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Old August 5th, 2005, 02:35 PM   #106
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Correction

The syringe part is the 1cc that use for insulin, not .5cc like I said before, sorry.

Quyen
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Old August 5th, 2005, 03:38 PM   #107
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Video Test..

OK I tried it today and not to bad... For some reason my GG which is 1500 grit by tholabs looks a bit mudier then I would want.. anyway look in the corner "sky" for the grain

http://s62.yousendit.com/d.php?id=2G...K8A66CNIPMMFC4

latter
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Old August 5th, 2005, 03:58 PM   #108
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Hey Quyen,

Did you try keeping the rubber bits on the bottom of the syringe - the plunger for lack of a better word? They might stop the vibration even more from making its way down the unit.
Just a thought.
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Old August 5th, 2005, 04:36 PM   #109
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Leo,

I put the syringe part in same as the one in picture. The big part stay out of the hole.
http://www.nuocsong.com/nhatho/adapter/syringe.JPG

Craig

I didn't think that anyone can build one that fast, congratulation. Saw your video and it's not really circular motion and the circle is tight. You may check the rubber feet to see if it's too tight. How long are the white parts? When shooting outside I suggest you use AES and use shutter speed 125 or less. Good job, keep it up man.

Quyen
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Old August 5th, 2005, 05:08 PM   #110
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Ok, my design

Ok, my design is a lot diferent then yours. I was already in a build and already had all the parts for your design. I take allergy shots,and had an old pager. I am also shooting with a medium format lens and a magnifier on the lens side of the GG to enlarge the hot spot, BUT keeping the grain as small as I can. This means I shoot straight off the GG, 2 inch GG... Also the hotspot is much larger on the GG becasue the lens is 3 inches from the GG... That's the reason the the magnifier works.

camera gg magnifer medium format lens

Anyway as for your question, The pegs or syringe plungers are only 1 inch long. I can actually make these as long at they come orginally so that's my next step. The longer the plunger the more the movement they have....I'll have to work on that next week due to working on my house on the week ends... That's my thoughts,,,
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Old August 5th, 2005, 09:17 PM   #111
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Quyen,

Just wondering how many lenses you have, and are finding a 50mm limiting? WIll youradapter work for a nikon mount?

How much would you suggest i spend on a montore for framing, and lenses.

Also what cam r u shooting on?

B. Sundry
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Old August 6th, 2005, 01:43 AM   #112
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B. Sundry

I have several FD lenses. The reason I use 50mm 1.4 is to demonstrate shallow DOF. This adapter can virtually use any lens.

How much you would spend will depend on your budget and your applications. I cannot answer this question for you. I saw some post with 5" and 7" LCD monitor, that's would be great if you can buy 1.

Below is a video file that has split between aerial image and image on GG. The shot was taken indoor using fluorescent light.

http://www.nuocsong.com/nhatho/adapter/split.mpg

Thanks.

Last edited by Quyen Le; August 6th, 2005 at 07:58 AM.
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Old August 6th, 2005, 02:45 PM   #113
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Quyen,

What do you do if you switch to a different type of lens? Different lenses have different focal length - do you adjust the syringes as required? Or do you make a few different setup of the device to accomodate?
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Old August 6th, 2005, 03:21 PM   #114
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Leo,

Just like a camera, when you attach another lens, it doesn't need to adjust anything. This thing has a camera like distance between the mount and GG. No adjustment needed, just plug and play, hope this helps, thanks.

Quyen
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Old August 6th, 2005, 03:37 PM   #115
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Ok, I am not really familiar with all optics, but I have three different lenses with different bayonette sizes and all different focal lenghts - so maybe we are talking about different things?
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Old August 6th, 2005, 03:55 PM   #116
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The focal length is the length from the focus plane (GG) to the end of the lens. It changes, but the distance between the mount and the GG does not.
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Old August 6th, 2005, 04:23 PM   #117
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Leo,

After doing reseach, I found that FD lenses are the cheapest yet have quality among Brand name lenses. the 50mm 1.4 will cost under $50 include shipping on ebay. If you plan to build/buy this unit, I think you better off settle for 1 lens mount. FD is the best in my opinion. Nikon is good but price is a little higher. EF lenses are good but has very limited control on apature when using manually. I can do different mounts but 1 unit will have only 1 mount to go with it either Nikon or FD. Hope this help, thanks.

Quyen
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Old August 6th, 2005, 07:33 PM   #118
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I think what Quyen means is that when you mount a different lens *of the same mounting style*, nothing changes.

If you were to mount a different lens of a different mounting flange style, by revising your adapter, then you'd need to move the GG or focusing screen.

This is because, the "focal length" - a better term is "registration depth" or "registration distance" - is measured from the lens mounting flange to the film plane. In our case, the film plane is replaced by ground glass or focusing screen, etc.

For an FD (and FL, etc) bayonet mount lens this distance is 42.0 mm.

For a Pentax (and compatible) M42 screw mount it's 45.46 mm.

For the Nikon bayonet it's 46.50 mm.

There are many other mounts, each with their own registration distance. You can find them on the web.

Here, for example: http://www.a1.nl/phomepag/markerink/mounts.htm

A final note - setting your registration distance absolutely correct is very important. If it's off a bit, you lose your infinity focus - aka long distance detail. The best way I've found to do this is to focus on a very distant point of light, at night. Then look at the GG/focusing screen with a magnifying glass or other visual aid. Even a half a millimeter of registration distance change makes a difference.
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Old August 6th, 2005, 10:44 PM   #119
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I wonder if there is a standard known distance measurement for optical screw threads, i.e. 10 rotations = 2 mm, or whatever it may be. Then one could mount the GG in the thorlabs adapter just by turning the retaining rings the right number of times and setting the GG in place.

Anyone know of this?
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Old August 7th, 2005, 12:51 AM   #120
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Yes, for screw mount lenses it's the count, in threads per inch or threads per millimeter (depending on how your lens mount is rated).

However, never rely on this! There are so many variables in terms of where and how you mounted your ground glass that it's pointless. Just move the GG in and out until you get infinity focus, then lock the GG it at that point.

If you are off a little bit it's impossible to tell at anything but infinity focus. You are basically creating a macro system, like having an tiny macro extension tube.

I have spent a lot of time looking at GG in or out of proper registration focus setting, and lots of the people on this forum have their adapters off a little bit (!). Again, it's impossible to tell based on looking at anything other than faraway shots, but, a lot of people could use a little bit of GG dialling in.
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