Macro lenses

[Dan Fromm]

Thanks for the kind offer. I have my own. I use it to calculate what's possible.

 

[wiltw]

When people start talking about the effects of format on DoF they should be taking about DoF for the same image on film. A shot on "small format" has to be at lower magnification that the same shot on "large format." So, if the two shots are taken at the same aperture the "small format" shot will appear to have more DoF. If, however, the final prints from the two formats are the same size and contain the same image DoF in the final prints will be the same.

That abolutely contradicts what DOF programs, like those from Cambridge Color, tell us about DOF as seen on the same size print from 135 vs. from 4x5...

• 135 format 48mm (2 * short dimension of frame) f/5.6 focused at 5m sees area of 2.48m x 3.71m, and 20/20 vision DOF zone is 1.3m
• 4x5 format 186mm (2 * short dimension of frame) f/5.6 focused at 5m sees area 2.6m x 3.3m (not sure if the program properly uses the actual opening size of film holder), and 20/20 vision DOF zone is 0.3m

If one uses a proportionally smaller aperture on the larger format, which is proportional to the FL used to obtain same AOV, one does indeed get 'same DOF', as is easily shown with APS-C vs. 135 'FF'. In the case of 4x5

• 4x5 format 186mm (2 * short dimension of frame) f/22 focused at 5m sees area 2.6m x 3.3m (not sure if the program properly uses the actual opening size of film holder), and 20/20 vision DOF zone is 1.25m

 

[TareqPhoto]

So now we are contradicting each other about DoF or formulas[equations]? that is why i said i am not good at all in math, in other meaning i hate math regardless it is in everything, and i definitely will not spend long time doing math or calculations to use for my photography.

Well, to make my thread more simple, i m looking for a lens that ca let me getting closed to the subject as much as possible, very close, and for MF it is already answered, and for LF i want to believe it is also answered, but sounds it gets further discussions that including magnification and DoF, so let's say i will ignore magnification and DoF and more thinking about the lens that can let me get closer like i go inside the subject area, or very much filling the frame of smaller subjects/items, is there a such in LF?

 

[Dan Fromm]

• 135 format 48mm (2 * short dimension of frame) f/5.6 focused at 5m sees area of 2.48m x 3.71m, and 20/20 vision DOF zone is 1.3m
• 4x5 format 186mm (2 * short dimension of frame) f/5.6 focused at 5m sees area 2.6m x 3.3m (not sure if the program properly uses the actual opening size of film holder), and 20/20 vision DOF zone is 0.3m

The magnifications are different. The image on 4x5 is not quite 4x as long as the image on 35 mm. Of course 4x5 will have less DoF. Its shot at higher magnification.

Tareq, you've already been told which lenses are available. From here its all up to your budget and what you want to accomplish. Good luck, have fun, buy and read the book.

 

[wiltw]

The magnifications are different. The image on 4x5 is not quite 4x as long as the image on 35 mm. Of course 4x5 will have less DoF. Its shot at higher magnification.

Tareq, you've already been told which lenses are available. From here its all up to your budget and what you want to accomplish. Good luck, have fun, buy and read the book.

The calculations of DOF for any format are generally based upon an 8x10" final print from both images!

 

[Leigh B]

The calculations of DOF for any format are generally based upon an 8x10" final print from both images!

But the magnification required varies significantly based on the film format.

- Leigh

 

[bdial]

In the large format realm, lenses used for reproduction are optimized for close working distances and reproduction ratios around 1:1. But when those sorts of cameras were in common use it typically meant making an A4 sized image of an A4 sized subject, for example.
Those lenses and cameras weren't commonly used for doing something like enlarging a 10mm/.5 inch subject to 8x10 inches though many had enough bellows draw to do it if you wanted. The major limiting factor in large format for making life-size or bigger than life-sized images is the length of the bellows rather than whether or not it can be done optically. The reason that some here have recommended enlarging lenses for large format is that the are optimized for close working distances (relative to a typical pictorial lens), flat fields, and they are commonly and inexpensively available.
In the MF and 35mm realm you have more choices for optics that are designed to make 1:1 or bigger images of small 3 dimensional subjects. The cameras are a little easier to handle at such close distances than LF, and if your goal, for example, is to make an image of a 10mm subject that is double the original size, you can do that easily with 35mm, and there is nothing to gain by doing it in 4x5 except for a lot of wasted film area.

If you need to fill a 4x5 frame with that 10mm subject, then an enlarging lens or a reprographic lens will be somewhat better than a general purpose pictorial lens, but you can do it with ether one of you can extend the bellows far enough (and you have a LOT of light available).

 

[Old-N-Feeble]

In the large format realm, lenses used for reproduction are optimized for close working distances and reproduction ratios around 1:1. But when those sorts of cameras were in common use it typically meant making an A4 sized image of an A4 sized subject, for example.
Those lenses and cameras weren't commonly used for doing something like enlarging a 10mm/.5 inch subject to 8x10 inches though many had enough bellows draw to do it if you wanted. The major limiting factor in large format for making life-size or bigger than life-sized images is the length of the bellows rather than whether or not it can be done optically. The reason that some here have recommended enlarging lenses for large format is that the are optimized for close working distances (relative to a typical pictorial lens), flat fields, and they are commonly and inexpensively available.
In the MF and 35mm realm you have more choices for optics that are designed to make 1:1 or bigger images of small 3 dimensional subjects. The cameras are a little easier to handle at such close distances than LF, and if your goal, for example, is to make an image of a 10mm subject that is double the original size, you can do that easily with 35mm, and there is nothing to gain by doing it in 4x5 except for a lot of wasted film area.

If you need to fill a 4x5 frame with that 10mm subject, then an enlarging lens or a reprographic lens will be somewhat better than a general purpose pictorial lens, but you can do it with ether one of you can extend the bellows far enough (and you have a LOT of light available).

I agree that 135 format has its strengths... macro/micro of small object... very long lenses for sports, astro, etc... quick/easy/stealthy handling for street photography, etc. Large format doesn't excel at any of those but can be used in limited capacity for them.

 

[wiltw]

But the magnification required varies significantly based on the film format.

- Leigh

And the CofC size for any format in any DOF calculator is simply scaled down -- inversely to the degree of magnification required to fill a 8" x 10" print!

• APS-C is magnified by about 13.5X to fill 8" x 10" print; APS-C CofC on film is 0.0156, CofC on 8x10 is 0.2106mm
• FF is magnified by about 8.5X to fill 8" x 10" print; FF CofC on film is 0.025mm, CofC on 8x10 is 0.2125mm
• 4x5 (which is 93mm wide!) is magnified by 2.2X to fill 8" x 10" print; 4x5 CofC on film is 0.094, CofC on 8x10 is 0.2068mm

...IOW the CofC assumption used in one program assumes that the eye sees a blur circle larger than 0.21mm from a viewing distance of 12".

 

[KenS]

Should you need greater DOF for your macro imageing might I suggest that you look into Scanning Light Photo-
macrography where the subject is 'raised-up' through a multiple narrow light beams (4 is probably best) inside a tube. The results will "blow your mind" since there is no 'restriction' on DOF due to the f-stop on the lens.

Ken

 

[Old-N-Feeble]

Should you need greater DOF for your macro imageing might I suggest that you look into Scanning Light Photo-
macrography where the subject is 'raised-up' through a multiple narrow light beams (4 is probably best) inside a tube. The results will "blow your mind" since there is no 'restriction' on DOF due to the f-stop on the lens.

Ken

I 'thought' I invented that process when I was fifteen years old but, as with every idea I've ever had, someone else had already thought of it.