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#11
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extension tubes with macros for critters?
Alan Browne wrote:
MarkČ wrote: Annika1980 wrote: is the use of extension tubes to get closer to the subjects a viable option? Yes. is there a significant loss of optical performance? No, only Depth of Field. -And light loss. Light isn't lost, just spread out more on the film so a longer exposure is required. ;-) Right. I call that light loss. |
#12
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extension tubes with macros for critters?
MarkČ wrote:
Put up yoru dukes, pal! I see your dukes and I raise you three Earls, a viscount and a rather bankrupt baron! -- -- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm -- [SI] gallery & rulz: http://www.pbase.com/shootin -- e-meil: Remove FreeLunch. |
#13
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extension tubes with macros for critters?
"etosha" wrote in news:1140778442.111302.39690
@i39g2000cwa.googlegroups.com: Hi, I'm going to Gabon for a month in the rainforest and I was wondering if you could help me decide whether or not to buy a Kenko extension tube set for my macro lenses. The gear to be used for close-up work is: Minolta Dynax 9 Sigma EX 105/2.8 Sigma EX 180/3.5 Minolta 5400HS flash others: Sigma EX 2x teleconverter, tripod, off-camera flash bracket The 105/2.8 lens focuses to about 31cm but for some smaller critters such as ants this is not enough, and to get in-yer-face pics of caterpillar heads, for example, that simply is inadequate. So the question is: is the use of extension tubes to get closer to the subjects a viable option? is there a significant loss of optical performance? help appreciated, cheers, Marko Lots of little things in here. The 31cm distance is to the film plane, and in reality, this will not change with extension. The front of the lens will be able to get a few centimeters closer, but the kicker is that the lens is moved much further from the body, so the image spreads out more, like moving a slide projector further from the screen. However, with all three Kenko tubes on either of those lenses, the increase in magnification is probably not what you're hoping for. The formula is to divide the extension into the focal length, and this provides the increase in magnification. So, take the 105mm at closest focus, 1:1 ratio (lifesize). Three tubes - 12, 20, and 36mm - gives 68mm, divided into the 105. That gives you 1.54:1, or one-and-a-half lifesize. And much less for the 180mm. At the same time, you have to factor in the light loss (yes Alan, it's a loss, regardless of nonsense semantics), reduced DOF usually requiring a small aperture, and the lens being closer to your subject. What you're likely to find is that, even with a tripod and macro slider, on live subjects in situ, as it were, you are highly unlikely to nail sharp focus, or produce a decent pic without motion blur because you'll need a really long shutter speed. And that's if the subjects let you get that close. You can combine options for greater effect, and there's no good formula for this. I've used macro lenses with a teleconverter *and* extension tubes, and gotten some decent shots from it. Also worked with a TC but no tubes, which produces a better magnification than all three tubes, above. You can also use diopters with any of the above, but be warned - you're severely testing the limits of degradation with such. Your highest magnifications, however, are going to come with lens reversing (mounting a lens directly on the camera body backwards) and lens stacking (mounting a lens reversed on the front of a longer lens). These produce some wickedly high magnifications, and at the cost of producing DOF that can be measured in fractions of a millimeter. When doing reversal work, you'll want a wider angle lens - 28 to 50mm, I usually prefer 35mm. The reason is, you need to cover the film plane with the image, so you need an angle of view (when used normally) that will exceed the width of the film when reversed. Any kind of telephoto will vignette badly - they're normally capturing a very narrow field. Stacking works better with a smaller focal length reversed onto a longer one - 50mm onto a 200mm, or more. Rear focal length divided by front gives increase in magnfification, in this case 4:1 from a lens that would normally be 1:1. Such a method requires very sharp and limited distortion lenses, though, and you're likely to still crop the resulting image to remove aberrations from the edges. For both techniques, both camera and subject will have to be totally motionless, you're probably going to want a cable/remote release and mirror lockup, and lighting becomes a royal pain in the ass. This is primarily "studio" work rather than field work. The "studio" might be a camp table in the woods somewhere, but basically, you're going to need to rigidly control the conditions, and forget about snagging the subject as it goes about its business. The benefit of this is, your studio background can be a twig or a leaf - absolutely nothing else is going to be even slightly in focus (though avoid specular highlights). To that end, you may want to consider taking along collecting bottles (film cans, whatever) full of alcohol to pickle the best subjects, and posing them as needed. Not exactly a non-intervention practice, but then again, your presence there defeats that, and you're probably crushing hundreds when you walk and sit down ;-) Additionally, if you're looking to identify them afterwards, producing the specimen is quite likely your only hope - identifying species, even by trained entomologists, often requires seeing things your photos simply do not show. And you'll have the chance to redo the shots in better conditions if needed. Hope this helps. Good luck, and enjoy your trip! - Al. -- To reply, insert dash in address to match domain below Online photo gallery at www.wading-in.net |
#14
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extension tubes with macros for critters?
Al Denelsbeck wrote:
At the same time, you have to factor in the light loss (yes Alan, it's a loss, regardless of nonsense semantics), reduced DOF usually Humor impariment tuneup due, Al. |
#15
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extension tubes with macros for critters?
To that end, you may want to consider taking along collecting
bottles (film cans, whatever) full of alcohol to pickle the best subjects, and posing them as needed. Dude, that's just WRONG! The whole fun of shooting macro is the challenge of it. It is damn hard to get those little critters in focus while they go about their business. Your technique would be like shooting wildlife by taking pictures of deer heads on someone's wall. |
#16
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extension tubes with macros for critters?
Al Denelsbeck wrote:
To that end, you may want to consider taking along collecting bottles (film cans, whatever) full of alcohol to pickle the best subjects, and posing them as needed. Not exactly a non-intervention practice, but then again, your presence there defeats that, and you're probably crushing hundreds when you walk and sit down ;-) Are you serious? Surely you must realize that a huge degree of authenticity and reward is lost when you kill the subject, and then artifically pose it while dead. Do you find equal enjoyment in viewing pictures of dead insects/animals compared with live specimens in their natural habitat? I don't, and certainly find no joy in the process of photographing stuffed animals/pickled bugs. |
#17
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extension tubes with macros for critters?
"MarkČ" mjmorgan(lowest even number wrote in
news:3wpMf.1693$Uc2.1537@fed1read04: Al Denelsbeck wrote: To that end, you may want to consider taking along collecting bottles (film cans, whatever) full of alcohol to pickle the best subjects, and posing them as needed. Not exactly a non-intervention practice, but then again, your presence there defeats that, and you're probably crushing hundreds when you walk and sit down ;-) Are you serious? Surely you must realize that a huge degree of authenticity and reward is lost when you kill the subject, and then artifically pose it while dead. Do you find equal enjoyment in viewing pictures of dead insects/animals compared with live specimens in their natural habitat? I don't, and certainly find no joy in the process of photographing stuffed animals/pickled bugs. What you need to ask, of all the photographers you see, is how authentic the conditions are in which they shoot. You're probably going to be pretty disappointed. Photography makes no pretense of authenticity. Instead, it serves to record an image. That's all. What you derive from it is your own. And all too often, the photographer contrives to help you along with that. In the event of extremely high magnification shots, looking at details of mandibles, spiracles, and so on, you're highly unlikely to get that "in the wild". Period. Try it sometime. You'll waste a lot of time doing it, and probably won't have much to show, except some very large patches of missing hair ;-) Meanwhile, the guy that shot from a dead subject makes the sale, because the editor or publisher needed to see the detail for the article on antennas. Nothing more. Don't get me wrong - I maintain a pretty strict non-intervention policy with regards to wildlife. I also was an active rehabilitator in the past, served on two committees for rehab programs, wrote several of the manuals for training rehabilitators, and provide routine advice for wildlife issues in my position now. I don't believe in depredation live-trapping, much less hunting for any reason whatsoever, and insist that habitats can not only be shared, we upset a pretty serious balance when we refuse to do so. Stop by an entomologist's office sometime, though. What you're going to find is lots and lots of dead bugs. And that's because there's a distinct limit to how much you can glean from a live specimen in a natural habitat. The various denizens of the "bug" world (because someone is bound to pedantically correct me if I lump everything together as "insects") outnumber all other species combined by a pretty signifcant factor, and get trashed by the millions every day by automobiles, chemicals (including photochemicals), airliners as people travel to "unspoiled" spots, power plants that run everyone's computer, and yes, by simply walking on them blindly. And then, for the philosophically logical, there's also the argument that we're not exactly an introduced species on this planet, so everything we do is also perfectly "natural", just as much as a bird choking down lacewings by the hundreds each night. Or you can go with the various religious arguments that maintain that god put all these species here for our own benefit anyway ;-) (It probably should be noted that these are both arguments I avoid when speaking with people on wildlife issues, since providing anyone with easy justification for depredation actions isn't the best approach when you're aiming for cohabitation). Everyone chooses their own level of comfort. If you prefer to shoot bugs in strict field conditions, go for it - I'm not making anyone do anything else. I do enough field shots, and tabletop habitats as well, and have a new one in the starting stages for this Spring. But if you think what you're seeing in nature photography is all "authentic" and strictly natural, you're being naive. - Al. -- To reply, insert dash in address to match domain below Online photo gallery at www.wading-in.net |
#18
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extension tubes with macros for critters?
Al Denelsbeck wrote:
"MarkČ" mjmorgan(lowest even number wrote in news:3wpMf.1693$Uc2.1537@fed1read04: Al Denelsbeck wrote: To that end, you may want to consider taking along collecting bottles (film cans, whatever) full of alcohol to pickle the best subjects, and posing them as needed. Not exactly a non-intervention practice, but then again, your presence there defeats that, and you're probably crushing hundreds when you walk and sit down ;-) Are you serious? Surely you must realize that a huge degree of authenticity and reward is lost when you kill the subject, and then artifically pose it while dead. Do you find equal enjoyment in viewing pictures of dead insects/animals compared with live specimens in their natural habitat? I don't, and certainly find no joy in the process of photographing stuffed animals/pickled bugs. What you need to ask, of all the photographers you see, is how authentic the conditions are in which they shoot. You're probably going to be pretty disappointed. If I use myself as an example, I disagree...but you will find every immaginable technique out there, I'm sure. While I've had my fun snapping at the zoo from time to time, I find very little joy in it...and when I do it, I identify the setting (as on my Pbase pages). Photography makes no pretense of authenticity. Instead, it serves to record an image. That's all. What you derive from it is your own. And all too often, the photographer contrives to help you along with that. Not this photographer...or Bret...so who are you talking to? In the event of extremely high magnification shots, looking at details of mandibles, spiracles, and so on, you're highly unlikely to get that "in the wild". Period. Try it sometime. You'll waste a lot of time doing it, and probably won't have much to show, except some very large patches of missing hair ;-) There are exceptions in every field. Meanwhile, the guy that shot from a dead subject makes the sale, because the editor or publisher needed to see the detail for the article on antennas. Nothing more. Don't get me wrong - I maintain a pretty strict non-intervention policy with regards to wildlife. I also was an active rehabilitator in the past, served on two committees for rehab programs, wrote several of the manuals for training rehabilitators, and provide routine advice for wildlife issues in my position now. I don't believe in depredation live-trapping, much less hunting for any reason whatsoever, and insist that habitats can not only be shared, we upset a pretty serious balance when we refuse to do so. Stop by an entomologist's office sometime, though. What you're going to find is lots and lots of dead bugs. Of course. And guess what? You would never find me setting up my tripod to take a picture of their dead bugs. And that's because there's a distinct limit to how much you can glean from a live specimen in a natural habitat. The various denizens of the "bug" world (because someone is bound to pedantically correct me if I lump everything together as "insects") outnumber all other species combined by a pretty signifcant factor, and get trashed by the millions every day by automobiles, chemicals (including photochemicals), airliners as people travel to "unspoiled" spots, power plants that run everyone's computer, and yes, by simply walking on them blindly. And then, for the philosophically logical, there's also the argument that we're not exactly an introduced species on this planet, so everything we do is also perfectly "natural", just as much as a bird choking down lacewings by the hundreds each night. Or you can go with the various religious arguments that maintain that god put all these species here for our own benefit anyway ;-) I'd like to tell that to the environmental extremists who bark at me if I try to take a picture of the seals in La Jolla...who have taken over the man-made children's pool (La Jolla cove). They seem to think the seals will explode into a million pieces if they so much as look at me when I'm near them. They equate ANY movement in relation to a human being as "harrassment!" -And I'm not kidding. Ridiculous. (It probably should be noted that these are both arguments I avoid when speaking with people on wildlife issues, since providing anyone with easy justification for depredation actions isn't the best approach when you're aiming for cohabitation). There will always be idiots whe carry thing too far on both sides. I love animals, and hunt only with my camera. For me, that's half the fun...and BTW--capturing a quality shot of ANY animal is FAR more difficult that shooting it. I'm not opposed to controlled hunting, but would simply rather "shoot" with my camera instead of my guns (which I do like to target shoot with). Everyone chooses their own level of comfort. If you prefer to shoot bugs in strict field conditions, go for it - I'm not making anyone do anything else. I do enough field shots, and tabletop habitats as well, and have a new one in the starting stages for this Spring. But if you think what you're seeing in nature photography is all "authentic" and strictly natural, you're being naive. I'm talking only about what I'm talking about. No topic of conversation can withstand every tangential exception one wishes to hurl into a conversation... -Mark |
#19
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extension tubes with macros for critters?
"etosha" vehemently accused in
ups.com: Hi, I'm going to Gabon for a month in the rainforest and I was wondering if you could help me decide whether or not to buy a Kenko extension tube set for my macro lenses. The gear to be used for close-up work is: Minolta Dynax 9 Sigma EX 105/2.8 Sigma EX 180/3.5 Minolta 5400HS flash others: Sigma EX 2x teleconverter, tripod, off-camera flash bracket The 105/2.8 lens focuses to about 31cm but for some smaller critters such as ants this is not enough, and to get in-yer-face pics of caterpillar heads, for example, that simply is inadequate. So the question is: is the use of extension tubes to get closer to the subjects a viable option? is there a significant loss of optical performance? help appreciated, cheers, Marko In my experience, yes, but I have not used bellows nor true macro lenses, even just to compare them to extension tubes. I've used the Kenko 3pc set (and a 12mm Canon, too) with my Canon EOS (Rebel 2000 for years, now a 1N), a mix of indoor/outdoor, but only occasionally on moving things (spiderwebs & flowers in the wind, butterflies, etc.). My usual lens is Canon's 50mm 1.8; I've recently tried a 2x extender (3rd party), which has the advantage of being able to stand further back, but the disadvantage of poorer quality (inherent in extenders, but especially in 2x vs. 1.4x, from what I've heard, so that's my bad). Some observations from using Kenko (& Canon) extension tubes: --Autofocus is not an option. In fact, you'll generally need to move the body to focus at all, ie., set focus on max or min then move the body until you get the (very limited) DoF you want. The min vs. max will give you some intersting differences in magnification. The need to move the whole camera is an annoyance when using a tripod, but might not be so bad if you're shooting handheld. (I don't, 'cuz I'm not steady-handed enough, especially macro). --TTL should give you correct exposure, but your viewfinder image will be dimmer, and your DoF preview will be very dim; the light loss is very significant, also making for longer exposures, which can be problematic if you shoot stopped-down for better DoF. --The extender has another advantage, namely that you may be able to stand far enough away that your hotshoe flash may be useful: popups won't do anything if you're at true macro distance (except maybe cast an odd shadow), and even hotshoe is generally all but useless. I have NOT invested in a ringlight yet, though that is a goal. In my experience, I get the most out of extension tubes when I use a tripod. For flowers or spiderwebs in the breeze that's not so bad, once the wind dies, or even taking a couple frames on the move to get different DoF. Experiment, have fun, and with just a little practice I bet you'll get shots you love. Willa |
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