View Full Version : Homemade 35mm Adapter


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Chris Hurd
December 19th, 2003, 06:51 PM
Wow, 450 posts! This is the longest thread we've ever had. I've got an idea -- I was thinking about making a copy of this thread and boiling the copy down to the technical essentials, which would make it a little easier to read that way. You'd still have this one to reply to. I can update the copy with important info as it comes up. Let me know what you think,

Agus Casse
December 19th, 2003, 06:51 PM
I have been working in trying to flip up the image, but i still dont have any good results.. btw Paul, your designs wont work, i tried them and they are no good.

Joe Ryan
December 19th, 2003, 07:13 PM
chris, great idea, i've been an interested observer of this thread since day one, and there sure are a lot of the same questions getting asked over and over again.

jim, about 25mm/inch.

agus, i don't think paul was trying to pull a fast one, besides, copywrites (which only cost about $50, btw) aren't given to works in progress, and a patent would cost you about USD 15 000 (at least) if any of us had that laying around, we could just buy a p&s mini35. anyways, looking forward to your commercial version. way to go man.

happy holidays

Jim Lafferty
December 19th, 2003, 09:00 PM
Has anyone made one of these sucessfully for the gl1? If so which macro filter are you using and what are the distances between the macro filter and the gg and the fresenel lense and the 35mm lense?

I can answer your questions with partial confidence, as I'm about 85% done my GL1 adapter.

The macro power should be +7 or greater -- this allows you to move your camera in close enough to the surface of the GG and still zoom in to avoid vignetting.

I've got probably a half inch between the surface of my Century Optics +7 macro ("achromatic diopter") and the GG. I'm working on having about two inches between the GG and the rear of my 50mm lens.

If you've got a macro, you'll likely not need a fresnel.

However, and this goes back to my comment about partial confidence:

I put together a mock-up of my final adapter design last night and I couldn't pull focus accurately. I'm making an educated guess that this is because of the distance between the 50mm lens and the GG, which I figure was too short. I'm now extending the distance with a rubber ring between the F-mount and the front of the adapter.

Also -- I haven't actually shot anything yet, only looked through the viewfinder while holding my adapter up to the camera. No telling if my guesses, educated or ingorant, will prove to make for a functional adapter.

I will be done tomorrow, and plan to have footage up by Sunday. Check for it at http://ideaspora.net then...

- jim

Robert Knecht Schmidt
December 19th, 2003, 09:08 PM
I don't know whether anyone has already posted this link (http://www.spycow.net/) to a diagram and explanation of the Agus35 CD + spindle concept.

And after we have all this crap put into a box strapped to the camera, we finally have a picture that's more blurry, darker, and harder to focus and zoom. But that's what we want, because it will fool people into thinking you're filming on film instead of video. Isn't photography wonderful?

Not exactly a rave endorsement; nice schematic though. And check out the Fresnel link while you're there.

Agus Casse
December 19th, 2003, 10:03 PM
here is a new video made with a beta version of the adapter
like you can see.. there is no vigneting.

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

Now we are working on fliping the image for perfect control and making all the pieces to look pretty and profesional, as well as making a pro rod system and baseplate. as well as a matte box.

Jon Yurek
December 19th, 2003, 10:11 PM
Not exactly a rave endorsement; nice schematic though. And check out the Fresnel link while you're there.

Of course it's not a rave endorsement. The footage still isn't perfect because the device is still in development. But even if it were done like the Mini35, it's still harder to focus, blurry (because the background is in focus), darker (this adapter doesn't create light, you know), and we're doing it to try to make it look more like film.

Of course, I meant that ending line rather tongue-in-cheek anyway (yes, you linked to my website. Thanks. :) ). When I have the time, I want to make one of these adapters myself. And thanks about the schematic. I haven't put the macro lens nor any flipping scheme into it yet. Actually. I'll do that now.

Edit: Wow. Agus, that footage looks amazing. I had some doubts after some of your earlier footage, but that last clip really does look wonderful.

Edit 2: Near the 3:30 mark on that footage and onward, I could start to make out the edge of the hotspot on the edges of the frame. I assume this was because the sun was setting so you didn't have the same light, but how bright was it at the time, and how much light should we expect to have to work with as you have your adapter right now?

Devin Doyle
December 19th, 2003, 10:26 PM
I promised I wouldn't contribute anymore to this already gigantor thread, but after reading about someone else (Jim Lafferty) building their own mini-50mm for a GL1, I had to post a question!

Ever since the beginning of this thread several weeks ago I was under the impression that the fresnel between the SLR lens and the GG was solely there to focus the image onto the GG - even in my own "beta" version of the mini-50mm the fresnel performed this action. Jim , I noticed you said "If you've got a macro, you'll likely not need a fresnel." I must be missing something here, or maybe your adapter is built a little differently than mine - but I can't see why you wouldn't benefit from having both a fresnel lens to focus your image onto the GG and having a macro to allow you film something up close. Can you shed some light on this? Also...

You said you use a century optics +7 achromatic diopter. If I had the cash to squander, you'd be certain that'd be my "macro" lens of choice. However, I'm a cheap college student on a tight budget. I remember reading that the century achromatic diopters allow for zoom thru to a certain extent. Regular macros don't pull that off as well, correct? So in essence if you fail to get a powerful enough macro lens to get you close enough to the GG to fill the frame and avoid "vignetting," you wouldn't be able to zoom in and pull sharp focus would you? I guess in this case it's better to overkill and get a +10 macro lens - better to be closer than further?

Anyways, Jim I'm very interested in seeing how your set up looks/works as a fellow GL1 owner. Unfortunately my cam is in the shop for a faulty LCD and so I haven't gotten a chance to test things out, so I'm living vicariously through this thread!

Fenn Jacob
December 19th, 2003, 11:00 PM
I have followed this thread from the beginning, and was thrilled to rush into buliding mine. I collected all the materials, except lens, and was worried to find that I could not locate a clear CD. All of the ones I had were already frosted. I went through about 5 or 6 of them until I finally found a clear one, I was quite relieved. I should have just tried the frosted to see if it would work, now I'm glad to see that they are preferred. (I hope I didn't throw those frosted ones away...) As far as where to get them from I'm not sure. I know that most of them came from 100 pack spindles, gotten for free after rebate (boy was that a hassle) on the day after Thanksgiving. I don't know if its a feature of the higher count spindles or what. The Discs are old ones, so I'm not certain, but I think there is a decent chance they came from KHypermedia or Memorex. I'm not sure on this, but if your desperately against grinding the CD yourself, it could give you a start.

I am loving this thread! This is the funnest little project to work on, and impress your friends with. My following of this post here has been kind of sparratic, I just got to previewing Aguss's newest beta posting. BEAUTIFUL! I'm about 90% done on mine, 90% as far as consturuction goes. I think I'll have a lot of tweaking to do, so maybe only 30% as far as complete finalization. I've got to run to the local pawn shop and see if I can't find me a 35 mm now...

J. Clayton Stansberry
December 19th, 2003, 11:07 PM
Chris,

Please, please, please extract pertinent information and post to an Agus35 information thread. I think that would help us all! It would definite help me, because I can't find anything when I need it...

...on that note...I have completed stage one and wanted to offer what I have done and ask a question.

For connecting the box to the camera, I bought a UV filter, drilled a hole that size and super-glued it in. That way, you just screw the box onto the camera (just make sure you have it so when screwed all the way on it is straight! I didn't...learn from my mistake!) Also, you can then screw the macro right into the front of the filter due to their similar thread size! I have been using super-glue with good results...I got hot glue and super glue and decided to use super glue. It has worked great so far. The lens cap that goes on the back was used for the front to connect the lens. Thank you to whomever posted about that idea!

I have recorded footage without the fresnel lens (by the way, thanks Ryan for confirming that the fresnel lens is the same as a reading magnifier...I bought one in hopes that it was) or the spinning glass and it just seems to be darker. I haven't tried it in the day yet or on close ups. I also didn't notice a huge difference in the DOF as compared to footage without the Agus35 on. I hope (and know someone has stated it before, am too busy to read through 450 posts - another reason Chris!) that someone can tell me that the GG and fresnel will give me the DOF Agus is getting??? Please tell me this is what is missing for the DOF! If so, that's what tomorrow will be...a quest for DOF. Sorry for the long post. Thanks in advance from my fellow Agus35er's.

Clay

Charles King
December 20th, 2003, 03:11 AM
Hey Agus, great shots. Love the look. Can't wait for the commercial one. I'll be your first customer.

BTW, what is the humming sound in the background? Is it coming from the spinning of the CD?

Nathanael Jackson
December 20th, 2003, 03:30 AM
Hey, I've been following this thread and im scheming out my own little project...

We're mostly all using 35mm SLR lenses right? There should then be no need to put a fresnel in between that lens and the GG, as long as the GG is the same distance away as the film plane for that lens (there was a post on this maybe two or three pages back). If anything, I would think the fresnel would be just like the macro lens (but cheaper)...

Im not sure if I missed something, but what is the order of elements in your device, Agus? Seems like you've got the vignetting problem mostly solved. Does any vingetting become visible when the 35mm lens is stopped down, or filming in low light?

Another thing... Im worried that the box and the relatively heavy lens will pull down slightly, warping the image. Or the whole thing move as I'm filming...
Is there any place I can go to find out how to make a rail mount system, or where I can find specs/dementions of the real ones?

Stewart McDonald
December 20th, 2003, 06:32 AM
Agus, that new footage looks superb. What lenses are you using to get rid of the vignetting?

Helen Bach
December 20th, 2003, 08:53 AM
Here is a link that gives FFDs for various lens mounts.
http://www.gregssandbox.com/gtech/filmfacts/flange.htm
There are also tables in the likes of the American Cinematographer's Manual and David Samuelson's Hands On manual - but these are biased towards movie camera mounts.

The FFD is the distance between the mating surface of the body/lens (not the bayonet lugs, screw thread or whatever) and the image plane.

One inch is 25.40 mm.

If your lens isn't there do a search: just use 'flange focal minolta' or whatever because of the various names used for this.

If you want an upscale alternative to using a rear lens cap as your mount, look around for second-hand bellows adaptors. These are the mounts made for using lenses on bellows for close-up work. Try http://www.srbfilm.co.uk/ They also make custom parts very cheaply compared to movie industry places. They export.

Standard 'lightweight' Arri support rods (also used by everyone else for DV cameras) are 15 mm diameter, 60 mm centre to centre. These dimensions have to be very accurate for some standard equipment to fit. The rod axis is 85 mm vertically below the lens axis and the rods are equidistant from the lens axis (at least they are on my Petroff matte box). Some adjustment is usually possible for the exact lens axis / rod axis alignment. Plenty of people offer rod adapters as standard items. They aren't terribly expensive even when custom made.

Best,
Helen

Bob Hart
December 20th, 2003, 09:47 AM
To Chris: The condensing of the thread. Good idea. Soon enough we will be beginning to see thread deja-vu otherwise.

To All: A useless and unproductive curiosity question?

Has anyone added controlled lighting onto the groundglass to achieve an effect similar to that of pre-fogging motion film. It might be interesting in situations where the contrast exceeds the workable range of the DV camera. It might be interesting creatively if different colours were used, even more so if a known colour temperature offset was used and the lighting then adjusted back in post., ie., an effect perhaps similar to using an 81EF filter at sundown with tungsten balanced film.

Jim Lafferty
December 20th, 2003, 10:19 AM
I must be missing something here, or maybe your adapter is built a little differently than mine - but I can't see why you wouldn't benefit from having both a fresnel lens to focus your image onto the GG and having a macro to allow you film something up close. Can you shed some light on this?

Devin,

Well, maybe you're right -- I thought I'd read something in one of the earlier posts where Agus discarded his fresnel after installing the macro. Now I see, going over the old threads that this wasn't necessarily the case. My mistake, sorry. And so I have to ask -- is everyone using a fresnel and are they helpful?

Agus -- is the fresnel in your latest version of the adapter?

So in essence if you fail to get a powerful enough macro lens to get you close enough to the GG to fill the frame and avoid "vignetting," you wouldn't be able to zoom in and pull sharp focus would you? I guess in this case it's better to overkill and get a +10 macro lens - better to be closer than further?

I think this is all correct. I'd go with a more powerful macro either way you slice it.

I'll definitely keep you posted,

- jim

Filip Kovcin
December 20th, 2003, 11:40 AM
hello there,

as far as i can see - there is no info about manufacturer of frosted fake cds.
i have suggestion that anyone who knows the manufacturer who is definitelly NOT producing frosted/sanded CDs - to put it on the list, so we will be closer to that real one.

second thougt - does anyone knows how to make CD frosted with some chemicals? maybe this is much simpler than making it "mechanically"

filip

Jim Lafferty
December 20th, 2003, 12:00 PM
Just picked up a cheap fresnel and it doesn't help me -- at least, not yet.

I'm convinced my focusing problems are a flange focal length issue, but I've yet to find the proper distance between my lens and the focal plane (the GG). It's better, but still not acceptable.

When/if all else fails -- is a longer distance between the lens and the focal plane the best solution?

Incidently, I've got a Nikon Nikkor 50mm f/1.4 lens, part # 3958069. If anyone has the info that Google doesn't seem to turn up for me, I'd love to know...


edit: Helen -- the link you posted was down when I first clicked on it -- the link now works and I see that the distance for a Nikon SLR lens is 1.83 inches. Thank you for the info!!

- jim

Louis Feng
December 20th, 2003, 12:31 PM
The focal plane for the 50mm lens are 50mm away from the lens. That's the distance from the middle of the mirror to the focal point. On the lens it usually says something like f=50mm. If it doesn't say that, I would assume that because it's very common. If you measure the thickness of the camera, it gives a good approximation of where your GG should be.

Jim Lafferty
December 20th, 2003, 12:59 PM
Thanks. It's just that I don't have a Nikon at hand...

Got it working, however :D

- jim

Devin Doyle
December 20th, 2003, 02:27 PM
Muchos gracias for your response Jim. Good luck, I'm looking forward to seeing some pics + footage. Chris, I definately think this thread needs to be compressed - way too hard to find info in here!

Dillon Thomas
December 20th, 2003, 02:55 PM
Greetings

Someone over at dvxuser.com posted that he was able to uprez his DVX footage using S-Spline Pro (Software) - and to tell you the truth - the footage looks just about as sharp as the footage captured at HD rez. Unbelievable.

How about it? Agus35 + DVX100 + S-Spline Pro = 24p HD w/ DOF!

I'm in heaven. Now if only I could afford it!

Dillon

Look here for his experiment and clips (comparisons)
http://www.dvxuser.com/cgi-bin/DVX/YaBB.cgi?board=news;action=display;num=1071560094


quote:
what about the jvc hd10
can you tell me if theres any problem if someone makes a
agus35 on the JVC HDV CAMCORDER?
i THINK THIS WOULD BE A WONDERFUL THING!!
think about it
the resolution of HDV and the DOF
great
someone please try it.
ciao
end quote:

J. Clayton Stansberry
December 20th, 2003, 05:18 PM
Anyone find out where the pre-frosted CD's come from? So far from the thread this is what I have:

CD Packs that do not offer Frosted CD's:
Imitation
Fugifilm
Philips
100 pack $20 at Best Buy

Possibly have it:
Khypermedia
Memorex

Please let us know and add to the list so we can find out which pack it is...and then run out and buy their stock because you know they will be selling a hell of a lot of them!

Agus,
That beta footage is awesome! Do you have any recent pics of your new design so we can start drooling for the commercial version? Thanks.

Filip Kovcin
December 20th, 2003, 07:38 PM
i just checked Memorex 10s and 25s (at least in Poland) - they are clear ones.
but, tomorrow in the morning (polish time) i have a meeting with the guy who is selling huge ammount of CDs. he got ONE frosted cd - but no name on it - he found it in the shop somewhere, but at least i will know what CD manufacturers to ignore...

Bob Hart
December 20th, 2003, 09:45 PM
Chemical means of achieving frosted surface on disk!!

Those chemicals might be a little dangerous.
There may be some solutions but it would be irresponsible to post them here.

It could render me and the host of this service possibly liable for suit should tiny vexations like chronic dermatitis, blindness, chronic obstructive airway disorder and death emerge as collatoral consequences.

This is one area I would commend anyone not qualified to avoid like the plague. If you don't know it or can't do it, don't try. Chemicals are very socially enlightened. They don't discriminate. They just drop everybody. Seek help from somebody who has accreditation in this very specialised industry.

So you are going to go for it anyway. Whatever chemical you choose to experiment with, be extremely careful, avoid the vapors and don't leave the stuff lying around for little bro or sis to encounter. And for heaven's sake read the Hazmat notes, know what to do beforehand if it all goes wrong. Devise your personal or household counter-disaster plan if you have not already.

I don't think you will achieve by chemical means, anything you can't do with a lot less risk or hassle with graded silicon carbide grit or wet and dry silicon carbide grit papers or jobbing the task out to somebody who can gritblast with graded grits. That final 5% to perfection everybody looks for might only be achieved by experienced practitioners of specialised crafts.

The frosted CD disks people have been mentioning here?? Are they "frosted" right through the thickness of the disk or only on one surface??

If the "frosted" feature goes right through the full thickness of the disk, you will likely get inferior resolution, a halation effect into neighbouring image from pinpoint highlights and lower light transmission.

If the disk is only lightly translucent, your camcorder is going to also see through it into the front lens and you will get a hotspot in the centre of your recovered image.

There were two versions of the small "Pringles Chips" container press-on caps. One cap which originated from Belgium was a clear plastic with a frosted finish applied to one surface. These containers made excellent pinhole cameras for kids. The US cap was made of a translucent plastic which did not work as an image plane.

J. Clayton Stansberry
December 20th, 2003, 10:02 PM
Another solution might be to do what they do to make ground glass. It may also work on the clear CD's...just another thought...

Check out this website:
http://www.phototechmag.com/previous-articles/2003/mj-dokas/dokas.html

I am sure there are others, but may be another option.

Bob,

Agus has stated, after using the frosted CDs, that his resolution increased and there weren't any problems. In fact, by his latest footage, I would say he pretty much got it right! Don't know about where it is frosted as I can't seem to find one of these bloody things:( Will let you know if I can ever find one.

Paul Doss
December 20th, 2003, 10:59 PM
Agus Casse <btw Paul, your designs wont work, i tried them and they are no good.>

You are absolutely right! The one or two mirror versions do flip the image vertically but not horizontally. Back to the drawing board. Looks like the only way is to copy the SLR in as far as the light path through the viewfinder.

Paul

Don Berube
December 20th, 2003, 11:06 PM
For what it is worth - In the past, I have had clear pieces of glass turned into frosted pieces very nicely via sandblasting. I didn't do the sandblasting though, it was done by an ordinary local glass & window service company. The pieces were very consistent with each other and it only took the shop an hour to perform the job.

- don

Randy Reyes
December 21st, 2003, 03:33 AM
I have one frosted CD that came in a spindle but I forgot which brand it came i in. It could be Maxell or Primaris. They are definitely not from Fujifilm... :]

http://www.imagestation.com/picture/sraid93/pd6981a3f96a25751b76a28be5b610bee/fa3e9a51.jpg

http://www.imagestation.com/picture/sraid93/pce3cb261f697697c7010e87d21a72c9b/fa3e9a4e.jpg

http://www.imagestation.com/picture/sraid93/pfdfd18bebce77ffb524f1792d72ba330/fa3e9a54.jpg

Daniel Moloko
December 21st, 2003, 06:57 AM
hello there!!!

i have a trv18, just like Agus.

ive made some footage with the agus35, i did one exactly like the pic he put on the web.

and yeah, everything went out okey, just like the first exemple (the video of his father) he upload to the forum.

except the my footage has more vignette (? the spolight of the image and the black around it ?)

maybe its the distance from the 35mm lens and the ground glass. i will check it out (i just did it yesterday my first try)

anyway. but i found something really nice.

when i was pulling the 35mm lens from the PHOTOGRAFIC CAM (nikon), i just looked inside the cam.

i think its possible to make a 35minidv adaptor with the same GLASSES and LENS that we have on those usual photo cams.

i will try to make a black rubber box, with the lens adaptors connectors (the camcorder and 35m),and inside this box well
have all the glasses and lens we have on the photo cams.

the question is, maybe i have to re-size the glasses, re-made based on the photocam model?

or maybe isnt necessery, i just have to go downtown, to a used photo cams store, vampirize some cameras, get the glasses
and the lens from it, adapt it to the box and have fun?

what do you people think about it?

would we get the same 35mm image project inside the black box? is it possible?


ciao

Filip Kovcin
December 21st, 2003, 06:58 AM
i got mine frosted cd from guy who is selling lot of cds.

he can't answer me exactly what brand it is, definitelly NOT TDK!
a while ago - when i had a closer look i noticed that surface is VERY similar to frosted foil used to cover windows etc. in offices, homes... (you know - already prepared, with transparent glue on it, stickers type)
i just compared it now with a foil and it looks really close. i do not know about the picture quality, but will check that tonight when i'm finising "my" agus 35.

all the best,

"keep agusing!!!"

filip

Peter Sciretta
December 21st, 2003, 10:56 AM
This may be a stupid question...

But how are people connecting wires? ie the motor to batteries? I've tried duct and electrical tape and it doesn't seem to hold that good?

Jon Kamps
December 21st, 2003, 11:00 AM
I think solder would be the matrial of choice

Jim Lafferty
December 21st, 2003, 12:10 PM
Well, I got 'er functional today -- she's not pretty yet, and without a rail system in place the image shakes a bit much (going in and out of focus with it.) But, what can I say, I'm proud:

http://ideaspora.net/agus35/agustest.mov

(12.8mb Quicktime 6)

- jim

Don Berube
December 21st, 2003, 12:58 PM
I am sure that someone has already pointed this out earlier, but here goes. The frosted plastic that you are using in place of real optical ground glass is deteriorating the image too much. It is also causing you to lose too much light. Earlier, someone had posted something to the effect that "if you use ground glass, the image will be too bright". Well, if that is the case with this design, then the design is flawed and should be reworked so that you can use real optical ground glass. So far, none of the sample clips I have seen show an image that does not look degraded by the plastic. No offense, just an observation.

- don

Jim Lafferty
December 21st, 2003, 01:10 PM
Yeah, but expense and weight have to be factored into the design, as well.

I've got about five "ground glass" CD's here -- they cost me nothing more than I'd long ago spent on CDR's. If I drop them, or decide I want to mess with them to get different optical effects, I don't have to sweat their replacement and the costs incurred.

The question isn't (for me at least) 'How can I get the best image possible, at the expense of other considerations?', it's more 'How can I create an image that's acceptably interesting with the things I have at hand?'

- jim

Don Berube
December 21st, 2003, 01:23 PM
I would still say that as long as you limit yourself to using plastic in the image chain, you will be self-defeating yourself. Why waste all that energy trying to produce an "acceptable" image with plastic when you have the potential for an excellent quality image with glass? It's a simple thing that we have known for years - plastic does not produce good results in photography.

You mention "expense" - what is your budget cap? C'mon save yourself a lot of frustration and wasted effort, spend a little more and put some real glass in there. I dare say that it is not impossible to find an affordable glass solution by modifying the design a bit. Regarding finding an affordable piece of glass - has anyone thought of using a 2mm thick 4x4 or 3x3 mist or fog filter from LEE Filters or Cokin? Or perhaps an even-more-affordable resin filter from LEE or Cokin? Even a resin filter would be much better than plastic - but you really should use glass.

Again, no offense implied here, I'm somewhat impressed with what you are doing, really. It's just that the image is too deteriorated.

- don

Stewart McDonald
December 21st, 2003, 01:43 PM
I'd say the new footage that Agus posted is very acceptable for what I want, but I'm more interested in a movie look than high detail. Even if it has some grain (which I can't spot anyway), it adds to the effect.

Agus Casse
December 21st, 2003, 03:01 PM
New version with higher res...

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

Don Berube is right we are loosing a lot of light and considering that still havent installed a dove prism to correct the image. Still, cost vs performace is amazing... DOF is great, my TRV18 is kicking ass with no modifications or aditional investment.

hey Jim, thanks for that credit dude !!

i see that you are having some vibration problems, are you using a cd motor ? did you sanded the cd or was a already frosted one ?

Peter Sciretta
December 21st, 2003, 03:13 PM
I think don is also right but I think centering the disc could be a problem with glass... The cd disc is easy with a cd motor

BTW -

DON - I worked as a PA on your short film 2 years ago... did you ever finish it? It was a surprise to see you on this thread...

Agus Casse
December 21st, 2003, 03:16 PM
i think they can cut the glass center just like the cd, i saw some stores that have some glass windows with little holes. i will try up with glass next week if i am lucky, i really need to improve this for the comercial version, also i am still working in flipping the image.

Peter Sciretta
December 21st, 2003, 03:20 PM
agus - I think people would be satisfied in a commercial version if you could find either:

A. an output from the cameras RCA's that will flip the image normal for an external monitor/lcd

B. If you include an LCD that will flip everything.

I like the idea of the prism but I think it will cause too many problems plus it will just be one more thing the light must go through and will bring the light levels down yet again.

I don't think most people have a problem with flipping in post... the problem is to see everything as it is (right side up) while filming.

Agus Casse
December 21st, 2003, 03:22 PM
mmm

who else thinks about this ? that would be easier and cheaper, just to buy a LCD monitor that flips it than the prism.

Don Berube
December 21st, 2003, 03:27 PM
Agus, are those your sons or your nephews? They seem like good kids. You should name your device after them to reward them for tolerating your chasing them around with your device, which I am sure looks a little scary to them. hehe

Just curious if you could find a way to control the exposure more - so that you are not so overexposed in the white areas of the frame? It would be cool to see a nice flat, balanced exposure.

Is that sound I hear being made by your device? Is there a way you could deaden that sound? Reminds me of an old class at MIT, where the engineering students were given a Braun coffee bean grinder and the goal was to see who could figure out the best way to make the grinder perform as silently as possible. One solution was to deaden the walls of the coffee bean grinder with neoprene and to use a motor which was slightly over-rated for the task of grinding coffee beans. They lowered the voltage to that motor, so that it ran at only the torque needed to grind the beans and it was indeed a bit quieter. I would say that plastic shell of your device is resonating and somewhat amplifying the sound of the motor. Perhaps gluing a thin piece of neoprene inside the walls of your device (or around the motor?) would help mask the sound.

- don

Agus Casse
December 21st, 2003, 03:40 PM
yeah those are my newphies they are twins. :)

The problem really is that the mic of the TRV is less than 3 inches from the motor, so it is silent but the mic is too close. it can be solve using an external mic with no trouble. about the exposure, my bad i was so excited using the device that i didnt set it manually. but well :) i am so haappy that the optics are working well, and the image is not deformed like my first versions, and also there is no vigneting.

Don what do you think about a commercial version ? is flipping the image critical ?

Don Berube
December 21st, 2003, 03:48 PM
>>>>>>>Don what do you think about a commercial version ? is flipping the image critical ?

Absolutely! Anything less is a compromise. You want as few compromises as possible. You have to define who your target market is... hopefully you set your sights higher than just the people who only want to spend $60.

- don

Peter Sciretta
December 21st, 2003, 03:51 PM
I think, and I could be the minority but I wouldn't think I am... if it is a loss of quality or light steps flipping the image is not needed if you could somehow see the image right side up while you are shooting (ie flipped on a monitor or lcd).

I would rather that then lose quality.

Stewart McDonald
December 21st, 2003, 03:52 PM
Are you using a fresnel lens or macro between your GG and the camera Agus?

Agus Casse
December 21st, 2003, 04:01 PM
Yeah, a magnifying glass actually it is very powerfull i took it off froma wide conversion lens (VCL-0630 S)

Agus Casse
December 21st, 2003, 04:03 PM
Peter i still havent test using Glass, i am sure i will loose lest light with it than with a plastic cd, also the pentaprism or dove prism should be high quality to work...