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walter g
Joined: 20 Feb 2010
Posts: 2463
Location: NC, USA
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 Posted: Mon May 10, 2010 11:34 pm Post subject: Another macro question |
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walter g wrote:
I bought a set of tubes from Roxsen. When mounted to my Spiratone 400mm f6.3, I can get my minimum focus down to about 3'. Is there a formula to figure out what length tubes you would need to use to give 1/1 on any given lens.
Also what is the point where light loss exceeds function.In other words how long can I go without adding additional lighting.
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Main cameras
Panasonic G5,Nikon J1,Pentax Q10,Sony Nex 6
Minolta MC W SI 2.5/28, MD 2.8/28, MC W SG 3.5/28, MC Celtic 3.5/28, MC W HG 2.8/35, MD Celtic 2.8/35, QE 4/35, Rokkor X 2/45, MC Rokkor X PG 1.4/50, MC Rokkor X PG 1.7/50, MD Rokkor X 1.7/50, MD 2/50, MC Rokkor PF 1.7/55, MC Rokkor PF 1.9/55, Auto Tele Rokkor PG 2.8/135, MC Tele Rokkor QD 3.5/135, TC 4/135, MC Celtic 4/200, MC Tele Rokkor PE 4.5/200
MD 28-70 f3.5-4.8, MD Macro 35-70 f3.5, Md 70-210 f4, MD Rokkor X 75-200 f4.5, MD 100-200 f5.6
Nikon Nikkor 4/20, O Auto 2/35, S Auto 1.4/50..... Miranda Auto 2.8/28, Auto 2.8/35, Auto 1.4/50, Auto EC 1.4/50, Auto 1.8/50, Auto EC 1.8/50,Auto 1.9/50, Auto 3.5/135
Various Soligor,Sun,Fujita,Komura,Spitatone, etc. Lenses
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kds315*
Joined: 12 Mar 2008
Posts: 16657
Location: Weinheim, Germany
Expire: 2021-03-09
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| Posted: Mon May 10, 2010 11:42 pm Post subject: |
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kds315* wrote:
1:1 needs 2xfocal length between object-lens and same lens-sensor (*). Not sure that will work for your long lens due to mechanical issues.
(*) this works only for simple lens designs, complicated ones may have a much shorter back focal length, so you may have to make some tests....
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"S'il vient a point, me souviendra" [Thomas Bohier (1460-1523)]
http://www.macrolenses.de for macro and special lens info
http://www.pbase.com/kds315/uv_photos for UV Images and lens/filter info
https://www.flickr.com/photos/kds315/albums my albums using various lenses
http://photographyoftheinvisibleworld.blogspot.com/ my UV BLOG
http://www.travelmeetsfood.com/blog Food + Travel BLOG
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Currently most FAV lens(es):
X80QF f3.2/80mm
Hypergon f11/26mm
ELCAN UV f5.6/52mm
Zeiss UV-Planar f4/60mm
Zeiss UV-Planar f2/62mm
Lomo Уфар-12 f2.5/41mm
Lomo Зуфар-2 f4.0/350mm
Lomo ZIKAR-1A f1.2/100mm
Nikon UV Nikkor f4.5/105mm
Zeiss UV-Sonnar f4.3/105mm
CERCO UV-VIS-NIR f1.8/45mm
CERCO UV-VIS-NIR f4.1/94mm
CERCO UV-VIS-NIR f2.8/100mm
Steinheil Quarzobjektiv f1.8/50mm
Pentax Quartz Takumar f3.5/85mm
Carl Zeiss Jena UV-Objektiv f4/60mm
NYE OPTICAL Lyman-Alpha II f1.1/90mm
NYE OPTICAL Lyman-Alpha I f2.8/200mm
COASTAL OPTICS f4/60mm UV-VIS-IR Apo
COASTAL OPTICS f4.5/105mm UV-Micro-Apo
Pentax Ultra-Achromatic Takumar f4.5/85mm
Pentax Ultra-Achromatic Takumar f5.6/300mm
Rodenstock UV-Rodagon f5.6/60mm + 105mm + 150mm
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RioRico
Joined: 12 Mar 2010
Posts: 1120
Location: California or Guatemala or somewhere
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| Posted: Tue May 11, 2010 1:54 am Post subject: |
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RioRico wrote:
Mag = (TE/FL)-1 where TE is Total Extension and FL is Focal Length
So, 50mm extension on a 50mm lens gives TE=100 and Mag=(100/50)-1 =1.
And 150mm tubes with a 50mm lens gives TE=200 and Mag=(200/50)-1 =3.
So to get to 1:1 with a 400mm lens, you need 400mm of extension.
I've done that -- put a 400mm tele on a 200mm bellows with 200mm of tubes on my half-frame 35mm Olympus Pen-FT, all supported on a shoulder mount. (I took closeups of rattlesnakes from a safe distance.) And I used fast film, because the light loss is severe.
EA = FS * (Mag+1) where EA is Effective Aperture and FS is F-Stop
So with any lens at 1:1, if the aperture is at f/11, EA = 11*(1+1) = f/22.
And with a lens at 2:1, if the aperture is set to f/8, EA = 8*(2+1) = f/24.
And with a lens at 4:1 and the aperture is f/16, EA = 16*(4+1) = f/80.
Welcome to Ansel Adams territory. Watch out for diffraction limits.
Magnification eats light. Trying to shoot macros with a long lens requires lots of light. There ain't no free lunch. There are REASONS most macro work is done with 28mm and 50mm and 100mm lenses. If you really need distance (like my rattlesnake shots) then fine, just be prepared.
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Too many film+digi cams+lenses, oh my -- Pentax K20D, K-1000, M42s, more
The simple truth is this: There are no neutral photographs. --F-Stop Fitzgerald |
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walter g
Joined: 20 Feb 2010
Posts: 2463
Location: NC, USA
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| Posted: Tue May 11, 2010 2:13 am Post subject: |
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walter g wrote:
Thanks, this does help.
RioRico, Pretty much the same deal. Instead of rattlesnakes,It's aligators.
I want to get really good closeup shots safely.
_________________
Main cameras
Panasonic G5,Nikon J1,Pentax Q10,Sony Nex 6
Minolta MC W SI 2.5/28, MD 2.8/28, MC W SG 3.5/28, MC Celtic 3.5/28, MC W HG 2.8/35, MD Celtic 2.8/35, QE 4/35, Rokkor X 2/45, MC Rokkor X PG 1.4/50, MC Rokkor X PG 1.7/50, MD Rokkor X 1.7/50, MD 2/50, MC Rokkor PF 1.7/55, MC Rokkor PF 1.9/55, Auto Tele Rokkor PG 2.8/135, MC Tele Rokkor QD 3.5/135, TC 4/135, MC Celtic 4/200, MC Tele Rokkor PE 4.5/200
MD 28-70 f3.5-4.8, MD Macro 35-70 f3.5, Md 70-210 f4, MD Rokkor X 75-200 f4.5, MD 100-200 f5.6
Nikon Nikkor 4/20, O Auto 2/35, S Auto 1.4/50..... Miranda Auto 2.8/28, Auto 2.8/35, Auto 1.4/50, Auto EC 1.4/50, Auto 1.8/50, Auto EC 1.8/50,Auto 1.9/50, Auto 3.5/135
Various Soligor,Sun,Fujita,Komura,Spitatone, etc. Lenses
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RioRico
Joined: 12 Mar 2010
Posts: 1120
Location: California or Guatemala or somewhere
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| Posted: Tue May 11, 2010 3:30 am Post subject: |
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RioRico wrote:
| walter g wrote: |
| Pretty much the same deal. Instead of rattlesnakes,It's aligators. I want to get really good closeup shots safely. |
The safe way: Remote control. Put a camera on a little helicopter, or (waterproofed) in a little boat or sub, with wireless control and data links. If the gear gets chomped, you still walk away safely.
The rig I described above? A "safe distance" with rattlesnakes is 12+ feet / 4m or so. That is NOT a safe distance for crocs and gators, not unless you're in an agile powerboat. A couple years ago I toured Sumidero Canyon in Chiapas (the Grand Canyon of southern Mexico) in a jet launch. We got to within 5m / 16 feet of some crocs. That was almost too close. Those guys can MOVE! But the pilot powered us to safety. And I only had a 135mm lens mounted!! No good closeups... but I got away. Whew.
Of course, if your subjects are in a zoo or gator farm or otherwise safely constrained, then 12 feet should be OK, hopefully. You're insured, right?
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Too many film+digi cams+lenses, oh my -- Pentax K20D, K-1000, M42s, more
The simple truth is this: There are no neutral photographs. --F-Stop Fitzgerald |
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FernandoB12
Joined: 26 Apr 2009
Posts: 231
Location: Rio de Janeiro, Brasil
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| Posted: Tue May 11, 2010 3:33 am Post subject: |
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FernandoB12 wrote:
RioRico
Thank you so much.
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Camera: Nikon D80 Canon 20D Pentax Spotmatic
Manual Lens: Nikkor 24mm f/2.8; Nikkor Ai 50mm f/1.4; Nikkor 50mm f/2.0; Nikkor Micro AI 55mm f/3.5; Nikkor H 85mm f/1.8; Nikkor P.C 105mm f/2.5; Nikkor Q 135mm f/2.8; Nikkor P 180mm f/2.8; Nikon Series E 75~150mm f/3.5;
SMC Takumar 50mm f/1.4; SMC Takumar 55mm f/1.8; Super Takumar 85mm f/1.9; Takumar S-M-C 120mm f/2.8; Takumar S-M-C 200mm f/4; Tele Takumar 300mm f/6.3
Vivitar Series 1 Macro 105mm 2.5
Helios M44-4 58mm f/2; Soligor 350mm f/5.6; Soligor 135mm f/2.8;
AF Lens: AF-S Nikkor 18-135mm f/3.5-5.6 G ED; AF Nikkor 70-210mm f/4-5.6; |
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walter g
Joined: 20 Feb 2010
Posts: 2463
Location: NC, USA
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| Posted: Tue May 11, 2010 4:15 am Post subject: |
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walter g wrote:
They swim around the ship USS North Carolina at Willmington.I haven't been down there yet,but I'm hoping to soon.
Hopefully I will bring back some decent pictures, from a safe spot.
_________________
Main cameras
Panasonic G5,Nikon J1,Pentax Q10,Sony Nex 6
Minolta MC W SI 2.5/28, MD 2.8/28, MC W SG 3.5/28, MC Celtic 3.5/28, MC W HG 2.8/35, MD Celtic 2.8/35, QE 4/35, Rokkor X 2/45, MC Rokkor X PG 1.4/50, MC Rokkor X PG 1.7/50, MD Rokkor X 1.7/50, MD 2/50, MC Rokkor PF 1.7/55, MC Rokkor PF 1.9/55, Auto Tele Rokkor PG 2.8/135, MC Tele Rokkor QD 3.5/135, TC 4/135, MC Celtic 4/200, MC Tele Rokkor PE 4.5/200
MD 28-70 f3.5-4.8, MD Macro 35-70 f3.5, Md 70-210 f4, MD Rokkor X 75-200 f4.5, MD 100-200 f5.6
Nikon Nikkor 4/20, O Auto 2/35, S Auto 1.4/50..... Miranda Auto 2.8/28, Auto 2.8/35, Auto 1.4/50, Auto EC 1.4/50, Auto 1.8/50, Auto EC 1.8/50,Auto 1.9/50, Auto 3.5/135
Various Soligor,Sun,Fujita,Komura,Spitatone, etc. Lenses
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RioRico
Joined: 12 Mar 2010
Posts: 1120
Location: California or Guatemala or somewhere
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| Posted: Tue May 11, 2010 4:39 am Post subject: |
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RioRico wrote:
FernandoB12, you are welcome.
The math for calculating close-up factors is fairly simple. Knowing some algebra is very useful. My source for the calculations is an old text: FIELD PHOTOGRAPHY, Beginning and Advanced Techniques, by Alfred A Blaker (WH Freeman, San Francisco, 1976), a Scientific American book. If you wish to be official photographer on an expedition, read this volume.
I should mention another tool for shooting dangerous subjects: a monopod or hiking staff with a camera-thread screw on the end. I use a Trek hiking staff, a Sony DSC-V1 camera, and a 6-ft / 2m wired remote control. I can hold the staff and camera off a balcony, over a crowd, up to a cage, etc. I'll miss the camera if it is chomped, but not as much as I'd miss my arm.
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Too many film+digi cams+lenses, oh my -- Pentax K20D, K-1000, M42s, more
The simple truth is this: There are no neutral photographs. --F-Stop Fitzgerald |
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