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09-28-2007, 04:51 PM   #16
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QuoteOriginally posted by Bramela Quote
I would suggest that it is a Greengrocer Cicada (or are they only Australian?).
To me, it looked like a cicada indeed, but I didn't know there were some species so small as this one. Thanks for the identification. The picture has been taken in my backyard here in Brunei.

Cheers!

09-29-2007, 01:55 AM   #17
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Here are a few more pictures taken today with the Voigtländer 125/2.5.

Dragonfly eating a freshly caught common fly:


Menacing ant:


Butterfly resting on a fern:


Backlit hibiscus:


Cheers!

Last edited by Abbazz; 09-29-2007 at 03:20 AM.
09-29-2007, 07:41 AM   #18
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All I have to say is - thank god I bought that lens, lol Now I just share a sense of pride in your pics instead of want and desire, lol. I somehow find that eating dragonfly one kinda gross, lolol but seriously - Very nice!

I'm rather considering the 180/4 at this point. Rather a modest set of numbers, but built with the same ED and APO glass as the 125, plus 1.2m close focusing, relative small size and with even slightly higher performance #'s than the 125 at Photozone... and for $355... tempting.
10-13-2007, 08:32 PM   #19
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QuoteOriginally posted by Abbazz Quote
Even with a 125mm at 1:1, you will need a lot of sun or a good flash to shoot at 1:1 without increasing the ISO.
Sorry, this is off-topic, but I have to ask. I've learned a lot over the few months of DSLR ownership, however this is just one thing I haven't caught on to. What exactly does "1:1 subject magnification" mean? And as this is a prime not a zoom, only focus can change... so what is it one is doing to "shoot at 1:1"?

10-13-2007, 09:14 PM   #20
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it means that ant projected on the sensor/film is the same size as its physical proportions. Thats whats meant by 1:1.

a 5mm ant = 5mm picture of an ant on the film plane.
10-13-2007, 09:29 PM   #21
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ah... so then as the sensor with 1.5x crop is a bit under 25mm diagonal that means if you're shooting the ant diagonally the ant's length is taking up about 20% of image frame? .... big! I see (if that's correct that is).

So then I gather "shooting at 1:1" is a function of one's distance from the subject? Is that distance basically the same as minimum focus distance then?

thanx for the info!
11-07-2007, 03:22 AM   #22
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Focusing distance is the distance between the subject and the sensor plane when the subject is in focus.

Regards
Janko

02-25-2008, 07:36 PM   #23
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QuoteOriginally posted by Abbazz Quote
Of course, the depth of field will be thinner with a 200mm than with a 125mm lens. The 200mm allows for greater distance between the lens and the subject, which is a good point for shy critters, but it is much more difficult to handhold than a 125mm or a 90mm. Even with a 125mm at 1:1, you will need a lot of sun or a good flash to shoot at 1:1 without increasing the ISO.

Cheers!
Nope, DoF is actually controlled by magnification and aperture. A 10mm lens and 1000mm lens both at 1:1 magnification on the same canera will exhibit the exact same DoF.
02-25-2008, 09:28 PM   #24
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Thought on 200 Macro

The original question is now moot as the lens has been purchased, but just for interest sake and for others still considering...I own an FA100 f.2.8 Macro which I almost never use as I've stepped up to the A*200 Macro and the FA*200 Macro. For critter work, like reptiles etc. the 200's get the nod b/c of the nice distance at which you can obtain 1:1. As mentioned by another post, the perspective from the 200's allows for much nicer background effects too. The 200's have enough "reach" that I've used them for published photo work taken through the glass at aquariums.

A*200 marries really nicely with the high perf. A 1.4XL teleconverter to get bigger than lifesized images with very little loss of resolution and color. The 1.4XL reduces color, resolution and contrast when connected to a big 600/4 (particularly wide open), but has far less negative impact on the Macro--almost unnoticeable. Note that the FA*200 is not compatible with the 1.4XL--rear element is too close to the mount--1.4XL extends into the lens barrel. So unless the upcoming SDM 1.4 converter is compatible with an FA* Macro, 1:1 is the limit for the FA version (without going to extension tubes and I haven't tried my 1.4 APO Sigma converter with the FA, but that may be an option).

With the longer lenses, diffraction is more of a problem at f22 and beyond--the front of the lens is farther from the blades--or at least that's my nontechnical understanding. At f16, both the 200's are stunningly sharp. At f22 diffraction is noticeable. At f32 on the A*, diffraction is so severe as to ruin the shots. I learned my lesson well enough that I've never even tried the FA* at f32...

If you plan to work primarily with flat field subjects or "still life" subjects, the 100mm range of macros will likely work just fine for you--especially those nonPentax ED or APO models. If you want to work with close-ups of creatures, the extra working distance and minimized backround view from the 200mm range of lenses will earn the cost difference back the first time you work in the field.

For travel, I've found a "poor man's macro" option that really works well. If I can't fly a macro lens with my kit, then a Canon 77mm 500D multi-element close up lens married to an FA* 80-200 makes a great pseudo macro. With a 67mm step up (or is it step down?) ring this close up lens also works very well with the F* and FA* 300 f.4.5 lenses. I also sometimes "cheat" and use it with a Sigma 300 f.4 that I travel as a knock around lens. I even add it to the front of the strange lens shade of the 100 Macro for my 67II to get beyond 1:1. Note that this is in addition to the multi-element close up lens that's part of the 100 Macro already. Yes, that's two close up lenses with a few inches of air gap between them, and resolution is shockingly strong without any nasty color effects that I can see. I don't do this often, but it works!
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