Blog by Bjørn Venø

Blog by Bjørn Venø

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The artist Venø works with photography video and performance. He tries hard at being a licensed fool and has a burning desire to explore beyond our paradigm.

LENS NEARDING

Carnal DesiresPosted by Bjørn Venø Wed, August 13, 2014 16:09:08


Because I believe it is important to understand how your tools work I decided to do a test of my 3 lenses using a googled lens test image.

Canon 24 mm f1.4L USM I (tested f2.8, f4, f5.6, f8, f11 and f16)

Canon 50 mm f1.4 USM (tested f2.8, f4, f5.6, f8, f11 and f16)

Canon 70-200mm f4L USM (tested f4, f5.6, f8, f11 and f16) (tested at 70mm, 100mm, 135mm and 200mm)

When composing the image I placed the test image as close to filling the same amount of frame through out the lenses.

Shutter speed: 1/200

Flash

Tripod

Remotely fired camera

Exposer correction: +/- 0.45 stop at the most - so that all images has a ca centre value of 87 87 87

Forgot to turn of sharpening in Light Room, all images sharpened to: amount 25, Radius 1.0, Detail 25 and masking 0.

White balance correction individually,

- 24 mm shifts from 6550K at f2.8 to 5750K at f16

- 50 mm shifts from 6050K at f2.8 to 5550K at f16

- 70-200 mm shifts 70 mm from 6050K at f4 to 5700K at f16

- 70-200 mm shifts 200 mm from 6050K at f4 to 5700K at f16

- 70-200 mm shifts 135 mm from 6050K at f4 to 5700K at f16

- 70-200 mm shifts 100 mm from 6100K at f4 to 5750K at f16



PREDICTIONS

- Sharpest aperture f8

- Sharpest lens the 50 mm

- Most distortion the 24 mm


RESULTS


24 mm

Is the sharpest lens. Sharpest aperture f8.

The lens with the most vignetting, lens distortion and chromatic aberration

50 mm

The softest lens. Apertures below f4 are significantly softer. Sharpest aperture f8-f16. when compared to 70-200 mm it has least amount of vignetting at the aperture with the most amount, but second worst vignetting at the aperture with the least amount. Second worst for chromatic aberration

70-200 mm

Is the second sharpest lens. Sharpest aperture is f16 through zoom, but softer to the sides, gets exponentially worse. When compared to the 50 mm it has least amount of vignetting at the aperture with the least amount, but second worst vignetting at the aperture with the most amount. Best for not having chromatic aberration except for at 200mm



RESULTS - detailed


- Sharpest aperture

- 24 mm sharpest aperture f8

- 50 mm sharpest apertures f8-16 (f4 and below noticeably soft)

- 70-200 mm sharpest aperture f16 through zoom (centre sharpness the same throughout zoom, going up from 70mm to 200mm the edges get slightly softer)


- Sharpness comparison

24 mm vs 50 mm
- 24 mm is sharper than the 50 mm at aperture f8
- 24 mm is noticeably sharper than the 50 mm in the same apertures below f4
- 50 mm’s f8 is similar to the 24 mm’s f2.8 in sharpness

50 mm vs 70-200 mm
- 70-200 mm’s sharpest aperture f16 is slightly sharper than the 50 mm’s sharpest aperture f8

24 mm vs 70-200 mm
- 24 mm’s sharpest aperture f8 is slightly sharper than the 70-200 mm’s sharpest aperture f16

- vignetting

- 24 mm vignetting apparent below f2.8. At aperture f4 slight black line in bottom right hand corner - reapers, but sutler in aperture f16. Apertures f5.6 and f11 have the lest amount of vignetting, f11 best. f8 seams to have a sutler amount of vignetting.

- 50 mm vignetting apparent below f2.8. At aperture f5.6 same slight black line that appeared in bottom right hand corner of the 24 mm, but not as dominant - it also reappeared sutler at aperture f16. f4 seams to be the aperture with the least amount of vignetting. f8 and f11 the same.

- 70-200 mm vignetting apparent below f5.6. Does not have the black line in bottom right hand corner. Through out the zoom starting at 70mm apertures f8, f16, f16 and f11 have the least amount of vignetting. vignetting becomes more towards 200mm

- Vignetting comparison

24mm vs 50 mm
- Comparing the best apertures for the least amount of vignetting f11 24mm vs f4 50mm - the 50mm has the least
- Comparing the worst apertures for vignetting f2.8 for both lenses - the 50mm has the least


50 mm vs 70-200 mm
- Comparing the best apertures for the least amount of vignetting 70-200 mm has less vignetting throughout out zoom.
- Comparing the worst apertures for vignetting, the 50mm has the least compared to 70-200 mm throughout zoom

- Lens distortion

- 24 mm apparent bulge outwards

- 50 mm Subtle bulge outwards

- 70-200 mm at 70 mm less than the 50 mm - but does change through out zoom - bulges more and more inwards - 100 mm appears to be closest to correct

- Chromatic aberration

- 24 mm, Chromatic aberration not present in the centre, but distinct on the sides, starts appearing ca 5 cm from centre, increases proportionately more towards the edge.

- 50 mm Chromatic aberration not present in the centre, but present on the sides, starts appearing ca 10 cm from centre, increases proportionately more towards the edge.

- 70-200mm Chromatic aberration not present in the centre, but present on the sides at 70 mm, less so 100 mm, non existent at 135 mm, most at 200 mm, starts appearing ca 9 cm from centre, increases proportionately more towards the edge.

- Chromatic aberration comparison

24 mm vs 50 mm
- 24 mm worst

50 mm vs 70-200 mm
- 50 mm ever so slightly worse than 70 mm
- 50 mm worse than 100 mm
- 50 mm worse than 135 mm
- 50 mm better than 200 mm



CONCLUSION

I was wrong about the sharpest lens, but almost correct about the sharpest aperture and correct that the 24 mm had most distortion. I’m not to worried about vignetting, lens distortion and chromatic aberration as it can easily be corrected in raw processing, but sharpness can not be fixed. However I’m concerned about the line that appeared in the bottom right hand corner on the 24 mm and 50 mm at different specific aperture - more investigation required.

24 mm for the sharpest pictures shoot at f8. Avoid aperture f4 because of noticeable black line bottom right hand corner. Use instead of 50 mm when shooting in low light conditions as lower apertures are sharper and likely to have a better depth of field.

50 mm for the sharpest pictures shoot at f8-f16, do not go below f8, f5.6 because of noticeable black line bottom right hand corner. f4 and below because of softness.

70-200 mm for the sharpest pictures shoot at f16, for even sharpness and least amount of vignetting use 70 mm, for best results use tripod.

I was surprised that colour temperature changed depending on the flash strength. Use grey card not only when moving / changing light setup but also when changing aperture.













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Big Norwegian Bales

Carnal DesiresPosted by Bjørn Venø Mon, February 15, 2010 12:09:34
Every one knows that Norway has bigger bales than Sweden.

Yeasterday I created my first Norwegian bales and they were superb. Very rustic. The recipe is highly strait forward.

500 g - mince meat
1 ts - ginger
0.5 ts - nutmeg
1 - egg
salt and pepper

Mix the ingredients together, make the big Norwagian bales in the palm of your wet hands. Then you fry them and put them in juicy Nordic brown sauce.

500 dl - water with stock
2.5 ss - flower
1 dl - milke
1 onion
salt and pepper

Now you can enjoy Big Norwegian Bales with potatoes and carrots without the need to visit Norway or Ikea for sissy Swedish bales.

If you are trully dedicated to Norwegian Bales you will also have to hunt down Lingonberry and Sauerkraut.

Creamed peas are also good with Norwegian Bales

Enjoy ; )



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Who would say no?

Carnal DesiresPosted by Bjørn Venø Tue, April 14, 2009 18:17:19
Who would say no to these lovely girls? I would not. Now why is that? I wonder...

(composite of google image search: female cenobites etc)

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Monsters In Your Room

Carnal DesiresPosted by Bjørn Venø Tue, June 17, 2008 11:18:58
Blog Image(Picture from: http://www.psykosedyr.no)

Among the monsters that hide in the dark cracks of your room, there is a velvet monster with black stripes and fluffy fur. His head however is covered by a black latex skin. He is not tall maybe 30 cm long with pointy ears and sharp white teeth. He often sits on top of the cuberd and watches whilst your hands move over the key board. You might say he has a fetish for keyboards with beautiful female hands floating over them. There are some words and letters he likes more than others, they are not many but when you touch them he gets little tingles in his stomach that make him rumble and show his teeth. Sometimes he falls of the cuberd when you happen to write these words in a certain order. Then he walks up to you and curls him self around your legs like a cat, he even makes a little humming noise. When you are finished typing he goes to his little dark corner and dreams his greatest dream, that you can feel, sea and hear him. However, he knows it can never be true because he is only a fraction of imaginary dust. A drop of water falls slowly from the ceiling and on to his little nose. As it splatters it whispers some words "al dreams can come true even the improbable ones, you must persevere in your search for the key that will open the door to the real world." With a jump, the little monster awakens with what some will cal an evil grin, but those who know little monsters know it is a great big smile of joy.

First writen: 20/08/2004 16:18

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Epiphany

Carnal DesiresPosted by Bjørn Venø Tue, June 17, 2008 01:25:23
I walk through the white void with a thin carpet of mist that swirls with every step I take. Out of the corner of my eye I see elegantly decadent female ghosts indulging in sinful pleasures. I smiles at them, secretly wishing they were touchable, but they are beyond my reality. 

I come to a black stone shaped as an orb with a blue flame in its centre. It is the first physical object I've seen since I left the waking world. I touch the polished surface and feel a slight vibration. The sensation is exhilarating, I touch it with both hands, through my left hand I feel a slow pulsating beat and through the right hand I feel a frantic vibe. My brain starts to interoperate the vibrations as spoken words; I find the stone talking to me most peculiar. 

“You might have good conversations with acquaintances when you meet them her, but most of the people in this domain appear as ghosts and don't sense you because you are a single Dominant Male, you have entered a realm were you are seen upon as a predator with evil intentions and as a threat to the current state of affairs. You must find a female companion.” “But were if not here do I find a companion who can walk on the path I have chosen?” “Now that is the paradox, for you are a reserved, considerate and kind Male who does not take the first move, because he fears rejection, but most of al you don't want to be looked at as if you were a degenerate male. The funniest thing though, is that the girls you are most attracted to are also the ones that are the last to approach any man, since they have no need to. Your paradox is hilarious and something that you share with a lot of men, but what makes me laugh the most is that time and time again you enter this void in the hopes that this time it will be different. But for a few exceptions and snippets it is always the same.” With a cold voice I replay “I know al that, and I know that I must find it within my self to become someone that can charm the type of woman I want to dance across the stars with.” “Indulge me and tell what kind of women do you desire” 

I close my eyes and smile at the fragrance of confidence. “She is a public person, someone who likes to be in the centre of attention and enjoys men looking at her. She is intelligent, reflective and creative with strong personal opinions. But most importantly she is wiling to give her body and soul to the man she chooses. “ The stone laughs to the degree were even the air vibrates. “She is the reflection of your self.” “Yes if I am these things why should I not be aloud to require it from my dance partner? But note this, I don't want a copy of my self, her opinions and interests are not mine” 

“You should lower your standards my boy.” “I'm not going to commit to a girl I can not say from my hart that I love.” The stone goes cooled and with a slow vibration says, “ah… I start to sense something interesting about you here, you desire to frolic with a vast number of girls, but as we've seen your personality does not suit this sort of behavior. However if you find the women you desire, then you will be able to approach the other sex and they will not reject you far from as often as now. So the women you meet can not be jealous, in fact she must enjoy watching you entertain other women, just like you enjoy watching her in the arms of other men and women?” “Yes” “Well good luck to you my boy.”

Silence consumes us as I stand with my hands firmly on the black orb. The ghosts explode in to a climax of decadence, and al my desires flicker in front of my eyes, tantalizing me. But I smile and try to enjoy my place on the fence. The orb brakes the silence, “Some friendly advise, instead of masochistically subjecting your self to this white void, go to the brown rooms instead, for the people their are more approachable.” “Yes I have found a room that I'm comfortable inn and with people that I can identify with” “Then what are you doing here?” “I enjoy the sites, the music and covering my body in rubber.” “You pervert boy you.” “Enough with the boy already, I'm no boy I'm a Man.” “Oh how wrong you are, you will be a boy until you get to release that beast that is within you, boiling away at your flesh.” Finally the orb has found a way to annoy me and I replay angrily. “Obviously that wont happen her.” “With a strut I leave the black orb for reality.” As I leave the blue flame within the orb expands outward, in an attempt to burn me down, but I'm already gone. I'm In my own room, tightly tucked under my covers, I smile knowing two things, one that I'm expanding who I can be for every inch of time that passes by and two that time again I will rise from the ashes.

First writen: Sat 24 Nov 07, 3:50 PM

Blog Image

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