Missing aperture diaphragm (iris) and a buckled blade

**david94903** · 08-12-2020, 10:11 PM

If you reverse mount that 28mm lens on your 50mm lens, you'll have a sweet little 1.78:1 macro setup.

Coupling lenses for extreme macro

zeebanker · 08-13-2020, 10:38 AM

Originally posted by david94903

If you reverse mount that 28mm lens on your 50mm lens, you'll have a sweet little 1.78:1 macro setup.

Coupling lenses for extreme macro

Oh wow! Thank you for that tip, David! Please see attached. Several things to come to mind:
1. The 50mm on the camera has a 49mm filter dia and the Vivitar has a 52mm, so I couldn't actually connect them with a ring (don't have one yet). So I held them together with one hand.
2. I removed the broken iris on the Vivitar (tried to remove just the bent blade, but then everything went kaput, so I removed them all). So the "objective" lens is wide open (35mm F2.8). The Pentax was stepped up (down?) to 2.8.
3. Wow, one needs super steady hands to manually focus in this configuration.
4. What's with the very narrow in-focus area? The sweet spot's like a thin strip across the lens.
5. Quite a bit of vignetting.

Any tips on how to hold the camera steady? I'm quite ecstatic even with these initial results. Am buying an adapter ring right away!

Thanks again! I now have a use for that Vivitar.

**david94903** · 08-13-2020, 12:23 PM

Originally posted by zeebanker

Any tips on how to hold the camera steady?

Practice practice practice, and a lot of luck. Or, a tripod, ha! Depends on what your chasing. Pennies tend to stay put, Bugs like to jump around.

Check out Thomas Shahan. He's a Pentax guy and shot reverse macro for a long time. Along with amazing photos, he gives good advice on patience.

Thomas Shahan - YouTube

08-13-2020, 10:38 AM	#17
zeebanker Forum Member Join Date: Jan 2015 Location: Minneapolis Posts: 58 Original Poster	Originally posted by david94903 If you reverse mount that 28mm lens on your 50mm lens, you'll have a sweet little 1.78:1 macro setup. Coupling lenses for extreme macro Oh wow! Thank you for that tip, David! Please see attached. Several things to come to mind: 1. The 50mm on the camera has a 49mm filter dia and the Vivitar has a 52mm, so I couldn't actually connect them with a ring (don't have one yet). So I held them together with one hand. 2. I removed the broken iris on the Vivitar (tried to remove just the bent blade, but then everything went kaput, so I removed them all). So the "objective" lens is wide open (35mm F2.8). The Pentax was stepped up (down?) to 2.8. 3. Wow, one needs super steady hands to manually focus in this configuration. 4. What's with the very narrow in-focus area? The sweet spot's like a thin strip across the lens. 5. Quite a bit of vignetting. Any tips on how to hold the camera steady? I'm quite ecstatic even with these initial results. Am buying an adapter ring right away! Thanks again! I now have a use for that Vivitar. Last edited by zeebanker; 09-12-2020 at 08:03 PM.

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08-12-2020, 10:11 PM	#16
david94903 Loyal Site Supporter Join Date: Nov 2010 Location: San Rafael, CA Photos: Gallery \| Albums Posts: 806	If you reverse mount that 28mm lens on your 50mm lens, you'll have a sweet little 1.78:1 macro setup. Coupling lenses for extreme macro

08-13-2020, 12:23 PM	#18
david94903 Loyal Site Supporter Join Date: Nov 2010 Location: San Rafael, CA Photos: Gallery \| Albums Posts: 806	Originally posted by zeebanker Any tips on how to hold the camera steady? Practice practice practice, and a lot of luck. Or, a tripod, ha! Depends on what your chasing. Pennies tend to stay put, Bugs like to jump around. Check out Thomas Shahan. He's a Pentax guy and shot reverse macro for a long time. Along with amazing photos, he gives good advice on patience. Thomas Shahan - YouTube