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03-25-2012, 08:24 PM   #16
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Paleo Pete: I've been meaning to check out the Tiny Flowers thread - maybe I'll do it right now. Yep, there are definitely some useful examples to learn from around here.

Concerning getting really close, you can find a few recent compacts that advertise 1cm focus distance. The claims don't always match reality, but a few do. My personal holy grail is the Ricoh GR Digital (III or IV). No joke - these little guys are capable of focusing on something that is TOUCHING the front of the lens.

03-26-2012, 12:24 AM   #17
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You can get that close with reversed lens stacking, and with extension on certain zooms, but I fail to understand why you would want to. Unless what you're shooting is both flat and translucent (like a film slide), you won't have sufficient DoF to do much (we're talking fractions of a millimeter of depth being in focus, potentially), and you won't likely be able to get enough light on the subject unless it is strongly backlit - the lens, and perhaps your body will be in the way.

Usually, the goal is to get as much magnification as you want, and still have enough working distance from the subject to make the shot work. This is why long macro lenses like the 150mm and the newly announced 180mm are so coveted. The longer focal length allows you to stay farther away, and still maintain the 1:1 magnification ratio. ~100mm is a very popular focal length for macro lenses because the working distance is still comfortable, but the cost isn't outrageous.

The other way to go is with an achromatic +dioptre addon lens. Raynox makes fine ones, in +4.5 and +8 dioptre strengths, and Opteka makes a +10 that is much cheaper but still quite good. The +10 has a fixed working distance of just shy of 4 inches. Your effective magnification is determined by the host lens, longer focal lengths providing higher magnification. Used with a shorter (perhaps 50ish mm) lens, the magnification wouldn't be so great, but you would still be quite close to your subject, and have a greater field of view, which seems to be what you want.

I just don't grasp why you want that, as opposed to higher magnification from the same distance or, preferably, farther away.
03-26-2012, 01:57 AM   #18
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Once you start unpacking the depth of field concept then start exploring the technique of focus stacking and related software.

I used to have a Canon Powershot A70 (IIRC) that I reverse mounted a Takumar 50mm 1.4 on and that gave me the magnification and the DOF that I was looking for but not the image size in megabytes that a bigger sensor gives...

It is just fun exploring all this stuff- camera geeks allof us
03-26-2012, 01:18 PM   #19
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Philoslothical - You got into a couple of points I meant to and forgot. Why would you want to is a very good point. I have to use a reflector with my flash to use it at all with the binocular lens rig, the flash shoots over the subject, not onto it. I like the binoclar lens setup really well, but I wish I could get further away, I have a lot of trouble getting that close (4 to 6 inches) to grasshoppers, spiders, damselflies, lizards, flies, bees...they don't like to let me close enough to use the 135mm and extension tubes, which gets me about a foot away.

Maybe for inanimate or non-mobile subjects like small flowers, an inch away would be acceptable, but as you also mentioned, depth of field would be almost nothing. I'm doing good to get a full inch of depth at f16 with the binocular lens setup.

As far as magnification goes, just add more extension tubes. But from the little experimentation I've done I seem to lose some sharpness with extreme tube lengths. I have 3 sets of M42 tubes I can use, for a total of somewhere around 170mm, usually I stick with one set that totals 52mm or so. It also means I have to have loads of light, that much tube length cuts down light gathering considerably. But at one inch, I don't think I could get much light onto the subject without a good ring flash, and that might not even do it. I've never used one so I don't know what its capabilities are. But I do know that with the binocular lens rig, I have to use a folded envelope to reflect the flash onto the subject, it's so close the flash shoots over and past the subject. So lighting would be a big problem at one inch.

03-26-2012, 07:56 PM   #20
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Hi guys, sorry for the late response, just got home from work. I just want to say thanks again for all the help / advice you guys are sharing.

Yeah, I was actually going off on a tangent with my last post about touching the lens. I don't know that I would ever need to do that, although I've seen a couple of amazing shots with the GRD that did just that. Wish I could remember where, I'd link you to them. Anyway, the whole idea of close focus (say, 1" - 2") for me is a matter of perspective and composition. Truly, I don't know enough to articulate what I mean. But it's something that I've had success with, using my old point and shoot. It's just a technique that I've gotten accustomed to. Of course, I am a complete newbie when it comes to DSLR shooting, and I've no doubt about the truth of all of your advice.

I guess the Cliff Notes version of my original conundrum is how to combine near-macro (not necessarily 1:1) with a wide angle perspective. The method I've used with the point and shoot is to get very close to the subject and to use the widest (zoomed-out) focal length. This may or may not be the best method to use with a DSLR. Obviously it depends on the lens set-up. One thing I do believe is that I would prefer a shorter lens rather than a longer, in order to achieve the wide angle view I'm looking for.

Thanks again guys, I really appreciate your help.
03-27-2012, 05:58 AM   #21
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I guess the problem most people are having in terms of meeting your needs are the following, which I have highlighted

QuoteOriginally posted by 97381 Quote
Hi guys, sorry for the late response, just got home from work. I just want to say thanks again for all the help / advice you guys are sharing.

Yeah, I was actually going off on a tangent with my last post about touching the lens. I don't know that I would ever need to do that, although I've seen a couple of amazing shots with the GRD that did just that. Wish I could remember where, I'd link you to them. Anyway, the whole idea of close focus (say, 1" - 2") for me is a matter of perspective and composition. Truly, I don't know enough to articulate what I mean. But it's something that I've had success with, using my old point and shoot. It's just a technique that I've gotten accustomed to. Of course, I am a complete newbie when it comes to DSLR shooting, and I've no doubt about the truth of all of your advice.

I guess the Cliff Notes version of my original conundrum is how to combine near-macro (not necessarily 1:1) with a wide angle perspective. The method I've used with the point and shoot is to get very close to the subject and to use the widest (zoomed-out) focal length. This may or may not be the best method to use with a DSLR. Obviously it depends on the lens set-up. One thing I do believe is that I would prefer a shorter lens rather than a longer, in order to achieve the wide angle view I'm looking for.

Thanks again guys, I really appreciate your help.
I forget now your origonal camera, I think you mentioned samsung, so perhaps you can post again the camera model and the exact lens you have (it may be written on the camera) so we can scale this up to the equivelent format in digital. but just to give you an indication, lets assume your camera has an image circle (diagonal of the chip) of about 0.8cm, then if you consider that the lens on the P&S has a roughly a 7 mm focal length, (or perhaps expressed as 28mm in 35mm equivelent minimum focal length) your 1 inch close focus translates into about 4 x minimum focal length, this translates into less than 1/2 life size on the sensor, and the real equivelent using an ASP-C sensor would be something like a 20mm lens focused at 80 mm or approximately 3 inches working distance.

just food for thought
03-27-2012, 07:07 AM   #22
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When P & S users talk about getting close enough they usually are referring to image size or magnification; in addition to that you are referring to angle of view.

Your new DSLR will do what you want I think. The kit lens at its shortest focal length has about twice the viewing angle as your P & S.
03-27-2012, 07:34 AM   #23
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QuoteOriginally posted by newarts Quote
When P & S users talk about getting close enough they usually are referring to image size or magnification; in addition to that you are referring to angle of view.

Your new DSLR will do what you want I think. The kit lens at its shortest focal length has about twice the viewing angle as your P & S.
In fact the kit lens is probably a wider FOV than the P&S but the real issue I suspect is that the kit lens won't focus close enough. My DAL only focuses about 4.5 inches from the front element, and about 8 inches from the sensor.

03-27-2012, 01:57 PM   #24
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I have a Canon Powershot A70 that is sitting around some where. I also have an SMC M50 1.4. How does one mount that to the Canon P&S? Thx.
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