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07-24-2013, 05:13 PM - 1 Like   #16
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As long as you're blowing the budget, this is what I use: (not this exact one, but similar)



07-24-2013, 07:24 PM   #17
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QuoteOriginally posted by Kozlok Quote
As long as you're blowing the budget, this is what I use: (not this exact one, but similar)
lol I wish. That would be pretty sweet. Probably a large learning curve to operate. I think I need to master capturing images with photons before I move onto electron bombardment.

But don't think I haven't looked over used SEM parts on ebay in the past. Just for S&Gs.
07-25-2013, 12:45 PM - 1 Like   #18
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If you're just a hobbyist you can get a smaller SEM...
Phenom World - Scanning electron microscope, dektop SEM, tabletop SEM
07-25-2013, 02:50 PM   #19
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QuoteOriginally posted by TER-OR Quote
If you're just a hobbyist you can get a smaller SEM...
Phenom World - Scanning electron microscope, dektop SEM, tabletop SEM
Wow! That is pretty darn cool. I wonder what they cost? I didn't want to bug them by requesting a quote. If you do not know off of the top of your head then it is no big deal since I'd still imagine it being out of my price range. Most likely it would cost more than the 645D which is out of my price range.

Speaking of blowing my budget, I bit the bullet and just bought a 40 and a 25mm luminar that were packaged together at a reasonable cost. It came packaged with a 50mm enlarger lens as well though I do not know any information on it since none was really stated. It didn't really matter since I was after those two luminars. The entire package came out an estimated 200-300 bucks less than had I bought them both separate so hopefully I can have some fun with those. They should get me in the magnification ranges I was looking for. The original package deal had the 63mm luminar in it as well which would have been nice and would have been a good deal at 1200 bucks I'd imagine. I do not know how much the prices of those lenses fluctuates though so who knows, for the 800 bucks I paid I may have gotten taken. I still plan on playing with some enlarger lenses though in the near future.

And if a home desktop SEM ever falls into my price range...

Lucky you Kozlok on getting to use one for work. Sounds like you have a fun a job.

Thanks all for your help.

07-25-2013, 07:00 PM   #20
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When I owned my own darkroom, I made my own mount for my Super Program with a K-mount body cap, some epoxy, an enlarging lens mount, and my bellows unit. It was fun until the novelty wore off.

It's been 30+ years since I did this, and I gave away my mount long ago. What I remember is most enlarging lenses are far more subject to flare than almost any 'ordinary' camera lens. It makes sense. The only light in a darkroom is coming from behind the lens in a highly controlled manner. Putting an anti-glare coating on an enlarging lens is as useful as mammary glands on a chicken.
07-25-2013, 10:20 PM   #21
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QuoteOriginally posted by JimJohnson Quote
When I owned my own darkroom, I made my own mount for my Super Program with a K-mount body cap, some epoxy, an enlarging lens mount, and my bellows unit. It was fun until the novelty wore off.

It's been 30+ years since I did this, and I gave away my mount long ago. What I remember is most enlarging lenses are far more subject to flare than almost any 'ordinary' camera lens. It makes sense. The only light in a darkroom is coming from behind the lens in a highly controlled manner. Putting an anti-glare coating on an enlarging lens is as useful as mammary glands on a chicken.
I often used a Nikkor 105mm enlarger lens on my Pentax 6X7. With a normal rubber hood, flare was not usually a problem - I fabbed an adapter for 49mm accessories.
07-26-2013, 04:08 AM - 1 Like   #22
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QuoteOriginally posted by Phosphene Quote
I was looking for some suggestions on what you may use if you were to try and go anywhere from 5X-30X magnification
5x is pretty much the point at which diffraction becomes a serious issue. A short FL lens may allow higher magnification than that, but if you are at f/5.6 or a higher f-number the extra magnification won't reveal more detail -- diffraction kills it. The quest is to find a lens that is sharp below f/5.6. Hence microscope objectives, some of which have an effective aperture of around f/2.

Another thing to keep in mind, in my experience used enlarger lenses bought on eBay are quite likely to be infested with fungus.
07-26-2013, 01:00 PM   #23
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This site was linked in another thread. There are tests of various lenses used on bellows including enlarging lenses, microscope objectives, etc. List are the various magnifications at respective extension lengths.

Macro lens tests


Last edited by Not a Number; 07-26-2013 at 01:06 PM.
07-28-2013, 02:01 PM   #24
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QuoteOriginally posted by Phosphene Quote
Wow! That is pretty darn cool. I wonder what they cost? I didn't want to bug them by requesting a quote. If you do not know off of the top of your head then it is no big deal since I'd still imagine it being out of my price range. Most likely it would cost more than the 645D which is out of my price range.
.
Yeah, they originally retailed for $85K - though I'm sure used will be a bit less expensive. I'm also not sure whether it handles sample prep, which is an art of its own...and equipment of its own.
07-30-2013, 04:23 PM   #25
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I don't know if I have missed it but no one seems to have answered the OPs questions, what lenses, what working distances and what magnifications


Here is the answer short and sweet.

Regardless of focal length 1:1 is reached at 2x focal length working distance, and infinite magnification is reached at a working distance of the focal length

Magnification is a function of the ratio of working distance to lens/focal plane distance, but note infinite magnification also requires infinite distance to the focal plane
07-30-2013, 07:26 PM   #26
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The website I linked above gives working distances along with magnification and extension with various enlarger lenses.
09-19-2013, 08:02 AM   #27
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I bought a Spiratone bellows(enlarging) lens on ebay for $30. It is a 75mm f3.5 T mount lens (It says flat field macro lens on the box). On the front the threads for a filter are 55mm but the pitch is different than normal. However since the threads are plastic you can force on a step up ring and it is pretty secure. So I forced on a 55-58mm step up ring and leave it on permanently. To the step up ring I installed a 58mm male to male reversing ring. I have tried mounting it on the front of the following lenses all of which take 58mm filters. The adaptall 135mm f2.5, the adaptall 200mm f3.5 and the adaptall 300mm f5.6. With the 135mm you get 1.8X, with the 200mm you get 2.66X and with the 300mm you get 4X. The working distance is about two inches on the 300mm and a little more on the other two lenses. At 1X a US penny just about fills the frame. At 1.8X and 2.66X if you focus on the date you see the date clearly plus part of Lincoln's face. At 4x you only have the date in the frame. One advantage of stacking the lenses vs using a bellows or extension is that the lens on the camera retains all of it's functions. I use a PK A adapter with the above adaptall lenses. Obviously you need a focusing rail but it only needs to be a 2 way.
09-24-2013, 03:24 PM   #28
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Sorry, should have given some distances. I reverse various enlarger lenses but the working distance is usually around 5-10cm, more towards the 5 end (up to about 5:1). I have a scruffy piece of paper with measurements somewhere but I lost it . JML20x objective for 20x, wd touch under 1 cm.
09-25-2013, 01:17 AM   #29
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I reverse-mount wide-angle lenses for extreme macros.Here's a YouTube video I did showing my results. I liked the Nikon Series E 36-72mm best in terms of quality-magnification-and usability taken as a package. I imagine that with a second bellows or some macro tubes, the Series E could make some ridiculously good super macros.

09-25-2013, 01:48 PM - 1 Like   #30
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Your video on reversing lenses for macro was interesting. The problem with simply reversing a lens is that you lose the connection between the camera and the lens so you can no longer control the lens from the camera. Another way to do it is to mount one lens on the camera in the normal way and then to reverse a second lens in front of the first lens. To do so you use a male to male reversing ring. So what you are doing is using the second lens in the same way as a close up lens except you have the potential to get much higher magnification. With this setup you divide the focal length of the reversed lens in front into the focal length of the lens mounted on the camera to get the magnification. So if you have a 200mm lens mounted on the camera in it's normal position and a 100mm lens reversed in front then you would get 2X magnification. With the same 200mm mounted on the camera and a 50mm lens reversed in front you would get 4X magnification, etc. You can use whatever combination of focal lengths you wish to give you the desired magnification but longer lenses give you more working distance. Some people like to use an enlarging or bellows lens for the reversed lens in front because since they lack a focusing mechanism (which you don't need anyways) they are shorter and lighter weight. You set the f stop of the reversed lens in front wide open and use the camera to set the lens mounted to the camera to wherever f stop you wish. At such high magnifications you would probably want to use a focusing rail. Some people refer to using two lenses together in this way as "stacking". Normally you would use stacking to get between 2X and 6X magnification. A normal macro lens gives you 1X and if you put an achromatic closeup lens in front of it ( like a +5) you might get 1.5X so with stacking you can get much higher. A good achromatic closeup is expensive (such as the Canon 500d or 250d) but a reversed camera lens on front is also of good quality but might not cost you anything if you have one laying around. The best book I have ever read on this subject is John Shaw's "Closeups in Nature". It was written back in the film days but no more recent book that I know about is as complete or as good. One thing John Shaw recommends is that if you buy an inexpensive enlarging lens just to use for stacking then to fashion some kind of hood and permanently attach it to the back of the lens to protect the glass. If you are focusing real close you don't want to bump the glass into the subject. You can buy a used copy of John Shaw's book on amazon.com for just a couple of dollars and is very worthwhile if you have any interest whatsoever in macrophotography.

Last edited by bruceinvolcan; 09-25-2013 at 02:14 PM. Reason: Correct spelling
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