try to make a metal skeleton from the camera to the adapter


BTW those rings looks beatiful, but how is that you will lock your lens ? you need a release button like the SLR camera have. i am about to post some footage, but i am low in webspace...

I'm about 1/2 way done my Agus35 Pro :)

I picked up a black "project box" from Radio Shack yesterday ($6.99), and a few other miscelanea...a switch, some wire, 9v batteries, a 9v battery clasp, etc. I spent about $18 total.

Then I went to Home Depot and picked up some epoxy ($5), a length of scrap 1/2inch PVC piping (for support rails - $0), a velcro strap ($5), and to attach the camera to the Agus35, a 3"-3" adjustable pipe coupling ($5).

I've got the other parts here already - an old Sony disc man, a clear CD from a spindle, and an array of cutting/drilling tools.

Incidently - if you plan on making more than one of these things, there are 54 and 57mm diameter dremel bits at Home Depot, that fit into a standard drill. Might be perfect for lens mounts.

The Radio Shack project box (dimensions: 8x6x3 inches; fitted back) is the perfect thickness for lens mounting - you just cut a hole the size of your lens, cutting notches where the lens pops in, and give it a twist - presto!

Preliminary pics:

http://ideaspora.net/box-front.jpg

http://ideaspora.net/inside-rear.jpg

Agus - email me if you need server space for footage. I've got a dedicated server with room to host plenty.

- jim

Yeah, the lens mount worked out OK, I guess. Little rough around the edges, but...it does lock into place.

Bob, over at Indieclub.com, advised using a F-to-C mount adapter to mount the lenses. You wound then just have to mill a hole in your adapter box and then you could switch lenses freely.

He also suggested using a chroziel matte box to connect the camera to the unit.

Here's an F-C mount (http://www.bhphotovideo.com/bnh6/controller/home?O=&A=ShowProduct&Q=&sku=77558) from Century Optics, costing $60.

Here's the link to the thread I've started, including Bob's advice (http://www.indieclub.com/tacoboard/thread.asp?ident=95126036193915&page=1).

- jim

I some people have been concerned with flipping the image in post. Maybe you could build an adapter that would "hold" the camera upside down??? Would this work??? Agus, have you tried this? I realize that you would not have accessibility to all controls, but as I understand it you get the camcorder dialed in and leave it alone....just thinking out loud....

That is the most ridiculous, absurd, WONDERFUL idea I think I've ever heard -- just mount the camera upside-down! That might actually work! And it'd give you a hair better picture quality because you'd eliminate the need for mirrors and prisms!

You'd have to use an external monitor, because your LCD and viewfinder would now be upside down, but that is a cool idea! You'd also have to rig up a mounting system so you still had a tripod socket, etc...

Not sure I'd want to show up in front of a client with it, but for guerilla indie filmmaking, that kind of thinking is the bomb!

Here is a tip for those that have too much trouble shooting inverted... flip a little the lcd screen just after it turns to mirror mode, in that way you will be able to get a corrected image.

hey agus, things are really moving along here, way to go.

just thinking out loud here, but maybe a couple simple design changes ( inspired by looking at an actual mini35, size and shape ) could help solve a couple of problems.

it seems to me that the gg in the mini35 is most likely the size of a silver dollar ( say 4 to 6 cm in diameter ) and most likely set at a 45 degree angle. if this is the case then you would be taking a picture of the image created on the side of the gg that it hits, instead of through the gg, seems this would make a big difference, in sharpness and luminance. the gg's so small you could go with glass instead of plastic, this also would be an improvement. this would also explain the vortex thing with the mini35, which i think we could get rid of by vibrating the gg instead of spinning (hmmm, where'd i get that idea, think orbital sander ). you would need one more mirror ( top of box/ unit ) and a relay lens ( maybe this would take care of the flipped image, not sure ) i think this could still be done on the cheap, and the unit could end up being smaller, well at least narrower.

i could be way off, but for the sake of experiment, i think i might have to give this a go, nothing to lose.

how's this sound, am i way off?

here's another Agus35 shoot test...

http://altoque.tv/35mmAdapter/Agus35maseratitest.wmv

you cannot put the GG 45, cause one side will be in a larger distance from the lens, what you can do is put a mirror 45 degres just like a SLR camera, and then you put the GG and then a pentaprims that correct the image...

(there must be a good reason why this wouldn't work)
What about just spinning the GG away and to the camera?

**POV of camera lens looking out**
[Motor]
|----------|
|---GG---|
|----------|
|----------|
[Motor]

**TOP View**
___
CAM|
CAM|
CAM|
CAM|
.|_|

__M__ //GG - from this view, GG spins clockwise (edges would be at 9 and 3 right now)

if you could spin the glass fast enough...would it create the same effect? maybe not...think of anything waving fast enough - it blurs and you cannot tell whether it is there or not at that instant...as long as you keep the shutter speed down? (which you would have to anyways because of light issues and trying to avoid seeing the grain on the glass. i am sure it is totally wrong...

another idea I had was to spin the glass from a wheel attached to the edge of the circle...think a polarizer...you can adjust it by turning it..but it stays in place the entire time right?
this might create the vortex effect people talk about with mini35...if someone could actually explain WHAT that is that would be great

if these ideas fail I am going to look into creating a sturdy agus35 of my own in the near future

congrats Agus!
Rob

seens too complicated and dont know if it would work, remember that the ideas is to keep it simple and make it simple to build, another thing is the vibration....

vibration is your worst enemy, cause it will be transfered to the camera and you will get bad footage. now... i thought of another way to make the whole box really small, but that will be in the commercial version... :)

Well I talked to my brother, who is a CNC machinist...and here is what he said:

"The camera rig doesn't look to hard to make after a little research on how it works. From what I can tell it is a rig that holds a video-camera in back of a special optical lens to record destorted images.It also looks full adjustable - I am guessing for different positions for what you would be capturing.

I think the best thing to do is get as much info as possible to see what and how the camera has to be mounted to the lense and what the adjustments do to the picture being captured.We can talk about it more over the phone or at christmas time. "

So I think if I can explain to him in non-video terms what I'm looking for, we can build a SOLID one out of metal and use REAL GG, and some rails.... for ALOT less than the real thing....

Cool!

Agus,
Everything with my adapter seems to be working out fine, except
that the image projected onto the cd is very dark. Is this normal and what can be done about it?
Thanks Mike Perkin

<<<-- Originally posted by Mike Perkin : Agus,
Everything with my adapter seems to be working out fine, except
that the image projected onto the cd is very dark. Is this normal and what can be done about it?
Thanks Mike Perkin -->>>

Be sure that the lens aperture is fully open, you will lose some light, like 5 steps, so indoor at night you will need to light up a lot... also check the max aperture size of the lens, mine is 1:2 and i get no vigneting and i have plenty of light... another thing is that the plastic GG will lose a lot of light as well.

Hi everyone, this is my first post here and this thread was the reason I joined!

I just started working on an Agus35 this evening but I'm concerned about wobble in the CD. I did my best to get it running smoothly when spun by the motor, but couldn't get it "flat" - the image tends to move. At slow speed it's very noticable and when spun up it makes things rather blurry. Has anyone else experienced this? Or even better, found a solution?

Also, there seems to be some pretty good gyroscopic force at play. My disc is spinning quite fast (the disc came loose from the motor once and took off across the room, bumping into the wall and staying upright and spinning for several more seconds). Has gyroscopic force been a problem for anyone?

And last but definately not least - has anyone attempted to properly backfocus their lense? I find it VERY handy when the focus marks on the lense match what's being focused on the film (or ground glass, in this case). It's a pretty precise thing (don't remeber the distance off hand) but I was wondering if anyone hand any tips on that.

So far it seems like a good project. I played around a bit with a 16mm lense and it was exciting! I have to go shopping for some 35mm lenses tomorrow :-)

<<<-- Originally posted by Ryan Henry : Hi everyone, this is my first post here and this thread was the reason I joined!

I just started working on an Agus35 this evening but I'm concerned about wobble in the CD. I did my best to get it running smoothly when spun by the motor, but couldn't get it "flat" - the image tends to move. At slow speed it's very noticable and when spun up it makes things rather blurry. Has anyone else experienced this? Or even better, found a solution?

Also, there seems to be some pretty good gyroscopic force at play. My disc is spinning quite fast (the disc came loose from the motor once and took off across the room, bumping into the wall and staying upright and spinning for several more seconds). Has gyroscopic force been a problem for anyone?

-->>>

Well about the cd coming loose and taking a spin through the room happened a lot to me :)... actually i broke 2 GG in the begining stages...

Ok, the problem is that you don have a good platform for the cd, so it comes and go... that is the hardest part, but seen like other people have been able to correct this with zero vibration using a cd player piece.

Congrats dude, and now that you have join there are also so many hot topics i this webpage that you will enjoy.

Given that ideas of manufacturing for profit or reward are starting to appear, it might be time for everyone to consider things legal such as intellectual property, patents, the possible infringement thereof and another perennial U.S. favorite, product liability.

The makers of the Mini35 and any existing competing products are probably not going to become injured if people home-brew by reverse design, their own versions for private use.

The makers of the Mini35 might even like the idea because videographers having tasted the fruits of a home-brew setup, might then hit a wall in terms of that last level of reliability/performance/perfection.

They might then buy the real thing when they need to perform consistently, meet deadlines and/or
manage to raise the price of the real thing.

However if a commercial entity evolves and eats into market share, you can be sure there will be
interest. If the point is reached where the costs of losing a patent infringement action become less than the lost revenue stream, then that interest can be expected to become active and interventional.

Stand-out key issues already are the number “35” in the applied context to describe the devices and the design concept. Though the Mini35 builder employs commonplace engineering and optical principles, the unique application and innovative combination of these, may constitute distinct intellectual property, sufficiently convincing for a court to decide to confer protection and relief.

If the Mini35 people are smart, they might pre-empt the marketplace with a strip version of their own product or a short-form kit of essential optical elements for home-brewers.

<==If the Mini35 people are smart, they might pre-empt the marketplace with a strip version of their own product or a short-form kit of essential optical elements for home-brewers. ==>

THat s the whole idea, to brake up the market and make it more accesible, just like the Ford T



Yeah,

we are all awared, and what is best, we will make it, and we will make also a comercial version, just like the chinese copy all and sell it cheap for everybody, we will make a homemade version of it.

I believe that the world is a like a big jungle, eat or be eaten, so in this case, we dont want to spend 12k - 16k in a mini 35 completed system, we want to spend 30$ bucks min... and many people are willing to spend 800 bucks in a comercial version, that let me mentioned, i never saw a mini35, neither knew or exactly know how it works... only the concept... that it is a camera obscura, and they have a spining GG, yeah... you can reach to that point and say "we need to shake or move this" as soon as you build the adapter and you see the grain...

So in conclusion, i will leave the germans to their bussines, which they are earning millions, me.... i will make it for free for all those who doesnt have money, and are poor indie filmakers like me... and for all others that want to spend an affordable price for a well build adapter... but dont have the money for a mini35, cause come on... lets be realistic, it cost a fortune !!!

Also, anyone no happy with this project should go and spend those 12-15k, cause either you like it or not.. the project is out, there are people building it, and more and more each day... just like the day that someone relase the first mp3, (well, thinking big...but) this is the same thing. Now with a camera less than 500bucks you will get DOF of 35mm cameras... which will be useful for those that in some future will want to film with real 35mm but cant afford the studies for it.. this is the perfect training... of course for free and with amazing video quality.

Thanks for everybody who support this project, and hey...this thread have been viewed more than 10,000 TIMES !!!...

I know where you are coming from and have no issue in bringing the product fairly to the masses who could never be in the marketplace for the Mini35 for the very reasons you state.

The open-source movement as exampled by the Linux community illustrates where it can go to the benefit of everyone and I guess this is the ideal you seek with the Agus35.

Like you, I like to experiment and innovate, some things work, some don't, - home made steadicam, window mount, camera crane which automatically tilts the camera at groundlevel and can be set to automatically find a preset height, all without added power, Super16 conversions of CP16 and Bolex H16RX5 motion film cameras.

One of the more morally bankrupt and unjust examples of patent exclusivity in recent times has been the attempt by pharmaceutical companies to effectively deny essential medications to people in the poorer countries by trying to block low-cost production of reverse engineered generic substitutes.

In relation to the Mini35 substitute, there are however some people who may be less protected in some countries from ruinous litigation than in others. They simply need to be mindful of this possibility and then proceed accordingly.

The open-source ideal, if this is what you are collectively embracing might best be protected by the Agus35 movement assuming some organised identity, registering and patenting its own innovations in all countries where there are builders before other players register them and lock you all out. Then make these innovations open to all to use on condition that furthur innovations built on the earlier work are themselves free to all designers. At the least, through company law in many countries, this might protect individuals from suit. The Linux open-source community model might be a good one to study.

How to mount it all to the camera:

Tape is a good ally, as well as hot glue, if dont try to build a lens mount, copy the shape and lock system from the SLR camera. then make a metal skeleton (you can use metal rods, or just a metal piece) that connects the adapter to the tripod hole of your dv camera.

Richard Mellor's most recent photos:

http://www.dvinfo.net/media/rmcameratop.jpg
http://www.dvinfo.net/media/rmcamsupport1.jpg
http://www.dvinfo.net/media/rmcamsupport2.jpg
http://www.dvinfo.net/media/rmfrontview.jpg
http://www.dvinfo.net/media/rmfullview.jpg
http://www.dvinfo.net/media/rmpicture041.jpg
http://www.dvinfo.net/media/rmsideview.jpg

Richard, where did you find this support? Do you have a part number, or any infos to help us to find a similar one?

the model number is:3420 telephoto lens support and it is made by manfrotto

This is too funny - it's almost as if this was made for the Agus35 :-)

http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=126662&is=REG

paulb

<<<-- Originally posted by Chris Hurd : Richard Mellor's most recent photos: -->>>

That's great. I'm assembling the rod system for my Agus35 Pro now, and I'm using a velcro strap from Home Depot ($4), too.

I found a used Nikon f/1.4 lens today for $120, and picked it up. Now I'm scouring eBay for an old Nikon body for sale - a lot of them that are damaged will go for $20 or so, which significantly undercuts the cost of the F-to-C mount adapter. I picked up a jeweler's screwdriver for $6 from Home Depot today and it should allow me to disassemble the bayonet mount with ease.

More to come soon...

- jim

Ok, maybe I'm missing something but why are people looking for F to C adapters? Is this so you can have a standard lens mount on the outside of your Agus35 but still use F mount lenses if you need to? Because the Agus35 fits between cam and lens other than that reason I don't see any other need for a lens adapter.


Aaron

It's so that if people want to be able to interchange the lenses easily, they can. Without it you'll be gluing your lense straight to the mount. This way it gives people the option of not limiting the lense to only this adapter and also gives people the ability to choose different lenses.

<<<-- Originally posted by Chris Black : Seems like it would have to be at least 7 or 8 inches away before you could start to focus? .....Can you explain how you are achieving the focus at such a close proximity?

thanks,

chris -->>>

Chris -- you need a macro adapter, which allows your camera to get focus at objects less than an inch or two away from your lens.

Agus is using a wide-angle/macro adapter built for the small, 1-chip Sony cams - it goes for about $35 off of eBay, I think. The unit is two pieces - a small macro attachment that sits behind a wide-angle attachment - they screw apart, giving you access to the macros function. Depending on the size of your cam, the adapter is threaded for 37mm, and you may need a step-up ring.

If you have a GL1/GL2 or another camera with 58mm threading, Century Optics makes macro adapters going for $210.

- jim

Hey, i drew a diagram of how I THINK it is built like. agus, plz let us know if it is correct. and i also have 1 question, how are you keep the entire thing connected to the camera lense? doesn't it fall off?

http://www.metafilms.net/upload_images/agus35.gif

or link: http://www.metafilms.net/upload_images/agus35.gif

The GL2 does in fact have a superb built-in macro mode. Take off the lens hood, zoom out all the way to full wide. As long as there's enough light, the auto focus will pull in objects tack-sharp right to the surface of the glass. I've shown this feature to people many times, and it works great!

Instead of ground glass or sandblasting or the like... what about using some FROSTED MILAR film. I've used it for shooting rear projected slides and as a diffuser for shooting HD from 4X5 transparencies. for the thin film I sandwiched it between glass or just taped it to one side of a glass sheet. You might be able to go with a plastic that's thicker and avoid the glass altogether.... Just a thought

<<<-- Originally posted by Chris Hurd : The GL2 does in fact have a superb built-in macro mode. Take off the lens hood, zoom out all the way to full wide. As long as there's enough light, the auto focus will pull in objects tack-sharp right to the surface of the glass. I've shown this feature to people many times, and it works great! -->>>

This won't work with the Agus35, though, as you need to zoom in on the suspended picture (not out), and you're not going to have a lot of light at your disposal. Which leads me to...

<<<-- Also, I've been searching ebay for a 35mm lens to buy, and got lost in the hundreds of options...what are some good lenses for the Agus35 setup? -->>>

You want to get the fastest lens around, which for a reasonable price would be a f/1.4. There are new, faster lenses - a new f/1.2 runs for about $560 new, half that used, but f/1.4's go for about $120.

Incidently, Canon makes an f/1 that goes for $2,600!

Re: the frosted mylar - where can we get some?

- jim

Would an f/1.8 lens do?

About the focussing using Gl2, how about if you brought the projected image closer to the lens so you don't have to zoom in on it? You can then manually focus whilst in macro mode to focus the image?

<<<-- Originally posted by Chris Black : <<<-- The GL2 does in fact have a superb built-in macro mode. -->>>


Sure enough. I tested the gl2's macro capability ...and it's amazing ......i took a piece of paper with writing on it ... ....took off the lens hood ........and literally held the piece of paper about 1/8th of an inch from the lens ...and it focused perfectly ....crisp and clear. ....

thanks chris ..



chris -->>>

You both seem to be missing the point, though: you cannot simultaneously engage the Gl1/Gl2's "macro mode" WHILE filling the frame with the suspended 35mm image.

You have to zoom IN, not out, in order to get the projected image large enough so that it encompasses the entire frame of your DV camera, while simultaneously remaining in focus manually. This way, you do not get vignetting or a black, circular border in your DV frame.

Auto focus will not work, as the camera is constantly receiving different information about what to focus on - the spinning disc, the image on the disc, the footage coming through the hole, etc.

I'd love to be proven wrong, and then I wouldn't have to spend $210 on a macro zoom (or $100 on an appropriate magnifying glass.)

- jim

Indeed, GL2's macro works only at full-wide angle.

I did a few more basic tests with the gl2 macro function. ......Like it has been pointed out, in order for the macro to work properly, you must be zoomed all the way out. But at that point .....you can literally hold your subject up against the end of the lens housing ..and it stays in focus .........so ....couldnt you just mount the camera close enough to the spinning cd ...that you wouldnt have to zoom? .... ............

the next thing i tried was .......moving the subject about 2 to 3 inches from the camera lens .........I then was able to zoom in about half of the gl2's optical range (Not sure if the camera was still in macro mode or not)....and still have the subject clearly in focus. .....I'm not sure if this would be enough zoom to eliminate the vignetting.....


I plan on building an Agus35 for my gl2 ....but it will probably be 2 or 3 weeks before I can get to it. I will definitely include details photos and descriptions of the process.

Chris

Chris, I own a GL2 (actualy the XM2 PAL version). It is imposible to zoom and focus on a 35/24mm rectangle without a close up lens. For this purpose I've used a philatelic lens.
I have another philatelic lens between the 35mm lens and the GG. Very close (aclmoest in touch) with the GG. This removes the vigneting on the GG.
http://www.utdallas.edu/library/special/wprl.gif

So the question remains. Can you get the GG close enough to the lens of the gl2 (without zooming) to eliminate the vignetting?

Chris

you need a magnifying glass from the GG to the DV camera.

Ok, Cosmin said he used a magnifier between 35mm and GG, and Agus said between GG and camera. Which is correct? I would think that Agus' is correct cause if you magnify the 35mm image won't you lose some of the DOF?

Couple more things. Have people had more success with the GG near the lens, or near the DV camera. People seem to be doing different things here too. I would have thought you'd have to have the GG the same distance as a 35mm image place to get the correct DOF, otherwise you'll be getting more or less than real 35mm.

And, couldn't you just build a long adapter so that the GL2 can focus on the plane or is that still not possible?

Aaron

<<<-- Originally posted by Aaron Koolen : ...couldn't you just build a long adapter so that the GL2 can focus on the plane or is that still not possible?

Aaron -->>>

Possibly - but why would you want to? I can't imagine a benefit of a larger, more unwieldy setup.

On further note of the magnifying glass situation - larger magnifying glasses (i.e. those that match or exceed the 58mm diameter of the GL1/GL2's lens) are insignificant in their magnification power. To get a 3 or 4x magnifier, you need to either: go down in diameter (unacceptable as you will get considerable vignetting); or spend upwards of $100, with no guarantee that the lens will work appropriately (and a lot of work and a bit of risk to figure it out in the end.)

The macro zooms from Century Optics are your best bet, though they do up the cost of your adapter considerably. Be sure to get the +7 adapter, though, as this puts lens placement within 3 inches of the subject possible. +2 puts your lens 10" out. You can then use the macro function separate of your Agus35, too.

- jim

Couple more things. Have people had more success with the GG near the lens, or near the DV camera. People seem to be doing different things here too. I would have thought you'd have to have the GG the same distance as a 35mm image place to get the correct DOF, otherwise you'll be getting more or less than real 35mm.

People are putting the GG in different places because that's where they are focusing the image, that's all. It doesn't really matter where the GG goes in the adapter as long as you can get the SLR lens to focus on the GG and the DV camera to focus onto the GG. You may want to do it so that focusing would be more like properly focusing an SLR lens for the right distances, and that would take more work than the simple ad hoc solution that some people are likely taking here.

And, couldn't you just build a long adapter so that the GL2 can focus on the plane or is that still not possible?

Of course, but the longer you make it the more unwieldly it will become and the less likely you are to be able to use it handheld anymore. Also, it will be harder to keep it aligned properly unless you have supports.

Ok, i will clear this doubts for once and for all..


The magnifying glass goes between the GG and the DV camera, and the GG has to be as close as possible to the DV camera until there is no vigneting.

Dont get confuse, and the best way to solve it is to find a cheap wide conversion lens, and take the first lens that indeed maginfy and a lot... that will cost ya like 35 bucks... dont find and expensive one and also you dont need one that have the exactly the same diameter, cause you zoom half way in (my camera case), so you can find a cheap wide conversion lens for any cheap dv camera, and just use the part that you need.

Keep it simple, and you will get better results :)

OK i'm jumping in I have a done a "dry" test; frosted glass, nikon lens, XL1 and a cardboard box. No fresnel or mag glass. No moving parts I want to get a feel for everything before I move on. It really works I'll have some stills later.
My main question is, in the mini35 what all is handled in the relay lens section? How are they over coming the 7.2x magnification of 35mm lenses and 1/3" CCD's? what could we use in place of this my goal is to replace the 16X lens of my XL1 to reduce the amount of glass the image is coming thru.

great jorb Agus, when are you posting your plans?

Luke

Well, this design basically depends on the camera lens being
in place. The XL1 is a difficult camera if you want to remove the
lens because you will have to replace it by a "relay" lens.

The 7.2x magnification is gone because the image is projected
onto the ground glass (the CD) instead of on the CCD directly.

<<<-- Originally posted by Agus Casse : Ok, i will clear this doubts for once and for all..
Dont get confuse, and the best way to solve it is to find a cheap wide conversion lens, and take the first lens that indeed maginfy and a lot... that will cost ya like 35 bucks... dont find and expensive one and also you dont need one that have the exactly the same diameter, cause you zoom half way in (my camera case), so you can find a cheap wide conversion lens for any cheap dv camera, and just use the part that you need.
-->>>

Agus,

Just to be clear, when you say "wide conversion lens" you are talking about a Macro lens? And, you don't have to connect it directly to the camera? Could you explain this....because I think that would be a great way to connect it - put on the macro lens and there you go!?!

Thanks,
Clay

<<<-- Originally posted by J. Clayton Stansberry :
Just to be clear, when you say "wide conversion lens" you are talking about a Macro lens?
Thanks,
Clay -->>>

What Agus means is that inexpensive Wide Angle lenses have a separate Macro lens attatched. Simply buy a cheap combo, and discard the Wide Angle portion, and you have a Macro lens all by it self. SEE:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2970304852&category=29964

As you can see in the description and photo is states "With Macro". You can see the ring on the bottom of the lens that reads MACRO.

Hope this helps,
Spence

OK more discussion on the XL-1 conversion.
if the 7.2x magnification is no longer an issue then would it be possible to get say a xl1 to nikon adapter and a good macro lens for your relay? What other issues would need addressed from the GG back to the CCD. Is the relay also flipping the image or is this handled by mirrors inside the unit.

Thanks everyone keep up the good work.
Luke

To test your relay lens options, take your camcorder along to the place you intend to get your relay/close-up/macro lens from and ask to be able to test one.

Take with you also, a test card or probably better, a translucent panel, with a frame drawn on it, the same size and shape as the 35mm image frame. On this frame there should be drawn a grid of parallel black lines, horizontal and vertical, at least eight each of even spacing, thickness and opacity.

Look for in the pattern of lines :-

1. Distortion. ((II)) = barrel distortion ))II(( = pincushion distortion.

2. Variations in sharpness across image, most likely to be apparent in corners or sides.

3. Variations in color across image.

Retailers, if co-operative at all, may only allow you limited instore testing opportunities of the quick and hand-held variety with a salesperson impatiently hovering.

If you are going to be handholding something that does not fit your camera, up to your camera lens to test it, cut yourself a short straight length of wood for a jig, with several holes bored down a straight centreline marked on it. This is to mount your camcorder on at one end so that you can hold the added lens and image target in a steady relationship with the camera lens by bracing down onto the wood or even sit the object on it if it won't fall over. You'll some small scraps of ply or cardboard for packing so you can get it centred vertically.

Also improvised testing itself may introduce an unequal distortion or variation of focus across the image. This will be apparent on one side or upper or lower edge of your test image.
Deficiencies in your intended lens setup will most likely be equally represented in quarters of of your test image provided your added lens is centred on the centre axis of your cameras own lens system.

There is a caveat to all my babble here. With some camcorders, the centres of the tripod mount hole, and centre axis of the lens system do not co-incide. With some camcorders, the centre axis of the lens system does not fall in the centre of the CCD array. This may be due to design or variations in build quality. With my PD150 (PAL), the lens centre axis and tripod mount are off-centre by about 6mm. The tripod hole cannot be used as a centre reference. My PD150 lens centre axis is also offset slightly to the right as viewed in the recovered image (to the left in reality).

Some of the Iraq night-vision images framed wide for best subjective resolution (circular image inside the frame) have the same offset my own tests showed, so it may be a characteristic of the camera.

For the same reason I had to dress the left side of the optical path through a 16:9 adaptor to eliminate left edge cropping on fully wide.

This is probably a lot of useless info for most. Feel free to add to, criticise and correct where necessary.

I also thought about using something instead of or on the CD. I work in a theater and we have plenty of gels laying around as well as diffusion.

Gels are cheap to purchase and I thought either Rosco or Lee made a solid sheet version, but I can't find it right now. The diffusion comes in different strengths and patterns and is quite consistent.

If you contact a theater supply store you can request a (usually free) swatch book containing small samples of different gels, diffusions, etc.

<<<-- Originally posted by Luke Andrews : OK more discussion on the XL-1 conversion.
if the 7.2x magnification is no longer an issue then would it be possible to get say a xl1 to nikon adapter and a good macro lens for your relay? What other issues would need addressed from the GG back to the CCD. Is the relay also flipping the image or is this handled by mirrors inside the unit.

Thanks everyone keep up the good work.
Luke -->>

Yeah I suppose you could, but it would be cheaper just to get some form of close-up adapter I imagine.

Also if you have an XL1 you can just turn the viewfinder upside down by mounting it backwards, if you see what I mean.. It's not ideal, but it's cheaper than any other solution and there's no loss in image quality.

kieran