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11-07-2009, 04:00 AM   #16
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QuoteOriginally posted by wallyb Quote
Am I crazy or wouldn't it just be best to get an extension tube? No interfering optics?
You are not crazy. An extension tube is the optically best and certainly least expensive route to high quality macros. (Less than $10USD delivered on ebay these days!)

But carrying and clipping on an achromatic close-up lens is more convenient when you are on a walk-about.

Dave in Iowa

11-07-2009, 06:07 AM   #17
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QuoteOriginally posted by wallyb Quote
Am I crazy or wouldn't it just be best to get an extension tube? No interfering optics?
An extension tube can be a good way to do close-ups if the lens mounted on the tube is corrected for short distances. A 50/1.4 normal lens (like the Pentax FA 50/1.4) mounted on extension tubes does not provide good results, because the fast "normal" lenses are optimized for shooting at infinity or at distances of several meters from the subject and lead to mediocre results when used for macro. A 5 element Heliar, a 4 element Tessar or even a triplet will yield much better results at 1:1 when mounted on extension tubes (many macro lenses are in fact Heliar or Tessar designs). In short, an extension tube doesn't allow the photographer to dispense with a macro lens.

Also don't forget that extension tubes cause an important light loss when used for high magnification ratios.

So, no, an extension tube is not a always perfect solution for macro.

Cheers!

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11-07-2009, 09:22 AM   #18
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QuoteOriginally posted by newarts Quote
But carrying and clipping on an achromatic close-up lens is more convenient when you are on a walk-about.
Exactly. The photo I posted above was from World Photo Day. I was shooting my FA77 but carried a polariser and a close-up adapter to give me more scope. Turned out my best shots were macros.
11-07-2009, 11:32 AM   #19
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QuoteOriginally posted by Abbazz Quote
Also don't forget that extension tubes cause an important light loss when used for high magnification ratios.
This is also true with macro lenses. At 1:1 magnification, a macro lens can "lose" two stops compared to when focusing at infinity (e.g. effective aperture is F/8 when the aperture ring is at F/4).

11-07-2009, 04:44 PM   #20
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QuoteOriginally posted by wallyb Quote
Has everyone forgotten what an extension tube does?
No, I remember - that's the thing where you have to remove your lens from the camera in order to mount and unmount the tube, making it rather more a pain to use than an achromatic closeup lens, without really improving the results much. It's also the thing that can be hard to find if you need it to have electrical contacts to be able to control the aperture for lenses with no aperture ring like the DA40. But sure, if you have one available and don't mind the extra hassle, they produce great results too.
11-07-2009, 04:56 PM   #21
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QuoteOriginally posted by Marc Sabatella Quote
No, I remember - that's the thing where you have to remove your lens from the camera in order to mount and unmount the tube, making it rather more a pain to use than an achromatic closeup lens, without really improving the results much. It's also the thing that can be hard to find if you need it to have electrical contacts to be able to control the aperture for lenses with no aperture ring like the DA40. But sure, if you have one available and don't mind the extra hassle, they produce great results too.
And a macro filter is also the thing that degrades the optical quality of the lens, curves the field of focus, and also does not offer electrical contacts , since the closer you get to your subject (with the filter on), the less light comes in as well.

They each have their uses, and I think an extension tube would be suited well to what K206 wants to do, considering he's new to the field of macro photography.
11-07-2009, 06:28 PM   #22
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QuoteOriginally posted by flippedgazelle Quote
Have you actually compared them? From what I've read online, the 500D dpoesn't appear to be any better than the Raynox. But I haven't seen any samples.
Yes, I tried them both. I bought the combo Raynox system from B&H about 3 years ago, and replaced it with the Canon 500D when I switched camera systems.

The Raynox never sat square and sometimes shifted on my lens at the time (Nikon 70-300).

Sorry, I suspect the glass was not up to the same quality as the Canon. I thought the colours were poor compared to Canon samples I saw. Maybe you get what you pay for. The Raynox felt like more of a gimmick than a piece of optical glass. I've seen some terrific photos from Raynox users, but many were cropped to avoid vignetting. Maybe it depends on the lens and element size combo. The screw-on Canon 500D is simple and small acting like a perfectly fitting magnifying lens. If you are MF and peering though the VF, this works far better for me.

That is one nice shot of the bug on the blue flower.
11-07-2009, 09:08 PM   #23
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QuoteOriginally posted by Aristophanes Quote
That is one nice shot of the bug on the blue flower.
Thanks! I was lucky to get it, hand-held with a breeze blowing.

11-07-2009, 09:19 PM   #24
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QuoteOriginally posted by Aristophanes Quote
Yes, I tried them both. I bought the combo Raynox system from B&H about 3 years ago, and replaced it with the Canon 500D when I switched camera systems.

The Raynox never sat square and sometimes shifted on my lens at the time (Nikon 70-300).

Sorry, I suspect the glass was not up to the same quality as the Canon. I thought the colours were poor compared to Canon samples I saw. Maybe you get what you pay for. The Raynox felt like more of a gimmick than a piece of optical glass. I've seen some terrific photos from Raynox users, but many were cropped to avoid vignetting. Maybe it depends on the lens and element size combo. The screw-on Canon 500D is simple and small acting like a perfectly fitting magnifying lens. If you are MF and peering though the VF, this works far better for me.

That is one nice shot of the bug on the blue flower.
Thank you for the detailed answer. I might just have to pick up the 500D to compare with my Raynox, although I'm pretty happy with the Raynox's quality and haven't had any issues with vignetting. But hey, always nice to try something new and maybe better.
11-08-2009, 01:48 AM   #25
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I just tried to take the same picture with my FA*77, first by using a Raynox 250 and then by using Pentax Auto Bellows.

The Raynox DCR-250 has a power of 8 diopters. It means that, with the lens set at infinity, it will focus at 1m / 8 = 0.125m which, for a 77mm lens means a 0.6x magnification ratio (77/125).

With the Raynox on the FA*77, the exposure was F/8 1/800 sec. With the bellows, set for the exact same magnification, the exposure was F/8 1/250 sec., almost 2 stops slower for a magnification still smaller than life size!

That's why I prefer taking the Raynox in my photo bag when I'm on the move, rather than the bulky bellows. With the Raynox, I can get surprisingly good pictures at 2.56x magnification with my FA 80-320 consumer zoom used at the 320mm setting, handheld and without any additional equipment.

It is of course possible to get better pictures -- and at a much higher magnification ratio -- with the bellows, or with extension tubes for that matter, but it requires a lot of care and dedication. First, getting top quality pictures requires a lens corrected for macro shooting or an ordinary lens used in inverted position. It also requires a flash, because the lens + bellows combo is simply too slow to be usable in natural light at high magnification ratios, except maybe under the brightest sun. Then it will also require a tripod, because the whole kit is simply too bulky to handhold.

To get back to the question of the original poster, the Hoya +10 is a 2 element achromat with a power of 10 diopters, so it will have a magnification ratio of 1:2.5 with the DA 40 at infinity, or 1:1.72 with the Helios-44, also at infinity. The Raynox DCR-250 is a 3 element achromat with a power of 8 diopters, so it will have a magnification ratio of 1:3.125 with the DA 40, or 1:2.15 with the Helios-44. The Raynox DCR-150 is also a 3 element achromat but with a power of 4 diopters, so it will have a magnification ratio of 1:6.25 with the DA 40, or 1:4.31 with the Helios-44. If you want to wander into the 1:1 or larger magnification ratios with these diopters, you have to get a longer lens (at least 135mm).

Here's a nice web page about diopters ans close-up lenses, with all the formulas: Fuzzcraft.com | A list of achromatic close-up lenses | Photography, audio and light DIY projects

Cheers!

Abbazz
11-08-2009, 02:38 AM   #26
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QuoteOriginally posted by Aristophanes Quote
Yes, I tried them both. I bought the combo Raynox system from B&H about 3 years ago, and replaced it with the Canon 500D when I switched camera systems.

The Raynox never sat square and sometimes shifted on my lens at the time (Nikon 70-300).

Sorry, I suspect the glass was not up to the same quality as the Canon. I thought the colours were poor compared to Canon samples I saw. Maybe you get what you pay for. The Raynox felt like more of a gimmick than a piece of optical glass. I've seen some terrific photos from Raynox users, but many were cropped to avoid vignetting. Maybe it depends on the lens and element size combo. The screw-on Canon 500D is simple and small acting like a perfectly fitting magnifying lens. If you are MF and peering though the VF, this works far better for me.

That is one nice shot of the bug on the blue flower.
Have you checked out the Raynox Macro Club on this forum?
11-08-2009, 06:50 AM   #27
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QuoteOriginally posted by Abbazz Quote
The Raynox DCR-250 has a power of 8 diopters. It means that, with the lens set at infinity, it will focus at 1m / 8 = 0.125m which, for a 77mm lens means a 0.6x magnification ratio (77/125).
Nice informative post!
11-08-2009, 10:01 PM   #28
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QuoteOriginally posted by rparmar Quote
Nice informative post!
x2!!

I was hoping someone would do the math on this thing AND provide a link to a resource!



Steve
11-08-2009, 10:20 PM   #29
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QuoteOriginally posted by wallyb Quote
And a macro filter is also the thing that degrades the optical quality of the lens, curves the field of focus, and also does not offer electrical contacts
You don't need electrical contacts on a filter, of course. And while some closeup lenses do worse than others, the Raynox and achromats do so well most people could probably not tell the difference between them and an extension tube. As for curving the focus field, that may be - I hadn't heard that, nor noticed it myself. Sure, they aren't perfect. But I suspect you are underestimating just how well these achromats do work.

Anyhow, obviously, you're right that an extension tube can work well too if you don't mind the fact that they are harder to find and harder to use. So if you happen to be one of the few people *not* happy with the results from a achromat, then it could be worth the effort.
11-08-2009, 10:25 PM   #30
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QuoteOriginally posted by Aristophanes Quote
The Raynox never sat square and sometimes shifted on my lens at the time (Nikon 70-300).
I am not a fan of the clip on adapter, I'd agree. And the Raynox *is* too small for larger lenses like a 70-300, so it will vignette. But used on a smaller lens, vignetting is not a problem, and using a simple stepping ring instead of the clip on adapter solves the shifting problem. I'd be curious to see actual head-to-head comparisons, but nothing I've seen suggests there would be any significant differences.
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