Photographing Models...

[PeteJ]

The lights are florescent "tube" lights covered with tissue paper to diffuse the light. Macro is a must, in my opinion.
So for a "hand me down" camera and $20-$30 I have my booth and camera.
Erick --

Erick- First of all, this is a good shot and great model. If you will bear with me I would like to use it as an example. These comments are definitely not intended to be critical as it is one of the better photos.

This shows very well what you will hear referred to as "depth of field". The center portion of the car is in sharp focus and I assume that was what you wanted to show. You will then notice that that area of sharp focus is limited to that central area. The near tire is out of focus. Starting at the about mid cockpit things get progressively more blurred to the point that the body work on the stand is a fuzzy outline.

The main reason this happens has to do with the aperture opening. The longer the aperture(shutter speed) is open, the larger the depth of field. Some cameras have an photographer controlled shutter speed but many simpler cameras such as phone or tablet cameras do not. If you do have one you can adjust, then the longer the opening the greater the depth of field. The coincidental problem with this is the longer the shutter is open the steadier the camera needs to be.

The other method of dealing with this is to back off and use the telephoto option. As you back up and zoom in, the percentage of the lens you are using becomes smaller and the focus gets better. This is often a good choice for larger areas. Macro focus is good for very small parts, but even if you camera can focus in close, the closer you get the more the object distorts. Straight lines no longer look straight and things look out of proportion.

Erick, again, I am not picking on your picture, just trying to explain some basics of photography. Thank you for letting me use it as an example.

[PeteJ]

I should add a minor but important point when shooting manually, increasing your aperture will bring a greater depth of field.
If you shoot at a greater distance with a zoom lens, it may not matter, but it will matter when shooting with a macro lens or macro mode. The effect is magnified when shooting kits.

I shoot with a m4/3 camera with a 45mm (90mm equivalent) macro lens, and usually use f/8 aperture. It is where the depth of field is greatest and the edge sharpness is greatest (each lens will be different with respect to the aperture/sharpness tradeoff).

More on f-stops
http://en.wikipedia.org/wiki/F-number

btw, dlphnfn, your F189 build is amazing!!!!

Just a very small quibble and this is one that really messes with everyone's mind. You are actually decreasing the aperture by increasing the f-stop number. A decrease in the size of the aperture increased the exposure time and thus the depth of field.

[keithwwalker]

I shoot with a m4/3 camera with a 45mm (90mm equivalent) macro lens, and usually use f/8 aperture. It is where the depth of field is greatest and the edge sharpness is greatest (each lens will be different with respect to the aperture/sharpness tradeoff).

More on f-stops
http://en.wikipedia.org/wiki/F-number

Just a very small quibble and this is one that really messes with everyone's mind. You are actually decreasing the aperture by increasing the f-stop number. A decrease in the size of the aperture increased the exposure time and thus the depth of field.

Yes, that is why the f-stop number should be expressed as a fraction, as I did above, ie, f/8.

Pete also makes the salient observation that sharpness of any lens falls off in the corners, so a zoom can compensate by using a smaller part of the lens center.

Both these effects are graphically explained in a lens MTF chart which charts resolution of the lens spatially.

Briefly the vertical axis is the resolution, the higher being perfect, lower is awful. The horizontal axis is distance from the lens center.

So you can see, in the graphs below that changing the aperture from f/1.4 to f/4 makes the image sharper:

[keithwwalker]

[keithwwalker]

More on MTF charts here:

http://photographylife.com/how-to-read-mtf-charts

[plastiksurgeon]

I just couldn't help but chime in here too, ...Marco and Kieth are right on the money with everything ! I used to shoot models in the studio with a huge (bed sheet size) diffuser above the set diffusing one video light (never strobe/flash) ! After completing the diorama of Estoril 85, I needed cooler light to represent the rainy day the real moment happened during, so I shot outside in the shade on my patio, with no light modifiers at all ! I was so happy with the results, that the studio hasn't been used again since for models ! Marco has it right, ....keep it simple, ...keep it almost costless ! And Kieth has valuable advice about depth of field as well, ....use the smallest aperture possible for the greatest depth of field (f22, f32...etc.), and focus carefully, always, ...ALWAYS on a tripod ! A macro lens or setting makes all the difference about getting close....but I also endorse the "few feet away and a telephoto lens choice" !!!! Michael Portaro at Indycals is another expert model photographer, so check out his site to see his models photographed ! Happy shooting young Jake !

Best,

Steve Mohlenkamp

PS/ Really GREAT shots of really GREAT models (F189 and the Eagle) on this thread !!! ...my compliments for sure !!

[plastiksurgeon]

QUOTE "I shoot with a m4/3 camera with a 45mm (90mm equivalent) macro lens, and usually use f/8 aperture. It is where the depth of field is greatest and the edge sharpness is greatest (each lens will be different with respect to the aperture/sharpness tradeoff)."


I feel the need to disagree with this statement, ...partially, on the basis of physics in optics. THE SMALLEST APERTURE WILL ALWAYS YIELD THE GREATEST DEPTH OF FIELD. F8 on that camera may very well be the sharpest aperture (midrange on any lens is indeed it's sharpest choice), ...BUT, ...f8 , unless it is the smallest aperture on that particular camera is not the greatest depth of field !! Depth of field (focus from here to there...) is greatest as the aperture is reduced in size (bigger numbers), as it is using the very center of the lens, as apposed to the entire front lens surface to gather light. If you hold any lens from the side and look at the profile of the front surface of glass, the glass is curved at the edges to compensate for the distance that light travels, so that you don't have dark corners due to that light having falloff from travelling further to get to your camera sensor than the same light in the middle of the scene. The glass is not as true being curved at the edges, as it in the exact center of the glass element, and when you only utilize the truer "flatter" center of the glass element, depth of field (focus) is expanded. Thus every lens will increase in depth of field(focus) as the aperture is reduced, ...albeit a small (very very small) decrease in sharpness overall, ...but sometimes a small price to pay to have it all in focus !

Best,

Steve Mohlenkamp

[PeteJ]

A very salient point about depth of field. It is something that you can use for different purposes. For instance this is a photo of a die cast I was working on and I wanted to show my client the final outcome of hours of filing and sanding. I wanted the maximum depth of field to show off the work.



Then, to show the work that was not yet done I chose to use a macro with a smaller depth of field to draw the clients eye to the section that still needed work and highlight the pits and file marks. By putting the parts that did not make the point out of focus, it really highlights area that I am showing him without going into a long explanation.


So depth of field is a tool to make a photographic point if you understand how to use it.

By the way Steve, very nice photos. Did you Photoshop in the rain?

[plastiksurgeon]

Absolutely brilliant point Pete about using depth of field as a tool ! We have probably overdiscussed the science of it, but here is the essence of using it to your advantage, ...the art of it !

Thanks also, and yep, the rain is photoshopped !!

Best,

Steve

[smb]

The lights are florescent "tube" lights covered with tissue paper to diffuse the light. Macro is a must, in my opinion.
So for a "hand me down" camera and $20-$30 I have my booth and camera.
Erick --

Erick- First of all, this is a good shot and great model. If you will bear with me I would like to use it as an example. These comments are definitely not intended to be critical as it is one of the better photos.

This shows very well what you will hear referred to as "depth of field". The center portion of the car is in sharp focus and I assume that was what you wanted to show. You will then notice that that area of sharp focus is limited to that central area. The near tire is out of focus. Starting at the about mid cockpit things get progressively more blurred to the point that the body work on the stand is a fuzzy outline.

The main reason this happens has to do with the aperture opening. The longer the aperture(shutter speed) is open, the larger the depth of field. Some cameras have an photographer controlled shutter speed but many simpler cameras such as phone or tablet cameras do not. If you do have one you can adjust, then the longer the opening the greater the depth of field. The coincidental problem with this is the longer the shutter is open the steadier the camera needs to be.

The other method of dealing with this is to back off and use the telephoto option. As you back up and zoom in, the percentage of the lens you are using becomes smaller and the focus gets better. This is often a good choice for larger areas. Macro focus is good for very small parts, but even if you camera can focus in close, the closer you get the more the object distorts. Straight lines no longer look straight and things look out of proportion.

Erick, again, I am not picking on your picture, just trying to explain some basics of photography. Thank you for letting me use it as an example.

Just have to point out that shutter speed has absolutely nothing to do with depth of field, which is solely controlled by aperture for any one lens. The only relationship between shutter speed and aperture is that for a given desired exposure (amount of total light hitting the sensor/film) then as the aperture gets smaller, the shutter speed must get slower. So getting a good depth of field usually means using slower shutter speeds when shooting under artificial light.