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-   -   Homemade 35mm Adapter (https://www.dvinfo.net/forum/alternative-imaging-methods/17195-homemade-35mm-adapter.html)

Agus Casse March 16th, 2006 02:40 PM

Thanks Bob, you are my hero to keep this thread alive... actually the proyect is not really dead, the problem is that i cant find the right components to make a new and improved version. Works have been a bitch, but i think i can find the time to get back to the proyect in a couple of months.

Jim Lafferty, actually there is a old thread, which a guy put a razor and make the adaptor vibrating.., and actually my first version was using vibrations. also remember that my adaptor uses diopers, and achromats.


Quyen Le, i have been reading a lot of post about new adaptors, and i have received a lot of emails if i will make a commercial version, thats is why i am talking with a industrial designer, to find a way to make this thing cheap and with milimetric presicion.



see you guys soon...

Jim Lafferty March 16th, 2006 04:01 PM

Ah... I thought you'd just used the credit card magnifier or the glass from a reading magnifier and not an actual achromat. I guess in trying to condense the history, I'm looking at the peaks and not all the smaller developments on the way. I'm pretty sure it was Brett who came to the table with much of the achromat research we all benefited by, and that's why I put his name there.

Bob Hart March 21st, 2006 12:11 PM

Resolution Tests with an AGUS35 style device on a Sony HDRFX1 PAL.

The image yield occurred with the following path.

Test Chart >> SLR lenses at f1.8 >> AO5 groundglass (backpolished slightly) >> two prisms >> Century Optics 7+ achromatic dioptre >> HDRFX1 camcorder.

Conditions were adequate artificial lighting of the test card. Camera fixed on a sturdy tripod. The frame taken from the groundglass is 16:9 and about 26mm wide.

Today, I looked up the resolution scale printed on the back of a Lemac test card. I shot some lens tests with this card about two months ago. I had misinterpreted what these resolution indicators mean and wrongly assumed they all were invalid for assessing video.

The resolution of the FX1 LCD flipout screen may not be that of the camera system itself. In the screen, all but the "A" and "F" indicator patterns were visible. Whether the camera is actually seeing the individual lines in the finest visible "B" and "G" patterns or there is a moire interaction happening I don't know. But it seems from the LCD screen that the pattern is being detected.

For a moire interaction to occur it would seem that the CCDs of the camera should actually be seeing the fine patterns of individual lines. However it might not be necessary for the lines on the card to be seen at correct resolution for a moire pattern to be generated. It might happily occur if every second or third line was seen by the camera CCD for moire to occur. I simply don't know enough about the subject to make assured comment. I have not yet been able to get access to a high definition monitor to look closer at the recorded image.

That aside, if the camera CCDs are seeing every line in the "B" and "G" resolution indicator patterns, then according to the card, horizontal resolution is up to 864 lines and vertical resolution is up to 486 lines.

This hints at a better result than my guess of 700 lines from the EIA1956 test pattern from earlier tests into a PD150. The PD150 is apparently limited to 530 lines and that is where the separation of the four tapered lines ended. But there remained hints of the tapered line pattern outward into the 700 zone to about 710.

According to the card, the higher resolution "A" and "F" indicator patterns will not resolve on HDTV anyway. These are 1920 lines and 1080 lines respectively.

If my fairly rough and ready appliance with its home-made groundglass is truthfully yielding these results, then better results can be anticipated from the more thoroughly designed appliances with better groundglasses.

Bob Hart March 22nd, 2006 01:45 AM

A hint for anyone building an AGUS out of plumbers pipe and pipe caps.

The f1.8 lenses give you a nice wide area of light across the groundglass, larger than the 25mm or so the 56mm hypotenuse prisms will allow. When setting up the centres on the camcorder mount and the front lens mount to make the holes in the pipe caps, a little laziness may creep in and an adjustment to the front cap (ie., a remake of a new cap = lots of work and a wasted cap) one tends to leave the front cap as-is if the most vignette prone lens in the arsenal works okay.

You set up the backfocus across the entire image, by aligning the lens mount true to the rear camera mount, correct the backfocus again then fine tune it with the three adjustment screws while sighting on a infinity target, fuss around until all the interactive effects have cancelled out and are then well pleased with this beatific smile on your face.

Then you go and do a real-world test and find there's a soft edge or a corner. It's consistent across the entire range of lenses but more aggravated with the sides and turns up when the lens is focussed on something midway in the range. You check the device. All the glue locks are intact and nothing has moved. You didn't leave it in the sun to cook and nothing has bent or gone soft.

Then the dim realisation begins to pall. You stop the lens right down to get the darkest vignette and there it is. The lens is off-centre relative to the camera view, something the wide lenses will not accommodate, especially on closer objects.

On reflection, I would have saved myself a lot of time and effort and sacrificed pipe caps if I had made a facility for lateral adjustment of the lens mount position along the radius of the pipe cap, a simple slide and clamp arrangement and used the rotation of the cap itself on the image tube to provide the second direction of adjustment.

There is no room for unthoroughness and expediency in this business.


Another caution. If using small self-tapping screws to fasten into the PVC, take care not to screw them in fully home in one hasty journey to firmness. They generate enough heat to melt the plastic but also to cause a heat related stress rise where the head of the screw joins to the shank.

The plastic cools and sets on the screw threads. Later, you decide to dismantle, there is a gentle SNAP!! and the head comes off the screw. It has happened twice.

Grooved self-threading screws such as found in some players and videos, might be a better choice.

TEKs are no good as the drillbit on the end is too wide for plastic and will cut too much away for a secure fit.

Don't use the knurled screws which look like the threads are a sort of rasp or file to cut threads into the plastic. These will begin to strip the hole if fitted more than once as they are not intended to be unfastened.


Quyen.

If you are reading, I had a random thought about high definition resolution on your device. It might be worthwhile getting a few microscope slides from your nearest university medical faculty, high school or from a pathology service, a piece of aluminium cooking foil and some of Oscar Spiers wax formula.

I tried it wax between two disks but abandoned the idea because I was not able to control the thickness of the wax layer consistently around the whole disk. The image quality was by far the very best but the flicker was totally unacceptable = 1.5 f-stops.

Because your groundglass has a much much smaller movement than a spinning disk, consistency of the thickness across the groundglass should not be the same problem.

The problem would be locking the two glass panels together so that the wax and glass do not separate due to the vibration. The vibration and travel of the groundglass may be adversely effected by the extra weight and the wax composite panel of course will be vulnerable to effects of heat like any other wax gg. The lesser grain of the wax however may enable a smaller travel of the gg and make for a quieter device. - Just a thought.

Jamie Roberts March 24th, 2006 05:58 PM

Hi all

my project to make an agus35 is officially finished. Its as the original one is, I gave a 10x macro lens between the camera and the gg, I have mounted a 40mm plano convex lens between the gg and the 35mm lens (closer to the gg), gg is sanded plastic CD mounted on a cd walkman motor, and i am happily able to shoot in widescreen on my gs400 without any hotspots, lightloss around edges etc. The money thats gone into it is about $60 australian and the results in my opinion look great in terms of acheiving shallow dof.

these threads have been invaluable in helping a clumsy novice like me make such an effective bit of kit! thanks alot

jamie

Carl Jakobsson March 24th, 2006 07:16 PM

Jamie, I would like to see some footage. I also believe in sanded cds... :)

Dennis Wood March 24th, 2006 08:09 PM

Jamie, I'd love to see some PAL footage from your GS400 with the adapter. This is from my GS400 with my spinner (now sold):

http://www.filefactory.com/get/v3/f2...4268f3d5e956b9

The GG is 1.5mm optical acrylic, fine media blasted on a rotating jig (at 1000rpm).

Bob Hart March 24th, 2006 10:52 PM

Night Tests. AGUS35 to HDRFX1

For sake of some real-world testing, I went down to the local retail dragstrip and on into the city and shot some unassisted footage in the night. I stopped by the caryards in Vic Park on the way home. They are well lit and a cheap way of seeing how the system performs under good lighting. As usual, the roving security people give you a strange look and passing fitness walkers do likewise when they see the weird gadget on front.

The light loss of the system is most apparent on the cityscape.

The direct-to-camera images are bright enough for the overhead scud cloud to be just visible.

The light loss through the system is very noticeable, especially through one lens, the 12-24mm zoom which is f4. However, and this is weird, there was not the apparent two-stop increase in the brightness from the f1.8 lenses I expected to see. I can't work that one out at all.

From the relayed images, all you get is the pinpoints and dim window rows on the towers. Direct-to-camera picks up spill from streetlighting onto the sides of buildings. So for night footage of cityscapes, the relay system might better be abandoned in favour of direct-to-camera.

Another weird aspect is that I forgot to turn the disk on for the first two lenses and there is no groundglass texture to be seen.

The longer lenses perform better, mainly because any bright light sources such as signage occupy a larger portion of the image and are recognisable.

Under the bright lighting of the caryards all the lenses performed well. Except for the increase in brightness and better contrast, there was little discernable increase in apparent image sharpness between the relayed and direct-to-camera images.

Again, there was very little discernable difference between the f4 lens and the f1.8 lenses in this lighting environment. On a high definition display it likely will be a different story but I have no acccess to one.

I also shot one test with a single lens in a streetscape after light rain. The area was moderately lit. With the gain fixed to keep the blacks less noisy a pleasing and realistic image can be had.

I have tried to put motion files up on www.putfile.com but have not been able to download them to view them so have no idea if they are downloadable or not. Can somebody give me some advice on the best compression system for placing motion files there?


Jamie.

Congratulations on completing your project. Now may likely begin, the obsession of trying to make it that little bit better.

If you have a chance sometime, could you post a frame grab somehere. I'd be interested in seeing how the condenser performs in your arrangement.

For field of view without a condenser, my arrangement frames the 16:9 Lemac chart in a 25mm wide frame on the groundglass with a Nikon f1.8 SLR lens set at 1.0 metres from chart to groundglass.

Dennis Wood March 24th, 2006 11:34 PM

Bob, try http://www.savefile.com/ for uploading files.

For sample footage at full frame size, windows media 9 (MPEG4) is hard to beat. Encoding takes a long time, but at 3000Kbps, the quality is better than max bitrate MPEG2, IMO.

http://www.freefunfiles.com/software...encoder-9.html

For NTSC HQ anamorphic footage 16:9, I resize to 872x480 square pixels, and encode at 3000Kbps. That's about 17MB/minute. All of my uploads for adapter footage tests are done that way.

For NTSC lower quality anamorphic footage 16:9, I resize to 436x480 square pixels, and encode at 500Kbps.

Hope that helps. If you want a few .wme files email me. They can be loaded into the encoder and will have all the settings done for you. You just will need to change source and destination file locations.

Hope that helps. If you're on a Mac, H264 is the MPEG4 to use...and I can't help you :-)

Jamie Roberts March 25th, 2006 12:25 AM

i am going to do a little staged shoot tonite here at home using artificial lighting.

will put something up as soon as i have something.

cheers

jamie

Bob Hart March 25th, 2006 06:50 AM

First look on a high-definition plasma screen.

Today I took a FX1camera and a component patch lead across to our neighbouring Harvey-Norman and they graciously permitted me to playback tests in the high-definition realm.

I have to confess that despite my scepticism, the playback looked a lot better than I had expected.

The pitfalls of the home-made relay device soon became apparent.


Sharpness of the image.

The AO5 finished groundglass texture can deliver an image of adequate sharpness. Maintaining the sharpness of the image delivered to the groundglass is another matter.

Focus failed on two levels, the relay and prime lenses, both due to operator skill or lack of it. In a production environment, a high-definition monitor would be essential. Being short-sighted, I occasionally overlook soft-focus given that it is my natural normal vision state.

I also found that making lens changes often meant the camera focus ring was bumped. This needs to immobilised after relay focus is set as another participant at this site has already observed.

Light levels onto the groundglass also seem to have an effect. The camera's ND filters amd manual apertures have to be used more and with more precision. Some interactions occur between the prime lens aperture adjustments and the camera aperture adjustments which can add to or subtract from sharpness.

An image containing a strong large area backlight and a large area underlit foreground was almost impossible to resolve without visual artifacts from the groundglass disk appearing.

This was most apparent with a f4 12mm-24mm zoom which only leaves one f-stop of adjustment before the f5.6 rule is broken. If lens aperture was adjusted to reduce the overexposed area, artifacts appeared in this area. If the camera aperture was opened up, the artifacts moved to the underexposed area. The f1.8 lenses fared better but it is a fine tapdance trying to find the best combination of both aperture selections and the ND filter.

The scene was views along a roadway lined with thick forest under light 7/8ths overcast with patches of clear sky. A graduated ND filter might be the only way to resolve this image if it possible at all. It is certainly a scene I would avoid.

"Magic-hour" shots looked great, especially with light from behind camera, in the direct light or in open shade. The sharpest images were achieved in this circumstance. A one-stop manual under-exposure seemed to yield the best sharpness and colour rendition.

The colours of backlit foliage in the "bokeh" areas was an excellent effect, likewise at night, the various colours of lights when focus was moved from very close to on-subject with the 85mm and 105mm lenses.

Another effect on sharpness was observed and has been previously commented on. There were occasional slight momentary focus shifts due to end float on the disk motor allowing the groundglass to move off focus. There is only about 0.25mm in it but it is enough in the HD realm to spoil the image. Up until today, I thought I had eliminated the problem.

A possible solution might be to fix a large metal washer very close to the motor side of the groundglass with a large enough centre to surround the hub and using the magnetic piece found in some CD players which clamps the disk. The magnetic field may be enough to keep the motor armature back against its rearmost limit without adding the friction a home-made thrust bearing would.

The night footage seemed softer and flare in the relay images was more apparent as one would expect from the many extra pieces of glass in the path. Except for inferior contrast, there seemed to be less difference between the direct-to-camera images and the relayed images than during natural daylight.

There was one incident of chroma separation on the right side of the image as viewed. I attribute this to the prism path as it is not uniformly spread around the entire outer edge of the image. It showed where a bright tripod leg intruded into a darker area of the image which was also slightly out of focus.

The earlier tests which made apparent the misalignment of the groundglass and lens centres were woeful to see in the HD realm on a large screen.

I found I had some eye tiredness after 50 minutes of viewing. I experienced this eye tiredness to a lesser extent after watching "Star Wars Episode 2" and on a par with that I experienced after watching "Open Water" , both movies in a theatre.

Overall, I think one could make a low budget feature with this combination but it would require a stressful degree of close vigilence and avoidance of some lighting situations, notably, large untextured areas of overlit background and underlit foreground of more than two or three f-stops of difference.

There's a way to go yet with this project.

For now, the FX1 goes back to its own home with my fingerprints on it and it's back to the PD150 for a while.



Dennis.

Thanks for your hints. I'll give that a shot.

Jamie Roberts March 26th, 2006 03:38 AM

Hi all

heres a link to a short clip that i did up today that shows my agus35 adapter in action!

http://www.filefactory.com/get/f.php...3a59388db778dd

Inside stuff really didnt have enough light but i kind of liked the way it looks anyway. Outside clip at end is to show how it looks in good light.

Im not after perfection. I will definately use it for close up shots where i think it really comes in handy. I would like to now continue on im my efforts to actually make a decent little movie!

I can see how easy it would be for it to become a hobby in itself just working on improving a 35mm adapter but thats not me, unless some new simple idea comes along that a child could make (so I can!), i'll be content with this for now.

Jamie

Bob Hart March 26th, 2006 05:19 AM

Jamie.

You've done well it seems, going by the clip playback.

There's no more needed to be done for your purposes, beyond perhaps some fine adjustments, unless you want the convenience of a flipped image.

I observed no variable density flicker in any of the images so it seems you have the disk well sorted.

No evident endfloat of the spindle or misalignment of the disk on its hub is evident.

Interiors are as bright as I would expect them to be.

Corner to corner, the light intensity seems to be even, I guess the benefits of a condenser in the path at play here.

In the exteriors there is a hint that your disk might not be square-on to the focal plane or the camcorder centre axis might be slightly off, but it is usually the disk alignment itself which is usually more affecting to the image.

As I see it, the left edge of your disk may be about 1.5 mm rearwards and the top edge of the disk about 0.75mm rearwards, relative to the centre. This is really only wild guess as I am going by the soft areas in the backdrop of the hedge and the nearby roof eaves which seem off in the right and upper portions of the image as viewed.

This is however very much an assumption. It may be that the hedge is not square-on behind and the roof eaves in a genuinely out of focus area so don't take too much notice of this comment.

The interiors seem square-on as far as the disk alignment goes so you might be getting a bit of flex with the CD-R case if that is still what you are using.

A little circular piece of plywood fastened to the inside front of the CD-R case with screws and silicone sealastic to stiffen the front structure might be the way to go if flex is happening.

This is the beauty of Agus's original design, a result tantalisingly close to the P+S Technik benchmark for a miniscule fraction of the cost and well within reach of the budget and construction skills level of the enthusiast.

The one and only motion video file at www.dvinfo.net/media/hart was shot on a non-flip version ith a plastic disk. Feedback suggests preference for the image from this plastic disk compared to the image from the glass disks.

Jamie Roberts March 26th, 2006 04:43 PM

thanks for that Bob.

You are probaly on the money in terms of the disc being slightly out. I also actually used an ultra thin sanded plastic disc that i found in a spindle of dvd's. maybe its too thin and wobbles a little. it would be half the thickness of the std clear plastic cd's u get.I was hoping the thinner one would allow more light.

thanks also for the good idea about reinforcing the front of the housing.

Jamie

Bob Hart March 26th, 2006 10:07 PM

Jamie.

Your disk is running true so I would not mess with it. The DVD clear spacers are good. They are optically true and run true if they are the ones you can see a slight trace of the guide tracks on (looks a bit like opal against the light). This is the surface you sand or grind away at.

You may well have hit upon a good combination. The DVD spacers or split DVD disks seem to be made of a harder composition than the older CD-R spacers. The DVDs don't seem to dress as easily using the abrasives I use for the glass ones but when you get a successful one, they seem to be as good as the glass. They also run true because they are thin and can bend and the centrifugal force takes care of any runout in the hub.

The more aggressive sandpaper with fixed grit might be a good solution for homebuilders. Once the abrasion has started, then a dressing in a fluid abrasive might be viable for a finer finish.

I made one and the image was more filmlike than the glass but it got a circular scratch on it from a screw-end sticking through the motor mount. When I took it off the hub to dress it again, I furthur damaged it and I have not been able to successfully make one since to replace it and am back to glass which I know.


With your arrangement, if there is mis-alignment, it will be in the fixed position of the disk/motor/motor mount assembly. I am assuming in all this that your condenser and SLR lens are both correctly centred relative to each other.

How have you mounted your disk motor? Have you provided for any adjustment? If you have screwed it straight onto the rear cover of the CD-R case from the outside and have mounted the hub and disk on afterwards on the inside, there may be some flex going on there in the case. If that is what you have done, then a round piece of thin plywood, screwed onto the case surrounding the motor and three screws with the ends filed off flat so they don't puncture the plastic case, threaded through the plywood at the points of an imaginary triangle, each point about 25mm out from the centre, pushing against the plastic to bend it slightly when you screw them in, might distort the plastic of the case enough to give you that final trim adjustment. It would be a cheap and nasty fix which would drift over time as the plastic slumps.

A better method is to mount the motor on a plate and fix this plate to the case. I use three small gutter bolts fixed to the case with nuts, then a small stiff coil spring around each bolt, the motor mount plate sitting on those, then another nut and washer on top to screw down to press the mount plate forward or loosen off to release backward using the spring pressure. In your arrangement, you might need to fasten the bolts to the motor mount and have the adjusting nuts on the outside of the case where you can get at them, as you don't have the same workroom to fit them around the disk inside the case as I have with the pipe caps so you are limited to mounting and adjusting from the rear of the case. It is a better solution for adjustment in the field as you don't have to take a cover off like I do.

If you can get hold of or photocopy a Lemac chart with the four Siemens circles in the corners, these make an excellent back-focussing and alignment aid as you can adjust until all circles are the same sharpness.

Jamie Roberts March 27th, 2006 12:02 AM

Im afraid my motor is glued in well and truly with liquid nails!

One thing i am not 100% sure on and will check is whether the condenser is actually centred 100% to the slr lens and also whether the condenser is sitting on a slight angle to the gg. I dont know if the angle bit would matter much?

I have mounted the condenser in another cut back cdr housing top (like whats it mounted in now. I cut it right back so there is small lip and was able to push it in and upto the gg without interfering with the spinning etc. It actually a bit hard to check as when i push it in i can no longer see the gg except through the condenser. I know if ive pushed it in to far as the disc wont spin, so i pull it back to the disc spins fine and thats basicly my method. I will re fit it and pay closer attention to the whether the condenser is centred on the slr lens and whether there it is flush but offset from the gg.

Jamie

Bob Hart March 27th, 2006 12:15 AM

Dennis.

I've tried to upload a 50mb Quicktime H264 file to savefile.com but the machinery here sits and licks its tail without sending anything out. It has been a longstanding problem. Large .pdf files in which I wrote construction methods and which contained still images have the same problem.

I rang my provider who advised that my system (Windows Internet Explorer on W98SE will not handle such a large upload and that I need to use a FTP client?? The provider is not allowed to recommend any system over any other. Any recommendations or hints??

In the course of doing all this, I forgot to set the HDV to DV conversion to "on" in the camera menu but the footage captured anyway so I don't really know what is going on. The system is supposed to be "NOT" HDV capable.

Whatever? It writes a better DVD-Video disk because of it so something has been learned. The whatever it is takes heaps longer time to render or convert to mpeg4. You can also have it any way you like as long as it is stretched vertically so the file I have made was letterboxed so it presents correctly.

It might be easier to make some datadisks and send these by mail or camera tapes to people who have more knowing on computer things than I.

Bob Hart March 27th, 2006 12:40 AM

Jamie.

What you have there is yielding about 85% which should be adequate at a hobbyist level. I wouldn't mess with what you already have working for you as it may not come together quite as well next time. There are too many variables including the thin soft plastic case and there being no fine adjustments available.

For improvement into that 90% plus arena, I would favour a complete re-make so that you still get to enjoy the benefits of the original appliance.

I used PVC pipe caps and tube because the material is more robust and a tube enabled centres to be more accurately kept but the device remained nearly as simple as Agus's first.

Ben Gurvich has a project box version which works well. He is within a half-day drive of your patch but I will leave it to you to initiate contact to see if he is prepared to make his contact details available to you and advise if he actually has the device still with him. Ben visits this site so you should be able to get a blind email to him from here.

He is however quite busy in his fulltime work in commercial TV so may not be able to assist you.

His version I think was based on a design which I think was published by Jim Lafferty. It is robust and because it has flat surfaces everywhere is a lot easier to mark out and get centres for than a circular object. It is probably a better and more predictable project for a home-build from scratch than my own.

Bob Hart March 27th, 2006 05:59 AM

AGUS35 APVE TO SONY HDR-FX1 TESTS.

I was unable to get anything but small motion image files uploaded but there are four which are very truncated versions of originals and do not encompass a full lens range as the original longer clip did.

One of the clips No4 also includes aerial-image footage shot through a Sigma 50-500mm f4-f6.3 zoom.

The clips are all QUICKTIME H264, whatever magic that is. I faithfully followed advice and it worked, so thanks again Dennis for your input.

They won't play on my web computer but will play on the editing computer which I keep quarantined from this one.

Some of the shots were made before I re-centered the front lens mount so you will observe a fall-off to the left side in some shots. This is caused by the edge of frame being too close to the horizontal prism apex, a situation forced by the 28mm half-hypotenuse of the prisms I presently have fitted. I hope the larger prisms will fix this as I will have space to move the apex furthur to the left.

The web address which seems to work is :-

http://savefile.com/projects/338360

If anyone actually gets one of these downloads to play back I would appreciate the knowing.

Carl Jakobsson March 27th, 2006 12:56 PM

Thanks a lot for the interesting reading and viewing! The movies work fine on my Mac (Quicktime and VLC), haven't tried them on my pc though. But I suspect there's something wrong with the field order, it's most visible in the airplane and boat clips.

Bob Hart March 27th, 2006 08:15 PM

Carl.

Thank you for your feedback.

Field orders and compression settings, while I know of them, are a dark art I have yet to teach myself some competence in.

The original footage viewed on TV, copied over to a DVD video recorder or captured to computer, does not have those defects, so my mishandling of the computer will be the culprit.

Moises Crespo March 27th, 2006 09:34 PM

My35
 
My35 I accually scratched the macro filter right in the middle but check out the footage.. http://media.putfile.com/Sequence-1_...bit_DSL_stream
Thanks,moe52

Jamie Roberts March 27th, 2006 10:05 PM

As i cant leave things well alone! I am in the middle of rebuilding my adapter with a few minor adjustments.

I noticed that the condenser was sitting a bit higher then the slr lens and therefore out of line so i have pulled the condenser and re-glued it into a better position in its support frame so lines up better with slr lens.

I also noticed that the mount that the camcorder lens goes into wasnt sitting flush with the adapter ie was on an angle so therefore the camcorder wasnt facing gg directly. I have pulled that off and reglued it so its square on to the housing.

The very thin plastic disc i was using is splitting from the centre out. too thin im afraid but I found another plastic disc that already has a fine slightly 'sandblasted' look on one side. I want to preserve that side as I think it may be effective so I am sanding the smooth side with 600 sandpaper. Anyway in the next couple of days I will get a chance to put it all back together again and see what happens! Hoping that it dazzles me so I can leave the bloody thing alone!

Jamie

Bob Hart March 27th, 2006 10:23 PM

Jamie.

If you've got a plastic disk which does not flicker, treat it like gold, as such are quite rare. If you have a small electric soldering iron for electronic work, fire that up and burn a small hole through the plastic where the crack comes to an end, then trim the rolled up edge of melted plastic off with scraper or old style ribbed razor blade. The crack should travel no more. The scrapers and blades can be had from hardware or ceramic top electric stove retailers.

If you don't have an electric soldering iron, a piece of thick wire cooked up over a gas flame will do.

Aligning the camcorder is a good move because it puts the best area of gg image centre in the camera's image. Though perhaps not quite as critical as getting the SLR lens and condenser centred and their common centre axis exactly at right-angle to the groundglass, getting the camcorder itself lined up places you furthur into that elusive 90% quality zone.

Jamie Roberts March 28th, 2006 05:17 AM

Well i have it up and running but only had time for a quick test. will do some more tests on the weekend and post a link to some footage

The disc i tried with the sandblasted look on one side and me sanding it on the other wasnt that great im afraid. I currently have put a normal gg disc back in which works fine but will take your idea about the one with the little cracks and use my soldering iron to stop them going any further, and try and use it again. its is a rare one as I havent seen one this thin before. i must start hassling all my cd/dvd burning friends to keep all their clear discs. the last pack of dvd's i bought last week didnt even have one! Just paper protectors.

seeya

Jamie

Bob Hart March 28th, 2006 08:53 AM

Jamie.

You can get them anytime by scrounging failed DVD burns from the bin. You split these disks along the purple layer. The purple dye sticks to both halves but the purple side on the clear half is the bit you sand off. You can use the other half but that white printable label stuff is a sort of a latex and is impossible to get off without injuring the clear finish underneath.

There may be solvents which will clean the latex or purple dye off without injuring the plastic. As these disks are not intended to be broken open, be mindful that the dye may be poisonous.

Use gloves and long sleeves and if you wet sand, make sure you ditch the water in a safe place and do not risk cross-contamination of foodstuffs or utensils by using the kitchen sink or the utensils themselves. If you dry-sand, wear a good dust mask and do the job away fromwhere your nearest and dearest might be exposed to the substances.

It is hard to get the split started but once it starts they peel apart easily.

You can try to prise them apart with a sharp point, or try to start the split by dropping them on edge onto a hard surface. It seems to help to boil them first.

IF ANYONE KNOWS IF THE DYE LAYER IS INDEED DANGEROUSLY TOXIC, PLEASE FEEL FREE TO ADVISE.

Jamie Roberts March 28th, 2006 11:18 PM

Well i'll be buggered I didnt know that!!! thanks for that valuable bit of info Bob.

I have managed to shoot a little bit of video today outside to test the adapter and it ont eh cameras lcd screen it looked pretty good. will capture it tonight and post a link

Jamie

Carl Jakobsson March 29th, 2006 08:17 AM

I've only had flicker problems when the batteries or soldering was poor. When spinning with a portable cd-motor at 3V I get no flickering, even though the disc is far from perfectly sanded. On the other hand, the motor makes a lot of noise at 3V. I use external mics so that isn't really a problem.

Jamie Roberts March 29th, 2006 04:13 PM

Hi Carl

thats interesting.

I have found two kinds of clear discs. one being as thick as a normal CD, stays on the cd motor fine, but can start to flicker especially if batteries are down a bit (i use 2 x AA). the other disc i have found and used are very thin & flexible, need some blu tack or something similar to keep them on the motor but spin without flicker. I have also noticed that flicker appears to be more obvious in poor light situations (unless im imagining that!). In saying all this though, yesterday i shot a small piece of test footage using a normal thickness disc and there was no flicker at all.

Bob Hart April 1st, 2006 08:45 PM

AGUS35 APVE TO HDRFX1 - FURTHUR REAL WORLD TEST.

I got my greasy hands on the FX1 again for an afternoon. I took it and the Agus to a teenagers rock band competition at a local festival. I used it agile-portable as one could use the camera itself alone and found a few problems.

I found another camera-operator there doing an official recording of the event so extended the original intention of a few test shots into providing a bit of extra coverage, mainly close-ups and fingers working strings and frets etc..

The conditions were overcast and light under a canvas awning became a problem because of operator mismanagement. I did not use auto-exposure because of the overcast conditions which tend to aggravate burnout.

Despite some under-exposure which provoked some video noise, the camera hung onto the colours which remained rich. The video noise itself was of a finer texture than I have seen with the PD150, not unlike film grain. It is not necessarily a bad aesthetic but not one I would deliberately pursue. The correctly exposed shots held up well against some direct-to-camera footage I also shot.

The sound was not expected to be any good at all. The other camera operator had arranged for a sound recording off the mixer so it was not an issue. Surprisingly, the FX1 automatic audio performed remarkably well in conditions which occasionally drove the overload on my ears into the pain threshold.

Because the performers jump and move around a lot, following and framing with a fixed prime lens is a problem, especially if you are trying to stay out of another cameraman's field of view. A zoom would have been handy.

The loud amplified sound brought up an interesting defect with the combination of the glass disk, plastic housing and auto-focus. I use the autofocus for the relay as it seems to be just as effective as my own hand-eye skills.

However the autofocus which had been rock-steady, would drift when I was chasing focus with the manual lens and it took me quite a while to realise what was going on because it would spontaneously recover once I had hit the sharp spot with my manual focus. It initially just seemed it was taking me a long time to manually focus. It co-incided with times I was alongside the main speaker columns.

I suspect that loud sound is being conducted to the glass disk which may be vibrating just enough to set the autofocus off when the shot on the groundglass itself is soft right across the frame.

The gyro effect of the spinning glass disk showed its dark side during faster pans and tilts. There would commence a distinct vibration of about 5 Hz, which would transfer to the case/camcorder junction and shake the picture for a second or so after the pan or tilt was completed. My flexible disk-motor mount and the springs may be contributing to this.

The camera/Agus combination did not have any added bracing for sake of keeping the weight down. Added bracing to the camera baseplate would fix the problem.

I found the extra weight of the combination a problem for me after a while, especially when working with the camera held high overhead. Elbow joint and shoulder soreness set in fairly quickly and my shots with the 85mm lens handheld became unsteady and uncontrollable. This is probably more of an age and physical fitness issue.

I found myself tending to rest the back of the cam on my shoulder and using the LCD panel ENG camera style with close-up glasses. The panel was a little too close. An aftermarket eyepiece dioptre attachment for the FX1-ZI series might be a good move for some enterprising manufacturer, or an alternative eyepiece viewfinder working off the LCD circuit.

The other camera operator will be assembling a presentation using some of my footage where it is usable so it will be interesting to see how well the Agus images integrate.

Bob Hart April 2nd, 2006 08:54 AM

There is another clip up at savefle.com


The list of all files is at :-

http://savefile.com/projects/338360


The direct web address of the new file is at :-

http://www.savefile.com/files/6290311


The new file hopefully won't have the interlace defects the earlier clips have.

The conditions were - under canvas awning, intermittent overcast, time about 3-30pm. There is no soundtrack for two reasons, to reduce the data load and to avoid any copyright issues relating to the original musical composition.

Bob Hart April 6th, 2006 02:17 AM

If anyone has time to waste, I have put another two short H264 clips up at the following address :-

http://www.savefile.com/projects/338360

The names on the project file list are :-

AGUS35 TO HDRFX1 NO ENHANCEMENT 01

AGUS35 TO HRDFX1 NO ENHANCEMENT 02

"No enhancement is probably a little bit untrue. There's been an effort at de-interlacing them and they have been letterboxed but otherwise are not sweetened."

From a practical standpoint, I still think using the camera's own lens direct for wides and lots of movement and using the adaptor for the mid to close-ups may be a best approach.

The wides seem to lose a little sharpness at max aperture. They confer a interesting perspective effect in motion of objects moving directly towards and away from the camera.

Jamie Roberts April 6th, 2006 03:41 AM

Hi Bob,

checked out 02

footage looks great

no flicker there!!

Jamie

Roberto Lanczos April 8th, 2006 02:08 AM

I've spent like a week reading all of the posts. And when i started reading, i don't even knew what "GG" means.

Now, i don't have words for this. Is just great. Amazing.

But it's time to help a newbie. :D yes.

I've collected everything i need, and i've done some rough tests with all the parts on the fly, and it seems that i'm going to need a good macro lens, cause i'm still suffering from the vignetting.

So... Like i don't have a super cam, like the GL, XL, DVX, PD150, etc, i couldn't get the right information for the macro lens.

If anyone could guide me on this, that would be great.

Thanks in advance.

------------------

Here's what i have:


Camcorder ----- Sony DCR-TRV110 ( f=3.6 - 72mm, 1:1.4 @37 )

Lens ----------- Minolta SR-7 "50mm" ( Auto Rokkor-PF, 1:1.8, f=55mm )

GG ------------ Frosted CD from Maxell (25-pack)



If this macro lens can do the job for my cam, let me know to start building my adapter right now.

http://articulo.mercadolibre.com.ve/MLV-4973856-_JM

Wayne Kinney April 8th, 2006 02:21 AM

Quote:

Originally Posted by Roberto Lanczos
it seems that i'm going to need a good macro lens, cause i'm still suffering from the vignetting.

A macro lens, inside a 35mm adapter, is not intended to help with vignetting, although it does very slightly depending on its strength. The Macro lens is placed as close to the camcorder and possible and it's purpose is to help the camcorder focus on the GG while zoomed in. If your camcorder can zoom in and focus on the GG as it is, you dont need a macro lens.

What you do need is a condenser lens. Most commen type of lens to use is a PCX lens (plano convex) which is flat on 1 side and curved on the other. The flat side faces the GG and sits as close to the GG as possible. This is a good PCX lens to start with, and was used in the original letus and SG35:

http://www.surplusshed.com/pages/item/l3385.html

Good luck

Roberto Lanczos April 8th, 2006 02:34 AM

Quote:

Originally Posted by Wayne Kinney
Good luck

Good Luck? :(

-------------

I can't get close enough to the GG to avoid vignetting.

According to the info i've readed so far, i need a macro lens to get closer to the GG.

So... my question is: wich one will do the job for my cam?. Do i need 10x, 5x, 7x ?
Will this macro work ?
http://articulo.mercadolibre.com.ve/MLV-4973856-_JM

I wish i could buy any of the products you use, but i don't live in the US.

I will really appreciate any help. The only place where i can buy stuff, is Amazon.

Thanks

Wayne Kinney April 8th, 2006 02:46 AM

Hi,

No, the macro is indended to aid in the camcorders focusing. However, I think some have used the macro lens as a condenser lens (replacing the PCX lens) simply because this is what they have laying around already, and this is what you have read. But if your looking to buy a lens, I would recommend getting a PCX lens.

Please read this article:

http://en.wikipedia.org/wiki/Depth_of_field_adapter

There is a helpful diagram showing the most commen way of putting together a 35mm adapter, and illustrates what i meant with the plano convex lens against the GG.

Roberto Lanczos April 8th, 2006 02:56 AM

Quote:

Originally Posted by Wayne Kinney
No, the macro is indended to aid in the camcorders focusing.

You're totally right, sorry.

In fact, that's my problem. I get out of focus if i try to get closer to the GG. I tried everything, but it's imposible to get rid of the black corners.

I'll take a look to the article, thanks.

Wayne Kinney April 8th, 2006 03:13 AM

OK, i understand now.

Do you have a 35mm frame inside your adapter? Its a good idea to have a 36x24mm frame/window close to your GG, and this will be a reference for how far you need to zoom into your GG.

If you can zoom in enough to fill your LCD with this small 36x24mm frame, and focus, then you do not need a macro. If you still get vignetting while zoomed in to this point, you will need the PCX lens to avoid vignetting.

If you cant zoom in and focus on this 36x24mm frame, then yes you will need a macro of some sort. This macro will go as close to the camcorders lens as possible (probably a screw in macro). After this is installed, and you can now zoom in enough to fill the LCD with the 36x24mm frame, you will still propably find that you get vignetting and a PCX will be needed as well.

You can see in this diagram that both a macro and a PCX are used:

http://upload.wikimedia.org/wikipedi...nstruction.png

General rule is for the macro to go as close to the camcorder as possible, and the PCX as close to the GG as possible, with the flat side of the PCX facing the GG.

I hope this helps...

Roberto Lanczos April 8th, 2006 03:27 AM

I've tried every position, zooming, etc, etc, and no matter how hard i try, i always get the same portion of the screen on black.

something like this:
http://www.fdivisions.com/circle.jpg

I'll try to get the PCX. I just tought, i was close to build my adapter.


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