Adding an objective to a Canon T5i

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mawyatt
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Post by mawyatt »

bendecamp wrote:Yes, it's the gold one. I bought the adaptor from RAF camera to fit the objective on the end of a 100mm macro. So I already own the flat adaptor, and might not need the RMS, if I can figure out how to step down from 67mm to the extension tubes...

Yes, I thought it was off by a fraction of a mm, it was lining up exactly with the threads but they wouldn't screw in. .25mm difference. My plan was to use both the bellows WITH the extension tubes, to have control over magnification, more so projecting the image to the perfect size on the sensor... maybe that's overkill though.
If you plan on using the Raynox as a tube lens mentioned, it might be easier to build the entire lens assembly with extension tubes. Many of us have done this and the configuration seems to work well. If you decide this route I would recommend the 52mm.

Mike

rjlittlefield
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Post by rjlittlefield »

bendecamp wrote:http://www.amazon.com/M25x0-75-RMS-thre ... mm+adapter

That looks reasonable?
That adapter will make an MRL00102 objective screw into an RMS socket.

Whether that's reasonable depends on what else you have and how you plan to fit it all together. It's not a configuration that I've ever used.

--Rik

bendecamp
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Post by bendecamp »

mawyatt wrote:
bendecamp wrote:Yes, it's the gold one. I bought the adaptor from RAF camera to fit the objective on the end of a 100mm macro. So I already own the flat adaptor, and might not need the RMS, if I can figure out how to step down from 67mm to the extension tubes...

Yes, I thought it was off by a fraction of a mm, it was lining up exactly with the threads but they wouldn't screw in. .25mm difference. My plan was to use both the bellows WITH the extension tubes, to have control over magnification, more so projecting the image to the perfect size on the sensor... maybe that's overkill though.
If you plan on using the Raynox as a tube lens mentioned, it might be easier to build the entire lens assembly with extension tubes. Many of us have done this and the configuration seems to work well. If you decide this route I would recommend the 52mm.

Mike
I agree, but on one side of the bellows I'd have the lens assembly, and I'd have the camera move "backwards" where the bellows is at a fixed point, effectively enlarging the image onto the sensor. I had this setup with my other rig, and it worked well. In hindsight, I think it was self-defeating because I was changing the distance between the optics, and the sensor. Where I should only change the microscope objective to gain magnification. Otherwise, I'll keep backing up till I cross my front lawn.

Rik, I also own the original RAF adapter, which I suppose could use some step down rings to size down to the Raynox threads...

The goal is to be simple, easy, and fast. I just want to get shooting already! Thanks guys.

All Ex
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Post by All Ex »

As soon as I`ve decided to make the tube with the Raynox DCR-250 I have some questions and I decided to post them here :
  1. I have a D800 and the initial adaptor (Nikon F mount to M42) has a glass on it, since it is not a quality one and it will decrease the quality of the image, has anybody come with a solution on this?
    [Perhaps a quality adapter with a proper glass (I know that it is necessary in the accomplishment of the infinity focus and since we have an infinity objective it becomes essential) in case you have found something can you provide as with a link ?]
  2. As the tube lens acts like an 125mm one (if I get it write) should I expect the same results in a Nikon CF Plan 20X/0.4 inf/0 BD ELWD.
  3. As I have a Nikon the distance between the sensor and the mount of the camera is different than in the Canon body. Is there a way (function or something) to calculate the space between the sensor and the reversed Reynox?
Thank you,
All--Ex
My YouTube initial video

mawyatt
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Post by mawyatt »

All Ex wrote:As soon as I`ve decided to make the tube with the Raynox DCR-250 I have some questions and I decided to post them here :
  1. I have a D800 and the initial adaptor (Nikon F mount to M42) has a glass on it, since it is not a quality one and it will decrease the quality of the image, has anybody come with a solution on this?
    [Perhaps a quality adapter with a proper glass (I know that it is necessary in the accomplishment of the infinity focus and since we have an infinity objective it becomes essential) in case you have found something can you provide as with a link ?]
  2. As the tube lens acts like an 125mm one (if I get it write) should I expect the same results in a Nikon CF Plan 20X/0.4 inf/0 BD ELWD.
  3. As I have a Nikon the distance between the sensor and the mount of the camera is different than in the Canon body. Is there a way (function or something) to calculate the space between the sensor and the reversed Reynox?
Thank you,
Don't use the Nikon F adapters with glass or without, get the BR2A eqv from eBay ($25). The cheaper F adapters are not very sturdy, but the BR2A is a reversing lens adapter with 52mm threads and very sturdy. This gives you a direct 52mm for the extension tubes. This is what I use.

Chris has a great method for setting the length with the tube lenses, so I'll let him describe this.

Don't know how the Raynox 250 will work with Nikon objectives. I have only used Raynox 250 with Mitutoyo 5X (3.1X) reversed, have not tried 10X or 20X yet. With 5X Mit and Raynox 250 this combo works well.

Distance to sensor surface from F mount on Nikon is different than Canon. Nikon has a symbol O with line thru it on top of D800, this is where the sensor plane is. Think it's about 46mm, but not sure. You should Google or check your manual.

Best,

Mike

All Ex
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Post by All Ex »

Sorry but there is a problem with the youtube notifications, I have though seen your message in my cell and I spotted it through the forum.
Thank you for the BR2A recommendation, I`ll search it but I`ll need an extra adapter 52 to 42, you see I`ve already have the 42mm tubes.
In that old thread I thing Rik is using a Nikon objective. I have a very good 10X Nikon objective that it`s doing fine my question was about the20X one.
The distance on my camera is 46.5 mm ( I think it is called something like parfocal distance, I`m not sure though) I know that it is different in Canon, my question is about the space between the sensor and the reversed Raynox.

Thanks for your reply Mike,
have a nice remaining summer,

P.S.
Sorry about the parfocal distance that it is sown here:

Image
The source image is from olympus-ims.com

I can`t recall the name of that...
I looked it out and according to Chris R it is caled flange focal distance.
Last edited by All Ex on Fri Sep 02, 2016 10:56 am, edited 1 time in total.
All--Ex
My YouTube initial video

paleblue
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Post by paleblue »

rjlittlefield wrote: No -- vignetting is always caused by too much separation, not too little. The problem with some telephotos is that even zero separation is too much, because the telephoto is designed to take its corner rays only from the edge of its front element, not from the center.
--Rik
Rik, I'm new to this (my lens is being shipped right now) and confused. If the objective you're using is infinity corrected, then isn't all the light hitting the lens tube parallel? How can the distance between the lens tube and objective matter?

GreenSugar
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Location: California

Vignetting question

Post by GreenSugar »

Hope one of you kind I have been working with a Nikkor 200 mm as the tube lens between Mitutoyo 10X and Nikon D810. I recently purchased a Raynox 150 and tried it with Nikon F mount extension tubes instead of the M42 threaded style and am getting heavy vignetting when shooting full frame. One image from the stack is attached for reference. Will the vignetting persist in full frame with the M42 threaded tubes? Thanks!Image
PaulF209

rjlittlefield
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Post by rjlittlefield »

GreenSugar, take a look and read the discussion at http://www.photomacrography.net/forum/v ... hp?t=35350 . The most common place where vignetting occurs, especially with Nikon, is at the back end of the tubes where they enter the camera body. The Nikon bayonet by itself is just barely wide enough for light to reach the corners of a fullframe sensor, when it starts from a point roughly 200 mm in front of that. So, you want the thinnest possible walls = widest clear diameter you can get at at the camera body. The best approach is what's shown in that link: tubes at the body that are built to go directly from a wide tube down to a Nikon bayonet.

Also relevant here is the question that paleblue asked just above yours (but 3 years earlier, and never answered, oops!).

First, answering paleblue's question...
paleblue wrote:If the objective you're using is infinity corrected, then isn't all the light hitting the lens tube parallel? How can the distance between the lens tube and objective matter?
With an infinity objective, all of the light rays from a single point on the focused subject leave the objective parallel to each other, as if that point were at infinity. But the light rays from one point on the subject are not parallel to those from a different point on the subject. (If they were, there'd be no way to tell which were which, since every bundle of rays fills the entire rear aperture of the objective.)

The light rays from points away from the center of the field leave the objective at an angle, getting farther from the center with increasing separation. This makes them hit the tube lens at various distances from center. Changing the separation between objective and tube lens changes the distance away from center, for light rays at the same angle.

If the distance away from center is small, then changing it only makes small changes in image quality, by affecting aberrations.

But if the distance away from center becomes too large, all or part of the bundle may get blocked from reaching the sensor, either by failing to enter the tube lens at all, or by entering the tube lens at a distance away from center that causes it to be blocked closer to the sensor. Either of those cases causes vignetting.

So, having the widest possible clear diameter at the camera also gives the most freedom to increase the separation between objective and tube lens. Usually this does not matter, but it could in unusual cases, say if you wanted extra space to insert a beam splitter for through-the-lens illumination.

--Rik

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