35mm Adapter Static Aldu35 - Page 44 at DVinfo.net

Go Back   DV Info Net > Special Interest Areas > Alternative Imaging Methods

Alternative Imaging Methods
DV Info Net is the birthplace of all 35mm adapters.


Reply
 
Thread Tools Search this Thread
Old April 7th, 2004, 01:32 PM   #646
Regular Crew
 
Join Date: Sep 2003
Location: Los Angeles, CA
Posts: 121
Nico's Post

In reference to the post about the slide adaptor at:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3807276418&category=29964

There seem to be a lot of different versions of this item. This one in particular seems to have some sort of condensor lens on the end of it.

As long as that was, and it worked out, wouldn't one only need to build an adapter to the front of that so that a 35mm lens could be mounted and project on its diffusion screen?

Thoughts?
Eric MacIver is offline   Reply With Quote
Old April 8th, 2004, 09:24 AM   #647
Major Player
 
Join Date: Aug 2003
Location: Poplarville, MS
Posts: 453
cerium oxide

I just wanted to let you guys know that I went ahead and tried the cerium oxide. (My glass was first ground with 600 grit and then 5 micron white aluminum oxide.)

I felt pretty sure that it would polish the glass, but I wanted to really see what would happen.

Anyhow, grinding with the cerium oxide is difficult. (A lot of catchy friction going on.) After a while, I did notice that I was getting a polished surface, so I went back and re-ground with the 5 micron.

I still get grain with any AO I have tried. I can turn down the sharpness on my GL2, which helps, but the image becomes a little too soft.

Now I'm thinking that microcrystalline is the way to go.

,Frank
Frank Ladner is offline   Reply With Quote
Old April 9th, 2004, 12:55 AM   #649
Regular Crew
 
Join Date: Dec 2003
Location: Sulphur, LA
Posts: 61
Acid Etching

I'm a Chemist,

I believe in better living through Chemistry and offhand believe this would produce better results than a mechanical method of making gg....

BUT

Messing with fluoride can be dangerous. You'll be making hydrofluoric acid and it can not only etch glass, it can do really wicked things to your bones. HF can be absorbed through your skin to attack underlying tissues and exposure at low concentrations may not be immediately evident it may take hourse befor you notice you have a real problem. I also understand that it takes very special medical attention to treat a victim.

HF exposure can lead to a very painful death.

If I were going to do this first I'd read the Material Safety Data Sheet for HF

http://www.chem.purdue.edu/chemsafety/Equip/hfmsds.pdf


If the MSDS doesn't scare you away (it should) I'd also want a little more detailed recipe. For example, what order should you add the ingredients? Don't do it by order of occurance in the list!. You should add acid to water. Then I'd add the KF last.

I'd also want to know if there is a commercial preparations available at low concentrations instead of making your own. You probably won't save much money over making up a batch yourself. You'll have less waste, and just dumping your left over chemicals makes you a criminal in some places, not to mention stupid, irresponsible etc. Also a commercial preparation will have its own MSDS sheet and will give you a better idea of just how hazardous the preparation is at the concentration you wish to use it.


KF is chemically similar to NaF, the sodium monofluoride you'll see on your toothpast label. The NaFl you have in your toothpast is fairly dilute, here you'll be using the concentrated chemical.

So in other words, don't make your own etchant. Buy a commercial solution and carefully use it as the mfg. recommends.
James Ball is offline   Reply With Quote
Old April 9th, 2004, 02:07 PM   #650
Regular Crew
 
Join Date: Feb 2004
Location: Sylva, North Carolina
Posts: 153
Some grabs

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
Joe Holt is offline   Reply With Quote
Old April 9th, 2004, 02:07 PM   #651
Regular Crew
 
Join Date: Feb 2004
Location: Sylva, North Carolina
Posts: 153
Some grabs

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
Joe Holt is offline   Reply With Quote
Old April 9th, 2004, 02:26 PM   #652
Regular Crew
 
Join Date: Mar 2004
Location: Milan-Berlin-Paris-Bruxelles
Posts: 26
impressiv

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
Paolo Rudelli is offline   Reply With Quote
Old April 9th, 2004, 02:54 PM   #653
Major Player
 
Join Date: Dec 2003
Location: warsaw, poland
Posts: 440
to joe

joe,

what kind of camera you are using?

filip
Filip Kovcin is offline   Reply With Quote
Old April 9th, 2004, 03:07 PM   #654
Regular Crew
 
Join Date: Feb 2004
Location: Austin, TX
Posts: 182
Wow Joe, those looked great - very very little grain in your GG.
Jonathon Wilson is offline   Reply With Quote
Old April 9th, 2004, 04:03 PM   #655
Major Player
 
Join Date: Jun 2003
Location: Oklahoma City, OK
Posts: 389
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).
__________________
Nicholi Brossia
Nicholi Brossia is offline   Reply With Quote
Old April 9th, 2004, 04:28 PM   #656
Major Player
 
Join Date: Aug 2003
Location: Poplarville, MS
Posts: 453
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!
Frank Ladner is offline   Reply With Quote
Old April 9th, 2004, 05:08 PM   #657
Regular Crew
 
Join Date: Jan 2004
Location: Montreal Canada
Posts: 86
Joe Holt

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
__________________
http://www.kheops-tech.com/~ad3d/
Alain Dumais is offline   Reply With Quote
Old April 9th, 2004, 11:34 PM   #658
Regular Crew
 
Join Date: Feb 2004
Location: Sylva, North Carolina
Posts: 153
Thanks for the feedback

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 Holt is offline   Reply With Quote
Old April 10th, 2004, 12:14 AM   #659
Major Player
 
Join Date: Aug 2003
Location: Poplarville, MS
Posts: 453
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
Frank Ladner is offline   Reply With Quote
Old April 10th, 2004, 04:32 PM   #660
Regular Crew
 
Join Date: Dec 2003
Location: Sulphur, LA
Posts: 61
post production removal of hotspot

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.
James Ball is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Special Interest Areas > Alternative Imaging Methods

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 05:40 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network