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And before I leave, a bit of metalworking (ON TOPIC!)
As it will likely be a year or two before I even start to acquire any
machinery again, and not knowing if potential employers down there are friendly to the concept of G-jobs, I had to choose which of the many projects on hold around here got done before closing up shop. I chose my macro slide for photography. I built a setup for my brother using a Nikon microscope, set up with stepper motor driving the fine knob. It will give him insanely fine movement, once he gets around to finishing the electronics to drive it. I'm not an electronics person... I looked at the StackShot macro rail, nice but too expensive, and if I was going to make something, I wanted something a bit more precise that bronze bushings on shafts. What I came up with, can legitimately be called gross overkill, but I kinda like gross overkill, especially when it looks nice, and works better. Got a couple photos before I take it apart for anodize: https://picasaweb.google.com/janders1957/MacroSlide?authuser=0&authkey=Gv1sRgCMPhwduWyMvQGg &feat=directlink Jon |
And before I leave, a bit of metalworking (ON TOPIC!)
And for those that don't know what this is all about, at very high
levels of magnification, depth of field becomes vanishingly small. If you've seen a photo of an insect head, all in focus, tiny hairs and all, that was likely done via a process called stacking. Dozens to hundreds of photos are taken, with the camera incremented a predetermined distance between each shot. Software does some sort of magic and builds a single photo combining what it determines are the in focus portions of each frame. Jon |
And before I leave, a bit of metalworking (ON TOPIC!)
On 3/3/2014 7:39 PM, janders wrote:
And for those that don't know what this is all about, at very high levels of magnification, depth of field becomes vanishingly small. If you've seen a photo of an insect head, all in focus, tiny hairs and all, that was likely done via a process called stacking. Dozens to hundreds of photos are taken, with the camera incremented a predetermined distance between each shot. Software does some sort of magic and builds a single photo combining what it determines are the in focus portions of each frame. Jon How clever. The stuff one learns on RCM. |
And before I leave, a bit of metalworking (ON TOPIC!)
On Mon, 03 Mar 2014 20:25:18 -0500, Bob Engelhardt
wrote: On 3/3/2014 7:39 PM, janders wrote: And for those that don't know what this is all about, at very high levels of magnification, depth of field becomes vanishingly small. If you've seen a photo of an insect head, all in focus, tiny hairs and all, that was likely done via a process called stacking. Dozens to hundreds of photos are taken, with the camera incremented a predetermined distance between each shot. Software does some sort of magic and builds a single photo combining what it determines are the in focus portions of each frame. Jon How clever. The stuff one learns on RCM. Actually, LONG beforer stacking was possible, high definition macro photography with decent depth of field was possible. It is not possible in low light conditions or with non-stationary subjects, A small apperature and a long exposure at a long focal length gives a large depth of feild. Shorten the focal length, open the aperature, and you lose depth of field. |
And before I leave, a bit of metalworking (ON TOPIC!)
|
And before I leave, a bit of metalworking (ON TOPIC!)
janders wrote:
As it will likely be a year or two before I even start to acquire any machinery again, and not knowing if potential employers down there are friendly to the concept of G-jobs, I had to choose which of the many projects on hold around here got done before closing up shop. I chose my macro slide for photography. I built a setup for my brother using a Nikon microscope, set up with stepper motor driving the fine knob. It will give him insanely fine movement, once he gets around to finishing the electronics to drive it. I'm not an electronics person... I looked at the StackShot macro rail, nice but too expensive, and if I was going to make something, I wanted something a bit more precise that bronze bushings on shafts. What I came up with, can legitimately be called gross overkill, but I kinda like gross overkill, especially when it looks nice, and works better. Got a couple photos before I take it apart for anodize: https://picasaweb.google.com/janders1957/MacroSlide?authuser=0&authkey=Gv1sRgCMPhwduWyMvQGg &feat=directlink Nice. I switched from interest to learning machining so I could make parts used with and for cameras. I use a Novoflex macro rail, but the backlash after tuning it still bothers me, even though it has no effect in the end. The precision, fit and finish of parts in older cameras is mind blowing to me, and provides some really high standards to work towards. |
And before I leave, a bit of metalworking (ON TOPIC!)
On 3/4/2014 8:27 AM, Cydrome Leader wrote:
The precision, fit and finish of parts in older cameras is mind blowing to me, and provides some really high standards to work towards. My brother now has my Dad's old Zeiss Ikon Contaflex. I don't quite recall how it operated, but basically within limits, if you changed aperture, it would adjust shutter speed, and likewise, change shutter speed, it would adjust aperture. All done mechanically. Boy, would I love to see how that was done internally. And to think stuff like this was all designed on paper, long before CAD... Jon |
And before I leave, a bit of metalworking (ON TOPIC!)
janders wrote:
On 3/4/2014 8:27 AM, Cydrome Leader wrote: The precision, fit and finish of parts in older cameras is mind blowing to me, and provides some really high standards to work towards. My brother now has my Dad's old Zeiss Ikon Contaflex. I don't quite recall how it operated, but basically within limits, if you changed aperture, it would adjust shutter speed, and likewise, change shutter speed, it would adjust aperture. All done mechanically. Boy, would I love to see how that was done internally. And to think stuff like this was all designed on paper, long before CAD... I've not seen that particular camera, but I know what you're talking about. You'd set an exposure value and it would always meet that, even if you changed aperture or shutter speed. Even in this group, the default answer for lots of simple stuff is "microcontroller", which is silly. The one fairly amazing place mechanical devices got simpler and not entirely though use of microcontrollers is inside VCRs. The sheer number of motors, cast and machined parts, and just stuff in old VCRs was staggering, nearly to the point of what's inside a camera, but all spaced out. The lastest units made were down to something like 3 motors, sheet metal and plastic, and it doesn't look like any of the parts we impossible to make back in the late 1970s or early 80s. |
And before I leave, a bit of metalworking (ON TOPIC!)
I contacted you about the air compressor and to find out how far away you
were, but never got a reply. I must have gone to your junk mail folder. Sadly now that you have posted were Green Valley is I think that the freight or fuel to come get it would kill it for me. Best of luck in Oz. --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com |
And before I leave, a bit of metalworking (ON TOPIC!)
On 3/4/2014 11:24 AM, Bob La Londe wrote:
I contacted you about the air compressor and to find out how far away you were, but never got a reply. I must have gone to your junk mail folder. Sadly now that you have posted were Green Valley is I think that the freight or fuel to come get it would kill it for me. Best of luck in Oz. Sorry Bob, my reply bounced, said mailbox over quota. I'm just running in 10 directions at once and forgot to follow up. Jon |
And before I leave, a bit of metalworking (ON TOPIC!)
"janders" wrote in message
... On 3/4/2014 11:24 AM, Bob La Londe wrote: I contacted you about the air compressor and to find out how far away you were, but never got a reply. I must have gone to your junk mail folder. Sadly now that you have posted were Green Valley is I think that the freight or fuel to come get it would kill it for me. Best of luck in Oz. Sorry Bob, my reply bounced, said mailbox over quota. I'm just running in 10 directions at once and forgot to follow up. Jon No worries. I have been shopping for a bigger compressor for a while now. My roll around is plumbed into the shop air. Its enough most of the time, but I would really like to have one a bit bigger. I just looked at an old Puma yesterday. Sadly, the bottom of the tank blew out while I was standing there pumping it up. Or happily I suppose. Better then than a few hours later when I powered it up in my shop I guess. --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com |
And before I leave, a bit of metalworking (ON TOPIC!)
On Tue, 4 Mar 2014 14:29:16 -0700, "Bob La Londe"
wrote: "janders" wrote in message ... On 3/4/2014 11:24 AM, Bob La Londe wrote: I contacted you about the air compressor and to find out how far away you were, but never got a reply. I must have gone to your junk mail folder. Sadly now that you have posted were Green Valley is I think that the freight or fuel to come get it would kill it for me. Best of luck in Oz. Sorry Bob, my reply bounced, said mailbox over quota. I'm just running in 10 directions at once and forgot to follow up. Jon No worries. I have been shopping for a bigger compressor for a while now. My roll around is plumbed into the shop air. Its enough most of the time, but I would really like to have one a bit bigger. I just looked at an old Puma yesterday. Sadly, the bottom of the tank blew out while I was standing there pumping it up. Or happily I suppose. Better then than a few hours later when I powered it up in my shop I guess. One can buy a decent pump/motor on a rotted tank..and mount it on a decent tank with a bad motor/pump We do it regularly and for very little money. After all...who is going to pay a lot for a compressor with a bad pump or tank? Just takes a couple hours to build it up. --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com -- " I was once told by a “gun safety” advocate back in the Nineties that he favored total civilian firearms confiscation. Only the military and police should have weapons he averred and what did I think about that? I began to give him a reasoned answer and he cut me off with an abrupt, “Give me the short answer.” I thought for a moment and said, “If you try to take our firearms we will kill you.”" --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com |
And before I leave, a bit of metalworking (ON TOPIC!)
"Gunner Asch" wrote in message
... On Tue, 4 Mar 2014 14:29:16 -0700, "Bob La Londe" wrote: "janders" wrote in message ... On 3/4/2014 11:24 AM, Bob La Londe wrote: I contacted you about the air compressor and to find out how far away you were, but never got a reply. I must have gone to your junk mail folder. Sadly now that you have posted were Green Valley is I think that the freight or fuel to come get it would kill it for me. Best of luck in Oz. Sorry Bob, my reply bounced, said mailbox over quota. I'm just running in 10 directions at once and forgot to follow up. Jon No worries. I have been shopping for a bigger compressor for a while now. My roll around is plumbed into the shop air. Its enough most of the time, but I would really like to have one a bit bigger. I just looked at an old Puma yesterday. Sadly, the bottom of the tank blew out while I was standing there pumping it up. Or happily I suppose. Better then than a few hours later when I powered it up in my shop I guess. One can buy a decent pump/motor on a rotted tank..and mount it on a decent tank with a bad motor/pump We do it regularly and for very little money. After all...who is going to pay a lot for a compressor with a bad pump or tank? Just takes a couple hours to build it up. I have been keeping my eye out for those options as well. (That Puma was a little smaller than I really want anyway, but the price was right.) --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com |
And before I leave, a bit of metalworking (ON TOPIC!)
On Monday, March 3, 2014 9:12:10 PM UTC-5, janders wrote:
On 3/3/2014 5:56 PM, clare....r.on.ca wrote: Actually, LONG beforer stacking was possible, high definition macro photography with decent depth of field was possible. Jon I remember some photo's that were made using a special set up for high magnification. The camera was an a slide along with a light source that illuminated a narrow slot. The camera was focused at the light. To photograph something the camera and light source would move. The photo was taken with an open shutter and the exposure determined by how fast the light and camera moved. Dan |
And before I leave, a bit of metalworking (ON TOPIC!)
On 2014-03-04, janders wrote:
On 3/4/2014 8:27 AM, Cydrome Leader wrote: The precision, fit and finish of parts in older cameras is mind blowing to me, and provides some really high standards to work towards. My brother now has my Dad's old Zeiss Ikon Contaflex. I don't quite recall how it operated, but basically within limits, if you changed aperture, it would adjust shutter speed, and likewise, change shutter speed, it would adjust aperture. All done mechanically. Boy, would I love to see how that was done internally. And to think stuff like this was all designed on paper, long before CAD... I had a and use a lot a Contaflex, back in about the 1962-1964 period. The Contaflex (and many other cameras of the period) used what is called an "EV" (Exposure Value) scale. You lock the shutter ring and the aperture ring together (and they move in steps of double/half light through aperture or time the shutter is open). As far as the film is concerned, any of those combinations is equal to all the others. However, depth of field and motion stoppage were tradeoffs at the ends of the range. The shutter speeds in later cameras were weird values which were closer to a step of two one over (1, 2, 4, 8* 15, 30, 60* 125, 250, 500, 1000) (the intervals with a '*' in them instead of a comma were where the scale slipped a little for better numbers). The older ones were more like (1, 2, 5, 10 25 50 100 250 500 1000) (favoring more human-friendly numbers over closer doubling). The aperture numbers look weirder, but since they represent the diameter (relative to the focal length), and the exposure is more a function of the area, they also are pretty good factor of two increases: (64, 32, 16, 8, 4, 2, 1) (with extra half-stop values in between so you see things like 2.8, 3.5, 4.5, 11 and so on). But make the shutter speed ring and the aperture ring lock together, and step in the proper direction (slower shutter speed for numerically larger (thus smaller area) apertures, and the EV system just works without any fancy mechanical coupling -- other than locking the two rings together. When you moved to fully interchangeable lens cameras, with focal plane shutters, it got more difficult to couple them together like that. The shutter was usually a curtain which traveled across the back (or up and down with some), and the aperture being on the lens which bayoneted (or screwed) into the body. the man thing then was a way to couple the aperture information into the body and couple it and the shutter speed dial to the meter. (The Contaflex only had interchangeable front elements, and the aperture and the shutter were both built into the stack from the body out to the front element, so the coupling was easy. Zeiss made more serious cameras as well -- the Contax (which was fully interchangeable, but not a SLR like the Contaflex) and later the Contarex Super (fully interchangeable lenses *and* focal plane shutter). I've got an old Contax, but I've never had my hands on a Contaflex Super. The Contax was the Zeiss equivalent of the Leica (both focal plane shutters and fully interchangeable lenses). The Japanese Cannon started as a clone of the Leica, and the Japanese Nikon started as a clone of the Zeiss Contax. Each camera line had leftovers from those days for quite a while. For example the top end Nikon F SLR had the ability to use the Contax Cassettes in place of the normal disposable (or somewhat reusable) 35mm cassettes. It fully opened so there was no scratching of the film through dust caught in the felt light trap as you locked the back in place. The Contax (and the Contaflex) could use two of them, so the film would roll from one to the other, and you could then change between films in mid roll at the cost of a couple of frames. The Nikon F, however, had a captive take-up spool, so you could only use the Contax Cassette as the source, and had to rewind. Still no film scratches from dust trapped in the light trap of a standard 35mm cassette -- and I had a lot of those. EV has pretty much gone away with today's cameras with built-in metering and in many cases, control of both shutter speed and aperture without even letting the photographer control anything (in the cheaper point-and-shoot cameras). :-) Enjoy, DoN. -- Remove oil spill source from e-mail Email: | (KV4PH) Voice (all times): (703) 938-4564 (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html --- Black Holes are where God is dividing by zero --- |
And before I leave, a bit of metalworking (ON TOPIC!)
On 5 Mar 2014 05:26:48 GMT, "DoN. Nichols"
wrote: EV has pretty much gone away with today's cameras with built-in metering and in many cases, control of both shutter speed and aperture without even letting the photographer control anything (in the cheaper point-and-shoot cameras). :-) The Canon A1 was one of the first with full "program" exposure/speed controls. They were/ARE very good cameras and its taken 30 yrs for the digitals to catch up to their abilities. I shoot digitals MOST of the time..but regularly burn film in the A1s (along with some of the other 50 or so film cameras I own) -- " I was once told by a “gun safety” advocate back in the Nineties that he favored total civilian firearms confiscation. Only the military and police should have weapons he averred and what did I think about that? I began to give him a reasoned answer and he cut me off with an abrupt, “Give me the short answer.” I thought for a moment and said, “If you try to take our firearms we will kill you.”" --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com |
And before I leave, a bit of metalworking (ON TOPIC!)
On 3/4/2014 1:29 PM, Bob La Londe wrote:
Sadly, the bottom of the tank blew out while I was standing there pumping it up. Or happily I suppose. Better then than a few hours later when I powered it up in my shop I guess. Yowza... glad nobody was hurt! Jon |
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