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03-25-2012, 12:07 PM   #1
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close focus conundrum

Good day all, I've a conundrum and I need the brains in this forum to help me sort it out.

First I must thank baro-nite for pointing me to RioRico's infinitely helpful "cheap macro" thread, which goes a long way toward answering my questions. I just need to draw out a point or two for further clarification.

My photography experience has to this point been almost exclusively with a small point-and-shoot camera. My just-ordered K-r should be here any day, and obviously I will have a lot of learning to do to put it to good use. That said, I believe I am looking to translate some techniques from the former to the latter.

Point and shoot cameras may be the David to DSLR's Goliath, but one thing I can do with a point and shoot, and which no DSLR has an easy time with, is close focus. With my little old Samsung L100, I can get right up in the face of whatever I'm shooting, and furthermore retain a wide angle of view while doing it. It's a technique that seems to work great for me. I like being right up close to my subject as it always achieves that certain something in the composition and perspective. If I felt really adventurous I could call it "macro panorama". Okay, that's a bit exaggerated, but you get the idea.

DSLRs on the other hand are good at high magnifications from a greater working distance, which inherently creates a much narrower field of view. While I do look forward to achieving some interesting high-magnification shots, I think I am actually more interested in the kind of perspective that comes out of my little Samsung.

So, to the point, what lens setup will get me the closest? I have done much research, and I do realize that I will never exactly duplicate the technique with my K-r. But I do know that I can get close. Thanks again to RioRico's excellent guide, I have discovered the world of enlarger lenses. These seem like a strong possibility. It is my understanding that enlarger lenses were optically engineered for a closer focus than typical SLR lenses, even macros.

Any hints, advice, comments, jokes, limericks or haikus on the subject are greatly appreciated. Thanks for helping an unlearned newbie out.

03-25-2012, 12:33 PM   #2
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I think any of the popular wide angle lenses will give you exactly what you're looking for. I foyu look through the reviews on the lens database most of them will have the minimum focus distance listed. I just did a cursory search and found that most appear to be able to focus as close as 6-12" from the subject. The wide angle will give you the field of view you describe.
03-25-2012, 12:44 PM   #3
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@thebigcat: Thank you for the quick response! I really should clarify what I meant by "close focus".. rather than 6" to 12", how about 1"? Honestly, no sarcasm intended. This is the kind of working distance I'm really looking for.
03-25-2012, 12:48 PM   #4
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I should emphasize again that I understand I am looking for something that just doesn't mesh with large-sensored cameras (i.e. non point-n-shoots). However, I do believe that some creative folks have come awfully close. Again I think it's the enlarger lenses that could be the key. Anyone using one want to chime in?

03-25-2012, 12:50 PM   #5
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Wide angle macro is addressed by Pentax's DA 35 macro lens. It has a wide enough angle to get the results you want though most macro shooters want some distance between the lens and their subjects, hence the popular 50 and 100mm macro lenses.
03-25-2012, 01:36 PM   #6
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Your best bet is probably to reverse mount a lens with a low focal length (e.g., 28mm).

Use extension tubes of the same length to achieve 1:1 magnification or longer to go beyond, thus decreasing the focusing distance.

Alternatively, you can reverse mount a short lend on a long lens. The magnification is then determined by the ratio of the focal lengths (long / short).
03-25-2012, 02:05 PM   #7
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You cannot get high resolution and large depth of field with a large sensor. If you want a wide angle with extension tubes will get you close and wider field of view than standard nacro--but not depth of field. If you choose the smallest aperture (likely f/22) you still will have much less depth of field than with small sensor, and less resolution than if using wider aperture. Suggest you use the K5 with whatever lens you have and then get a feel for what it does. I would say get extension tubes--but if the lense is a modern one w/o aperture ring--it likely will not work.
03-25-2012, 03:03 PM   #8
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Your Samsung L100 has an effective 35mm full frame focal length range of from 37-111mm. The kit lens you'll have with your K-r will have a field of view much wider than your Samsung's widest. That, plus some enlargement may be sufficient for you.

One way to get really close-up with the kit lens is to mount it backwards with a reversing ring but then everything's manual.


03-25-2012, 03:12 PM   #9
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I f the OP mounts the kit lens in reverse, or forward w/ extension, won't it be wide open always? -I don't believe the kit lens has aperature ring.
03-25-2012, 03:14 PM   #10
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Sorry--I just noticed you detailed an external aperature adjust.
03-25-2012, 03:54 PM   #11
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I won't repeat what I wrote in the CHEAP MACRO article (thumbs-up are always appreciated!) but I'll reiterate some of the operative optics principles. Look at the rules of DOF:

* For thicker DOF, use a shorter lens and/or tighter aperture and/or further lens-subject distance.
* For thinner DOF, use a longer lens and/or wider aperture and/or closer lens-subject distance.

Those rules have implications when shooting macro. Because of the very close distance, DOF is always very thin, except with very short lenses. Small-frame cameras (like mini-sensor P&S's) use very short lenses, which can retain fairly thick DOF even when focused close. The 6mm 'normal' lens on my Sony DSC-P20 can get very close indeed, with thick DOF.

Larger-frame cameras (like d/SLRs) necessarily use longer lenses, and even fairly short glass may be almost impossible to use for macros. I put a 10mm-long extension behind my Zenitar 16/2.8 but the focus distance was much too close, inside the lens even! But any close work with a larger-frame camera will have really thin DOF unless the aperture is stopped WAY down -- and then diffraction fuzziness sets in. TANSTAAFL, eh?
_______________________________________

A reasonable way to get close and yet retain fair DOF, as Class A mentioned, is to reverse-mount a fairly short prime, with added extension. Or, reverse-stack a short MF prime onto a longer one. In either case with a reversed prime, your working distance will be around 45mm. Shorter lenses will provide more magnification with less light-eating extension. Example: I stack a 58-PK mount reversal ring, 52-58mm step ring, and Panagor 24/2.8 together, and get 3:1 magnification with minimal light loss.

Reversed zooms are a little different than reversed primes because their working distance will vary with focal length. I haven't shot with a reversed DA18-55 because aperture control *is* tricky with DA lenses. I do shoot with a reversed A35-80/4-5.6, arguably the worst lens Pentax ever produced -- but reversed, it's a decent macro-zoom. Really cheap, too!

A trick for a reversed PK (bayonet-mount) lens: use a short section of cheap PK macro tube as a lens hood.

Anyway, tiny-frame and larger-frame cameras are just different beasts when shooting ultra-close. At least you're not forced to shoot macros with an 8x10" view camera. THAT is a challenge!

Last edited by RioRico; 03-25-2012 at 04:14 PM.
03-25-2012, 03:58 PM - 1 Like   #12
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97381,

With the kit lens, you may be able to get close to the results you are looking for. As DMS suggested, get some experience with it first to determine what you need.

You might eventually consider something like the DA35 Macro as Ash suggested (however, that's not really wide-angle on APS-C, but more a "normal" focal length), or perhaps something like the manual-focus Vivitar 28mm close focus lens. Older manual-focus primes can often be found for relatively low prices.

Enjoy your new acquisition!

-Joe-
03-25-2012, 04:07 PM   #13
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So far as I know there is only one way to get larger DoF for a given macro magnification, effective f-number, and image size & that is to use a smaller sensor; one way to mimic using a smaller sensor is to shoot at lesser magnification then enlarge the image (this uses a smaller portion of the actual sensor.)

I have tried it and it works.
03-25-2012, 05:29 PM   #14
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Hey, some really helpful responses & advise here. It's humbling when the real veterans chime in on the new guy's naive questions.

Couple of points I didn't even mention.. DOF was brought up by you smarter guys and I have not even begun to think about how it comes into play. I suppose it would behoove me to take that into consideration. My inclination is to try to achieve priority #1 of getting really close and then start fiddling with DOF issues. In many cases I might not mind razor-thin DOF but in some cases I might like to get a little deeper.

The other thing I didn't say is that I'm not as concerned about higher magnification as I am with priority #1 (see above). I have generally referred to these types of shots as "macro" but you can take that term loosely. I think the more accurate term is close focus. If you glance at a couple of shots I posted in the "post your photos" forum you'll see what I mean. In fact, in a rare moment of clarity, I titled that thread "not quite macro".

To the several of you who are suggesting reverse mount / short focal length / reverse kit lens.. I'm going with you. All I've read seems to suggest that as the method of choice for what I want to do.

Thanks again guys, this forum rocks.
03-25-2012, 07:38 PM   #15
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I'm not sure if you will find anything that will focus as close as 1 inch. I've worked with a Samsung S 730 P&S, Samsung TL205 P&S and they both focus no closer than about 3 inches, my K-x with 50mm and binocular lens gets me maybe 4 inches at best, but does get pretty good magnification and excellent detail. You can take a look at some of the shots I've posted in the Tiny Flowers thread and see what the binocular lens rig does. It also does pretty well in the depth of field department, if I can shoot at f8 or smaller. Quite often I try to shoot with a flash and push it to f16 or f22 for maximum depth, and that does well.

My only extension tubes are M42 and that limits me to a 135mm Lentar lens for now, minimum focus distance there is about a foot, but again I get pretty good detail and depth of field but as before I Have to get at least f8 aperture to get any decent depth. That usually means either very good sunlight or flash. I can't wait to be able to afford either some K mount extension tubes or a 50mm M42 lens, to try a wider angle lens with extension tubes but the 135 is definitely not wide angle.

I've tinkered with reverse mounting two 50mm lenses and wasn't highly impressed, but it does work. I might need to dig out a couple of hte older lenses and work with it a bit more, but so far I've been very pleased with the binocular lens, so I've been sticking with that.

Whatever you go with though, working with anything that gets really close will seriously limit the depth of field. With the binocular lens rig sometimes I can't get a half inch diameter flower all in focus, especially at larger apertures. So whatever method you go with, give some consideration to lighting. On a good bright day I can use ambient light but in shady or cloudy conditions I have to pull out the flash or forget it. Indoors I can use either of a couple of light setups, but I shoot indoors very seldom so usually it's a variable power flash. But that also lets me get very small apertures and lots of depth.

I would think it might be a good idea also to look through some of the macro shots posted in various threads and check into what equipment was used to get shots in the general range of what you are looking to do. I've seen some excellent shots in the Tiny Flowers thread, some great macros of spiders, and a few abstracts that were pretty interesting too. So do some browsing through some of the forum areas and see what people are doing, then find out what they used to do it.
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