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Widest lens for Pocket Blackmagic camera Bolex anamorphot?


roccoforte

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If you know what is the maximum focal length you can use on your current camera, then you know what you can use on the Pocket. Just calculate everything back to fullframe.

 

For example: my Kowa 2X works on 35mm on my GH2 with 1,86x crop.

35mm x 1,86 = 65,1 (fullframe equivalent)

Divide 65,1 by 3 (cropfactor Pocket Camera) = 21,7mm

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Now I'm not so sure because 35mm on a my T2i vignettes too much:

 

 

T2i

 

50 x 1.6 = 80 (WORKS)

40 x 1.6 = 65 (WORKS)

35 x 1.6 = 56 (VIGNETTE)

 

 

GH2

28 x 1.9 = 53.2 (WORKS w 16/32)

 

BMPC

17.5 x 3 = 52.5 (NOT SO SURE) <----

25 x 3 = 75 (LOOKS GOOD)

 

But is the above calculation the ONLY way of figuring it out?

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It also depends on the design of the lens. Some might vignette more than others, it should be a rough guideline.

 

I'm surprised it works on your GH2 with 53.2mm equivalent, but doesn't work on your T2i with 56mm equivalent.. what 35mm are you using on the T2i?

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The 35mm on the T2i was the Zeiss 2.0 Distagon. Maybe I should try a different 35mm...?

 

RE: the GH2; I was referencing itimjim's post above mine (apologies for the confusion). Which is also a different anamorphot, so that may account for the difference too.

 

It's anyone's guess, I suppose. Just gonna have to drop $1200 to find out!

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Bolex 8/19/1.5x rear element is 20mm

 

ok,.. the rear on my shigascope and izukarscope are smaller, 17mm and 19mm respectively.

 

from here i'll use the focal length of lenses for 35mm still photography to avoid any confusion, so multiply by x2.7 for the field of view:

 

on a nikon v1 cx sensor which has a crop factor of x 2.7, a 28mm takumar vignettes.

 

a 35mm takumar doesnt vignette.

 

i did play with a v1 zoom lens that went from 24-something in the shop and i put my shigascope infront, and it would be ok till about 30mm. after that the vignette starts to appear.

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  • 2 weeks later...

16/32 means it has rear aperture of 32mm and was intended for 16mm film

8/19 means it has rear aperture of 19mm and was intended for 8mm film

 

both are 1.5x and made by Moeller but some say the Bolex ones are higher quality (unproven)

 

there are 2x models also like 30/2x and 32/2x as well as the bigger cinema projection lenses

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