Working DIY adapter
 

I have some test images from my 35mm adapter, It's a static adapter and I used it with my Canon XM-2. I think it's works really good but I really would like some feedback on it!

http://www.kokokaka.com/35mm ( You need flash 8 )

Where is it on the site?

Click on the link "...sample footage"

The skateboard clip is definitely the most effective small-DOV footage I've seen on this board. At first I thought you used Dan's (God all-)Mighty FOLLOW FOCUS, but some slight shakes on the end of a focus gave it away.

What frame rate is it? Or is it a built-in flicker effect? Anyway, it looks very good and reminds us what the heck we are doing here...

Damn, that's good.

Jimmy,

Impressive. Parts list?

Josh

Ok, here is the parts:

thorlabs.com:
1p 29.50 EUR SM2L20 Stackable Lens Tube
2p 9 EUR SM2RR Retaining Ring For 2" Optics

optisigma
1p 26,20 EUR Groundglass, p/n 099-0160
1p 35,20 EUR BK-7 Plano Convex Lenses 011-2870


1p Macrolens
1p Stepupring


Nikon Lens > Nikon f-mount > ground glass > Plano Convex Lens > step up ring > +4 macro lens > Camera

I build the f-mount with an old f-mount from a camera and a 52mm filterring, glued toghether.

I'm waiting for Nikon BR-3 adapter to use instead. Everything cost me about $200-250 excluding Nikon lenses. I also need a better macrolens. Anyone knows where I can find a +10 diopter?

All clips are CC but no other effects. It's 25fps and I think the flicker comes from flash. The focus is set manually, it's difficult with the SLR lenses but with some practise it works quite well.

Jimmy,

How did you light for the side view shot of the camcorder with adapter? Did you use a white background or was the background purely photoshopped out? It looks very nice.

How about a +7 diopter? Ben winter is very pleased with the one from Century Optics

http://www.dvinfo.net/conf/showpost....3&postcount=17

Thank you for the BR3 tip and all the other parts listed. I totally agree with what Oscar said a couple of posts earlier.

I also endorse the 7+ Century Optics Achromatic dioptre.

Jimmy,

Looks quite normal, but you are getting very good results. Do you need a spanner wrench to adjust those retaining rings?

Some have used the Hoya +10 macro lens.

Josh

No, I don't have any spanner wrench, I used a nail and my fingers.

Looks Great....
 

How's that tutorial coming along?

Also, noticed that your first clip (first version of the adapter) seems to be more sharper that your two newer clips (which seem to be a bit more hazy, but still quiet nice). Any guess why? (or is it just my monitor?)

I'm ordering the parts, but will try some diffrent options based on other threads,
such as adding a second pcx to make a sandwich - (| || |) - (pcx, gg, pcx) and adding another inch between the gg and the lens.

In your design, how is your pcx install || (| or || |) (curved side facing in or out)?

Thanks

I have no condensorlenses in the first clip but i had some vignetting problems then. I put the lenses like this:

|| |) - > Camera

I'm going to build the new version of the adapter during christmas and will try some different options. I haven't read about the option you are going to build, it would be nice to see some examples later!

> Bill porter: How did you light for the side view shot of the camcorder with adapter?

I have a white background and a 1000w lamp. Then I used some curves to get better contrast in the picture.

Some new parts have arrived, going to build the new version before christmas!

Thanks! It's a very nice looking image. :)

Just a reminder that instead of using the ground glass and condenser, you can buy the Nikon D Screen, which has less grain and a built-in condenser, from bhphotovideo.com and put it in this type of adapter by glueing it into a retaining ring--it fits perfectly:

http://www.astronautradiomusic.com/nikonscreen1.jpg

So that is the Nikon D screen glued into one of these? http://thorlabs.com/NewGroupPage9.cf...tGroup_ID=1535
Is that the tube for 2" optics?

I have a question for Jimmy, the gg and the convex lens are fit inside the tube? Or are they mounted on the outside? Would it be possible for your to post a closeup picture of the adapter by itself. I really enjoyed the videos from your site and would like to emulate the effect you have created. Any help would be appreciated.

To answer all of your questions, yes it's glued into one of those retaining rings for the 2" 52mm optics tube. The GG and convex lens are mounted inside the tube, sandwiched between two retaining rings.

Thanks Ben! I will try to take some photos when I start building my next version of the adapter. Maybe during the week...but I have to buy some christmas presents to!

That'd be wonderful. I would love to see some photos.

Thanks for the clarification. Another question, is there a forumla to determine the proper spacing between the gg, convex lens, and camera or is it simply guesswork?

I'm sorry if I seem probing but you just place the gg and convex lenses right next to each other within the optic tube, touching? I can wait until Jimmy posts his photos to find out but I'm trying to figure out exactly how to do this.

I have a retainingring between the gg and the planoconvex lens (about 2mm). I will try to move the plaoconvex lens about 2 cm from the gg, when I tried this by just holding the lenses I noticed this give me a straight picture over the whole gg. Thers is different distance between difrent planoconvex lenses. Mine have a focal length of 70mm, I don't know the relationship between focallength and the best distance from the gg, I think you have to use your eye to decide.

Jimmy,
You may want to read my thread here: http://www.dvinfo.net/conf/showthread.php?t=50884

One thing about moving the PCX lens away from the GG is you start to get more chromatic aberation, as the 35mm frame is magnified and gets closer to the edge of the PCX lens.

Ben,

What are you finding to be a better device - the Letus Mod, or the static adapter with the thorlabs that you created?

I'm finding that the Optosigma works fine, but only in very intense light situations: you'd be restricted to shooting outdoors or with good lighting inside. The Letus35 modified with more battery power works very, very well in all situations. When I had my optosigma static adapter based on Mellor's design, the PCXL was right up against the ground glass touching it with no space inbetween. It gave me some distortion around the edges, which was expected but easy to zoom away from. Chromatic abberation was minimal and there was zero vignetting, of course. Like I said, the only other hurdle is grain which can be eliminated with enough light, and if you so choose you should sandwich two of them together so it diffuses enough.

Please check my thread here for my results with my old optosigma static adapter:

http://www.dvinfo.net/conf/showthread.php?t=47625


Video at the bottom seems to have been taken off the server, sorry

Hi everyone !

I am new here , I've been following lots of threads and its been very exiting. Also it seems lots of people decided to buy ready made adapters , I am glad to see people enjoying designing homemade 35mm adapter.

Jimmy > Very nice design , Good footage too !
I am impressed with the quality you've got so far ,can't wait for the new version.

I am starting my kit soon hopefully and I've seen you're using the stackable lens tube, I am not sure how this work though... Do you have a standard length size for it ?
I understand you can setup the retaining rings inside so you can adjust the Flange Focal Length as desire but after you have the 'left over' of the tube to deal with :( if its too long it might create some problem no ?
Not sure I made my self clear so let me know ;)

BTW , I checked your website and Already knew lots of those sites, just didn't know it was you > Well done man ;)

I think Jimmy is using the Thorlabs tube, but not sure of the length (he'll tell us once he finishes the new version of the adapter). A lot of people are building it based on the Richard Mellor design which uses a 2" tube.

http://www.dvinfo.net/conf/showpost....23&postcount=1

The G35 adapter "tube" is 5" long. This means that the "left over" space isn't a problem. In fact, after quite some poking around on the forums, it seems that moving the gg further away from the camcorder lens helps with sharpness and barrel distortion.

Great clips. My favorite was the second one. I noticed that you used a condenser with an FL of 70mm. Can you comment on why you chose that because some folks are recommending FL of 85mm and all the way to 160mm(Wayne Kinney)? Also, Andy Gordon mentions that "70 or 80 between the GG and SLR lens caused the edges of the image to blur".

And Ben, I am having hard time figuring out your stance on the Nikon D focusing screen. On the 17th, you posted that Nikon D has "less grain and a built-in condenser" then GG(Are you referring to Optosigma?). On the the 19th(In a different thread http://www.dvinfo.net/conf/showthread.php?t=56393), you said that you would only use Nikon D in the non-static solution. I am confused.

I was referring more to my personal situation, in that I own a Letus35 and if I had a Nikon D screen I'd just swap it out with the GG in the Letus since it's basically the same size. I also have gripes with the Nikon D screen getting major grain problems at high aperture settings. At 1.4 though, I think it beats out the Optosigma glass.

Ben, thank you for clarifying. I myself have 50/2.0 lense and am torn between using the optosigma+condenser or Nikon D screen. The latter is ofcourse a cheaper solution as it already includes the condenser. Ben, do you think Nikon D is better in terms of performance per dollar in my case?

I think so, although there was someone else (can't remember who) who said they couldn't stand the grain on the Nikon D. To me, it's virtually grainless, which makes sense since that's how it was designed, as a focusing screen for astrophotography. Go figure.

Thanks Ben.

Optosigma:5 ------Nikon:6

Its funny how each night you leave this forum convinced that you figured this whole apparatus and have an exact list of parts.
But then.....
.....you wake up and read that someone has tested your design and concluded that it was junk. Back to the drawing board. And its like that every night...Brutal.

Ok, I have done some more test now and its getting better! I have a new f-mount which is perfect and I moved the planoconvex lens from the gg about 16mm and it gaved me a more straight picture and I have to zoom in less than before.

New Parts:
Nikon BR-3 Adapterring
Thorlabs Coupler ring SM2T2

I tried with two planoconvex lenses but I don't like to have any extra lenses between the lens and the gg because it change the focallength of the 35mm lens.

> I noticed that you used a condenser with an FL of 70mm.

I haven't tried any other FL of the lens but I think a short FL requires less length of the adapter. That gives less loss of light and a smaller adapter. I don't have any abberation problems with it.

I will try to post some pictures on thursday!

With the Nikon BR-3, how much did it off set your the distance of your gg?

The nikon BR-3 adapter adds 16mm and then I have a coupler ring between the adapter and the tube which adds between 5-15mm. I can adjust the coupler ring to easier set the right distance between the groundglass and the lens. It's a lot easier to adjust the distance now instead of moving the groundglass. I used the extra space to move the planoconvex lens 16mm from the groundglass which gave me a much better image. I also got my Century Optics +7 diopter today and I'm going to do some new tests after newyear, posting new images then!

Jimmy, I got the Nikon BR-3 on eBay for just 10 Euro (plus 6 euros S/H from France).
I've a problem with the Thorlab tube + the 2 rings (50 USD) because the shipping cost from US to Italy, where I am, is more then 67 USD.
Please, where do you get them.

What is the exact item number for the Nikon D diffusion screen, I keep getting all sorts of results on Ebay, like type E and other selections; would an F3 of F6 be recommended as the ground glass? i'm a little confused.....

Rene,
The one that you are looking for is F3 Type D Focusing screen. Thats the one without markers. I was not able to find any online for under 50 bucks though. I did see F6 one and they are supposedly better in terms of brightness but they are also a little larger so I dont think they will fit into a thorlabs tube. If you are not using the thorlabs, F6 screen should be a good choice but I think their marking types are different so the Type D for F6 is NOT clear. I think Type B is clear for F6's but I am not 100% sure. Here are some links.

http://www.mir.com.my/rb/photography...3ver2/screens/
http://www.mir.com.my/rb/photography...eens/index.htm
http://www.astropix.com/HTML/I_ASTRO...0301/I0301.HTM

Thanks, Dmitriy! I am using a 55mm ring and spacers so I think I will be using the bigger screen. Thanks again!