Technical question about a portrait by M. Quinn Jacobson

[john_vandale_]

Hi everyone!

My mind's stuck on this beautiful and well-known photograph by M. Quinn Jacobson:




Can someone explain me how to achieve such a short dof?

I saw a few videos where this plate is hanging on the wall. It doesn't seem to be a huge monster plate...

Is it the lens opening/distance factor only or is there any kind of tilt movement? Something like tilted down plus on one side? What's the lens used on this serie?

Thank you very much for your help!

[Drew Wiley]

I dunno anything about the guy. But note how much blacker the deeper tones are around the relatively in-focus face versus the torso etc, which makes me think something greasy was smeared on the neg or contact glass.

[Willie]

Looks as if it may be a longer than normal lens, straight shot, wide aperture for the shallow depth of field.
Don't think Quinn uses much movement for straight portraits.

[Drew Wiley]

The neck is stretched forward, placing the face on a different focal plane.

[williaty]

It's also done on wet plate collodion which means an unusually fast (for LF) lens was likely used. f/3.6-ish is probably the slowest that's likely to be.

[Pere Casals]

Hi everyone!

My mind's stuck on this beautiful and well-known photograph by M. Quinn Jacobson:




Can someone explain me how to achieve such a short dof?

I saw a few videos where this plate is hanging on the wall. It doesn't seem to be a huge monster plate...

Is it the lens opening/distance factor only or is there any kind of tilt movement? Something like tilted down plus on one side? What's the lens used on this serie?

Thank you very much for your help!

Short DOF can come from a long lens, a wide aperture and a close subject, in that shot there are some 30mm DOF, here you can find combinations: http://www.dofmaster.com/dofjs.html

That particular DOF look it's easy to obtain with very big plates or negatives. If you shot 16x20" plates (like Quinn) narrow DOF in portraits isn't difficult, what would be dificult it's the counter

You can use old brass monster petzals (and other). Here Kurt Moser shows the entire process in a TV show (min 1:30):

https://www.youtube.com/watch?v=7Cbg58F98Uw
https://www.youtube.com/watch?v=HmBkXmWgScg

Long process lenses can also be used http://www.galerie-photo.com/apo-pro...ikkors-en.html

Cameras can be really big, you may want a truck to make one for an APO NIkkor 1780mm; https://www.lightcatcher.it/#Ural


You can also take an SLR or DSLR with a nikon or canon 50mm f/1.2, (or even 1.0 for canon) and make a digital negative/positive for alternative process printing, look won't be excatly the same but if the thing ends in a tintype then many people may see the same, anyway something shot with ULF format really big plate is very special, if one has the criterion to feel it.


PD: It looks that there is no tilt or swing movement, because the plane of focus looks well perpendicular to the front axis. Both eyes are in focus and at the same distance, so no swing, also focus in the lips and in tthe the forehead also looks at the same distance, so no tilt. When tilt/swing used then the plane of focus is not perpendicular to the view direction, with movements you can swing and tilt the plane of focus as you want.

Here you can see a shot with tilt : https://www.flickr.com/photos/colton...125592977@N05/

You see the head is in focus, behind subject the floor is out of focus, but the wall in the back is again in focus (the up side), this is because the plane of focus it has been inclinated with a tilt.

[john_vandale_]

Short DOF can come from a long lens, a wide aperture and a close subject, in that shot there are some 30mm DOF, here you can find combinations: http://www.dofmaster.com/dofjs.html

That particular DOF look it's easy to obtain with very big plates or negatives. If you shot 16x20" plates (like Quinn) narrow DOF in portraits isn't difficult, what would be dificult it's the counter

Theorically (DOF Master), my 4.5/210mm @1.5 meter would give me 40mmDOF on my 4x5 plates. But the results are much more commons!

Attachment 175365

[Pere Casals]

Theorically (DOF Master), my 4.5/210mm @1.5 meter would give me 40mmDOF on my 4x5 plates. But the results are much more commons!

Attachment 175365

John,

One important thing to add is OOF roll off nature !!!

To have the same framing than in 4x5/210mm if you shot with a 16x20" camera you would be using a 840mm lens.

You may set an aperture in the 840mm to have the same 40mm DOF you mention, in that range the image will be the same, considering format equivalent CoC (circle of confusion).

but the way the image gets more blurred as it goes beyond the dof range should be different.

Sometimes I used an smartphone app to learn how a lens/distance/aperture will roll off in the OOF, see here how it shows the CoC grows :



This is why you see a different OOF nature from what you see from a 4x5, if I'm not mistaken...

PD: as Totias also points...

[williaty]

John,

One important thing to add is OOF roll off nature !!!

To have the same framing than in 4x5/210mm if you shot with a 16x20" camera you would be using a 840mm lens.

You may set an aperture in the 840mm to have the same 40mm DOF you mention, in that range the image will be the same, considering format equivalent CoC (circle of confusion).

but the way the image gets more blurred as it goes beyond the dof range should be different.

Sometimes I used an smartphone app to learn how a lens/distance/aperture will roll off in the OOF, see here how it shows the CoC grows :



This is why you see a different OOF nature from what you see from a 4x5, if I'm not mistaken...

PD: as Totias also points...

What app is that?

[Pere Casals]

What app is that?

https://play.google.com/store/apps/d...achs.dof&hl=es

you can add new custom cameras of any format, etc

"A compatible version of DoF is also available for Windows computers at:" www.dl-c.com/DoF