Sheldon,


Please save me from going through the almost 50 pages of this thread.

Where is the latest version of your 35mm adapter?

What camera are you adapting for the add-on?

What are the limitations your adapter has, like F loss, aberrations, maximum F before seeing any lens element (if that is the case), etc.?

Have you tried or do you think it would work in HDV cameras?

Hi,

I'm using the *original* agus35 design. I wrote a quick tutorial to get you started.

All I did was use on of these: http://cgi.ebay.com/58mm-45X-Wide-Angle-Lens-For-Sony-DSC-F828-DSC-F717-V3_W 0QQitemZ260031542220QQihZ016QQcategoryZ116190QQssPageNameZWDVWQQrdZ1QQcmdZVi ewItem

Materials:
1. cd-rom motor (with the plastic mount)
2. 6 x 6 x 4 project box - can be any side
3. 9 nuts and 3 hex screws that the nuts fit onto
4. Grounded clear cd
5. On/off switch
6. Two sets of red/black wires (3-5 inches each)
7. battery box for 2 AAA battereis
8. Lens mount (I suggest Nikon- you can find Nikon lens mounts on ebay or at a photo repair shop)


Directions:
1. Drill two holes between 50-60mm diameter on the front and back of the box
2. Mount the cd-rom motor on the side OPPOSITE the side you want to put your lens mount.
3. The cd-rom motor should be in a plastic mount that has three screw holes.
Drill three small hols in the box, and use the screw holes in the
plastic motor mount to mount the motor to the box.
4. Epoxy the lens mount to the other end. Find the focal plane distance of the mount. For the nikon mount, its 46.5 mm.
5. Put a disc on the motor, and adjust the distance from the lip of the mount till the DISC is 46.5mm (or whatever you mnount's distaance) from the
lens mount's lip.
6. Solder the motor to the on/off switch, and solder the on/off switch
to the battery box using the wires. Mount all of these wherever is most
conventient-- you'll need to drill a hole to mount the on/off switch.
7. Sand down the clear cd with a cheap sander and 1000 grit sandpaper. Only
sand down one side.
8. Plop the cd on the motor, with the ground side facing the lens.
9. Put your lens on the box, and put the macro on the camera. Turn on the
motor, and connect your camera to a TV to help you adjust. Find your correct zoom/focus and you'll be done... construct your DIY mount off these distances.

I haven't tried mine on an HD cam yet. I still love the look of the dvx.
As for stoppage-- I haven't measured it yet- but if you look at this footage, http://www.schtm.com/cheap35/cheap35.html - it was taken on a cheap F3.5 50mm Nikon lens wide open in my dark room at night. DVX was set to wide open as well. I think my MF number on the dvx is around 35 and the zoom is around 72-- though I'll have to dobule check when I get home.

Sheldon,

The nivea cream leaves a fine layer, not unlike microwax on the CD. Some say it helps with diffusion and gets rid of the hotspot.

Sheldon.

Tis a good thing you are keeping the original thread alive with original building.

From viewing the image I make the following observation.

You have a brightness falloff to the corners and left. You will have this from a f3.5 lens so I would anticipate you should get a full frame with a f1.8 lens. You might however just pick up some remaining on the left side of the image as viewed.

If you have any zoom-in range left on your camera, this should take care of it.

This suggests that your SLR lens centre is slightly off to about 0.5 to 1mm low and about 1.5 to 2mm left relative to the camcorder centre axis as viewed from camcorder rear towards the groundglass, or the camera optical centre axis is slightly skewed or a combination of offcentre and skew.

Please don't take this comment as a criticism. Compared to my own efforts, you have it pretty well nailed. Because of the amount of zoom-in used, it takes very little to put the centre off, in my case, pulling up the seat belt on my assembly when taking it out in the car for a test is enough.

My own device has that amount of variation there always due to the flexing in the plastic casework and there being a chain of four removable joints along the optical axis, plus in my case three more for the prism path.

If you are fastidious about centres and your camcorder CCD image centre is the same as the camcorder's own lens centre axis, (NOTE: amazingly a lot of them are not) it is helpful to set up the camcorder mount and macro first on the second version you build because you know where it has to go.

Make sure the camcorder front and front face of the adaptor case are as perfectly parallel as you can get them.

Macro is best fixed directly to the camcorder for best centering. Once you have the rear mounting set up and secure, take off the camcorder then drill a small 1mm or 1/16th inch pilot hole in the case where the centre of where the SLR lens mount is to go.

Focus up and view this hole through your camcorder. File the hole out wider in the direction towards where the centre should be if it looks a bit off to one edge or another.

When it is centred, then measure out to your lens mount screw centres, fit the lens mount then mark out the clearance hole and go from there.

Within reason, centres are probably not the critical issue with groundglass relay as much as they would be for relaying the aerial image (groundglass removed) which I do for really long lenses.

As I have said before, welcome to the obsession. Go out and use what you have and become fluent with it before you go on to making any improvements. This helps you from heading into any dead-ends.

Bob,

Thanks for the advice; I'll try my best to apply all of it-- I'm trying to get in production ready for two short films I'm making. BTW, what's the quickest way to make an adjustable rod clamp?

Thanks,
Sheldon

Adjustable rod clamp? Got me on that one. I assume by rod you mean, of the lens hood and matte box Cavision style of arrangement.

I have another thread here relating to rods because I have need of knowlege on this question.

For different diameter rods, I guess you would need to have a Vee shaped channel across a piece of metal, at the end, a centre slot along the centre of that piece of metal and inside that another thin piece of metal with another Vee shape cut across that.

There would need to be a tail cut on the thin piece, outboard of the main metal piece, a sort of double "L" shape so a threaded hole in the main piece can carry a screw or a bolt which comes right through and presses against the tail of the thin piece to force it to close on the rod like an anvil type secateur pruner. This would look like a cross ebtween a clothes peg and pruner. The use of a thin pieice in a central slot would keep the clamping pressure centred and not cause the rod to tilt sideways.

Another way would be to drill a hole across at the end of of the piece intended to be the clamp, make the hole the size of the largest rod to be used, drill and tap a bolt hole so a bolt or screw can be screwed down on to the rod. For smaller sizes a sleeve would need to be used for each size to reduce the hole diameter down.

On that discussion page, a suggestion was made for my situation where I have used thick material. To increase the ability of the metal to bend where needed, several holes and "Tee" shaped slots were suggested. This method only applies to a fixed rod size. I guess if sleeves were made to be a really snug fit, this clamping arrangment could work for several rods sizes.

Seeyyumeeyah :-

http://www.dvinfo.net/conf/showthread.php?t=76241

While I am playing around putting links on the page, here's another one which might be of interest :-

http://www.screenwest.com.au/index.cfm?objectid=F727A6D0-65BF-EBC1-2021352CBF7131F1&navid=9CD848AD-C09F-1F3C-C8B2FDD4B037EF9C

Out of curiousity, has anyone tried a 16:9 anamorphic lens on front of a relay device which is attached to a 16:9 format camcorder?

As for the PD150, the Century Optics 16:9 works on front of a 28mm f1.8 Sigma for Nikon Mount and on front of a 50mm f1.8 Nikon for a DSLR or motion picture frame.

Rescaling the resulting image in PP2 yields a watchable sort of cinemascope but not outstanding image to DVD-Video.

I don't think I would be going out of my way to make a small or feature project with this method but it might be a valid method for creating the effect of one as a short segment in another conventional video project.

I have had a go at posting an Agus35 test which is comprised of direct-to-camera 16:9 footage to FX1 and Agus35 4:3 footage to PD150 fr the low light performance shot in low light conditions at a live gig.

It is on YouTube as a .flv file as advised on this forum. I don't know how well it has gone. The last postings I put there weren't remarkable for resolution.

As the audio on my download computer is somewhat deceased I can't vouch for how the sound transferred. It wasn't all that good, - room ambience.

It should be findable at this address :-

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

FOOTNOTE:

Doesn't work. I think I might have broken YouTube. It might just be taking time so might try again later.

It is on YouTube as a .flv file as advised on this forum. I don't know how well it has gone. The last postings I put there weren't remarkable for resolution.

As the audio on my download computer is somewhat deceased I can't vouch for how the sound transferred. It wasn't all that good, - room ambience.

It should be findable at this address :-

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

FOOTNOTE:

Doesn't work. I think I might have broken YouTube. It might just be taking time so might try again later.

What's the name of the video?

Is there any way to see a full or better quality fragment?

I have had another shot at putting it up again, this time the address is :-

http://www.youtube.com/watch?v=zgZaynJD3_I

I'm not sure how this one is going. It has been sitting dead for a long time the way the first one did.

I have tried to export a higher definition H264 file for posting elsewhere but the software does not get on with PP2 and creates a file which is visible only in the bottom right hand corner of the available frame and hugely enlarged.

It may be something to do with Service Pack 4 being needed, all in all a frustrating business.


FOOTNOTE:

This one seems to have taken root but the images are very blurry.

Nice video Bob.
Shot this Saturday in 2 hrs: http://www.schtm.com/ghosts.html

A poor quality clip from the Peleng lens to Agus35 can be found at YouTube at the following address :-

http://www.youtube.com/watch?v=8t5EKQW0mB0

I think I may have found a pure and unsullied upload path to a file sharing site which can shake hands with my old online computer through the 300metre overhead copper pair landline which feeds my premises and exacts financial tribute for its efforts.

No guarantees as to how the download works as I cannot afford to bring it back down to look at it.

It is a 30mb .wmv file. I have kept the frame rate to half in order to preserve some resolution. It is an assembly of some lens tests, 12 - 24mm f4 Nikon digital SLR zoom on wide, 14mm Sigma f2.8, 50 Nikon f1.8, 85mm Nikon f1.8.

The subject is the Armadale retail dragstrip on Friday arvo markets day.

You will observe that there is some edge falloff from the prism path on left and on right from the lens mount being incorrectly centred. The zoom was pulled back a little in attempt to get better resolution.

The TV safe area is fine but underscan shows the falloff.

This specimen of my experiments is covered with drillholes, patchups and other mutilations and is inclined to move off true during heavy handling.

Optical path is SLR lens >> AO5 groundglass non-backpolished Ohara disk, CD-R size, at 1500 rpm >> 2 x prism >> Century Optics 4+ achromatic dioptre, Sony HDR-FX1 camcorder at about 50mm zoom-in, shutter 1/50th sec, 0db video gain and SLR lens apertures set to enable as close to f5.6 camcorder iris setting as possible without causing groundglass artifacts, manual whitebalance to Lemac Chart ( = grey card). Illumination conditions, bright daylight, facing south-southwest, then north-northeast. Time mid afternoon in southern hemisphere late spring.

The address for download follows :-

http://www.filefactory.com/file/fcebfe/

Here's hoping it works.

FOOTNOTE TO ABOVE:

Filefactory itself is a free service. My ramblings above might be misleading.

Do somone know how the "diy macro" in the redrock m2 guide is made?
Cant find any information about it.

thanks
daniel

Daniel.

Chris Hurd has recently put up a link to a dvinfo archive on the Redrock before it became Redrock. Might be worth a look. I dont recall the home made macro myself.

The link :-

http://www.dvinfo.net/conf/forumdisplay.php?f=81

thanks i read it before.
On the first posts the "creator" of the redrock m2 wants to tell the trick than on the other hand he wants $$$ for the tip or to buy the whole guide. I know he spent some time for that simple trick but i dont want to waste my money on every bit of information that should be free on these DIY forums.

>>>I found the trick on other sites from macrophotography. Its very simple.
Get a cheap binocular 7x50 with 50-70mm front lens diameter (depends on your camcorder lens). Take out the frontlenses from that binocular (these are achromats and mostly coated). Only one Achromat should have +6. If you stack them you reach that +10-12 for use with the HVX200 or Sony HDV.

If you get a old Zeiss binocular from ebay and put the lenses together you should get the same quality as the overprized century optic achromats.

best regards
Daniel

Daniel.

If you have read the like of it before then please ignore the following.

An earlier version (non-flip) of my plumber's PVC pipe flavour of Agus35 used a set of optics from a generic telescope eyepiece I believe to be out of China.

I reversed the orientation of the lens set relative to the camera view, mounted the optics in a new tube with a 58mm filter thread on the end and this worked fine.

It caused a very close couple to the camcorder and front of lens to GG distance was between 12mm and 18mm. The best position between these two had to be chosen to avoid barrel distortion or pincushion distortion.

The camcorder zoom had to be right in.

The lens set was unbranded and sold as a fit for Tasco telescopes. It was described as a 50mm 2 inch eyepiece and the only part number to be found on the pack was SW5042.

The only motion clip to be found on www.dvinfo.net/media/hart as "agusdemo.mov" was shot on a PD150 using this arrangement. If you don't want to wait for the .mov file to download, there are frame grabs from this footage as filenames "mtatk2f1.JPG" or similar.

The image area was about 24mm x 18mm. There was a bit of brightness falloff into the corners.

I moved on to a flip version because of practical difficulties of using cameras upside down or having to carry an extra monitor around.

A bit more fisheye footage of cityscapes can be found at this address.


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


Conditions were bright outdoors 3pm clear skies. I neglected to keep notes as humble public begain to look anxious at some locations so I kept moving along.

My version of the AGUS35 was described to me on the day as "that looks like the bastid issue of a multinova out of a tommygun. What do you use it for."

Also, the DeHavilland Tiger Moth aircraft is now 75 years of age. There is a clip oflong camera footage shot last Sunday at Murrayfield, Western Australia.

It was shot on theAGUS35 in aerial image mode, that is, no groundglass, simply used as a direct adaptor for a long lens onto the Sony camcorder. The lens is a Sigma f4-6.3 50mm - 500mm zoom. It works fine with th4 groundglass but better without it.

The clip is here :-

http://www.youtube.com/watch?v=v8f6Y3u1yYQ

nice stuff Bob!

Redrock really are fast these days. Ordered the M2 yesterday, it shipped today. i asked if there was any way I could get it quicker and a nice lady said no problem she would walk it through production the next day. She did, it's on it's way and I will get it Thursday.

Will let you know my thoughts!

new 35mm adapter..., WDR35 italian
http://www.wdr35.com/
370€

Looks bulky. Any footage or large grabs?

A DivX file of 12Mb of the Peleng fisheye footage can be downloaded at this address.

http://www.filefactory.com/file/c6a42d/

Just a short note to shove this thread back up to thetop of the heap for a while. Also, the Peleng footage referred to above is due to time-out from filefactory in the next few days.

bob, i sold my letus in the end. i hope the buyer makes it work better than me!

Last night, I got to cast my greasy fingerprints and stray DNA all over a P+S Technik Mini35 JVC HD100 model which has immigrated to W.A. and is believed to be the only known specimen in the state.

What a change it is to be able to offer a camera up to precise mounts and lens fittings and have them go on without obfuscation and my reversion to the red mist and foul language.

The thing works, no argument about that. Except for a bit of misunderstanding which comes from my practice of momentarily autofocussing a PD150 or FX1 to get initial relay focus, I found it simple to manage. The HD100 of course is direct relay.

The objective lens mount for Nikons is precise, locks the lens in place and best of all, no back focus of the Nikon lens mount is needed.

It helps to have built and have spent some hours using a home-made as once the basic operating methods have become instinctual, everything on the MINI35 falls into place where you expect it to be including the offset.

I am confident that any competent camerman who has constructed and made a lot of use of their own Agus35 or similar emulation would be able to step into a Mini35 with all the ease of putting on an Armani jacket.

It is patent that once set up correctly, the Mini35 will function solidly, not drift off-axis, spoil the sound or display any of the other vices my own home-made gadget will have me on constant and distracting vigilence for. The motor is very quiet and no vibration can be felt.

It uses the camcorder batteries so no worries over remembering to bring spare torch batteries.

The construction and finish are excellent, a welcome change from hacksaw marks in PVC sewer pipe, dags of blueglue on joints and brushmarks in blackboard paint.

Best of all, it doesn't creak or groan when hand-held. It is smaller and not anywhere near as heavy as I expected it to be.

The owner had the good sense to buy the additional front extension arms with handgrips on them.

On the shoulder, with these, I would feel confident in being able to stay on subject with up to an 85mm prime lens hand-held, with a focus puller of course and not be crippled after an hour of using it.

Best practice of course will be tripod or other stable camera supports.

I hope to be tagging along when furthur tests are done and the first project is undertaken with it.

In meantime I shall have to plug along with Agus's best as the real thing is well over my available and justifiable budget but at least I know now what to aspire to.

Bob:

We talked about achromats in another thread I started. I'm still awaiting delivery of my 72mm achromat from Cinavete... hoping that will improve the footage I get on the FX1 Micro35 DIY project I built. Will advise you what kind of luck that has brought. Hope to get where you have gotten already, at a minimum.

Chris.

I think that you will find that you shall get there. Whilst the 58mm lens will work, things can only get better if you are shooting through a wider one of equal quality.

There may be a sweeter spot in terms of how close to the camera the GG has to come versus how far the zoom goes in.

I cannot over-emphasise how important having the centre axes of both the camcorder/achromat and the SLR correct and all the faces parallel is.

If the centres are off, whilst you will get adequate coverage of the GG with your SLR lens's projected image, some interesting assymentic distortional things happen if you choose to use ultra-wides like 14mm or Peleng 8mm.

You can of course cheat a little by applying a bit of correcting pressure to skew the axis before you tighten the camera and adaptor to rods or other bracework. You risk edge softness with the wide lenses by doing this.

DAY 1 OF RED BULL AIR RACE in Perth W.A.

Amazing stuff. I am covering it as best I can for my own aviation archive which is another story I won't go into for the moment.

I am using the Agus35 with groundglass removed for the long lens and found it works this way just fine for the fisheye lens as well with thecamcorder zoom in all the way and the Peleng lens wide-open.

You can actually get away with f4 but I am skewing the axis slightly to bring the flat horizon down to the lower third of the image frame for better, more natural composition. With f4, this offset picks up the iris in one corner on underscan.

There were two helicopters doing airbourne coverage. One of them flew the actual competition course. It had a gyrosphere?? hanging off the front. The pilot of the helicopter wasn't bad at what he does either.

I couldn't get media accreditation so I had to be satisfied with looking in longingly from outside of a link mesh fence.

I tried for some 8mm shots of the take-offs from head-on outside of the fence. The rate of climb and angle of these aircraft is mindblowing. Fisheyes for ground-to-airs of aircraft are a bit difficult. The aircraft has to be really big or really close to fill the frame.

The redbulls are small aircraft so we are talking blowflies visually.

The long lens wll come out tomorrow for some more head-ons and the landings which are equally spectacular. Sunday will be more long lens of the actual competition and the air displays.

There were four other FX1/Z1P operators passed by. I lost a few opportunties when people wanted to know what was on front of the camera.

Nearly all serious cameramen who stopped by knew exactly what it was and what it was for, so it seems there is a lot of general knowledge out there now about adaptors.

Chris.

I think that you will find that you shall get there. Whilst the 58mm lens will work, things can only get better if you are shooting through a wider one of equal quality.

There may be a sweeter spot in terms of how close to the camera the GG has to come versus how far the zoom goes in.

I cannot over-emphasise how important having the centre axes of both the camcorder/achromat and the SLR correct and all the faces parallel is.

If the centres are off, whilst you will get adequate coverage of the GG with your SLR lens's projected image, some interesting assymentic distortional things happen if you choose to use ultra-wides like 14mm or Peleng 8mm.

You can of course cheat a little by applying a bit of correcting pressure to skew the axis before you tighten the camera and adaptor to rods or other bracework. You risk edge softness with the wide lenses by doing this.

After the first version with a $5.00 Radio project box, I recognize I have to be a bit more exacting. So I've already purchase a new box, and will probably change my design a bit. I won't do that until the achromat arrives.

In the meantime, with what I have got, I am learning more about the alignment issues. Nothing really great coming out of the +10 close up lens, so the achromat is my next big step. Then, I should no better what to blame on my poor alignments in the first build.

Other issue is I am using some old Pentax K mounts lenses as the prime lenses, using the glued on rear lens cap technique.. May look at ordering adapters from Redrock before I do rebuild...

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.

Julius.

I can't speak for the Canon lens with authority as I have not used it. Comments on the web favour this lens in terms of quality for the task it is intended, a high quality close-up lens for still-cameras.

I did find comment on one website that the lens was in effect 4+ lens or thereabouts.

If it is a 4+, for the 24mm x 18mm 35mm movie frame, I don't think it will be powerful enough. The camera on full zoom may not frame tight enough and you will likely get an image with a hot spot because the frame may be in the ballpark of 40mm x 30mm but I am really only guessing here.

In my original testing for the PD150 which is optically similar to the VX2000, I used an inexpensive three lens in one pack set. This was a 1+,2+ 4+ and stacked you got 7+.

The stack was the only magnification power that worked for my setup.This stack of lenses however causes a real problem with chromatic aberration because they are only single element optics.

The front element of the VX2000/PD150 lens is 52mm diameter. I used the optics out of a 50mm 2" telescope eyepiece which had a diameter of 44mm which just worked with the camera at about 80% zoomed in but these don't come cheap either.

If you can't find a cheaper 7+ acromatic dioptre which will mount to the 58mm filter tread, you may find one with a smaller diameter. As long as it is no smaller than the 44mm I used, it may be okay with a step-up ring to the 58mm.

There is a chance however that there may be a ring shaped defect out towards the corners of the image as the telescope lens set does this with the FX1 which uses more of the groundglass image width than the PD150.

I am not a lens technician so my thoughts on the matter have no validity beyond what lenses I have offered up to my camera and find worked or not.

A 5+ may get you coverage of the 36mm x 24mm??? still-image film camera frame. This size is favoured by the builders of static grounglass devices as the grain or texture of the groundglass is smaller in proportion to the size of the image so resolution is better and the grain artifact is less evident.

At this groundglass image size, builders start talking of hot spots or edge falloff and condenser lenses which even out the lighting across the frame.

I'm sorry I cannot help you with this beyond what I have found is workable for me.

Iv'e done a bit of hunting around and it seems the Century Optics +7 may be the only game in town though the beta 72mm +10 achromatic mentioned on this site looks interesting.

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.


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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/theeleventhsoldier/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.

Bob:

We talked about achromats in another thread I started. I'm still awaiting delivery of my 72mm achromat from Cinavete... hoping that will improve the footage I get on the FX1 Micro35 DIY project I built. Will advise you what kind of luck that has brought. Hope to get where you have gotten already, at a minimum.

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.