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05-13-2010, 06:47 AM   #31
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QuoteOriginally posted by yeatzee Quote
How much mag. for just a 28mm reversed?
I tried this. I don't know what magnification, but working distance was zilch and no auto aperture.


Last edited by audiobomber; 05-13-2010 at 07:04 AM.
05-13-2010, 06:59 AM   #32
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QuoteOriginally posted by Digitalis Quote
Pcarfan, I have used that technique a lot myself...I can personally vouch for it's effectiveness. though it can cause a bit of a problem with the reflections from the water on the subject. using a polariser on the flash head and one on the lens can help diminish that though.
I am glad to hear this, as I wasn' too sure whether I was mixing things up a bit there....I just haven't gotten into real macros that much, but after seeing that flickr link, I am very tempted to try extreme macro's.
05-13-2010, 07:20 AM   #33
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I agree with others here that teleconverter is the way to go if you want to have enough working distance for insects that are actually still alive. I've used the SP90 combined with the Pentax 1,7x AF adapter on my ist DS with good results: Close Enough ? on Flickr - Photo Sharing!


If however the insects are dead (or at least rather stuck due to a lot of moist), you can go ahead with some crazy 5:1 macro rig, but you'll have no working distance at all and a non-existant depth of field. I think most MP-E 65 users will tell you it's a real pain to use out in the field. To get enough dof with extreme macro setups you'll probably need to shoot a bunch of images of a static subject while turning the focus ring, and then use suitable software to combine the shots in post, for example Helicon Focus.
05-13-2010, 07:26 AM   #34
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QuoteOriginally posted by audiobomber Quote
I tried this. I don't know what magnification, but working distance was zilch and no auto aperture.
auto aperture at extreme macro is not always helpful. However, this can be worked around by stacking lenses as long as the camera side is an A lens.

05-13-2010, 08:24 AM   #35
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QuoteOriginally posted by Blue Quote
auto aperture at extreme macro is not always helpful. However, this can be worked around by stacking lenses as long as the camera side is an A lens.
IME auto aperture is extremely helpful with macro. I find enough to worry about with nervous critters, constantly changing backgrounds, sun vs shade, flash vs natural light and extreme apertures. It's enough of a disadvantage that it should be mentioned, especially since the OP mentioned a desire for auto aperture.

Yeatzee was specifically asking about reversing a 28mm, not stacking, therefore there would be no auto aperture.
05-13-2010, 08:48 AM   #36
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QuoteOriginally posted by audiobomber Quote
IME auto aperture is extremely helpful with macro. I find enough to worry about with nervous critters, constantly changing backgrounds, sun vs shade, flash vs natural light and extreme apertures. It's enough of a disadvantage that it should be mentioned, especially since the OP mentioned a desire for auto aperture.

Yeatzee was specifically asking about reversing a 28mm, not stacking, therefore there would be no auto aperture.
Yeah he did in his original post mention auto aperture. We have also been discussing Shahan's setup and reversing and stacking lenses. Aperture is critical in controlling depth of field at extreme macro. If A opens it up too much, the depth of field can become too shallow. That's why some sort of macro flash often becomes a necessary evil.
05-13-2010, 10:36 AM   #37
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QuoteOriginally posted by yeatzee Quote
I can't get to flickr on the computer i am on now, so go ahead and use the three linked in my first post Ira though they are not my best.....

Though you are clearly getting ahead of yourself as I said my standards are high, because I have discovered such good photographers such as the ones I linked taking pictures at mag. far greater than 1:1. Not one image in the tammy thread can compare to Thomas or XBN's images IMO.... not even close. Am I "tooting my own horn"? NO! I never claimed my images are even in the same ball park as theirs... but I am striving every day to get there Comparing 1:1 cropped/uncropped tammy images as you said to my images that are greater than 1:1 is hardly "calling a spade a spade."

(do me a favor and read the WHOLE first post. I clearly say I want above ~2:1 so it seemed apparent to me that my comment towards the tammy post of yours was because 1:1 is not what im looking for. When I said my standards were higher IS BECAUSE of people like Thomas... not because im some prideful kid who thinks his images are better than everyone elses )

Id still be interested to here the response though, so go for it Ira! One condition though, post your own fav. 3 macro photo's to compare also Im open for critiques any day of the week. How else am I supposed to be a better photographer?
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QuoteOriginally posted by Ira Quote
Not MINE! I'll post what others have done!
Please read the WHOLE post. Feel free to add other to the mix, but if your so adamant about it you must post three of your own. Sounds fair to me
05-13-2010, 10:38 AM   #38
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QuoteOriginally posted by Blue Quote
Aperture is critical in controlling depth of field at extreme macro. If A opens it up too much, the depth of field can become too shallow. That's why some sort of macro flash often becomes a necessary evil.
Maybe this is a miscommunication. By "auto aperture", I don't mean that you would let the camera automatically control the aperture. What I mean is that you set the aperture and the camera automatically meters the exposure. With a single reversed lens you only have manual exposure, no auto.

05-13-2010, 10:41 AM   #39
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QuoteOriginally posted by Blue Quote
It will depend on whether or not if its a symmetrical or asymmetrical. If it is asymmetrical

Magnification can be calculated by measuring the entrance opening and exit opening.

m = exit/entrance

You can measure that with a ruler.
Not quite sure what you mean, so what about for the K 28mm F/3.5? M 28mm F/2.8?

QuoteOriginally posted by Douglas_of_Sweden Quote
First I must say that you have indeed been posting some very impressive macros. But I understand you perfectly when you try to say that you look for higher standards even though you are not there yourself and might not ever get there. I'm like that myself. Backside is that you never are really happy with your own achievements, even when they are pretty good.

I'm currently using two combos that gives me > 1:1 in combination with good working distance.

SMC Pentax DFA 100mm macro with a 1.7x soligor converter. Gives me up to 1.7:1 with good working distance. That's an AF converter so autofocus still work, and contrary to what is often said about macro, I do find AF usefull now and when with moving subjects.
Same lens but with an extension tube made from a Kenko 2x AF converter where I have removed the glass. From measuring it appears to give me up to 2:1, though I'm not sure how to calculate it:

Also this combo gives me working autofocus. This home made converter even give me AF on SDM lenses.

Dissclaimer: I don't mean any of these shots are near the standards you aim at, but it is at least >1:1 with good working distance.

Besides these I've been experimenting with combos of reversed lenses (up to 20mm lens reversed on a 200mm giving macro 10:1), bellows etc, but nothing I'm prepared to post yet. And they don't give me much working distance.
Thanks! I guess my dilemma with this idea which seems to be the best, is IQ drop. I here all over the forum about how cropping is generally better than sticking on a TC for tele's and I figure with macro I need max. IQ so.....?

QuoteOriginally posted by audiobomber Quote
Here's a good article on calculating macro magnifications. www.peterforsell.com
Thanks audio!

QuoteOriginally posted by pcarfan Quote
If I remeber this right, a forum memeber who posted the most breathtaking set of macros I've evnr seen mentioned something about spraying cold water from a spray bottle to keep the subjects still. I guess that is something to consider.
Yes I remember that also. Now that I have two more days of school left this year, I'll finally be able to wake up early enough to get the bugs nice and still w/out using a spray. We'll see how that goes
05-13-2010, 10:46 AM   #40
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Oh and I forgot to mention why I love reversing my M 50mm on the sigma so much. I lose very little light unlike with my extension tubes AND I can use my flash wirelessly which is the only way to get decent shots at >1:1.

So yes I would much rather be able to do the same for a new setup i.e. reverse a lens on an A lens but I only have one prime A lens so I doubt that will work. A reversed 28mm on tubes seems very interesting as a third setup, and I am willing to buy a cheap ebay off brand PTTL cable to use the flash off hotshoe (though Im sure it will be annoying). As a fourth setup, if someone reassures me that TC's will be great for macro with very little IQ drop that that would be a sensible fourth setup.... right?
05-13-2010, 11:41 AM   #41
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QuoteOriginally posted by audiobomber Quote
Maybe this is a miscommunication. By "auto aperture", I don't mean that you would let the camera automatically control the aperture. What I mean is that you set the aperture and the camera automatically meters the exposure. With a single reversed lens you only have manual exposure, no auto.
You operate the reversed lens in manual mode. You set the aperture on the lens and use the green button. As I said earlier, it starts getting into flash territory which is a whole different can of worms.
05-13-2010, 01:14 PM   #42
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QuoteOriginally posted by yeatzee Quote
Not quite sure what you mean, so what about for the K 28mm F/3.5? M 28mm F/2.8?

This trick should work on them. It is just measuring the size of the only on the entrance side of the lens and exit (mount) side of the lens and dividing. If you stack it on your 105mm, just divide 105/28 = 3.75.
05-13-2010, 03:48 PM   #43
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im realy curious with these stacking lens , but i wonder where i can get this kind converter ?
considering my macro lens is 67 mm ... and M 50 mm is only 49 mm ,,,
05-13-2010, 06:35 PM   #44
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Oh, ok Blue I understand!

I'd say this is relevant

--------------------------------------------------------------------------------------------------------

I took a quick video because I got a lot of questions about my setup on other forums. YES I KNOW I NEED A HAIR CUT! YES I KNOW ITS REAR ELEMENT NOT FRONT! YES I KNOW IM WEARING A LAME FENDER SHIRT DESPITE THE FACT THAT I LIKE GIBSON MUCH MORE....

(it was shot indoors so I wouldn't loose the little guy attempting focus stacking for the very first time.)

05-13-2010, 08:35 PM   #45
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Yeatzee, that's not too far off the concept that T. Shahan is using with his flash other than he has fashioned a bracket for his. I have got a couple of ring flashes I use. I like bracket rigs better, but I get snagged too often.

I need to take some pix of some of my arrangements. with a macro rail, it gives an extra hand hold even if you use it without a tripod. I actually have a little shoulder brace and handle I use for flat to the ground situations. With a bellows, there is a "built in" focus rail.
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