from a 43mm filter to a 52mm (or larger) filter's mount with rubber contact cement. It shoud mount securely, yet still have a little play. Then attach an earphone without the plastic earpiece, and strip the speaker down to the magnet and cord. Then plug the cord into the earphone jack on the camcorder! There should be enough vibration to obscure the grain, but should still run silent.

Fresh Agus 35 images
 

Hello all,

For anyone interested, you can see some images from my Agus 35 here. Just click on the pic with the Agus 35 rig. There are frame grabs, a test clip and design photos. I look forward to reading your comments. Thanks! Joe

http://www.paddlefilms.com/35mm adapters.htm

You'll have to copy and paste the link to your web browser.

Joe.

Sorry mate. The address you give above either throws up a Google Search page on 35mm adaptors or the following message :-

""""""""""""""""""""""""""""""""""""""
Bad Request

Your browser sent a request that this server could not understand.

The request line contained invalid characters following the protocol string.


Apache/1.3.27 Server at www.paddlefilms.com Port 80

"""""""""""""""""""""""""""""""""""""""""

Just change the space to %20 - try this:

http://www.paddlefilms.com/35mm%20adapters.htm

(urls can't have spaces - they need to have 'url encoded' characters for most anything except letters and numbers)

oops
 

Sorry all,

I've renamed the page so there shouldn't be any problems now.

http://www.paddlefilms.com/35mmadapters.htm

Let me know what you think, Joe

PS: The corrected link posted above by Jonathon won't work now. Thanks Jonathon for doing that. Can anybody email me how I can be able to post an active link?

Yeah, no problem... just wrap your address in a url tag in open brackets (I can't type it, but it would be... pretend that the parenthesis in the following are square brackets:

(url)http://www.somepage.com(/url)

put the slash in on the last part. This will link the page.

There's more information on these kinds of things at the following:

http://www.dvinfo.net/conf/misc.php?action=bbcode

Joe.

Seen the pics amd they look good. Seems like you've got it sorted. Grain and spots on the disk?

I don't know about the PDX10. I believe it's the PD150's little bro.

I suspect it may have the same offset CCD arrangement as the PD150 as I notice the cropping comes in on the left corners where it appears at all.

At 30 fps, the camcorder may be seeing massive over-exposure and clamping the shutter speed really tight.

This means that stuff on the disk surface is going to be frozen. You'll get it randomly frame-by-frame like film grain and dirt on film and you won't easily see it on monitor playback.

You may not see it on a smart progressive scan TV at all if it is sweetening the image. (That's a rumor, not established fact proven to me).

You may have locked it at 30fps but you may have to use a ND filter in the image path somewhere if there is no other separate also lockable setting for light or gain adjustment available that the camcorder does not automatically compensate for.

ND's will force the camcorder to see low light and lower the shutter speed for a given selected frame rate.

Ideally it should be in the region of 1/60th of a second to get similar motion smear to film though 1/120th or thereabouts has been suggested to me to preserve better apparent resolution.

Slower than that and the PDX10 may do a PD150, halve the frame rate or dump one of the fields which lowers resolution.

I guess the easiest way to fit ND filters will be to make another slot in your condenser lens holder and slide pieces of filter gel into that. Make it thick enough that you can stack them or make an insertion holder like a Bolex or CP16 uses.

Thank you Jonathon for the info on posting live links. I bet there are many regulars here who will find the info useful.


Bob,
You're right. The PD100A is the lil' brother of the PD150. I meant that the PDX10 was the next generation of the PD100A. The PD100A isn't being manufactured or supported by Sony any more.

My camera allows me to adjust both shutter speed and the iris sumultaneously so I don't believe it is automatically adjusting for an over bright image. I can surely over expose the image if I want to. It also has a "push-button" ND filter (can't be optical) which helps cutting down glare and evening out luminosity of the image. I certainly get a sharper image with 60fps. I believe the softer 30fps image is due to motion blur of the spinning disk but I could be wrong. I definately see the motion of the spinning disk at 250fps or higher. At that speed, the image sort of "throbs" giving it a homemade film transfered to video look. It kinda reminds me of old 8mm movies transfered to video. When I get a chance, I'll post some test grabs at various frame rates.

Right now, I'm working on a mirrored hood that will allow me to completely correct the image in my monitor without surgery to the flipout monitor or having to buy a seperate monitor and mount it upside down. It is based on the "roof" of a roof prism. I tested with two rear coated mirrors mounted at 90 degrees to each other. I 'm now ordering optic quality, surface coated mirrors so I can build a proper monitor hood. I'll post pics when It's all ready.

Thanks again for the tips and info,

Joe

http://www.paddlefilms.com/35mmadapters.htm
here's the direct link to the site (thanks again Jonathon)

I have played with a roof array for image erection into camera. For that purpose it has to be huge and totally impractical.

For your purpose I guess it will work and for a practical light box which will not bring your face too close, the mirrors themselves may not have to be too long to get the field of view you need for the LCD screen. You may find the thing getting a bit heavy to handhold that far outboard and possibly vulnerable to transport damage.

If you need it to be shorter, you may find four smaller mirrors as a porro prism array may be easier to manage. You might be able to bring the viewport back over the top of the camcorder but the porro arrangement would be extremely ugly.

On "www.dvinfo.net/media/hart" under "aguserector" you may find some info on my experiments.

hey Bob, i forget to post the solution for the image correction when shooting, i have a lot of work and the oportunity of my life in the door next to me, ( making my first tv show with my own company at one of the mayor tv station in Guatemala, and i am only 21 years old ! ).

So... have ever think of using a roof prism in the viewfinder in the camera ? not the big LCD screen, the little viewfinder, that we barely use cause we love the big screen :)... Well i order a few prisms and i test them with my TRV, (havetn test any of the adaptor stuff with my DVC80 yet.) and they work perfectly.

Heres the link and they are really cheap, i got 5 of them so i could experiment with a few of them.

http://www.surplusshed.com/pages/item/l2080.html

1 thousands thanks for keeping the Agus35 project alive, and hope to start working again in a new version. Thanks a lot Bob

Agus Casse

Agus; Its funny you should bring that up; I just ordered the same item last week and am waiting for it to arrive!