DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Alternative Imaging Methods (https://www.dvinfo.net/forum/alternative-imaging-methods/)
-   -   Homemade 35mm Adapter (https://www.dvinfo.net/forum/alternative-imaging-methods/17195-homemade-35mm-adapter.html)

Spencer Houck December 10th, 2003 04:49 PM

<<<-- 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...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

Luke Andrews December 10th, 2003 09:21 PM

XL-1 ideas
 
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

Bob Hart December 10th, 2003 09:53 PM

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.

Ryan Henry December 10th, 2003 10:48 PM

Ground Glass Alternatives
 
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.

Kieran Clayton December 11th, 2003 12:09 AM

Re: XL-1 ideas
 
<<<-- 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

Peter Sciretta December 11th, 2003 06:50 AM

Update:

Went over to best buy where they are selling a very cheap cd player/discman for 17.99 with a 5 buck instant rebate... so 12.99 plus tax leaving the store. Took this thing apart with a srewdriver and found that the motor that spins the disc can be completely seperated from the rest of the board and stuff... giving you the red and black wires off of the motor in which to hook up to a battery pack (which you can get at radio shack... I have a 2 triple A pack.) In between I also have wired a on off switch (also from radio shack). And believe me if I can do this... anyone can because I don't know crap about electronics. This is also the best way to do this thus far. The radio shack toy motors Agus reccoments make WAY too much noise, not even usuable with a boom, and vibrate WAY too much (that could be fixed with a stable design but why not just spend the extra 10 bucks and get the cd player motor and you won't spend endless house trying to center the cd on the toy motor and kill yourself when you realize the shots look great but you'll never be able to reccord dialogue with a device using that motor). So believe me... use the cd motor!

I am using a wide angle adapter I had (minus the wide lens like agus is doing) for my trv20 on my sony pd150. Problem is that you must zoom in a little to get away from the vinnetting of the actual lens. I went to NEWTONVILLE CAMERA looking for a macro lens and first off the clerk on the phone told me this adapter was not possile and tons of people were coming into his store recently buying and returning lenses, no one ever successful. I went there and proved to him that it does indeed work, however he was unable to produce me a 58mm threaded macro lens that would work with this device. (he had some macro lenses but they went out of focus before you could zoom out the vinnetting.)

Robert Martens December 11th, 2003 07:26 AM

I also managed to remove the motor from an old, broken CD player I had--only broke a few weeks ago, too, good thing I didn't throw it out! Stripped the wires, tapped 'em to a AA battery, thing spun up just fine. Best thing is, since it's a portable player, it has the little springy-ball "clip" style spindle. Holds the CD in place without glue, and spins at a nice speed (I think).

Now I just gotta get the equipment necessary to mount this bad boy to my VX2000, and the means to attach a lens to the front, and I can finish this project.

Peter A. Smith December 11th, 2003 09:16 AM

Peter or Robert, what was the model of the cd player or is it just any old cheap discman? I might buy it today and finish my version of the Agus35 using 35mm film cans by tonight. I already got an image and i just want to better stabilize the system by using another can before i post pics. I'm using tiffen macro lens +1, +2, +4 combined for a +7 for $39 at a local photo store. It worked out fine, but it seems using the cd motor might be the solution to the vibration sound problem.

Bob Hart December 11th, 2003 09:51 AM

For Peter Sciretta. - I used a generic 42mm eyepiece of chinese origin to fit Tasco telescopes, extracted the lenses to make up an adaptor from PD150 to PNP-HG night-vision intensifier. This frames the 18mm diameter display tightly top to bottom when the zoom is wide and corner to corner at about 25% in. It wouldn't be any use for the 35mm image frame size but a lower power two element lens set of similar design might.

In my early prototyping I used a similar less powerful lens set in a sub-assembly out of a Sony VCR16B telecine adaptor (a 16mm C mount lens, a macro spacer, a mirror, a ND filter and the two lenses in a module, all enclosed). This framed closer to the 35mm frame size and needed a lot more zoom to come in to frame onto the 18mm diameter display tube target.

There might be some benefit in experimenting with 90degree consumer telescope eyepieces and barlow lenses. I think the eyepiece lenses may be too powerful, but there may be something there - just a thought.

Both of these lens sets I describe do not erect the inverted image.

Jim Lafferty December 11th, 2003 10:37 AM

Just to tie some loose threads:

Agus's sugestion of finding a "cheap wide angle" with macro is fine, but you have to be sure you're getting one large enough for your lens's threading. For the GL1/GL2's out there, a good choice might be this one. Not sure if the VX2000 has the same threading...

CD motors are great design choices -- they're so quiet.

Uhm, that's it for now.

- jim

J. Clayton Stansberry December 11th, 2003 10:38 AM

For those using a CD motor - AWESOME! I am glad it worked. Could you tell me how far you are putting the CD away from the lens, I mean are you having to extend it out very far (I know this will differ for different cameras, but I am speaking in general). And, if you are, how are you doing it? I will be making the trip to Best Buy soon...thanks for the info Peter!

Clay

Richard Mellor December 11th, 2003 11:38 AM

Peter -

In answer to your question about the telephoto lens adapter ... the slide on the bottom of the support has a screw to adjust the length of the arm. So you'd have another 6" extension that you don't see in my photo.

Sorry for the lagged response (been very busy during Christmas season). Can't wait to get back to work on this project.

Richard

Chris Black December 11th, 2003 01:20 PM

Ok. im a little confused. I'm trying a very basic test version of the agus35 ..... i have a box ...a vivitar lens. ....a piece of ground glass (clear cd rubbed with sand paper) ....then i have my gl2 lens in the other end of the box. ....i can see the image being projected onto the GG. ...and I can focus on it. .......But heres where I'm lost ......You can see the projected image just fine ...but if you look PAST the ground glass ....you can see the light source from the vivitar lens ...which is much brighter than the light that is hitting the GG. ........So when the gl2 is focused on the projected image ...you can see this dime sized ...bright circle of light ...coming from the lens ........how do you get rid of that? .....Do you have to zoom into the dime sized bright circle area? ...I cant imagine that ....because it is such a tiny area. .... ..................maybe im totally lost ......

any ideas??


thanks,

chris

Aaron Koolen December 11th, 2003 01:45 PM

Chris, I think you're right and you have to zoom. I've heard something like this mentioned in this thread before. That's why I think you really will need a macro lens etc, to be able to focus that close.

Aaron

J. Clayton Stansberry December 11th, 2003 01:46 PM

.....chris......do you have the.....apeture wide open?.....as i understand it......haven't made one yet....you lose a lot of light........make sure apeture is set at it's most open position.....lowest number......1.8.....or something like that......


All times are GMT -6. The time now is 05:35 AM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network