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Veteran
The beauty of a Petzval is the hemispherical shape of the plane of focus. What's in focus is in a bowl shaped plane. The center is dead sharp and the focal plane extends out tword the camera when you get out from the center just a bit. It produces rapid falloff of focus. The swirls result when you use a lens that's designed to cover a smaller format and use it on a larger format.
I shoot collodion and have three antique petzvals. Check the link at the bottom. It will take you to my RFF gallery and look at the three portraits of individuals. The lady, my wife, wearing the top hat was shot on 8x10 black glass and my 13" Darlot Petzval. The gentleman wearing the derby was on quarter plate black glass and a #2 Ajax Petzval used. It was roughly 10" in FL. The 13" Darlot is somewhere around f4-4.5 and the Ajax around f4 if I remember correctly. Some of the toys in my gallery were shot with a RR lens and some with a Petzval.
It's going to be interesting to see how this remake compares in look. Just like modern glass different makers produced different series of lenses with different looks.
A little history on petzvals, they were the preferred and state of the art during the civil war. They were fast in aperture and cut exposure times drastically. To give an idea of exposure times I have a formula for collodion I came up with and it's relatively fast. The portrait of my wife using the 1860's Darlot 13" shooting in heavy shade was 25 seconds wide open. The aperture is somewhere between f4-4.5. Later lenses that followed the Petzval design were rapid rectilinear sand generally had a maximum aperture of f8. The advantage was a flat plans of focus and smaller.
I shoot collodion and have three antique petzvals. Check the link at the bottom. It will take you to my RFF gallery and look at the three portraits of individuals. The lady, my wife, wearing the top hat was shot on 8x10 black glass and my 13" Darlot Petzval. The gentleman wearing the derby was on quarter plate black glass and a #2 Ajax Petzval used. It was roughly 10" in FL. The 13" Darlot is somewhere around f4-4.5 and the Ajax around f4 if I remember correctly. Some of the toys in my gallery were shot with a RR lens and some with a Petzval.
It's going to be interesting to see how this remake compares in look. Just like modern glass different makers produced different series of lenses with different looks.
A little history on petzvals, they were the preferred and state of the art during the civil war. They were fast in aperture and cut exposure times drastically. To give an idea of exposure times I have a formula for collodion I came up with and it's relatively fast. The portrait of my wife using the 1860's Darlot 13" shooting in heavy shade was 25 seconds wide open. The aperture is somewhere between f4-4.5. Later lenses that followed the Petzval design were rapid rectilinear sand generally had a maximum aperture of f8. The advantage was a flat plans of focus and smaller.