Close-up pussies, and a ratio question.

-halli-

-halli-

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Can't believe they were still long enough for these pics! MF M42 55mm f1.4 Auto Rikkenon lens with #1,2 & 3 extension tubes. Two off camera flashes. Canon 400D

#1
IMG_6419ppresized.jpg

#2
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#3
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#4
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#5
IMG_6408ppresized.jpg


Now the question - is there a calculator or chart that explains the magnification ratio when using extension tubes?

Hints tips and constructive criticism welcomed please.

#5 is my favourite as it is a bit of a self portrait too! (taken wide open whereas the others were taken stopped right down)
 
Must be the first time I've ventured here...but something caught my eye :thinking:

Intriguing shots btw
 
Good detail, but not sure on the subject?

It looks a litlle spooky to me
 
Definitely a thread title to get the views :LOL:

RE the pics 1 & 3 are excellent (y) but please clone out the flash reflection? ... it doesn't add anything, probably distracting and looks like you have blinded the poor pussy :D
 
Thank you all (y)

Is there something wrong with the title :shrug: :naughty:

Splog said:
RE the pics 1 & 3 are excellent (y) but please clone out the flash reflection? ... it doesn't add anything, probably distracting and looks like you have blinded the poor pussy :D
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Thanks for that, I'll have a go.

The kittens didn't even blink an eye (so to speak) and didn't move for over half an hour. The flash was about 3' away and pointing slightly upwards and the other flash was pointing directly upwards on a bracket attached to the camera.

EDIT TO ADD: I think I'll clone out the eye bogey on #2 too. I'd missed that.
 
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I had a go at cloning out the eye bogey, though not the neatest work - I need more practise.

IMG_6418pp2resized.jpg


Also put a little flare on the flash reflection.
 
To calculate the magnification provided by extension tubes, divide the extension tube's length in mm by the lens's focal length. For instance, if you attached a 75mm extension tube to a 50mm lens, your magnification will be 75 / 50, which is 1.5x magnification.

M.
 
iPhoto said:
To calculate the magnification provided by extension tubes, divide the extension tube's length in mm by the lens's focal length. For instance, if you attached a 75mm extension tube to a 50mm lens, your magnification will be 75 / 50, which is 1.5x magnification.

M.
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Thank you. So I attached a set of 52mm M42 extension tubes to the 55mm lens giving 0.95x magnification. Is that roughly equivalent to 1:1?
 
-halli- said:
Thank you. So I attached a set of 52mm M42 extension tubes to the 55mm lens giving 0.95x magnification. Is that roughly equivalent to 1:1?
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As near as makes no difference :)
 
iPhoto said:
To calculate the magnification provided by extension tubes, divide the extension tube's length in mm by the lens's focal length. For instance, if you attached a 75mm extension tube to a 50mm lens, your magnification will be 75 / 50, which is 1.5x magnification.

M.
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You also need to add the lens native magnification

so a full set of tubes (68mm) on a 100mm 1:1 macro lens

Extension/Focal Length + Native Magnification

68/100+1 = 1.68:1

in practice this usually, just gives a guide as some lens's physical focal length at minimum focusing distance (max magnification) differs from its stated focal length. The most accurate way is to take a picture of a ruler and work it out.
 
Dogfish_magnet said:
You also need to add the lens native magnification. The most accurate way is to take a picture of a ruler and work it out.
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Thanks for the reply. How do I work out the ratio of magnification from a certain lens using a ruler? Some of my lenses have macro ratios written on, but others don't.
 
-halli- said:
Thanks for the reply. How do I work out the ratio of magnification from a certain lens using a ruler? Some of my lenses have macro ratios written on, but others don't.
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Use manual focus and set the lens to minimum focus - take a picture of a ruler by moving the camera to focus. I think your sensor is approx 22mm wide so if you can see 22mm in the photo the lens is at 1:1 (life size), if you see 11mm your at 2:1(twice life size), and if you see 44mm your at 1:0.5 (half life size).

sensor size / mm's seen in photo
 
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Dogfish_magnet said:
Use manual focus and set the lens to minimum focus - take a picture of a ruler by moving the camera to focus. I think your sensor is approx 22mm wide so if you can see 22mm in the photo the lens is at 1:1 (life size), if you see 11mm your at 2:1(twice life size), and if you see 44mm your at 1:0.5 (half life size).

sensor size / mm's seen in photo
Click to expand...

Excellent, cheers (y)
 
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