Chris.

A quick and dirty way of getting the axes near correct is to take care of the camcorder end of the adaptor first, then once this is fixed, drill a small pilot hole in the case where the SLR lens mount is be in the spot where you think the centre will be.

Mount the device to the camera, look through your camera viewfinder for the pinhole with your camera zoomed to its correct position. If the hole is off-centre, use a small keyhole file or hotwire to widen the hole to move its centre.

The hole must remain circular, just larger, otherwise some optical bads happen which misinform you whether it is centred or not.

Once you have the hole centred in your camcorder view, mark out your lens mount hole from it. Don't use an electric drill powered hole saw with this hole as a centre for the arbor bit. A hole saw simply is not precise enough.


FOOTNOTE: ( with PD150/PD170 cams there is an optical issue which will work against the option of direct aerial imaging without the GG installed if you use this construction method ).



GENERAL INFO:

For anyone using the AGUS35 or similar as an aerial image relay (with the groundglass removed).

When using camcorder autofocus in bursts with long lenses to track dynamic subjects moving towards or away from camera, best practice is when opportunity permits, to reset the SLR lens to its infinity mark, sight the lens on an infinity subject which has lots of texture and contrast, then trigger the autofocus to reset the camcorder lens.

There is a tendency when using short bursts of autofocus, then trimming with the SLR lens for the next action, for the aerial image plane to creep towards the back of the SLR lens.

This makes more apparent, any soft blemishes from dust which settles onto the back of the lens during the day, increases the likelyhood of an autofocus pull to the back of the SLR lens when soft plain objects like clear sky come into the frame, such as momentary loss of an aircraft or bird out of the frame when the autofocus has been left on to track the movement.

I know cleanliness is next to godliness when it comes to optics however some consumer longlenses by nature of their design are not sealed against environmental dust and cause by the zoom function a lot of air movement in and out through the adaptor which if it is not cleaned out frequently will pass dust onto the back of the SLR lens.

While doing some imaging of the Red Bulls Air Race, with the Sigma 50mm-500mm and a doubler, at the 1000mm end, this became a real, almost unmanageable problem.

Red Bulls = a very enjoyable event by the way. It's coming to Perth again over the next two years I believe.

Hi Bob,

Was just reading some of the old posts and I came across this one. Just asking for some advice from you if you don't mind. My MX500 (PV953) needs a +7 diopter to get the image grabbed at around 4X zoom. I tried +4 and +3 individually and they just don't work. I know some camcorders don't need any macro. But for some that do, is +7 diopter the only one to use? Thanks.

Alex

Alex.

A general rule of thumb might be that for a 1/3" CCD 16:9 camera, you might need at least 54mm zoom-in, for +4 to work onto a patch of GG 24mm wide, from about 120mm away from the groundglass.

A 1/4" sensor, with the same setup might cover a smaller patch of the GG. The camera zoom might be able to be pulled back a little.

Distance of cam from GG, magnification power of the dioptre, camcorder CCD size, maximum zoom-in of the camcorder lens, ability of camera to focus on close objects, all interact to set the limits.

4+ is right on the bottom limit of magnification power which will work for 24mm wide off the GG. This 24mm is about the widest image on the GG which will not give you problems with variations in light diffusion through the GG which gets called variously hotspot, edge falloff, dark corners etc..

A wider size image will get you better apparent resolution, as the groundglass texture is scaled smaller relative to the total image size.

The balance is tipped away from uniform light diffusion which has to be cured with condensers or coarser groundglass texture. Both of these workarounds affect resolution to some degree and add complication for the home builder.

My first device was not a flip version. The power of the 2" telescope eyepiece I used came out at more than 12+. It included in effect its own BCX condenser only I didn't know it at the time.

It only had an entry diameter of 44mm. Fortunately the PD150 zoom-through at maximum was enough to get inside the rim of the lens.

I have to leave the discussion at this point as work beckons and have rushed this a bit.

For non-flip adaptors, +7 to +10 seems to be the more common dioptres of choice. For a flip adaptor, the options are narrowed by the flip path and some cameras may simply not work.

Bob,

So you are saying for flipped adaptor, it is only limited to a few camcorders in the market and not all even with different diopters magnification strength in the market? An easy way i guess to test if a camcorder can zoom in to see if it will frame a 24mm wide GG is to have the camcorder positioned at the correct distance away from the GG, i.e if the adaptor has a light path of 120mm say. Then place a GG size rectangle on a white sheet of cardboard and zoom in using different diopter strength. What do you think?

Alex.

To get an image off a groundglass into a difficult camcorder, anything is possible depending on the will and means to get it done. But the reality is that most home-builders are hoping to come in at sub AU$1,500 which takes the more elegent solutions off the table.

Beyond a certain point, even factoring in the labour savings of doing it yourself, a person would be better served buying in or renting the real thing and converting their own labour into an offsetting profit to pay for the commercial device.

Your method is the way to go and a path well proven by others.

A handy jig is to get a piece of wood about 40mm long, about 80mm wide, about 15mm thick, - doortrim or architrave is fine. Screw or glue underneath, two cross pieces to get it up off the table and stop it from falling over.

If you can find a friendly woodworker with a router, have him cut a slot about 10mm wide for most of its length.

A dummy camera, (block of wood) with a centre axis accurately marked and a tight string or rubber band (even thin cutting from inner tube strip) going from a small curtain wire hook to another fastened to another piece of wood on the opposite end can help set up centres.

Cut a whole lot of scrap pieces of plywood of varying thickness to use for spacers or packing pieces and drill holes through the centres for bolting through to camcorder tripod mounts.

Cut up some automotive or motorcycle inner tubes. These make handy instant straps to temporarily hold things in place.

Prism erecting or flip devices have a practical minimum camcorder to GG distance as the prisms themselves take up space in the path and shorten the distance from camera to GG by bending the path back and forth. Mirrors do the same.

A non-flip device can be a lot shorter. In the case of my telescope eyepiece, the usable distance from the dioptre to GG was 12mm to 18mm which enabled a handy close coupling of the camera and device for handheld operating.

This handyness is what I have tried to copy with the prism device and have gone with the 7+ which was about as close as I could get to the groundglass and still be able to fit everything in.

With an adaptor, within reason, the closer you can get, the better you will be because you can then back off the zoom to preserve more light transmission. Most consumer/prosumer cams lose some light zoomed right in and sometimes the edge or corner sharpness is less than impressive.

Some cams also have their own corner falloff issues before you add more by fitting an adaptor which aquires a wide image off the GG.

Once you start going as close as I did with the non-flip version, things like pincushion and barrel distortion and chromatic abberation (rainbows) start to become a real headache.

Tripod mount holes and lens centre axis are rarely on the same line in most cams I have dealt with. The Sony PD150 family lens centre and centre of CCD also do not co-incide. The Canon GL1/XM1 family is said to share this trait but I have not confirmed this myself.

This is not a huge issue unless you are relaying aerial image without a GG to attach really long lenses such as the Sigma 50mm- 500mm with doubler, then things get interesting.

Hope I have not added to confusions.

Alex.

In my haste to answer your questions, I did not realise you had quoted a previous post of mine in grey highlight so my replies have probably looked like the ramblings of a madman.

I'll try again.


"""""""""""""
So you are saying for flipped adaptor, it is only limited to a few camcorders in the market and not all even with different diopters magnification strength in the market?

--------- If the camcorder is 1/3" CCD, can zoom in to at least 54mm, the +7 dioptre will get you inside the 24mm wide movie frame where hotspots and other complications are a lesser problem.

The FX1/Z1P with a 7+ and about 120mm from lens to GG will give usable GG images from about 32mm zoom-in to 54mm zoom-in which is its maximum.


An easy way i guess to test if a camcorder can zoom in to see if it will frame a 24mm wide GG is to have the camcorder positioned at the correct distance away from the GG, i.e if the adaptor has a light path of 120mm say. Then place a GG size rectangle on a white sheet of cardboard and zoom in using different diopter strength. What do you think?

--------- Your method is the same that I used. - As close to the groundglass as the structure of the adaptor and the power of your close-up lens (dioptre) will let you and keep sharp focus is best, yet still correctly frame the image area you want off the groundglass.



When you build, you need to keep the camera position rearwards about 2mm from the closest position to the GG where the camera-dioptre combination will permit sharp focus, to allow for construction errors and still have camcorder focus adjustment to enable final sharp focus on the GG.

Do all your setup tests with the camcorder aperture on a wide setting, as this will help reduce any mistakes in positioning the camera which might not be apparent with the deep depth of field a small (high f-number) aperture setting will provide.

A short clip of aerial image relay imaging of the Red Bull Air Race final 2006 in Perth is here at Youtube ( poor res images )

Lensing was via Peleng 8mm and Sigma 50mm - 500mm zoom. Relay via AGUS35, Camera HVRZ1P.


http://www.youtube.com/watch?v=RnfnlMt_7FE

and here at Filefactory (34Mb .mpg manual download only)

http://www.filefactory.com/file/6c2ce7/

A still-image of the camera/adaptor combination configured for ground-to-air aviation videography is here (plus my scruffy overweight profile) :-

http://www.filefactory.com/file/9428f5/

All other filefactory clips referred to in my previous posts have now timed out.

Another "Kill Devil Hills" live performance music clip "Nasty Business" is here :-

http://www.youtube.com/watch?v=TWg2AW91D9w

Origination was as for "Boneyard Rider", Two Sony FX1 HDV cams, one fixed as master, the second fixed as backstage, the third a PD150 with AGUS35 and Nikon 85mm f1.4 lens as the roving cam.

The assembly/edit is rather rough. In an attempt to preserve apparent resolution under minimal lighting conditions - the band prefers to perform in subdued lighting, - the 4:3 and 16:9 frames have been letterboxed.

A music clip shot direct-to-camera with Sony HVR-Z1P, Canon XL1 and via Canon XL2/ LETUS35XL can be found here.

http://www.youtube.com/watch?v=NXyJZHPYPP0

I also shot footage on an AGUS35 but did not use it in this clip except the very first shot through the window of the booth with the blue mike in frame.

I had my greasy hands on the JVC HD100 and Mini35 combination again today. It was on the set of a Vietnam war era movie project which is being shot on Super16. The Mini35 footage was being shot by an industry professional to compare later with super16mm footage.

Their AD has worked on Star Wars so knows what he is doing.

Slightly off-topic, this Mini35 was bought into the country by the owner in part because of exposure to my own home-made adaptor with which I had demonstrated the groundglass relay principle.

The operator was not able to remain on the shoot due to other committments so despite my own deficits as an operator I was give the opp to drive the machinery.

Firstly I was impressed with the optional "handlebars" on the front. These can be arranged in a wide variety of positions.

The one I found most useful for handheld was right grip in about the position of a CP16 film camera although the grip is actually furthur forward.The left bar and grip were arranged downwards to make contact with the barely distinguishable boundary between my upper chest and ample gut.

In this arrangement it was very easy to keep the camera steady when standing upright. I didn't do so well when trying more awkard shots, most likely due to my age and lack of exercise in these working postures.

The arms also allow improvised fixed camera setups in lieu of a tripod. At the end of it all I did not feel like I had been run over by one of the army jeeps my own gadget would make me feel like.

The JVC is greedy for battery power. Conveniently, the Mini35 is less demanding on the JVC battery so when the camera battery itself drops dead, it can be switched to the Mini35 and the Mini35 battery will power the JVC for long enough to get a few more shots until the replacement batteries can be fetched or recharged.

I also shot some footage with the FX1 and Agus35 with the same prime lenses so will be interesting to see comparisons although the setups were not identical. I continued on shooting shadow footage with the Agus35 after the JVC batteries ran down as we only had the one pair.

Some observations - The Mini35 is superficially similar to the home made Agus35 to set up but there are some significant differences in behaviour. The groundglass has a nicer white.

In bright lighting conditions where with my device on the FX1, I might choose ND1 and a very tight relay aperture, this practice will provoke a moire artifact in the JVC when the GG motor is not running (when setting up relay focus).

With the motor running some indistinct GG artifact can be seen but this is only under very hostile aperture settings. ND2 and wider relay aperture works best. This suggests the low light performance of the Mini35 is going to be better than my own project.

There is available the choice of a common run button for both the Mini35 and JVC camera. Due to my unfamiliarity with the JVC, I chose to switch them separately like I do with my own adaptor. This brought me undone once or twice when I forgot to turn on the Mini35.

I get the impression P+S have been conservative in their advice of how to use the Mini35 to keep people operating within a safe and reliable performance envelope. I shot f11 on the prime lens by error with it and didn't pick up any bads in the image.

The location of the shoot was a set which is a recreation of a Vietnam War army firebase. They had all manner of military hardware vehicles and things like genuine Wisconsin 24v power plants and radio comms equipment. They also had lots of extras moving about.

It was a great experience to shoot the shadow stuff against those backdrops and see people who know what they are doing at work and play. (I also blotted my copybook by stepping into a shot so like a bloke on another project long ago who loaded 7240 into mags back to front, I'll probably get a DCM.)

I did not have exact prime lens equivalents to the focal lengths chosen by their cinematographer for the comparable fields of view, so I chose the closest I could find and erred on the wide side.

I shall not disclose any details as the project has its own promotional program which I do not want to cause any problems with. The morale and committment I observed was remarkable. I am looking forward to seeing this one when it is released.

Furthur to above, I have consent from the production entity of "The Eleventh Soldier" to post some of my AGUS35 shadow footage. I have yet to capture and assemble the little I shot with the Agus. Most of the shadow footage I shot was on the JVC HD100/Mini35 combination.

After having a play with that, my own gadget seemed decidedly secondhand.

I shot it on my original prototype as the current one has the GG removed for ground-to-air videography of aircraft. There is a fault with my images. The groundglass alignment on the prototype had gone off.

I dropped it, fortunately the groundglass didn't break but the jolt chipped the front prism, luckily only a corner, out of shot. The upper and and lower backfocus adjustments where knocked out and the lower portion of the image was off the focal plane though it looked okay in the viewfinder at the time.

In meantime, to see some on-set still images of this remarkable movie project, go to www.fotograf.com.au (homepage) , Click on "your photographs", then on the menu that page offers, click on "Eleventh Soldier 10th" which is the day I was there.

The website of the project is here :-

http://www.cinemascorestudios.com/th...dier/index.htm

My own images, when I upload them should not be regarded as representative of the production camera footage as my own camera positions were different and my own images are inferior.

Here's the images I promised at this address :-


http://www.youtube.com/watch?v=S69rcLasmpY

They look good on the computer and on DVD-Video but by the time mp4 compression has had its way with them they look dreadful.

If anyone has any clues to offer on how to get from Cineform lossless HD to Youtube with some vestiges of clarity intact, I would greatly appreciate your advice.

I have tried to export to a .flv file and Youtube's system rejected it.

I called by the director of The Eleventh Soldier to drop off a disk of my assembled shadow footage which I had already posted.

While there, I saw a 30 second action sequence with a full sound mix and music underscore, assembled from the recording of the video tap. It was shown in a small preview theatre with a full-on sound system.

The film is still being processed. Even with the safe area markers from the viewfinder in the vision it, was still a wild event and that sequence will not disappoint viewers.

There was also some standard definition MiniDV footage with the Mini35 which had some regrading done to it. On the big display screen it looks quite good so the JVC HD100 progressive footage should look even better.

It is remarkable how good standard definition MiniDV can be made to look and sound, so am looking forward to seeing the actual film vision when they get it back and done.

On YouTube at this address,

http://www.youtube.com/watch?v=RGM0GBiwEA0

I have posted an indifferent quality SD originated clip from my home-made AGUS35 APVE into a Sony PD150. It was a demo scene from a screenplay. It was shot in the flourescent equivalent of about 400 watts of light, set up as best I could manage it in condined space in a traditional key-fill layout.

On Youtube at this address,

http://www.youtube.com/watch?v=7RTupPYGThE

I have re-posted the 4+ achromatic dioptre long setback clip which was originally at the filefactory in higher resolution but has since timed out.

The resolution at Youtube is as expected but illustrates the corner falloff issues well enough.

I have just dragged this thread back upstairs for an enquirer from YouTube to look at. I have referred him to the Redrock DIY page which is found at http://www.redrockmicro.com/diy_guide.html

Furthur bump for some other researchers.

Andrew or Poppy. This is the thread which tells much of the story. If you go to page 1, there is a post by Chris Hurd which links to a condensed version of this thread.

Some info for idle interest sake.

Of late I have been repairing and servicing a CP16R 16mm motion picture camera for use by a media student. It had been in storage for nine years and had deteriorated. That adventure is another story best left untold.

After resetting the viewfinder screen backfocus to match the film plane idle curiosity led me to grab the Agus35, put the Nikon adaptor and a lens on the CP plus the 7+ dioptre and shove the Agus35 handheld on front.

It would seems that one of these things could work on front of a 16mm film camera. What the resolution would be like at the end of it all is another matter.

Updating:

I am using the Cinevate 72mm achromat on my DIY adapter, which was loosely based on the Redrock DIY plans. I am having to use an extension tube of about 5 inches from the front of achromat mount on FX1 to ground glass. I can then zoom from about 30 to 50 on the FX1 without vignetting.

I have managed to enveigle my way into a music video shoot going on here in the West. It is being shot on the new JVC HD250 and a Mini35.

I assembled my own gadget onto a Z1P and compared the two images. I don't have a direct-to-camera comparison between the JVC and Sony safe area frame markers.

Assuming both are the same, the Mini35 for a 14mm lens is yielding a wider field of view than my own device with better apparent resolution. To get the same field-of-view, I have to use the 12mm-24mm on wide.

The DOP/videographer is an industry professional and is using a real steadycam.

He is apparently doing some beta testing for JVC and he has this black box with a small LCD display on front which attaches to the camera body and records to a hard drive of some kind.

It appears I shall have to revisit using the 4+ dioptre and the longer setback on my design until I can get round to redesigning for the odd sized prism pair.

The 14mm lens is being used for motion moves down a dark and dingy corridor. The advancing or retreating motion is accentuated by the corner stretch of this type of lens which is designed to render straight edges all the way across the frame. Looks good.

I shall try to shoot some comparison footage if I can do so without causing disruptions or getting run down.

Furthur to above, I did not get to shoot any shadow footage to compare with the Mini35 on JVCHD250, of the music video today due to confined spaces and the urgency of keeping the shoot on time and on track.

However, the Mini35 had inhaled a piece of dirt from somewhere and it fell to my task to assist pulling it apart. The owner had some trepidations but also met the necessity of learning to do it on set for the sake of being able to in the future should such come to pass.

I had no such trepidations. The owner suggested such, knowing full well I would not mind in the least, the chance of peering into the entrails and reading its future. Well in truth, there was a little concern I might do harm however this concern was illfounded.

The Mini35, once dismounted from the camera is fairly straightforward to deal with for dust contaminants for someone with a small flat bladed screwdriver and good mechanical facility.

In this event, we dismounted the camera and dealt with the Mini35 whilst it was still mounted to the steadycam sled, a handy loft as it turned out..

Four screws removed and the back panel with the entire prism block comes out rearwards, cleans easily and goes back on within half a minute.

Interestingly for me, I had examined such a construction method for my AGUS35 but because I was designing something which could tolerate construction errors of up to 5mm, it was an approach I abandoned - stupid me.

They had a Seitz follow focus for the steadycam and set it up to run my 14mm and 20mm Sigma for Nikon mount ultrawides.

Although these are not geared, a rubber tyre created by a thick red rubber stationery band was sufficient for the follow focus gear to move the lens focus with acceptable accuracy.

Autofocus lenses when switched to manual offer very little operating friction, so the follow focus worked. I am not sure how much sideloading these lenses will tolerate over time, so proper gears should be fitted. If the lenses are allowed to hit end of travel, they will rock slightly in the mount.

All in all, an interesting exercise. I shall post the YouTube address when I know it.

Deleted double post.

Be Careful What You Post In The Public Domain
 

Be careful what you post in the public domain.

A while back, I posted a clip of the Red Bull Air Race in Perth as a demo of aerial image relay via an Agus35 style device.

Now, clicking on the link yields a big red sign which alleges copyright infringement by myself. There is no means to publicly plead to the contrary and realistically would most likely clog Youtube into oblivion if such got started.

I posted into the clip description text, an explanation and expression of regret for inconvenience to people who follow links from here and other forums to look at the clips.

However, the explanation does not get to first base as the clip is excluded from direct linkage and the clip info can not be accessed.

I published a large diatribe in a centre section in this post but on reflection it served my need to vent my spleen but did little to inform so I have edited it out.

As you might guess, I am a little bit vexed. As a film-maker and writer, I am more sensitive than many punters as to the desirablity of respecting the original work of others.

The lesson I guess is. Don't point your camera at any public event as some corporate entity can claim dibs on your footage and turn you into a cheating fiend with the click of a mouse button.

To remove the red letter announcement from YouTube that I am an alleged copyright infringer, I have deleted all clips and am closing the account, so none of my youTube links I have posted in this forum remain working.

Here are two new links for AGUS35 and LETUS35 origination to replace those lost when I closed my YouTube account.


The Eleventh Soldier. - http://www.brightcove.com/title.jsp?title=572028460

This clip was shot entirely with a home made AGUS35 device on a Sony HVE-Z1P.


b-movie heroes. - http://www.brightcove.com/title.jsp?title=570589631

This clip was shot direct-to-camera on Sony HVR-Z1P for the fixed high-viewpoint master wide,

direct-to-camera on a Canon XL1 for the fixed body level wide,

on a LETUS35 flip for XL on a Canon XL2 for the roving and close-ups

and on a home made AGUS35 device on a Sony HDR-FX1 for the point-of-view control booth with the blue microphone in shot at the head of the clip.

The resolution on Brightcove downloads appears better than on YouTube.

For casual interest and to bring Agus Casse' original thread back up :-,

I have also done a short test of an Agus35 during other tests on a repaired CP16R Super16 gated film camera via the camera's 10-150 Angenieux lens and a Century +4 achromatic dioptre. The lens setback was not enough to use the +7.

A collateral benefit is being able to use a wider path through the prisms and thus a wider image off the groundglass at closer to 27mm and thus sneak a bit more resolution.

The 10-150 is NOT a Super16 lens but at about 7/8th zoomed-in it is.

The image outdoors looks a little oily compared to direct-to-viewfinder screen images with the same Nikon lenses.

I now have to how work out how to get good screen grabs.

Insane? - Probably.

The Ultimate 35mm film emulation obsession.
 

Regarding the AGUS35-onto-16mm-film test, I received a message back from the telecine place to advise me the film test was "all good". Does that also mean the AGUS35 footage?????????

Now I "am" looking forward to receiving the film and the telecine dub. The downside is I had to have it telecined to MiniDV so there is a resolution loss in SD. Still I can look at my pieces of film on a microfiche reader to see just how sharp it is.

Older Clip made with earlier Non-flip AGUS35
 

At the following YouTube address is the full version of the truncated motion clip previously posted at www.dvinfo.net/media/hart.

http://www.youtube.com/watch?v=Zxfjt0Y-EXk

This clip was shot with an early non-flip version of AGUS35 I called the Australian plumbers version because of it being built of sewer pipe and pipe caps.

The relay lens was made with the optics from an unbranded 50mm 2" telescope eyepiece for Tasco scopes. The packaging bore the product ID of SW5042. It comprised an achromatic doublet and a biconvex element. Used in reversed orientation, the biconvex element behaved as a condenser.

It was a powerful but difficult lens system to set up. The front of lens to groundglass distance was only 12mm - 18mm which enabled a very close couple to the video-camera. This was convenient for handholding but as a non-flip system, handheld framing and focus was very difficult.

I moved on to building an erecting or flip version using prisms and abandoned the telescope eyepiece optics for the less powerful 7+ achromatic dioptre which was set back from the groundglass far enough to allow the prism pair to be added between the dioptre and groundglass. No condenser was used in the prism version.

The distance from front of video-camera lens to this lens group was critical. Too close or too far and barrel or pincushion distortions became eveident.

The groundglass disk was a clear CD-R spacer, not glass. The initial groundglass texture on this disk was pressed into the plastic with 600 grade silicon carbide wet and dry abrasive paper and a generator bearing for a pressure roller.

The disk was later refinished with the more common method of aluminium oxide abrasive water slurry.

The clip was initially assembled and titled in Premiere6. The image flip was redone in Adobe After Effects and the filmlook methods published here at dvinfo were also applied.

Insane? - Probably. Agus35 To Super16 Film Test.
 

I had to do a shutter timing test with a CP16RA film camera converted to Super16 so also stuck the AGUS35 on front with gaffa tape and shot a short test of this as well.

The framing is a little bit wide as I do not have safe area markers on the film camera for Super16., so I picked up the edges of the prism path on the lens test itself. I framed wide on the test chart to show the edge of the disk and compare aerial image to groundglass image in the same shot.

I forgot to fit the 85 correction filter so the image is a bit blue.

http://www.brightcove.com/title.jsp?...nnel=570698206

First Clip on AGUS35 APVNE - 600 GRIT PRESSED GG.
 

Another oldie.

This clip was shot on my first AGUS35, a non-flip version close-coupled to a Sony DSR PD150 PAL videocamera. TheSLR lens was a f3.5 55mm Micronikkor.

The adaptor used the reversed SW5042 telescope eyepiece lens set and groundglass made of plastic CD-R spacer, a sheet of 600 grit wet and dry silicon carbide paper and a generator bearing on a stick rolling back and forth across the paper on the plastic disk for about 40 minutes.

It yielded lousy resolution of 350 lines, lousy contrast. An initially dreadful thing to set up and try to use, I despaired of ever getting the it right and justifying my thus far wasted time.

Things slowly improved in increments from there. Some massage had to be done on the clip, like flip the image and mask off the vignette on the right hand side.

The clip is of Kim Bettenay singing his song "The Sock On Her Front Door", which features on his CD album "Strange Days".

http://www.youtube.com/watch?v=zBvAmbxMCA0

Peering into the guts of an Agus35
 

Given that I have let the innards of a Letus35 see the light of day it is probably fair that I should let people have a look at what I have been cobbling together.

Apologies to Agus Casse. I have not kept it as simple as it could have been but I did try.

With the exception of the prism block itself and its relativity to the groundglass outer rim, construction errors of up to 5mm in some places can still be tolerated.

http://www.youtube.com/watch?v=CnweOEEqlRY

Is there a wrong way to mount vibrating motor?
 

Is there a wrong way to mount a vibrating motor? I've made a mount from a plastic card for a Nikon F3 Type D. Because there wasnt enough room to mount the motor vertically, I attached it horizontally to the base of the focus screen. Looking through the LCD I can't see an appreciable difference in the grain fuzziness unlike a rotating ground glass.

http://www.flickr.com/photos/84946364@N00/458075232/

And are these supposed to be loud? Thanks for reading ...

Update: Used the Type D's tab as an anchor for the motor to mount vertically. But I still don't see the effect. Maybe the tube is absorbing too much of the vibration? Wish there was more space in this tube.

Your arrangement can not work for the following reasons.

The vibrator motor movement is parallel to the lens centre axis.

A groundglass movement must be at 90dgrees across the centre axis to deresolve groundglass texture (grain).

The cut down plastic card does not appear to allow movement at 90degrees across the centre axis only parallel along it.

The cut down plastic card is a hard acoustically live plastic and the air space inside the tube will help amplify the sound much as a speaker cone and air enclosure does so what you actually have is a fairly efficient acoustic driver.

Assuming that everything is changed to move in the correct direction, what may also be against your combination of components is the relatively heavy mass of the focus screen versus the eccentric mass within the small motor.

The movement may not be enough to disappear the groundglass texture completely.

To allow movement across the centre axis but support the groundglass on the focal plane in a self-centering rest position, Quyen Le uses three pillars with flexible attachment points for his Letus35.

The system uses no control linkages to form the orbital excursion path which in its normal orientation becomes elliptoid, not truly circular.

The cinedof movement employs four more-or-less quarter-elliptical spring/control linkages to support a groundglass screen in a controlled movement across the lens centre axis.

The system uses the four linkages to provide a self-centering support for the groundglass and are intended to form the excursion path into a circular orbital motion.

Wow!
 

Thanks Bob! I'm still trying to digest it. But I think I understand that the motor has to be laid on the same plane as the focus screen (vertical in my case) and center. The idea being to move the small grains in the screen in small vertical circles like when someone pans sand through a sieve (only a sieve is used horizontal). In this case, the holder shouldn't be too rigid or well attached to the tube body to allow movement. This is going to be a challenge.

My next hare brained attempt ...
http://www.flickr.com/photos/84946364@N00/458381455/
http://www.flickr.com/photos/84946364@N00/458381459/

I recently exchanged messages with a video enthusiast at Youtube who linked me to a pic of his own home-made adaptor, an affair which used a frosted CD-R and appeared to constructed of pillar bolts and plywood panels.

It has to be the meanest looking machine that ever drew breath. But before one judged harshly, the foundation of the design included ability for a spring loaded, three-axis backfocus adjustment, in general the principle I followed.

Agus Casse's vision of 35mm adaptors for the masses lives on and people have a lot of fun doing it purely and simply.

Here's some web addresses to some dated and useless information.


http://putstuff.putfile.com/87145/6797357

http://putstuff.putfile.com/87147/8689395

http://putstuff.putfile.com/87148/6909524

http://putstuff.putfile.com/87149/9241206

http://putstuff.putfile.com/87151/8192538

Thanks for these, Bob.

Two of the files seem to be the same, however. The first one
http://putstuff.putfile.com/87145/6797357

and the 4th:
http://putstuff.putfile.com/87149/9241206

are both "AGU35APVNEMOTORMOUNT.pdf"

There seems to be a fashionable phrase around "my bad". I've oft times marched to the beat of my own drum so it becomes "my incompetence". Either way, apologies for duplicating the file - too much haste, will try to find the missing one.

About time to kick the original thread back upstairs where it belongs.

I went along to the product demonstation at Curtin Univeristy hosted by Tino Liberatore (not Tony as previously incorrectly mentioned by me) from P+S Technik and Steve Rice, local film maker.

Screened in the cinema for the session at FTI in Fremantle, was a demo clip for the JVC GY-HD100/Mini35 combination, shot by Steve the previous weekend.

I went along to the shoot at "The Rock" nightclub in Northbridge, Perth to take some shadow of the shoot.

I used a Sony HVR-Z1P with AGUS35 on front. It is not a head-to-head test against the MINI35 as I used an entirely different lens set and had to stay out of the way of the main camera.

Here it is posted for interest of builders.

http://www.youtube.com/watch?v=Cu46tmYmRY0

Optics used were :-

Nikon f1.4 85mm
Nikon f4 12mm - 24mm zoom
Peleng f3.5 8mm fisheye

Zoom movement in the early portion of the clip was compositional adjustment in the relay stage by camcorder zoom, not the Nikon 12mm- 24mm.

The Youtube clip is a bit more gloomy than the actual footage. One day I'll learn to get the dark art of Youtube posting right.

Rob, I've been reading hundreds of posts and dozens of threads, but I can't seem to find a complete guide on doing a 35mm Adapter. I am willing to do one myself, but can't get to decide what kind of configuration would be the best.
On your opinion, will a rotating or a vibrating GG will give best results? What kind of GG is the best? I will be using a Sony Pd150. Do you think I will need an achromat?
I don't want to bother. If there's a comprised guide on the best configuration of a 35 mm adapter, that would do for me.
Thank you in advance!

I'll answer for Rob, if he doesn't get to you. You will need an achromat. I have the VX2000, and it needs one.

Redrockmicro.com has a full set of plans for a spinning adapter. You can modify from there. I built my first adapter using the plans as a guide.

I also now have the Letus35a, which is as close as you can get to a self built, while having someone else do it. It has both a condenser and an achromat, works great with the Vx2000, my FX1, and HV20, the latter two maybe requiring, for optimum performance a little stronger achromat, or an extension tube to allow zooming.