Hey all,
I know there have been plenty of folks posting frame grabs since the start of this thread that most of you all wouldn't be interested in checking these out. I would like those who have successfully created a static adapter to give me some feedback and perhaps give me a hint on how I can fix my barrel distortion problem. I'm using a 60mm dia. 60mm F.L PCX lens with the flat side ground with 5 micron WAO. I did about 10 minutes of CEO grinding. This removed all of the minor scratches from the WAO grinding. The convexed surface of the condenser faces the video camera lens. I was considering using a longer F.L. PCX but I am worried that the hotspotting will return. Any ideas? Thanks, Joe

http://www.paddlefilms.com/adapters/April 9 far focus mailbox.jpg

http://www.paddlefilms.com/adapters/April 9 near focus mailbox.jpg

http://www.paddlefilms.com/adapters/April 9 far focus.jpg

http://www.paddlefilms.com/adapters/April 9 near focus.jpg

Bravo...

i am realy impress whit yours resault
specialy whit the grain on near focus images...

What about your SLR objectif => ??mm/f??

again bravo

joe,

what kind of camera you are using?

filip

Wow Joe, those looked great - very very little grain in your GG.

Joe,
I just ordered a 50mm diameter, 50mm focal length lens from Edmund Optics, but after reading about your barrel distortion with a 60mm focal length, I'm hesitant to use my 50mm (it will be worse). How bad is the distortion? I see the left side of the mailbox bends a little bit, but still looks okay. Can you post a still frame of your adapter focused on a grid to show how much distortion there is?

I'm afraid I may end up trying to get two 100mm focal length lenses. That's supposed to decrease the barrel distortion but still diffuse the hotspot as much as a 50mm (two 100mm FL lenses in series equal one 50mm).

Joe: Great job! I am also curious as to what video camera you're using.



I think this will be my last framegrab post for a while, as I think I've got my ground glass about as refined as I can get it. Looks like the next step is to figure out how to use microcrystalline.
Actually, I need to get a regular uv filter to grind, as I am currently using a linear polarizer, which is dark like a ND filter. This is probably not helping the grain situation much.

The only post I did on these was curves (warmed the images a bit) and letterboxing. (Honestly, I pulled back on the zoom a bit to try and get less grain, and in doing so I revealed the edge of the adapter. This may be a good tradeoff. I'd have to use the 16:9 guides when shooting, though.)

Another thing: I'm shooting this with a GL2 w/ the sharpness turned quite a bit.

www.frankladner.com/images/t3_01.jpg
www.frankladner.com/images/t3_02.jpg
www.frankladner.com/images/t3_03.jpg
www.frankladner.com/images/t3_04.jpg
www.frankladner.com/images/t3_05.jpg
www.frankladner.com/images/t3_06.jpg


Thanks!

That look good , but still some grain in the last image.
What are your slr lens, 1.4, 2.0 ? I have a 1.4 and 2 and there is a big difference in grain, whit 1.4 I have no grain but whit 2, I start to see the grain.

For the distortion, in my experience I have notice that the distance betwen the macro lens and the camera lens as a influence. I know that the closer the better, in my case.



Alain

All,
Thanks so much for the positive feedback. It means a lot coming from you all. I used a Minolta MD mount 50mm F1.4 lens. The lens was wide open for those shots. I used a sony PD100A (that's the little Sony DVCAM before the DX10)
I had the camcorder on full auto (except focus)
I didn't do any fix in post except to orient. What you saw was what was on tape.

My set up doesn't use a dipoter lens. I just point the video camera lens at the condenser. My condenser is a 60mm dia. 60mm F.L. PCX from surplusshack.com Here's a crude diagram:

[SLR] [)ground pcx [Sony]

I zoom the Sony in until the lens won't focus on the GG and then I back off a hair. If I zoom out too far, I get severe vignetting.

I was wondering if I should try to find either a slightly longer focal length lens such as 60mm dia. 65mm FL or get two 60mm 120F.L. lenses and grind just one of them.

(]{) {= GG

Unfortunately, I'm comitted to 60mm dia. due to design reasons. I would have to do a major rebuild to change that.

Nicholi,
Have you tried surplusshack for your lens first? Their prices are great. Usually $4 for a PCX. Much better for experimenting than Edmonds' prices. I'm curious to see your results. I say you should have better results than mine with the barell distortion because you will use more of the 50mm dia. lens with your image than I did with my 60mm dia. If you look at a PCX lens, the convex is more severe at the center and tapers as you near the edges. I believe this is why I got the distortion. The 36mm x 26mm image I'm shooting only utilizes roughly 65% of the PCX. Oh well, give it a try and let us know how it works out.

Frank,
Your images look great too. There is definately some vignetting going on. I've noticed that it is more noticable with bright subjects but with a bright subject, you can zoom in a little on the GG because the grain will be "burned out" more. Are you using a fast lens? F1.4 seems to be a requirement for low grain with these static adapters. You can also try opening the iris on your video camera (without turning on gain) and slightly over expose the GG. Than you can drop the luma in post. Try that and turn your sharpness back up in your camera and you may get a completely different look to your images. Just a suggestion.

Thanks again everyone for your kind words. Any ideas about the barell distortion would be appreciated.

Joe

Joe: Thanks! I'll have to try what you recommended. That sounds like it would work, so long as I don't blowout to complete white w/ no detail. Excellent tip!

,Frank

Obviously an optical solution would be better, but here's an idea for those who don't mind doing a bit of post processing to get acceptable results.

Shoot an evenly illuminated white background. Now you can use this frame in your NLE to adjust the luminance of all the frames in your movie.

Everyone's NLE or Compositing software will handle this differently so direct your specific questions to the appropriate software forum. Or course a lot of people here can field general questions.

Is this perfect, no. Will you have the full latitude (grayscale range)as before, no. But it may work for a lot of you.

The same thing could be done printing an inverted image to positive slide transparency and placing it on the 35mm lens side of the GG. The transparency could work as a gradient neutral density filter with the most dense part of the filter in the center.

there is also another possibility - you can use filter called hotspot, with VIrtualDub program. both are free.

filip

here is some footage of a new updated version of my lens, i finished off the inside with flat black paint, more fine tuning. the codec i used on this version cut about +30% of the color saturation of original uncompressed-so the uncompressed footage is very juicy in terms of color and depth.

i had originally planned on shooting a dv version of short in-camera edited film we were working on at a closed bar in midtown new york, but due to many time constraints i wasn't able to. the footage you see here [sorry it's upside down still] are some actors waiting at a bar before their scene and some others going through a walk through of parts in the background...

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

i think VERY promissing overall...
-d

http://www.glassmart.com/etching_cream.asp

http://store.artcity.com/arp-150xxx.html

Here is a safe alternative to HF and H2SO4 based etching solutions.

It's about $7 to $10

Do a vivisimo or google search on glass etching cream to find more.

http://www.rhoadescameras.bizland.com/Camera%20Creation/Ground%20Glass/ground_glass.htm

is an example of a piece of glass treated with some cream.

http://www.greatlakeslaboratories.com/cne1.htm#Coverage

has a MSDS sheet for the material. It is phosphoric acid based so all you need is proper ventilation, goggles, gloves, and water nearby to rinse off should you get spattered.


From what I've been reading you must clean the glass very well and leave the etching cream on a long time at the proper temperature to get an even etching effect.

I would wash using ammonia in a sonic bath (jewelry cleaning bath) if you have access to one. Otherwise just let it soak overnight. Then remove the glass holding only by the edges with latex gloved hand. Rinse with tap water then add the cream.

I'm going to be trying this out soon. I'll let everyone know how it works.

James the Chemist

Hey All, hope the addiction is treating you well-

I thought I'd pass along a discovery. I was frustrated with the amount of grain in my ground glass, so I was trying some other materials. One of the batch was a 10-pack of "Clear Project Files" from Office Depot. they are 8 1/2" x 11", Item #741-341. Office Depot brand.

These are translucent files for putting paper in. I used my ground glass (removed from the holder) as a template and found the cleanest, scratch-freeless spot on one of the folders and traced my ground glass. I carefully cut it out with scissors, giving me two circles of this translucent plastic the same size as my GG. I put both circles into my holder, put the retaining ring back in and tried it out.

Its significantly better than my ground glass, and I can't see any grain. It actually showed me that I have scratches on my condensor which I didn't know I had (next problem, I guess)...

At any rate, it was good enough for me to say I'm sticking with this instead of my GG. The ten-pack of folders was around $5

It's super cheap, super easy - might give it a try and see if you get similar results. Just passing it along. Enjoy :)

http://homepage.mac.com/dvx100/iMovieTheater1.html

Hey Jonathan, can you post some footage of your static adapter using the Clear Project Files translucent material?

I'll try and put something together later tonight -

<<<-- Originally posted by James Webb : http://homepage.mac.com/dvx100/iMovieTheater1.html -->>>

James,

That looks fantastic! I would love to see a larger res file of you test! I am considering getting the DVX100 and want to build a static adapter for a short I'm working on.

Could you give us more information on your adapter? Perhaps post some pics of the camera with adapter or a brief explanation of your approach. Or email me with some info? I was very impressed with your results.

Thanks,
-Dana

I put up some clips of the File-Folders-As-Ground-Glass as requested by Ernest.

At the very top of my adapter page is a link to my own server. Not sure how well this will work, and these are also first attempts at encoding clips for the web, so there's lots of potential problems here :) Let me know if any of it doesn't work for y'all.

http://home.austin.rr.com/aqua99/adapter/

Follow the link at the top to ALTERNATE GROUND GLASS MATERIALS: and (hopefully) you'll get a page with some links to the movies at the bottom.

I'm hampered by both my out-of-date gear and my experience level :) but there ought to be enough here for you to decide whether to drop $5 on some file folders or not. Enjoy-

By the way, these tests showed that the file-folder may work for some projects, but bloom the heck out of highlights. Not the right 'look' for everything. I might try some drafting mylar sheets next.

Your "bloom" maybe the result of using 2 layers of the folder material. You may want to try only one layer, perhaps supported by the glass from the uv filter ring.

Thanks Dana,

I'll put some info together soon.

I consider the images to be very good (@f1.8) although the grain on the GG becomes pronounced @ about f4-5.6. I think the GG is about as clean as I can get it (WAO 5) but I can still see a few tiny specks (e.g., dirt, scratches). Not sure. I haven't had the time to check to see what they were. Maybe on the condensor.

I've found that the GG is the key. I'll definitely continue to search for the best material for the GG.

Thanks James,

I am really looking forward to your information! What lens are you using in that demo? Are you changing your aperture (on your SLR lens?) or are you leaving it wide open?

I can hardly wait to hear more details! Ooh, and pics :)

-Dana

Dana-

Yeah, I was changing the aperture on the 35mm lens from f1.8 to f4 or f5.6 (I don't remember exactly). The iris on DVX remained wide open @1/25.

My lens is an old (50mm) Konica.

I'll try and put some stuff together by the weekend.

-J

Just tried Myler sheets; its a no go, the grain is too large

http://homepage.mac.com/dvx100/PhotoAlbum2.html

Looks great! Could you post some full resolution shots with the camera?

Thanks!

Here's some images:
http://homepage.mac.com/dvx100/PhotoAlbum3.html

Looks great James!
Just a few questions...

Are you using the original DVX100 or the "A"?

I could see some grain in your blacks (that's where you're going to see it), but I didn't see any vignetting. Are you zoomed into a smaller than 36mm x 26mm image? I thought most DVX100 users were using +7 diopters instead of the x10 you're showing in your diagram photo. Have you tried using just adding a +2 to one of your 5x? It could be that I don't know what I'm talking about as I don't have a DVX100 but am interested because I plan on getting one to replace my Sony soon.

With my Sony, I zoom out until I start to see vignetting and then I tap the zoom lever just a pinch to get the largest image possible without vignetting. Can you do that with your DVX100 or do you have to keep the camera wide with the macro adapters?

Keep forging ahead. There are lots of us eager to see your results. The DVX100's Cinelook color technology coupled with the 35mm DOF should make a very impressive combination.

Joe

your aldu35 was made the same as mine I think this is the best design .I sent chris some photos of the rig . my filter rings are 52mm a 50 mm plcx fits inside. it is fitted with the internal threaded filter ring washer this also is used to hold the ground glass. and to get the just right focal length the washer can be used as a spacer . a local camera store had a bin of scratched
filters, and a cannon 50mm 1.4 lens.... thanks to everyone
it looks so simple now ,but it took a lot of work by a lot of people
to get to this point. I wish i new a place that I could tell people
to buy blank filter rings for 2 or 3 dollars .some factory has to make these things

Wow James! That looks REALLY clean! nice build! I was wondering if you were planning on building any sort of rails system to support the weight of the 50mm lens way out there? Is it pretty heavy that far from the DVX front mount?

You're really tempting me to go out and buy the DVX this weekend (I can't as I'm in the middle of getting a mortgage loan) hehe. But damn am I tempted to start my static 35 project after seeing your results and your approach!

The screen grabs you posted look great to me!

What was the total cost of your setup (minus the lens)?

Thanks!
-Dana

Joe-
I'm actually using (2) X10 macros. That was suggested by Brett Erskine. My camera is a 1st generation DVX100 with 190 hours on it. I haven't checked to see where I'm at in relation to 36mm x 26mm. I plan to this weekend. I can say this to those familiar with the DVX, I was zoomed in to Z60 @MF06 (if that helps). I can zoom out to Z47 before I start seeing the barrel creeping in the corners. But at that point it appears that "shadowing" is still present on the sides. So to be sure I got a very clean image without any vignetting I zoomed to Z60.

Richard-
The filter rings method is very solid (and strong). I had to buy them for $5-$7 each. I got a few for free. I ended up using too different thicknesses of rings. A certain combination of both were necessary to get just the right length. A trial and error method ;) I decided to glue the lens on. I glued on the (silver) lens mount from the camera body to the lens as well. It made for a secure fit if I glued the lens to that before glueing it in the step-up ring. Of course it also had to be figured into the measurement of the focal length.


Dana-
The lens is very heavy (and strong). As you can see in the QT, I was holding it and pulling focus - it was pretty unmanageable. Something will eventually have to be done to accomodate it. I haven't counted up the receipts yet. I bought some things that I ended up not using too. Like (2) very nice 55mm Raynox Tube Extensions. They were slightly too long for the focal length of my lens.

I mentioned earlier that the lens was a 50mm - it's a 52mm. Not a lens of choice, just one I had.

Thanks guys!

James I see you have been paying attention in class. Thanks for the credit. Its always nice to get something back after putting in soooo much work on this thread and in my design. Besides the idea of using two Hoya +10 Macros (Watch out. My heads about to get big) I also proposed the idea of using condensers instead of fresnels, ACHROMATIC close up diaopters instead of single element diopters and thoughs 72mm to 55mm step down rings but dont worry I promise I won't sue ;-)

I do have to give you major credit on finding just the right combo of filter rings to achieve the proper distance between the 35mm lens and the GG. I didnt think this was going to be possible because if your off by even a millimeter all of your focus marks on your 35mm lens wont be accurate, or even worse, you lose your minimum focus or the ability to focus at infinity. I went with the idea of a adjustable extention tube to not only make sure it was right but allow me to use more than one manufactures lenses (the extreme difference between cine and photo lenses)

Please post your findings on what frame size your capturing. Also I might recommend that if the glue idea doesnt hold up with the longer lenses do what I did. Take a filter stacker and mount your lens mount to it. Drill a clean diameter hole in the filter stacker for the light to pass thru. Now you have the abilty to fit just about any lens you can think off on your adapter. Theres other things you can do too to add more features/abilities to a homemade adapter but the rest are just butter. Good job.

Hey check your fous marks to make sure you got it right. If your close you might be able to grind off one or two threads on one of your filter rings and you should be there.

Brett Erskine
Director of Photography
Premiere Visions
www.CinematographerReels.com

Thanks Brett!

That means a lot coming from the man who taught me (almost) everything I know ;)

I'm not sure how to measure exactly what the dimensions (in millimeters) are of the capture on the GG, but I did a test to show what the lens is seeing.

http://homepage.mac.com/dvx100/PhotoAlbum4.html

Brett,
Also, concerning the correctness of the distance from the GG to the lens and the markings on the lens, I'd say it's pretty damn close. I guess I just happened to find the magical number. You're absolutely right - if it's off by the tiniest bit, the lens will appear not to focus correctly. I found that by focusing on "infinity" I could estimate the length easier. If the image was sharp with the lens focused on infinity (say something across the street), all the numbers seemed to be accurate. But then again I haven't measured to be certain.

Brett -- Thank you for the tip. You are so right; I went back in and fine-tuned the distance to the ground glass, and it got sharper! The best part is that the threaded filter washers can be slowly threaded to achieve what I'm sure is a 1mm adjustment. Once the distance is achieved, tighten it up, and it works perfectly I also did this on the infinity setting.

I can't wait to put the anamorphic lens back on this fine tuned aldu35. I also built this with the condenser lens that you knew would work. It has a focal length of 1. The macro that I made before this was 'sub par'. I could not have made this without your optical skill ... the trial and error would have been endless!

I have a few questions:

1. A few times I have heard people say that the grain on the GG becomes pronounced around f4 and above. Is this f4 on the camcorder, or f4 on the SLR lens?

2. What is a "threaded filter washer"?

3. James, do you have a condenser that came in a 55mm filter ring, or did you rig that together somehow?

4. James, in the picture of your rig, the rings that are marked "spacers", are these just filters that you popped the glass out of, or what?

5. I have to imagine that all of you out there who ground your own glass have a bunch of Aluminum Oxide grit left over. Would anyone be willing to sell me what you have left for a percentage of what you paid? It just seems so wasteful to buy a bunch of this stuff, then only use just a little. I'd be happy to take it off your hands.

Thanks everybody.

Justin; I bought WAY to much aluminum oxide. I have WAO 5 micron, some 25 and some 9.

If anyone else in Canada is looking for some aluminum oxide I can sell some to you as well; I got hit with unexpected duties which equaled my purchase price when I bought this stuff, as it was shipped via FedEx from the USD. Wouldn't want that to happen to others as well.

----Is this f4 on the camcorder, or f4 on the SLR lens? -------

That'S F4 on the SLR.

Justin-

The condensor is a X1 macro 55mm. It seems to work. I still plan to eventually replace it with an actual PCX lens.

The other rings I'm referring to as "spacers" are $5 UV filters with the glass removed (I got a couple for free).

um...that's +1.

Porro Prisms are narrow right angle prisms used in pairs to make a system that erects and reverts an image from the objective lens of an optical system.

Some one know if porro prism act lick roof prism to revert image???

how to use ??? to "erects and reverts an image" ???
http://en.wikipedia.org/wiki/Porro_prism


link for porro prism maby "big" for for us
http://www.aosa.es/Ing/Catalogo/optica/prismas/Porro2Class.htm
http://www.aosa.es/Ing/Catalogo/optica/prismas/notpor.htm


and this look like p+S kit ;) ;)
http://hardinoptical.com/tvporro.html

Thanks everyone for answers to my questions.

Grain shows up at f4 on the SLR lens? What gives? It would make sense to me if the grain showed up when the camcorder was stopped down, but does anyone know why the grain shows up when the front lens is stopped down? I guess I have a lot more to learn about optics.

James:
I looked at the "Problem" page on your website. Did you ever figure out what was smearing the edge like that?

Ari:
Sounds like shipping across US-CAN border is too expensive. I hope someone can buy some of that off you to help offset your costs.

Anyone within the US have some left-over White Aluminum Oxide that they would like to part with? I would happily pay for the amount still in the container, and pay shipping and stuff like that. Or, I could pick it up if you are in my area. I'm in Olympia Washington, and I go to Seattle every week.

Justin-

I think the problem is with my SLR and not with any other part of my adapter. I took it all apart (again) and tested the image at various stages dismantled and I only see it after the lens is attached. Not sure if that's actually the problem though. It could be a problem with the adapter that's only apparent when the lens is attached! I haven't had the time to check it with another lens. And of course incorporating another lens will throw off the length of the adapter :(

I've seen this type problem to varying degrees before in images taken with other people's adapter.

Has this problem been dealt with before in this thread?

-J

Nice job James, and welcome to the 35 club

Hello everyone! Reading these threads and brainstorming this concept has been some of the most fun I've had with coming up with guerilla filming tactics.

I'm a little confused about one thing though. With my 35mm still camera, the distance of any lens I put on it is always the same distance to the film plane; no adjustments of the lens to film place distance need to be made by me to use that lens. But if I'm collecting my knowledge correctly, you guys are saying that lenses of different focal lengths will need to be distanced differently from the ground glass to obtain a clear projection? If this is so, why don't I have to do that on my 35mm slr? and does that mean there's no way of being able to use one build for all of my nikon lenses?

You're correct - the focal flange distance (the distance from the back of your SLR lens to the film) is the same for a particular camera body... which is why you can use any SLR lens which fits that body. The same is true for these adapters. You can build one adapter which will accept any of your Nikon lenses (which are for the same body style).

The focal length is hard to get exactly right, so many people building adapters have made this distance adjustable for fine tuning - or for the more adventurous, to support multiple body style lenses (Nikon and Canon for example). But for a particular body style, once its set it shouldn't change.

There has been a lot of discussion about the focal length of the condensor used. It doesn't seem to matter a ton because with a PCX condensor (flat one side, curved on the other), the flat side is right against the ground glass. If you've ever taken a regular magnifying glass or lens and looked through it at a piece of paper, you find that the closer you get the paper, the lower the magnification. When you're right on the paper, there's basically *no* magnification, which is what we want.

Now, this being said, the purpose of the condensor is to try and 'collect light'. We believe that the degree to which this is accomplished is a factor of the curvature of the lens. A long-focal length (very little curvature) doesn't collect as much light, but has less spherical abberation... and the inverse is true for a short-focal length. The ideal is right in the middle - collect as much as possible without curving up the edges. The general concensus is to use a focal length equal to the diameter of the lens - 52mm diameter/52mm focal length or thereabouts. But, to be honest, I don't think there have been a ton of experiments *other* than the diameter=focal length combo.

The key is that the condensor isn't really 'focusing' the light to a point, but collecting 'stray light' that wouldn't be in the direct path to the macro lens.

My two cents...

Hi everyone,

Glad I discovered this forum. I've been trying to design an adapter on and off for the last 18 months. Have recently switched to the DVX100 and, starting from scratch, will hopefully build something that doesn't have as much hotspot as my last attempt.

James, I think the edge blurring might be caused by the Hoyas. At such a close distance from the GG you are certainly using a significant portion (i.e. diameter) of the glass of both the Hoya diopters. Of course, lens quality decreases near the edges and having two of them back to back is sure to amplify any abberations the lens may have. Also, it sure would be nice if you didn't have to use 55mm lenses, but could use something larger.

I wish there was more selection in hi powered diopters, especially with a 72mm diameter. Century Optics makes two very low powered ones for the DVX100.

Still, your results are the best I've seen for the DVX100 so far. And Brett, your suggestions have been great.

Keep up the good work everyone. Hopefully I'll be able to contribute something useful.

Actually, James, I'm just wondering if the edge blurring would still occur if you were to take out the condensor from your adapter?

Thanks guys!

I've posted another test (along with captured still frames).
http://www.homepage.mac.com/dvx100/iMovieTheater6.html

Joel -
I first noticed the problem before I even incorporated the condensor. Though it seems logical that it is the (2) X10 Hoyas, from what I can tell they alone don't appear to be causing it. In fact I'll post an image to prove it ;) And I hope I'm wrong! I'm still looking at my SLR as the source of the problem. Don't know why it would exactly. And until I can disprove that assumption with another (good) lens, that's where I'm going to focus my attention...so-to-speak.