PCX stands for plano-convex lens which means it is flat on one side (plano) and has a positive curve on the other (convex). There are different letters that designate how the different lens types are made. P = plano, D = double, CX = convex, CV = concave.

Here is a link that describes how the PCX lens (also called condenser lens or field lens) improves the image by dispersing the light http://topcontechnotes.home.att.net/...tem/page4.html. The link is to page 4 of 16 that completely breaks down the SLR camera's imaging design, which is the exact same technology used in these adapters. I recommend reading all of the pages, they'll help you get a much better understanding of the designs.

One other advantage to using a PCX lens is that the flat surface can be ground and used as the ground glass.

Thanks for the help.


On the matter of reading through the post. This I have actually already done. When I stumbled across this forum by accident, I found the agus post and started reading there. Before I knew it, I had spent all night reading them and it was 7am. At the end of the agus posts, it mentions that there is a new topic started on the static adapter, which brought me here.I read through these, that very morning till about 10am. In retrospect, maybe it wasn't such a good idea to do this.Reading for so long, I may not have been able to take so much in, but it was addictive reading and was something that was incredibly interesting. From when I first started reading in this topic however, the posts have come thick and fast. There are now twice as much.Trying to catch up or find things you may have missed,has become more difficult.Especially when you are searching for parts or waiting for them to arrive.It's hard to get perspective.

thanks

Louis Demontez
 

Paolo Rudelli have start new place to discuss about the adaptor but in french. It's interesting because everything is separate by element or section. Section for each element of the adaptor.So it's easyer to find what your looking for.This could be a interesting way to go if the new thread ("Alternative Imaging Methods ) become available.

Alain Dumais

Ps: here is the link
http://forum.aceboard.net/i-36808.htm

2.5" PVC Source in Canada
 

Anyone know where to get PVC piping in 2.5" width in Canada? The only available sizes at Home Depot / Building box are 2" and 3", no .5". This is both in the electrical and plumbing departments. I asked an employee who told me 2.5" is a special size only contractors can order in bulk. Any ideas?

Test whit cylinder lense.
 

From Brett Idea

Here's is my first test whit a cylinder lens.
I have use a 2X lens that is made from acrylic ,very cheap for testing the theory, that I have grind the plano side ,still some scratch on it.
On the left side ,the image normal, right is the image scale to 16-9 ratio( aprox)

http://www.kheops-tech.com/~ad3d/16-9test.jpg

Alain Dumais

Heres my test clip, in Quicktime format.

Its a Panasonic DV953, static 35 w/ condensor and macro(S35CM), Olympus OM1 lens, no correction done in post. And NO ZOOM! thats the whole frame.

When I focus, the damn lens zooms in and out, its a piece of crap lens, I should get a nikkor someday that is more zoom stable.

Right click save as, 10mb
http://aequantum.com/alian35.mov

Heres my setup
http://aequantum.com/35test2.JPG

Finally done! (until I get a nikkor anyways)

16/9
 

Alailn

super your test of cylinder lens

how exactly you put the cylinder lens in your aldu35 ???

A+

PAolo

Aldu35 for xl1
 

this is my Aldu35 version for the xl1 mounted on the camera, notice the flipped eyepiece which rightsides the image.

http://www.dinoreyes.com/images/cam1.jpg

the adapter on top of this next pic is made with a achromat diopter and pieces below are the parts broken down and numbered to show the stacking order. the next version i'm making will use a holographic diffuser and a condensor lens.

http://www.dinoreyes.com/images/cam2.jpg

i'll post up some test video soon...
-d

XL1
 

some body never tink or try to remove the lens of XL1 end put strong condenser lens to "send" the image direct to the CCD ??

yes paolo, the relay lens is the tricky part of this unit. i had a lengthy discussion with some optical professionals concerning this matter. what i learned is that optics and optical tricks are a bit of a mystery in that you won't know what happens until you put the right sequence of lenses together and discover from there. in the end they wanted to charge me 5-10k (USD) to "attempt" at solving the problem. i thought it would be much cheaper solution to just buying a fast wide lens that i could reuse anyway...

btw, nice french site-i know how the french love cinema....
-d

here's a down and dirty video (qt) test with the xl1 version, with a fast 55mm master lens, something like this...

http://www.dinoreyes.com/images/test11B.html

Here another maybe interesting link for lense

http://www.oriel.com/netcat/VolumeII...ge/v3t1cyl.htm


http://www.oriel.com/netcat/VolumeII...e/v3t4disk.htm

Alain

Which Cylinder Lens?
 

OK, So I'm probably going to ask a dumb question but lets just say I slept through all of my optic design classes.

How do you determine the squeezing power (no idea what the correct term is) of the cylinder lens? All of the supplier sites I've visited only offer dimensions and Focal Length. What is a 2X lens? Is there a way to calculate the 2x from the diameter and the Focal Length? These lenses are expensive so i would like to buy the right one first time around. Can someone (ahhmm Brett?) give a quick leyman's tutorial on lens terminology? I think many of us newbies would find it very useful. Better yet, can someone just make a recommendation as to which lens to get for the different aspect ratios? Thanks. Joe

Oh yeah! one last question.
Alain, did you replace your condenser lens with the cylinder lens or did you add it to the cylinder lens? Did I understand correctly that the cylinder lens would replace the condenser (PCX)?
BTW, Alain, your first images with the cylinder lens look great! How much tweaking in post did you do (beyond fixing image orientation)? Thanks for the link to Thermo Oreil. Joe

John Gaspain,

Your rail design is great! It looks even more solid than the P&S. The way it adjusts for cameras and lenses is simple, functional, and has good lines. I haven't seen many designs, but yours has some good ideas. I'm thinking of using stainless rails and aluminum stock, but I need it to somehow be able to adjust balance on a heavy duty fluid head.

Joe Holt
 

Yes I have replace the condenser and the GG whit the cylindric lens that is grind on the plano side.
I have only rotate 180 deg and squash it by aprox .7 verticaly, that's why I say 16-9 aprox. The lens we are looking for should be a cylinder lens that has a horizontal power of 1.33X.

Alain

Alain, do you have any footage, taken with the cylinder lens that we could see?

Also, what are the specs of your cylinder lens and what would the specs of a cylinder lens that has the horizontal power of 1.33x be?

Basically, what effects the horizontal power, of a cylinder lens?

thanks

Louis Demontez
 

Actually I have use a Bar Magnifier to make the test. I cut it ,grind it and I have remove the GG and the condenser to put this instead .

Bar Magnifier Model # if F.
http://www.ultraoptix.com/Pages/suprvision.html

Now I have to find the good lens.
For the exact spec I don't know yet.

http://www.oriel.com/netcat/VolumeII...ge/v3t1cyl.htm

http://www.oriel.com/netcat/VolumeIII/pdfs/v31cyl.pdf

Before I put footage I will try to have better result.

Alain

anamophic
 

alain this looks great . I have been working with a anamorphic lens on my aldu35 it is a kowa 16-h 2x lens it has a adjusment from
5 feet to infinity I guess the image created is a2.66 I have to put it in power dvd ,and stretch it out .I emailed chris some stills of the setup ... I need a rail system..... some of the clips look realy cool .I plan on building a 2.66 screen to play this on with a dlp.
this adapter could also be used to turn a4:3 projector into a 16:9
panamorph makes a lens for projectors that does just that it,s around $700

Lapping Film for GG
 

Has anyone tried this instead of Grit for ground glass grinding? I was doing a search recently for 3 micron grit, and came across these 'Lapping Films' for polishing fiber optics. Apparently an even coat of 3-micron Aluminum Oxide 'fastened' to a piece of film. You would use it like sandpaper... supposedly used for hand-polishing. I was thinking about giving it a try... In general you can get around 100 sheets (3" x 6") for approx $25 USD... Just wondering if anyone else has tried this approach? Btw - they make lots of 'grits' of this stuff - 1 micron, 0.5 micron - 9 micron, etc...

I have a heck of a time getting a good grind at even 1000 grit (9 micron) without causing scratches. I have tons and tons of water, but it just never seems to work out - and I end up scratching. How 'hard' to people press down when grinding? (Doesn't seem to matter - I scratch no matter what I do).

Any advice?

Scratches are a real burden. For what its worth, here's my suggestions. I'm not a glass worker so this may be all wrong.

Chamfer or rub back the corners and edges so that chips don't spall off sharp corners and get into your mix. I find one of the new diamond had laps for sharpening kitchen knves handy for this. Clean up scrupulously afterward.

Don't wear out your grinding mix before renewal to the stage where the glass "sticks". That's where your scratches may happen when the surface pressure goes way up.

Using separate glass sheets for dressing your groundglass on for each grade of powder. With each dressing, clean off the sheet entirely between adding each renewal of powder. Don't use too much at a time.

Be absolutely careful not to allow the powders to become cross-contaminated. Only one grain and it's all over for that particular level of fine finish.

Patience. Lot's of rubbing in small circles and not too much pressure.

The work area must be absolutely clean.

Interesting Find
 

I found this while doing some research:

http://www.arri.com/infodown/cam/broch/viewfind.pdf

Wow! I didnt think my idea to use cylinder lenses would be so popular. Great! Thanks Alain for the credit. He's right about the mag. number btw. A cylinder lens with a 1.33X mag. will give you 16X9 if your dealing with a DV format frame ratio. Now if you want perfect cinescope (around 2.35. Not 2.66) you'll be hunting down a cylinder lens with a X1.78 mag. Since your unlikely to find a "X1.78" lens exactly just go with a X1.75. You wont be able to tell the difference. Hey Alain did I tell you it was going to work or what? Hows the hot spot correction working out for you with that 2X? Its a cleaner looking picture with the GG and cylinder lens combined. Thats because you wouldnt ever be able to get a seperate GG that close to the cylinder lens. I wonder though about your chroma abberations. After all the cylinder lenses used in the Panasonic 16X9 attachments are two element achromat cylinder lenses. Check your edges and post some high res pictures.

Im cooking up another idea now too that will add another dimension to the adapters but its pretty out there so let me screw around with it first before I post it and get people going in the wrong direction. Thanks Alain and everyone for all the great links posted recently. I didnt know about the Arri directors viewfinder. Should look into that.

Brett Erskine
Cine/Videographer
www.CinematographerReels.com

possible image inversion solution
 

I don't know if this has come up already. What if:

1. the roof pentaprism was placed directly behind the lens, re-orienting the image and projecting it 90 degrees upward

2. a 45 degree mirror is placed directly above the pentaprism, turning the light path horizontal

3. the groundglass was placed immediately after the mirror.

lens > prism > mirror > gg

two potential problems come to mind:

a. would the prism behave properly with the light beam coming out of the back of the lens, which is different from a focused image on a ground glass.

b. could the light path be short enough (e.g. about 45mm from rear of lens through all elements to the gg?

I don't have the parts to try, maybe someone else in the forum can give it shot.

2 cents worth, josh

Brett Erskine wrote:
<< you'll be hunting down a cylinder lens with a X1.78 mag. Since your unlikely to find a "X1.78" lens exactly just go with a X1.75.>>

Brett,
Thanks for the tip. How do I get a X1.78 mag. or X1.78 mag. cylinder lens? all of the suppliers I've been searching through only offer dimensions and Focal Length. Is there a supplier that describes their cylinder lenses in magnification power? I've checked with Thor, Edmonds and others that have been posted here. They all use dimension and focal length.



Thanks Richard Mellor for the link to the Arri Viewfinder. It goes to prove that a correctly oriented version is very obtainable. The roadblock I've run into is finding a roof pentaprism with a large enough clear aperature to accomodate the video camera's lens. 35mm SLR pentaprism is too small. Does anyone know of a source for a large roof pentaprism? I thought about using a roof pentaprism from a medium format camera but I don't have one laying around and they're quite expensive for a test. If anyone out there has one, could you test to see if the viewfinder is large enough to zoom your video lens to get a clear picture through the camera without seeing the edges of the viewfinder? Thanks! Joe

Michael, that Arri adapter looks interesting. With the little handle there, it resembles an old 8mm camera. I've been searching on the net and can't seem to find any information other than the brochure you posted. It looks a lot like the mini35 with handle. Either way, its certainly interesting.

Hi,

Is there any other caracteristics whe should hunt (a part for the 1.33 / 1.78 magnification power) for the cylinder lenses ?

And what about the condenser lens what are the "best caracteristics imaginable" we want ?

I ask so because we (french guys from Kandinsky's "Mini35 Faq" forum) may have the opportunity to have thoses type of lenses especially made for a very reasonnable price.

We may also have them precisely grinded by an optic company, but what should we ask for ? a 3 microns grinding ? less than 3 microns ?


Besides all that, i'm a DVX100 user, should i look for specific Cylinder / Condenser lens (72mm diameter for example) or not ?

Thank you optic pros for answers !

Nico

Oops
 

Michael,
I mistakingly thanked Richard Mellor for the Arri link. Sorry. Joe

Nico whos the manufacturer? I can give them specs. Send me a link/contact info. Thanks

We have two possibilities for now

http://www.legrand-optique.com/

http://www.optique-commerciale.com/presentation.htm


Both are small french manufactures and usally only deal with other companies / stores. we contacted them and they have accepted to have a look at the "problem".

I don't know if they speak english and / or deal worlwide for now.

Their contacts are on their websites, but i think it would be better if their contact was a french speaking and french based person (don't you think ?)

you can post all specs here or on our french forum

http://forum.aceboard.net/?login=36808

or e-mail them to me

Thanks Brett

Nico

hi, my result with my panasonic nvgs70 and mini35 kit.

a camcorder with a mini35 kit :)
http://www.ifrance.com/mini35/Image%20002.JPG
http://www.ifrance.com/mini35/Image%20004.JPG

a picture of my test.

http://www.ifrance.com/mini35/Comp%201%20(0-00-29-14).jpg
http://www.ifrance.com/mini35/Comp%201%20(0-00-52-00).jpg
http://www.ifrance.com/mini35/Comp%201%20(0-00-15-15).jpg

are you a sugestion ?

<<<-- Originally posted by Gregory Joltok : hi, my result with my panasonic nvgs70 and mini35 kit.

a camcorder with a mini35 kit :)
http://www.ifrance.com/mini35/Image%20002.JPG
http://www.ifrance.com/mini35/Image%20004.JPG

a picture of my test.

http://www.ifrance.com/mini35/Comp%201%20(0-00-29-14).jpg
http://www.ifrance.com/mini35/Comp%201%20(0-00-52-00).jpg
http://www.ifrance.com/mini35/Comp%201%20(0-00-15-15).jpg

are you a sugestion ? -->>>

im not a sugestion but I did save a bunch of money on my auto insurance.

Nice pics- a condensor might be in order

usable ?
 

Hey you dvx100 user, do you think that somthing like that:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3807276418&category=29964


Would be of any help in our goal to make an Aldu35 for the DVX ?

Nico

yeah.... sooooo.... how does that cylindrical lens fit into the lens? before the gg??? i'm assuming your using a round one verses a rectangle one...

also, fyi, my testing with a holographic diffuser yeilded nothing promising. i had a 10 degree LSD. i had hear through an optical specialist that that would be a better version of the gg, but as someone else also reported, it doesn't work.

A 10deg holo diffuser is no good, it's surface is simply too rough. I also tried the 20 deg, it's not that bad, but the hotspot is very pronounced. The 60deg was the best with respect to smooth picture without a hotspot, but it's way too dark. The 20deg may work if you have a suitable condensor.

For those trying to make a bosscreen, you may want to look at microcrystalline wax. It has higher melting point than paraffin. I couldn't find any local suppliers, and mail-order guys sell in 10lb qty; that's a LOT of bosscreens :). As for the procedure (someone mentioned bubbles): read up on candlemaking, it's suggested to use a water bath to melt the wax, and keep it 'simmering' for 30min to get rid of the bubbles.

Thanks for the post, Roman. How did the 20 degree diffuser look as far as grain?

Also, if you don't mind, if you could post your holo diffuser results as a new thread, it would help narrow down these huge Aldu and Agus threads.

Eliminating Ground Glass althogether
 

Hi all,

I'm making this adapter for the HDV camera (JVC JY-HD10) and with its 1280x720 resolution, the GG grain issue becomes catastrophic.

After some experimentation with grounding of the UV filter glass, which proved still unacceptable even with the very fine grit (started with 9, finished with 25), I'm waiting on the Bosscreen material... but I don't hold my breath for it either.

So, is there positively no way to eliminate GG altogether? What if we use not 35mm SLR, but 16mm movie primes, thus making the "projected" image smaller and closer to the native size of the prosumer cams' CCD?

Rotating the GG will get rid of the grain effect, hence the eliptical(?) motion used in the real mini35.

Alex, take my opinion for what its worth (I'm no expert), but I tried in vain to take this route. I was also bothered by the visible grain - as well as the light loss, and tried taking the GG out of my adapter and simply using a relay lens. I got a great image - no question - very bright and completely grain free... but exactly the same depth of field as my video camera is used to.

I have rationalized this result to myself with the following (likely delusional) argument:

Depth of Field is determined by the relationship between the size of the hole the light enters and the size of the imaging area. The ground glass literally creates a different sized intermediate imaging area. It makes the image-making a two-step process - First an image on the ground glass - second, a different image on the CCD. Without the ground glass - there is only one imaging step... the CCD. None of the optics in between seem to comprise an 'imaging area' in my novice experimenting.

This also negates the possibility of simply using different lenses (16mm, etc.) for the same reasons. 16mm film has a significantly larger depth of field than 35mm film for exactly the same reason the video cameras have large depth of field: the relationship of the image area (a piece of 16mm film or a tiny CCD) is much much smaller than a piece of 35mm film, so the 'circle of confusion' which creates a shorter depth of field is reduced.

I realize this post is likely just 'so much mumbling' but I tried this approach and failed. However, if you're like me - you probably won't believe it until you give it a go yourself. If you succeed, let us all know!

On another note - in reference to grit size, when you say 'started with 9, finished with 25' what do you mean? I would interpret the '9' as meaning a 9-micron grit size (around 1000 grit). 25 microns would be larger than 9 - causing much more visible grain. Just confirming. From what I've heard, (but never seen) the goal is to get down to about 3 microns at the final stage.

Grit sizes: I ordered 5,9,12 and 25 from gotgrit.com. I haven't done grinding myself, rather my worker did; if I understood him correctly, 25 was the finest while 5 was the roughest. In any case, this doesn't matter much as I hated the results at every stage of the process due to the very visible grain.

I expect to get Bosscreen Friday, will report the progress with that (supposedly grainless) screen.

Would be super if Bosscreen material worked... I'd hate to have any moving parts in the adapter (the only alternative to the static screen that eliminates the visible grain)...

upside down monitor solution
 

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

filip