Aluminum tubing that has a big enough I.D. with a fine metric thread has been hard to find. Im sure they exist but as of yet I havent found ones that are ready made. What you can do is have someone take aluminum tubing stock and cut threads into them. Make sure you have enough threads to expand the difference between the flange focal length of still photo lens and motion picture lenses as it is greater than what a stepup ring can provide. Even better would be sometype of lens housing minus its optics or a adjustable length extention tube. Both would have to have large I.D.'s especially on the camera side of the GG.

Also your extra UV filter (the one you use to block the dirt from getting on your ground glass) should have a antireflection coating on it because it faces right at the ground glass.

-Brett Erskine

Does anyone know of a link where I can find out the actual inner (female part) and outer (male part) diameters of various step-up rings? The local stores are not too thrilled to open sealed step-up ring packages to let me measure them :).

Also, I've read a few recommendations where it's advised to place the condensor lens in front of the GG ( i.e., SLR Lens -> condensor -> GG ) and NOT behind it, to minimize reflections. Has anyone tried to compare these two cases in practice?

I've been trying to keep this project cheap, but I realize that I do need a closeup filter. Obviously, I need a two element solution to cut down on the chromatic aberration problem, so I think I've about decided on this:

http://www.bhphotovideo.com/bnh/controller/home?O=productlist&A=details&Q=&sku=77546&is=REG

Anyone else know of something cheaper? What about the Hoya filters...anyone using a 58mm achromatic diopter other than the Century Optics brand?

Thanks!

The +10 Hoya's are generally a better deal at about $70 but ideally you usually want to get a diopter no stronger than you need in order to avoid moving your GG back farther away from your camera to make up the difference. Getting the right kind for your camera will make sure your adapter is as physically small as possible in the end.

-Brett Erskine

Jonathon Wilson where are thoughs condenser FL numbers?

Dude - I"m still at work. I think I've been at my house for a total of like 6 hours total in the last three days. You'll get 'em once I actually see 'em :)

Brett: I found an old post where you had a link to some of the Hoyas, but the ones in that price range weren't two-element, where they? I probably looked at it wrong.

Also, what strength would you recommend for a Canon GL2?

Thanks!

Send me the link or check out the part number with Hoya. Since I have a DVX100 and not a GL2 I dont know. Im pretty sure the info as already been posted. Otherwise your going to have to go to your local camera shop and test diopters out yourself.

The problem is that I'm in south Mississippi. Not a high concentration of camera/video equipment suppliers here. I'd sure like being able to walk into a place with my camera and try stuff out, though.

Here is the link in question:
http://www.2filter.com/hoya/hoyacloseup07.html

My only option - the two-element adapter in 58mm size - only go up to +5, and are $111.63.

Frank, here's a good link for achromats:

http://www.angelfire.com/ca/erker/closeups.html

It also tells you how to calculate the focusing distance when adding a diopter, so you can figure out the lowest value that's useable with your camera. Like Brett says, go for the lowest value necessary to avoid spherical aberrations.

I appreciate that link, Roman! Looks like a lot of helpful info at the bottom of that page.

Thanks!

Frank I checked out your link. Thats the same price as I've seen for the Hoya +10 achromat macros but just call up the Filter Connection and ask to make sure.

Please bear with my ignorance about optics.
There is all this talk about FL, help clear a few things up for me.

SLR lens -> GG -> Condenser -> -> Macro -> DV

OK I know that FL is important here
SLR lens -FL> GG
so the image on the GG is in focus.

and I understand the basics about different color waves acting a little short or long in relation to each other.

But is FL important anywhere else in this setup

Maybe here
SLR lens -FL> GG -FL> Condenser -> -> Macro -> DV

or here
SLR lens -FL> GG -> Condenser -FL> -> Macro -> DV

Is the condenser flat side right up against the GG?

Will the Hoya +7 or +10 work as the condenser?

Thanks

John

<< But is FL important anywhere else in this setup >>
IMHO, no. As long as you can focus onto the GG image (with macro or without, depending on your camera), you're OK.

<< Is the condenser flat side right up against the GG? >>
IMHO, yes, but Alain had his condensor with convex side up against the GG.

<< Will the Hoya +7 or +10 work as the condenser? >>
Sounds like a great idea to me. The +10 diopter's focal length is 1000/10 = 100mm, which sounds about right, although I don't believe that condensor's FL is that important, since you put it right against the GG.

Some one have a idear which is the best fresnel lents to use .
I find few on edmund optics website
whit Effective Size diamater of 2" but different type:

IR fresnel
http://www.edmundoptics.com/IOD/DisplayProduct.cfm?Productid=2042

Aspherically Contoured Fresnel Lenses
http://www.edmundoptics.com/IOD/DisplayProduct.cfm?Productid=2039

PCX visible fresnel
http://www.edmundoptics.com/IOD/DisplayProduct.cfm?productid=2040

some one test both solution to avoid hot spot : frenel & condenser

some info best solution

last question..

some one test whit boss screen ???

Ciao

Read my previous post (RMPP) as to why no one is using fresnel lenses anymore and are looking at condensers.

My order of 1000 grit aluminum oxide arrived from The Rock Shed today.

I got a new piece of glass, made sure it was clean (and made sure the two oxide sizes didn't get mixed), cleaned the ground glass, and started grinding with the 1000 grit. Immediately I felt something bigger in the mix while grinding. Felt like a grain of sand or something. So I cleaned the surface and the ground glass and found some very noticeable cuts on the ground glass.
I started the whole process over, and repeated this four or five times. It seems that the 1000 grit oxide from the Rock Shed isn't pure 1000 grit. I haven't heard anyone else complain about this, but I thought I'd mention it. I had to go back over the glass with 600 grit to get rid of the scratches.

Brett: Thanks for checking that link out. I will give them a call and find out. Thanks!

Frank-
Have you tried Aluminum Oxide 9Y? Alain recommends it and from my research it seems to be the finest grit you can get. Anything finer actually polishes instead of creating a ground surface. Do a google search to find it.

Also Im using two UV filters that have a multicoat finish to reduce internal reflections inside my adapter housing. One UV is for the GG and the other is right behind the 35mm lens to seal the adapter from dirt getting on the GG and coming into focus. The coating may be over kill but when I saw the two filters facing eachother before the GG I thought there could be a possible reflection problem. Getting UV with multicoating in a 55mm size is hardly a big investment and at the very least worth the piece of mind. Make sure they also have the removeable retainer ring so you can take out the glass to grind it for your GG.

-Brett Erskine

Thanks, Brett! I'm going to check into that 9Y stuff now.

Yeah, I thought that was a good idea that you mentioned earlier about the 2 filters. I likely would not have thought about that reflection problem. Thanks!

,Frank

Rockshed grit worked just fine for me...

- jim

i just find a glass/mirror cutting workshop and asked a guy is there any possibility to use "1000" aluminium oxide in his workshop and make me a GG. no problem, since he is already making some matte glases for the kitchen/bathroom furniture. next day i received nice GG. (it's 52mm diameter from UV filter) deal was 5$. no scratches, nothing. maybe this is not proper way to do it (this is definitelly NOT a DoItYourself case), but it looks this will work for me. will check with the adapter any day...

filip

I've been messing around with the 1000 grit AO I got from the rock shed for about a week. I too experienced the "mysterious scratch" phenomenom early on. After some investigation, I don't believe the AO is the culprit. It is pilot error. You have to keep the grit well hydrated (lubricated) and you must constantly move the piece you're grinding around on the grinding surface. Here are some guidelines I follow now and I'm quite pleased with my results.

1. Minimum 8"x10" glass grinding surface (keep the glass filter moving to new areas of the grinding surface)
2. More water than you think and less AO (the AO should be suspended in the water on your Grinding surface, not a paste. There should be enough water for each grain of the AO to be seperated from its brothers)
3. Use light, even pressure for grinding (don't get into a hurry)
4. If you feel a change in the friction, STOP! ADD MORE WATER!
5. Wash away the used AO often and add fresh AO and water. (I think the waste glass is binding with the AO and is baically creating little bits of sand.)

I hope this saves someone some time.
I'm waiting for a set of experimental plano convex lenses to test with my static and dynamic adapters. I really like the way this adapter is shaping up.

Brett,
I'm looking to buy a DVX100A. Are you developing your adapter for the 100A or the 100? I understand that the "A" has a much shorter minimum focus. What strength diopter are you using? Thanks, Joe

Hi all,

Please note a new thread dedicated exclusively to Hi-Def Digital Cameras (not DV) with Aldu35 adapter.

It's here:

http://www.dvinfo.net/conf/showthread.php?s=&postid=154408#post154408

Very nice link for DoF

http://www.dof.pcraft.com/dof.cgi

i was wondering if i could purchase a custom Aldus35 off one of you experts!

Joe-
I have the DVX100 (not the A). With the DVX100-A better minimum focus you will only need about a +10 diopter for still lenses. Buy only ONE Hoya +10 achromat diopter. Your still going to need more than one diopter if you plan on using cine lenses. I havent done test with the DVX100A but if I had to guess right now I would say you need a total of about +13. Get the A if its about the same price. Should make your adapter just alittle bit smaller than with the regular DVX100.

-Brett

I was gonna put some footage up but I decided to screw up my GG, accidentaly broke it in half. Whats a good quick source for UV filters? BestBuy?

anyways...no footage :( but before I broke the GG the footage looked outstanding, I just HAD to try to get the GG finer...then broke it.


I havent been all-stop though. Here is what ive done in the meantime. I made this rail dealie., this thing is rock solid.

pic
http://aequantum.com/DSCF0003.JPG

John

The Century F to C adapters appear to be on back order probably due to demand from miniD35 enthusiasts. I will try the more expensive Nikon version that is still available.

some one try to grind direct one condenser lents ???

i mean

____________! condeser lents whit grind on flat size
____________v___macro
SLR lens ----> [) () ----> dv cam

JUSTE like Nikon type D focus screen

less stop lose one glass less

another question:

if i use condenser lents whit flat surface directed to SLR lens

BFL (back focal lenght) shut bee the same as SLR focal flange ???

see image at http://www.edmundoptics.com/IOD/DisplayProduct.cfm?productid=1747

I've been following this thread the past few days. This is amazing stuff going on. But I have one question. Is ground glass absolutely necessary? That is, is it an essential part of creating a DOF lens adapter or is it for aesthetic texture purposes only? I would love to get going on building one of my own but I'd prefer getting the cleanest image possible and adding grain/texture in post - the depth of field adapter being the only thing I care about. Is the ground glass essential? IF not, how would this affect the setup so far?


thanks for your time and commitment, and kudos to everyone.

If you actually had been following the thread carefully you'd know that the ground glass is the one part that this entire adaptor revolves around. It is because of the ground glass that we get such short depth of field. The image from the 35mm lens gets projects onto the ground glass and then this projection gets taped by your dv camera. Without the ground glass, the depth of field we are attempting to get with this adaptor would be lost.

This may kick off some debate as I know that the working theory is that you need the ground glass... but I, for one, think that you could do it without the GG, but you would need a relay lens in its place.

In the 80's Panavision did exactly this with their first Panacam EF cameras... they took Panavision 35mm Cine lenses and projected the image from them onto a 2/3" tube. To accomplish this with the same DoF and image characteristics as the 35mm lens, they just had a relay lens which changes the image size from the 27mm diagonal of a 35mm film plane down to the 11mm diagonal.

As I understand it, they stopped making these because the abberations created by the relay lens become unacceptable at high-resolutions (like HD), but were perfectly acceptable for standard resolutions. I'm not sure where this stands by today's standards of optics manufacture.

I've got a couple of bi-convex lenses (curved outwards on both sides) lying around. I held my SLR up and positioned the bi-convex lens behind it at about focal flange distance - looking into this at the right angle, and from the right distance, I see a big bright fat inverted image. Seems like it should work.

Others?

--- references:
http://www.dvinfo.net/dv-l/869.htm (search for Panacam)

http://www.cinematography.net/[cml-hdtv]%20Cine%20lenses%20on%2023%20HD%20CCD%20cameras.htm (no real resolution, but an interesting discussion)

that was my intention to have the condenser lens acting as the gg until i see the result given wth the gg and the condenser with the flat side towards the video lens (no vignetting) from Alain.
as i got only one lens for instance, i would be happy to hear what is the result with a condenser lens that is reversed.

<<<-- Originally posted by John Gaspain :
I havent been all-stop though. Here is what ive done in the meantime. I made this rail dealie., this thing is rock solid.

pic
http://aequantum.com/DSCF0003.JPG

John -->>>

I like the look of the adapter, what materials did you use? That doesn't look like the PVC pipe they sell @ my home depot

about relay lens, you skip the most important of your references.
quote:
In conclusion, even an excellent cine lens, combined with a theoretically perfect relay lens, will produce a relatively poor image on a 2/3" CCD camera when compared to even an average quality video lens.

Yes, but if you continue reading that article, the guy in the very next post completely disagrees - and so on and so on - back and forth. This is what I meant by "no real resolution"

Unfortunately, none of us (lurkers notwithstanding) are qualified to understand the optics of this. I am continuing with the ground glass idea because its easy and works pretty well. I just threw out the thought and links because I don't believe its set in stone that you couldn't make it work without the GG if you had a good understanding of optics and a very high-quality relay lens. I have neither, so its GG for me :)

Just a'waitin' for my grit. (there's a tune in there somewhere).

Any lurking optical-degree-holders care to join in the fray and set us straight?

<<<-- Originally posted by Ari Shomair : <<<-- Originally posted by John Gaspain :
I havent been all-stop though. Here is what ive done in the meantime. I made this rail dealie., this thing is rock solid.

pic
http://aequantum.com/DSCF0003.JPG

John -->>>

I like the look of the adapter, what materials did you use? That doesn't look like the PVC pipe they sell @ my home depot -->>>

Its a Lowes model :)

I don't know if this has been brought up before, but I found a source for 1200 Grit Aluminum oxide powder -
http://www.whiteabrasives.com/aluminum_oxide.htm .

Only problem is they sell in minimum quantitys of 10 pounds. Are there 9 of you out there which want to split some with me? Email me if interested, or if you know a place to get smaller quantities.

http://www.gotgrit.com/default.php/cPath/2_7 has aluminum oxide powder that sells by the 1/4 lb. According to this chart http://www.facetingmachines.com/grit-mesh-micron.shtml, 1200 grit is the equivalent of 15 micron. Dick Dokas's article on making your own ground glass (http://www.phototechmag.com/previous-articles/2003/mj-dokas/dokas.html) speaks of going down to 3 micron/8000 grit. Gotgrit doesn't sell that small, but they do have 5 micron/4500 grit. I plan on buying some from here soon.

WHIT CANON XL1 CAMERA

YOU REMOVE THE LENS

iF YOU PUTT VERY STRONG CONDENSER LENS (after GG) THAT CONCENTER LIGHT RAY DIRECT IN TO 1/3 " CCD SIZE ????

what about this ????

Nicholi-
I know there is a point when choosing the right grit that if you using something thats TOO FINE it acts as a polisher and not a grinder. In other words it wont make ground glass. Im not totally certain what that grit number because I keep getting conflicting info on this thread. But I can tell you alot of the suppliers on the net seem to put the cut off point just after 9 microns. For this reason I myself decided to use 9 micron Aluminum Oxide powder.

A interesting note is Canon uses lasers to etch/pitt their ground glass for some of their still cameras. The process promises not only finer grain ground glass but brighter as well. The problem is that their GG always seems to have some type of focusing assist marks on them making them useless for our needs. Still looking though.

-Brett Erskine

Brett this link about what you hare talking

All mate GG is type C, J, K

look
[url]http://www.mir.com.my/rb/photography/hardwares/classics/canonf1n/metering/screens/screens.htm

I say the best part of this thread is all of the great, hard to find links. Thanks to Nicholi for the gotgrit link.

Brett, did you notice a great difference in performance using the 9micron GG vs. the 1000 grit GG? I've been pleased with the GG I created with 1000 grit but am always striving for more.

One more thing, Paolo Rudelli posed a great question earlier today and I would love to read a respnse from someone who's already corrected for hotspotting and vignetting. (I'm still waiting for condenser lenses to come in so I can experiment)


My questions are similar to his:
1. has anyone tried to grind the flat side of the condenser lens?How did it work?
2. has anyone tried to place the condenser between the SLR lens and the GG? It would be great if anyone who has already done condenser placement experimentation to share their findings and the steps taken to get their results.
If it has already been posted and I simply missed it, could someone please post a link? Thanks, Joe

I've got a variety of cheap lenses that I got from American Science Supply. Of interest are:

1) A larger-than-35mm-film-size diameter biconvex lens with a large radius (it's a fairly thin lens, about 4mm at its thickest point).

2) A larger-than-35mm-film-size diameter biconvex lens with a smaller radius (bigger curves). Probably 15-20mm at the thick part. However, the 'thin part' is still a good 5mm across, feeling like two plano-convex lenses which have been put back-to-back - but I can't see any seam.

3) A larger-than 35-mm-film-size diameter biconvex lens with a large difference in the two sides... One side is slightly convex - but nearly flat - the other has a serious curve. This is about the closest thing I have to a usable single-element condenser.

4) A smaller plano-convex lens - truly flat on one side, curved on the other. Too small to use though.

5) A rectangular exactly-the-same-size-as-35mm-film plano-convex that was the condenser from my AE-1. Very thin at its thickest point - probably 3mm.

6) A couple of small achromats. These seem like plano convex in their entirety because their flat on one side and curve out on the other - but they are actually two elements cemented together - a plano convex cemented into a concave/convex lense, like this:

cc + pc achromat
(( + (| = (((|



The tough part is I haven't yet come up with a good way to mount these odd-sized lenses such that I can get them into my actual PVC adapter assembly. This makes it very difficult to guage their effects on vignetting, because this really only gets visible when you're all locked down and light-tight. The best I've been able to do is hold them up in some open-air experiments. ALL lenses seem to significantly brighten the image on my GG, regardless of whether they are between the SLR and the GG, or between the GG and the macro - and the direction (curved vs. flat) also doesn't seem to affect brightness at all - they're all the same.

Any tips from you builders out there on how to get one of these held in place and locked into a PVC assembly near my GG? I'll be happy to measure the focal lengths, and radii more accurately, but frankly, without some measure of the difference in their effects in a real 'lightless' environment that displays various amounts of vignetting, it doesn't seem like it will help much.

Additionally, I'm still waiting for my real grit to show up, so I have some ground glass I got from American Scientific Supply - which works and is fairly even, but has large visible grain. I also have my quick/ugly, but mountable GG with I made with (choke) sandpaper and steel wool. I also see an image - but it has large scratches and shows even more vignetting due to the unnevenness of the surface.

In short - I need to complete my real ground glass and figure out a way to mount these odd-shaped condensers before I can do any definitive testing. I'd love to hear mounting suggestions for the condensers.

Jonathon Wilson-
While you wait to get better GG you can fake a lightless situation and swap out the different condensers but simply shuting off all the lights in the room your in at night and point the 35mm lens thru the crack of a door to another room that has all of its lights on. If its day time try cuting a small hole in a thick black plastic trash bag(s) and put your 35mm lens through it - making sure to use tape to seal any possible light leaks around the outside of the lens. Get your head inside the bad (both like a large format photographer and...a idiot) and test your GG/Condensers.

As far as the Canon laser etched GG the other problem is that I believe they decided to have the GG and the fresnel on opposite sides of the same piece of glass so - no good.

-Brett Erskine

Good idea Brett, sounds fun climbing into a hefty bag.

I'll try that and report back... Probably not until at least tomorrow night - looks like I'm pulling yet another all-nighter at work.

Joe Holt: Thanks for that advice! Yep, I played around with it some more and it seems to be working better now. When it's just a thin layer of primarily water with an even, thin spread of aluminum oxide, that seems to work best.

I took it out for a test yesterday (we're having some beautiful weather down here) and was impressed with the results - especially since I don't have an achromatic diopter or a condenser.

Basically, I have the ground glass, 35mm lens, and a regular curved lens, in this arrangement:


35mm Lens -----> Ground Glass -----> Lens ------> Canon GL2

The regular lens is right against the back side of the ground glass, with the outwardly-curved side facing the camera. This cuts down on the hot spot I was getting with just a 35mm lens and ground glass.

I will try to get some images up in the next couple of days.

,Frank

I have successfully made an XL1/XL1s version! I haven't even begun to perfect the design or address other simple issues-but still, lacking these improvements-my images are, easily, as good as, or superior to what I have seen so far.

All I can say is wow!!!
D

Sounds exciting, Dino! Congratulations! It'd be nice to see some of your footage if you can find a place to put it.