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02-24-2010, 09:27 PM   #16
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QuoteOriginally posted by Clarky Quote
I thought I would add that a ring flash is not essential,

I have also used this setup with a homebrew flash bracket with flexible head, A lot cheaper option with a pentax AF200T flash which has manual output controls from 1/8 to full flash.
Neat idea. And you CARRY this?

Kidding aside, this looks like an interesting rig. Oh, so many wonderful possibilities!

david

02-24-2010, 09:31 PM   #17
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Some things to consider:

* The mounted lens (non-reversed, mounted to your camera) should be a prime, not a zoom. IQ will be better, sometime MUCH better. The reversed (stacked) lens MUST be a prime, the faster the better. Unlike a simple diopter lens, the prime you stack is corrected for CA etc.

* For greatest IQ in macro work, just reverse the prime lens - but aperture automation is lost. (And I forget how to calculate magnification.) Or, use extension tubes or a bellows. Such introduce no extra layers of glass between subject and sensor. BUT...

* The advantage to having a reversed prime, or a diopter lens like a Raynox, or a reverse stack (which functions as a high-octane diopter lens) is that you don't lose nearly as much light as with long extension tubes or bellows. High magnifications with a diopter or stack are much easier to see in the viewfinder, than thru a long extension. Also, stacks are more convenient, and diopter lenses are MUCH more convenient. Long extensions can produce vignetting.

* Stacking is a handy way to justify keeping lenses you might otherwise discard. The mount doesn't matter, just the front thread size. So I have a Meyer 100mm I'll mount on the K20D, and a broken-mount Petri 55mm I'll stack on it. Or maybe that Canon 24mm I can't get rid of. Or one of those Leitz or Minolta or Contax lenses taking up storage space. YAML (yet another macro lens).

* How to calculate the amount of magnification? This formula works, regardless of sensor/frame size:
magnification = focal length of prime lens, divided by the focal length of the reversed lens.
Example: 100mm forward lens\ 50mm reversed lens = 2X or double life size

[ grabbed from a prior thread: https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/40742-calculat...rsed-lens.html ] This assumes that the mounted prime is directly on the camera mount, with no extensions or bellows. I'd give the formulas for calculating magnification based on total distance and lens setup, but I can't find my copy of FIELD PHOTOGRAPHY. Darn. I thought I'd unpacked that?!?

Last edited by RioRico; 02-25-2010 at 05:21 AM. Reason: addition
02-24-2010, 10:01 PM   #18
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This was shot on film with a fairly extensive rig.
The LX had a bellows attached to it, and then a 150mm lens was put on the bellows and a 28mm lens was reversed onto that. It is a picture of my old CRT computer screen.
The dot pitch is .22mm if that helps calculate the magnification.

Last edited by Wheatfield; 02-05-2011 at 08:44 PM.
02-25-2010, 07:22 AM   #19
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If you want to get into shooting bugs you should really check out the galleries and forums at
www.photomacrography.net...Front Page

06-06-2010, 04:55 AM   #20
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Instead of making a new thread, i thought it would be better to post this question here...


How many shooters using the reverse lens stack method, use the hood on the first lens to protect the second reversed lens (if it fits over of course) ?

Ive been playing with this macro method recently and was just concerned of protection of the second lens.

Last edited by TOUGEFC; 06-06-2010 at 05:00 AM.
06-06-2010, 12:12 PM   #21
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QuoteOriginally posted by TOUGEFC Quote
How many shooters using the reverse lens stack method, use the hood on the first lens to protect the second reversed lens (if it fits over of course) ?
Not me, but I haven't been stack-shooting outdoors much in risky conditions. I think the most vulnerable part of the secondary lens would be its exposed base, and an extended hood isn't going to help much there. That's probably a good reason to use expendable glass as the secondary when shooting at the beach etc.
06-06-2010, 01:33 PM   #22
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QuoteOriginally posted by RioRico Quote
...the most vulnerable part of the secondary lens would be its exposed base...
A rear lens cap with its bottom removed (or an opening in its bottom) can serve as a "hood."
06-06-2010, 08:20 PM   #23
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QuoteOriginally posted by SOldBear Quote
A rear lens cap with its bottom removed (or an opening in its bottom) can serve as a "hood."
Hey, great idea! I'm not real big on chopping up the few extra rear caps I've paid money for, but I have a plastic bottle cap here with a fat ~42mm thread, just right for those old Takumar secondaries. So I pull out the old Exacto knife and start cutting away... ugh, it's slow and tedious, and I'm poking holes in the book cover I'm working on (Paint Shop Pro 9 User Guide) but it's cheap, so I keep going... and AHA! Now my secondaries are trojanized! In bright orange!

06-06-2010, 09:24 PM   #24
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Yes great idea i too have a couple old used rear caps lying around i might cut the bottom out of. At least it will offer some protection.
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