35mm adapter parts list

[Kyle Cutshaw]

Richard, are you seeing any vignetting with your adapter? Have you tried it on a camcorder with a 72mm lens?

[Kyle Edwards]

<<<-- Originally posted by Steev Dinkins : It is true, the distortion is an issue with James' design, and I have this issue as well with the adapter I have built that is modeled on his.

I'm using an XL2 which does allow for creative front end relay lens options. Has anyone built something with standard parts for the XL1/XL2 that is distortion free?

Here is example DV footage of where I'm at so far.

http://www.holyzoo.com/111/xl2/35mm/...er_V1_DV25.mov

For details on the what and the how:

http://www.holyzoo.com/zoo_updates.php -->>>

With both static adapters, wouldn't you have a screen of grain on your picture? Such as, a grain pattern that stays the same, I guess you can say an overlay.

[Aaron Shaw]

Kyle, yes you would. Limiting grain in static adapters has been a big topic of discussion which has no very easy solution.

What optical parts are you using in your adapters guys? I just ask because I assume the distortion comes from a cheap macro lens?

[Joshua Starnes]

Kyle,

It sounds like you're running into the wall all of us other XL1/XL2 users have hit. We've been trying for a while to build our own relay lens system so that you could mount the adaptor directly to the XL mount (without actually spending as much as a min35 costs) but so far, no luck.

[Jason Fox]

<<<-- Originally posted by Aaron Shaw : One more question: How many retaining rings did you end up using Richard?

Do T-mount adapters have the same type of threads? The only problem with the C-mount is that it limits the light that can pass through. -->>>

Aaron, any luck on figuring out if a T-mount adapter will work? I can hardly even find such an adapter (only one on B&H for Canon EOS). Also, those macro lenses I ordered from eBay are actually 55mm -- I ordered them when I was going to build James Webb's adapter. I only got a +1, +2 and +4 anyway. But I know you can find +10's fairly cheaply on eBay if you go 55mm. 72mm is also there, just a bit more and I don't think they're as high quality.

So how the heck do we attach the lens to the tube? Is there anyway to avoid going Richard's route and hacking up the c-mount adapter and gluing it to a step right? Will another lens brand fit better with an adapter? I just bought a Canon lens for testing, but it was only 20 bucks, so I don't mind getting something else if need be.

Fox

[Jason Fox]

<<<-- Originally posted by Fred Finn : I have some footage with this GG and Cnvx lens. I made the tube out of PVC.
http://hazardousproductions.com/films/chron_frd.mov
right click save link as.

I did have to use a macro on my gl-1. -->>>

Fred,

How did you mount the lens to the tube and what kind of lens did you use?

Fox

[Aaron Shaw]

Jason,

I found that it does indeed have threads. I do not know if it has the right thread pitch though to connect with other photographic items. This is what I do know:

"The thread used on T-mounts, referred to as the T-thread, is a metric thread 42mm diameter and having 0.75mm pitch. It is correctly written as "M42-.75". If you’re more comfortable with inches and TPI (threads per inch), the thread would be 1.654" in diameter and have 33.866 threads per inch. The inside diameter is typically 1.615"."

As for using a different lens: I don't think that will make much of a difference. I haven't experimented with it myself but pretty much all 35mm lenses are the same with only slight differences in the mounting mechanism. Nothing extreme enough to make much of a difference.

[Fred Finn]

<<<--

Fred,

How did you mount the lens to the tube and what kind of lens did you use?

Fox -->>>

Hey Jason,

I went a little unorthodox on this one. I took the whole 35mm lens apart. I stripped it of all non-essentials (focus ring f-stop ring). I used a rubber band to hold the aperture open all the way. The new lens was downsized in diameter quite a bit and fit nicely into the end of a piece of pvc. I used an adapter piece that fit a filter ring on the other end. I used hot glue around the perimeter to hold the lens on, then wrapped black electrical tape (very tightly like you see when you look at wires under the dash of your car) around the end of the lens and the pvc to block light and a backup for stability. I also painted the pvc black on the inside (flat) to prevent any reflection issues.

*edit I also tapered the end of the pvc slightly to allow the 35mm lens to slide into the pvc allowing for a really tight flush sitting seat.

[Jason Fox]

Fred,

I think I'll just have to give that a "holy frijoles" and leave it at that. Well, almost. How did you focus that thing? Distance from lens to the GG? Crazy, I say. Crazy.

Aaron, I'm trying to determine the thread pitch of standard filters/step-rings. I found one reference on B&H to .75, but have yet to determine if that's standard. The filter companies I've visited don't list anything.

I thinking you could hack up a camera or adapter to get the body mount ring and then attach that ring to a step-up ring. Not having either item at hand at the moment I'm not sure how that would work. I'm voting for duct tape.

Fox

[Giroud Francois]

yes , you should take care.
T-mount exists in both version, one with 0.75mm pitch and the other with 1.mm pitch.
I got this problem when going for M42 (and obviously finding adapter from other mounts to M42 is impossible, while every mount as an dapter to use M42).
So i switch to nikon mount for my next adapter.

[Aaron Shaw]

Does anyone know if the Nikon 6T/4T close up attachements are acrhomats? I seem to remember hearing this somewhere but I can't remember. If not it looks like I'll have to move up to a $119 Canon macro lens.

[Aaron Shaw]

Alright found the answer to my achromat question. Next question:

Will a power of 3 diopters be enough or should I spend extra and get a 10 diopter strength macro lens? I'm using the DVx100A.

I keep leaning towards the Nikon +3 but something inside keeps holding me back. I don't want to end up with too little power. I know that +10 seems to be what has been used on other projects but I wonder if that was utilizing the full zoom?

[Jason Fox]

Aaron -- don't yet know about the +10, but I did buy one of those cheaper 72mm ones off of eBay to test. I also have the equivalent of +7 in 55mm form that I will try as well. Should have everything but the +10 by this weekend. Still not sure how I'll hook up the lens, though. Grr. Arrg.

Fox

[Richard Mellor]

<<<-- Originally posted by Kyle Cutshaw : Richard, are you seeing any vignetting with your adapter? Have you tried it on a camcorder with a 72mm lens? -->>>



I have not tied it on a 72mm. I do not get vignetting . It will depend on the cameras close up zoom .It seems to vary
between cameras

[Jason Fox]

Okay, I have most of the parts now. The only thing I think I still need is the 10x macro I have on order. The 4+2+1 isn't cutting it. One question, though, how do I set the focal lenght between the 35mm lens and the GG? Do I make sure I can focus on it with the camera first and then adjust? I think I'm close just by looking at the adapter when it's off the camera, but can't tell for sure.

Also, I have an idea about attaching the lens to the ThorLabs tube -- take the set screws from the back of the C-mount adapter (remove the back, obviously), drill and thread holes in a 52mm to 58mm step-up ring and use the set screws to hold the C-mount to the ring. Worth a shot at least.

Fox