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04-09-2019, 05:37 AM - 1 Like   #31
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there are a bunch of possible ways to go for macro already listed with each and every ones personal favourite, so maybe the OP needs a summary.

basically there are 2 equipment approaches for macro / close up photography.

- Add a close up lens to the front of the camera, what this does is change (reduce) the focal length of the combined lens and as the distance to the sensor plane has not changed you can now focus closer at the loss of infinity focus
- Add an extension behind the lens such that it reduces the focusing distance,

both methods rely on the basic principle that magnification ultimately is the ratio between the subject to lens and sensor to lens distance.

adding to the front of the lens includes using close up lenses, marked in diopters, or by taking an existing lens and reversing it and attaching it to the front of another lens,

increasing the space on the back side of a lens is achieved either by adding a bellows, or extension tubes, a focusing helix, or is exactly what older style macro lenses actually did, provide a huge focusing helix and allow the lens to extend far away from the camera reducing allowing for both high magnification and close working distances.

there are pros and cons for both approaches the problem with close up lenses, is that as they effectively reduce the focal length of you lens, to achieve 1:1 magnification you may find your working distance is very short, but since they reduce the overall focal length, and the lens diameter has not changed, you actually gain in F stops, and as a result you have more light, and a bright viewfinder

lens extensions, effectively allow the light gathered by the lens to be spread out further, and as a result, you lose F stops, and the image gets dimmer, but you have greater subject working distance.

remember that for 1:1 the subject to lens and lens to camera distances are equal and exactly 2x the focal length, so lets consider a practical example, you have a 50mm lens, for 1:1 you need 50 mm of extension tubes and you have 100 mm distance from the lens element to the subject (roughly) for close up lenses to work up to 1:1 you would need to add to a 50mm lens you would need to add 11 diopters (most close up lens kits are a 1,2,4 diopter set so you would stack all 3 but that wont get you 1:1 reproduction with a 50mm but you will get a bright viewfinder.

it is a trade off, this is why for real micro work people use a short (i.e. wide angle lens) reversed

04-09-2019, 05:46 AM   #32
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Also remember this: A close up lens reduces the focus distance (=front of lens to subject) by a specific amount regardless of the focal length of the lens. So a Raynox 150 will provide a much higher magnification when attached to a long FL lens, or a zoom lens out at it's long end, than it will on a normal focal-length lens. On the other hand, the effect of an extension tube is just the opposite. With a short focal length lens a tube will give high magnification, but on a long FL lens the magnification with the same extension tube will be much less. IF you are attempting macro with a zoom lens, this means that a close-up filter is far more convenient because when you zoom, the subject will stay close to in focus, but with an extension tube behind a zoom lens, if you change focal length the subject will go wildly out of focus and will almost certainly require moving your camera back to re-achieve focus.

Last edited by WPRESTO; 04-27-2019 at 04:09 PM.
04-09-2019, 06:05 AM   #33
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Three images below:
1) Old (1980's) Tamron 28-105mm with Raynox 250, @ 105mm, focus to infinity
2) Tamron @ 105mm & Raynox, lens to closest focus
3) Pentax 200mm f4 SMCA lens with Raynox 150, focus @ infinity.

All shot @ f8 (I used this as standard during the testing in the belief it would give the best possible results from each lens. No sharpening applied PP, but some exposure adjustment

BTW: The Raynox do not work equally well on all lenses nor at all zoom settings. For example, when used on a Pentax 70mm f2.4, there was severe vignetting. I also tested an old (1980's) Tamron 70~300 zoom. The Raynox worked well @ 70mm, but was totally unacceptable @ 300mm.
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04-09-2019, 10:45 PM   #34
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Another thing you can do: in the 'macro by any means necessary' club you can see how other people are doing macro with macro lenses. You'll find results of most of the methods mentioned above there.

04-27-2019, 03:00 PM   #35
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Thanks a lot, everyone for their valuable suggestions.Sorry for the late reply - I got a bit lost with other things.

So I decided to buy the Raynox - 250. I am quite happy with the image quality. But the working distance is a big challenge. I am using it on my nifty fifty. The working distance is so close that it is impossible to use it in the field for live insects. Also due to the working distance, the composition is also a bit challenging. If the flowers are slightly bigger (or smaller for that matter) I can't get it in focus. This is quite limiting in what kind of things I can photograph. Am I missing something? I am assuming tubes in this regards can be helpful as one can use a different combination of tubes.

Few photos with my raynox
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04-27-2019, 04:12 PM   #36
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FYI: The Raynox 150 will double your working distance.(about 8 inches instead of about four inches) although obviously with less magnification if used on a lens of the same focal length
04-28-2019, 11:19 AM - 1 Like   #37
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QuoteOriginally posted by AlwaysAl Quote
Perhaps you might check out a bellows attachment instead of the extension tubes. From time-to-time- these things show up in the used equipment sections real cheap and they allow you to use your existing lens collection (as long as they have aperture ring unfortunately). As a word of caution, mine worked on every camera up to and including the K-5sii but the prism housing on the K-1 interferes and doesn't allow the connection. Additionally, these are great for table top macro stuff but not so convenient to travel. .
I found with bellows that a #1 extension tube of the back allows them to clear the prism extension. I use bellows quite extensively. Somewhere around I also have a helical extension tube which is a really nice piece of field equipment.
04-29-2019, 01:26 PM   #38
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Check out this guy's YouTube channel:

https://www.youtube.com/user/terser

Thomas Shahan

He's got a lot of neat tricks and suggestions, DIY approach to flash diffusers which is like the key to the kind of macro work he does and from what you have written, it's the direction your interest has taken you, too. You're not going to spend a lot of money, and still get the high quality results everyone wants.



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