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Old Dec 31, 2009, 11:09 AM   #11
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A Macro lens will allow you to focus closer to the subject. This allows you to get a 1:2 or 1:1 size ratio. In other words the bug you are shooting is life size or bigger in the photo and sharply focused...very sharply focused as most macro lens are the sharpest lens you can get.

An extension tube will allow you to use other lens than a macro for macro shooting or as we did in the old days you can get an adapter to reverse a normal lens and use it for macro shots.

Manual focus is best for macro shots and a tripod is highly recommended. Moving in and out you'll find is good to set the shot within the lens minimum focus distance, but use the focus ring to get the final focus.

You'll find the focus ring on most manual focus macro lens takes a lot of turning to change the focus as the focus ring uses much finer threads for a finer focus. Also the depth of field is much flatter and very thin. This means the focus area will be small and the out of focus area much larger so focusing correctly and using a higher f/ stop number to increase the depth of field will come into play. It all can be frustrating but when it all works out it is very satisfying indeed.
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Old Dec 31, 2009, 6:24 PM   #12
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Quote:
Originally Posted by TCav View Post
I've been trying to get onto the Pentax website, trying to confirm that Pentax actually does put a focal plane indicator on their dSLR bodies, but I've been getting error messages each time. From your response, I guess they don't.
On the K7 it is the ring with the horizontal line through it, located to the right of the top display panel. It is not on Pentax digital bodies made prior to this model

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Old Dec 31, 2009, 7:19 PM   #13
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On the K7 it is the ring with the horizontal line through it, located to the right of the top display panel. It is not on Pentax digital bodies made prior to this model.
That's the one. Thank you.
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Old Jan 1, 2010, 11:17 PM   #14
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..sorry
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Old Jan 2, 2010, 12:47 AM   #15
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I am excited to receive my new purchase, the K7, in a couple of weeks' time and I'll match it with a macro such as the Tamron 60mm (though having 2nd thoughts on that and may end up with the 90mm instead).

However even basic cameras can often achieve interesting macro results. These two photos are from a Sony HX1 (2nd is 100% crop) so imagine what you can achieve with a 200D or K7 and the right lens. Can't wait !

This crab was less than 2" across.




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Old Jan 2, 2010, 4:43 AM   #16
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TCav, You got me really interested so I Googled "Focal Plane Indicator" and came up with some hits that were on Film SLR's and found out what it looks like anyways. See, I did learn something. You guys are Great !

bigdawg, Very nice pic's. Thats something I Haven't been doing because of the worry about defraction and my little 6 MP sensor (I've been stayin at about f/8-11 on my K100 Super). I'll try some at f/16-22 just to see what happens. I might have been over-estimateing the defraction damage to the picture as I haven't done any real testing to see what would happen at higher settings. I tried to check out the Exif on your butterfly (?) shot but didn't get any useful info from it. What lens did you use in those pic's ?

penolta, Thanks for the info on the K7, at least I wont be taking off my lens to see if Pentax had put that indicator inside the body of my K100 Super.

Frogfish, pictures like yours are what made me go with a Sigma 50mm Macro to begin with, I was taking similar shots of flower pistols (is that what you call the inside center of flowers, pistols ?) with my canon A520 in Macro mode and saw what could be done with a D-SLR when I first came onto this site. I think they were some of robar's Macro shots with the Viv-105mm if I'm not mistaken. I'm not sure of the minimum focusing distance of the Tamron 60, but my Sigma 50mm Macro says 7.4 inches but to get to the 1:1 scale I have to zoom OUT the lens all the way which leaves me (I finally did a measurement last night) only 2 inches from the front of the lens to the subject, if I have the lens hood attached I have 1 inch. thats pretty tight. I think I'm gonna go with either a Tamron 90mm (Thanks to the Great Pic's from EddyinGA), or for about $20 more a Sigma 105mm Macro.

Thank You all very much for your kind responses

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Old Jan 2, 2010, 10:37 AM   #17
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As far as using small apertures with macro lenses - they are made to use at smaller apertures, so there's no problem using those higher numbers. I use f16-f18 mostly with the Viv, otherwise the dof is way too small. You can get away with using larger apertures with the 50 mm because your depth of field is bigger (50 mm at 2 inches would have a dof of approx. 1 inch, while it would be something like .05 with a 100 mm, assuming I figured out my dof calculator right). So there are trade-offs when buying a longer lens for macro use.
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Old Jan 2, 2010, 11:29 AM   #18
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mtngal - I've just been reading a few reviews of the Tamron / Sigma / Tokina and quite a number make mention of the exceptional range of DOF of the Sigmal 105 mm for its focal length. Is there some other factor at play here ?
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Old Jan 2, 2010, 11:31 AM   #19
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Also, please try an extension tube on your macro lens, before you spend money on a newer lens. This may be all that you need to increase the focal length of your 50 mm macros lens. Inexpensive macro tubes will not have any aperture or auto focus functions, but those will give you a good idea on what kind of distance you could achieve with larger telephoto macro lenses. Just my 2 cents worth.

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Old Jan 2, 2010, 1:05 PM   #20
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I'm no expert, but from what I've read, depth of field is based on optical characteristics of the camera and focal length of the lens. In other words, two 50 mm lenses, focused at the same distance on the same camera with the same aperture set, will give you the same depth of field. I could be wrong about that, but that's my understanding.

Adding an extension tube (one without optics) doesn't change the focal length of the lens, it just allows you to focus closer. They are great when you have a non-macro lens and want to experiment with macro. On the other hand, a teleconverter (i.e., something with optics, such as a 1.4 TC) does increase the focal length of a lens. From what I understand, they don't change the focus distance - I had thought about getting one to increase the magnification I could get from the Viv 105 without changing the focus distance (which extension tubes, dioper filters and reversing a lens in front of it does). I never followed through with buying one so haven't actually tried it. In any case, none of these solutions would increase the focus distance.
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