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peter-lowe
Joined: 01 Aug 2006 Posts: 1
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Posted: Tue Aug 01, 2006 3:28 pm Post subject: |
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I have a Crown Graphic 4x5 camera and an old but indestructable 6x7 MF back that slides in to the standard Graflex revolving back.
I am trying to calculate how much of the image area I will lose if I use a 6x7 medium format back loaded with 120 film on my Crown Graphic with my 90mm schneider lens.
Would I get a wider or narrower view than by using the same 120 film in my 6x7 Mamiya 7 MF camera with its standard 80mm Mamiya lens?
And just to make this even more difficult I am wondering how would all this 4x5/MF calculations translate into equivelant 35mm focal lengths - which for me is just like comparing japenese yen and danish kroner by convertting both into good old US dollars.
Hmmm... I guess the easiest way to find out would be to just try to take a photo of exactly the same image with both 4x5 film and 120 film loaded in the 6x7 MF back, then compare the negs and trying to draw guidelines on my 4x5 screen where the neg of the 120 6x7 MF film ends.
But maybe you have more experience and can come up with some useful hints about how I can untangle this (for me) knotty problem.
And to make matters worse - one more (maybe absurd?) question. Is there any type of modified MF back that can be attached to a standard Graflox revolving back that could enable me to capture on my 120 MF film 100% of the image area that I normally capture on 4x5 film.
Hope this is not too many questions,
Peter
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Dan Fromm
Joined: 14 May 2001 Posts: 2120 Location: New Jersey
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Posted: Tue Aug 01, 2006 4:04 pm Post subject: |
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Quote: |
On 2006-08-01 08:28, peter-lowe wrote:
I have a Crown Graphic 4x5 camera and an old but indestructable 6x7 MF back that slides in to the standard Graflex revolving back.
I am trying to calculate how much of the image area I will lose if I use a 6x7 medium format back loaded with 120 film on my Crown Graphic with my 90mm schneider lens.
Would I get a wider or narrower view than by using the same 120 film in my 6x7 Mamiya 7 MF camera with its standard 80mm Mamiya lens?
And just to make this even more difficult I am wondering how would all this 4x5/MF calculations translate into equivelant 35mm focal lengths - which for me is just like comparing japenese yen and danish kroner by convertting both into good old US dollars.
Hmmm... I guess the easiest way to find out would be to just try to take a photo of exactly the same image with both 4x5 film and 120 film loaded in the 6x7 MF back, then compare the negs and trying to draw guidelines on my 4x5 screen where the neg of the 120 6x7 MF film ends.
But maybe you have more experience and can come up with some useful hints about how I can untangle this (for me) knotty problem.
And to make matters worse - one more (maybe absurd?) question. Is there any type of modified MF back that can be attached to a standard Graflox revolving back that could enable me to capture on my 120 MF film 100% of the image area that I normally capture on 4x5 film.
Hope this is not too many questions,
Peter
| Interesting. I didn't know that Crown Graphics had revolving backs. My little 2x3 sure doesn't. Did you mean Graflok?
All kidding aside, why don't you measure the gates and calculate the ratios?
An 80 mm sees a wider angle than a 90 mm lens. So on the same format at the same distance the 80 will cram more in. If, that is, it covers the format.
About the magic back. 120 film is 60 mm high, in a holder ~ 56-57 mm is actually exposed. 4x5 film is ~ 100 mm high, in a holder ~ 95 mm of that is actually exposed. 57 < 95, end of discussion. Were you thinking of a 6x12 back? |
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Rangemaster
Joined: 06 Jul 2001 Posts: 412 Location: Montana, Glacier National Park
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Posted: Tue Aug 01, 2006 6:09 pm Post subject: |
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I have never seen a revolving back either, I know on the Graphic view they have a back that can be taken off and changed from verticle to horizontal format...but have never seen the revolving version, I would be interested in seeing that.
Dave
_________________ Focus on the Picture, Not on the Glass.
Satin Snow(TM) Ground Glass |
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ImageMaker
Joined: 20 Jun 2006 Posts: 93 Location: North Carolina
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Posted: Wed Aug 02, 2006 5:02 pm Post subject: |
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If it has a revolving back and has been mistaken for a Crown, perhaps it's actually a Super?
_________________ Is thirty-five years too long to wait for your first Speed? |
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