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P1X4R
09-26-2008, 07:31 PM
i thought i would start a thread that discusses techniques on getting our images the best overall sharpness from all areas for a statue/bust. the biggest challenge has always been getting that depth of field just right to get all parts of the subject in focus. generally the obvious technique is to bump up the f/stop which helps but sometimes doesn't get an arm that extends forward or a sword that points away.

i've recently looked into advanced techniques such as "focus stacking" and tilt shift lenses.

focus stacking is a method by which you take several, manually focused images and let a software program combine them into one complete image with all areas in sharp focus. tilt shift lenses (which by the way is an expensive option) allows you to control the depth of field by "tilting" and "shifting" the focus plane. it's also used in architectural shots to correct building lines to appear more straight vs the "falling" effect you normally would see in person.

SquiderM3
09-26-2008, 09:18 PM
Ed, if anyone knows about sharpness, it's you.

Lead the way master.:thumbs2:

P1X4R
09-26-2008, 09:45 PM
you're already a master my friend. i'm learning from you now.

http://sideshowcollectors.com/forums/images/smilies/bow.gif

CharlesSong
09-27-2008, 06:42 PM
http://sideshowcollectors.com/forums/images/smilies/bow.gif

HoldyourfireAl
09-27-2008, 07:21 PM
This is a dumb question, but shooting at F2.8 vs. F14 won't make an image sharper, correct? F14 will just get more of the subject & surroundings in focus, right? I'm finding that to get a FS Bowen looking sharp all over, I need to use an F14.

P1X4R
09-27-2008, 10:21 PM
going from F2.8 to F14 will definitely increase overall sharpness. a common term for this is "stopping down" vs the opposite of "opening up". the effect though is that your background will also come into clearer focus (depending on subject placement and background distance). just something to keep in mind if your objective is to focus on the subject and not to distract it from the background.

as for F stops.. i tend to shoot roughly around F/8 to F/11 for "optimum" lens sharpness. each lens will be different of course. btw, most of my shots are on a tripod so if you shoot at these apertures handheld then you should make sure to have enough lighting or very steady hands. :)

patman
09-27-2008, 11:36 PM
great pointers from the masters! thanks!

Upitnik
09-28-2008, 04:36 AM
If you want to get "anal" about it there is also something to pay attention to. The fraction of the depth of field which is in front of and behind the focus distance does change with focal length.
Let say you're shooting at 10mm the depth of field distribution would be roughly 70% at the rear and 30% at the front.

At a 100mm the distribution would be about 52% against 48%.

In real world life that means if the before mentioned arm of a statue is pointing toward the camera like Bowens Bisleys Venom you would be wise to use a longer focal lenght and vice versa applies.

On the other hand, when standing in the same place and focusing on a subject at the same distance, a longer focal length lens will have a shallower depth of field (even though the pictures will show something entirely different). This is more representative of everyday use, but is an effect due to higher magnification, not focal length. Longer focal lengths also appear to have a shallow depth of field because they flatten perspective. This renders a background much larger relative to the foreground even if no more detail is resolved.

Savvy? :)

P1X4R
09-28-2008, 10:44 AM
good point! i've actually shot with a 300mm prime indoors with fantastic results but it limits where i can shoot. :D

HoldyourfireAl
09-28-2008, 03:49 PM
here's mine guys! lovely! :thumbs2:

http://i259.photobucket.com/albums/hh285/P1X4R_2008/Bowen/Captain%20America%20Faux%20Bronze/IMG_3280.jpg

Mine...

http://i280.photobucket.com/albums/kk180/HoldyourfireAl/Statues/08%20Sep%2023%20Faux%20Bronze%20Captain%20America/c8ea5ef7.jpg

Look at the difference! I'm using a Canon XSi with a 60mm macro lens. P1X4R is using a Canon EOS 5D and (?) lens. What an AMAZING difference! His is sooooooooooooo much sharper than mine!

Mandragora
09-28-2008, 04:15 PM
lets also not forget that how something is lit greatly affects the sharpness :D

CharlesSong
09-28-2008, 04:39 PM
Right, lighting helps. There are a bunch of factors contributing to the end 'sharpness' result.

-Focus is obviously HUGE
-How steady your camera is
-How much light is on the subject
-What lens you are using
-How much sharpening you add in post


As far as camera bodies go, don't sell your XSi short. Here's a shot just the other day I did with my XT-- yes, that ancient entry level 8 megapixel dinosaur.


http://img201.imageshack.us/img201/9287/lsharp1iu4.jpg


Here's a 100% crop of the eyes:

http://img165.imageshack.us/img165/245/lsharp2gm2.jpg

I haven't added any sharpening in post yet (will do so if I print it)

HoldyourfireAl
09-28-2008, 04:39 PM
So, you think mine would be close to Ed's sharpness in the same lighting that he is using?

HoldyourfireAl
09-28-2008, 04:40 PM
How do you add sharpening to a pic with Photoshop?

HoldyourfireAl
09-28-2008, 04:51 PM
My attempt at sharpening w/ PS...

http://holdyourfireal.smugmug.com/photos/382218098_KMHXJ-X2.jpg

http://holdyourfireal.smugmug.com/photos/382229566_hbjNb-X2.jpg

Mandragora
09-28-2008, 04:51 PM
Right, lighting helps. There are a bunch of factors contributing to the end 'sharpness' result.

-Focus is obviously HUGE
-How steady your camera is
-How much light is on the subject
-What lens you are using
-How much sharpening you add in post




not only that . . .

- the color of the light . . specifically how much does the color compliment/contrast the color of the subject
- the quality of the light (sharp, soft, how strong the contrast)
- how much reflection/type of reflection

all of this makes a huge difference

HoldyourfireAl
09-28-2008, 04:53 PM
Ed...what lighting are you using dude?

P1X4R
09-28-2008, 05:24 PM
Ed...what lighting are you using dude?

Al, i'm using a Canon 580EX II Speedlite mounted on the 5D. it's pointed straight up to bounce flash off the ceiling. i also have another 580 that i can use as a slave/light umbrella combo but i was too lazy to set it up today.

P1X4R
09-28-2008, 05:29 PM
chuck and erin are totally right. it's not always about the camera. lighting, camera steadiness, and a little post processing helps.

chuck, your model shots are always awesome!! i envy your skills! :buttrock:

let's not forget erin's mastery of light and shadow! :thumbs2:

P1X4R
09-28-2008, 05:34 PM
- the color of the light . . specifically how much does the color compliment/contrast the color of the subject


i need to study how lighting works. i've got my flash set to auto but i know i can control it more. i like how it produces a nice, natural and "neutral" color tone. i've taken test shots with and without flash and noticed that the shots taken without flash tend to be warmer and i'd have to fix it in post process.

Mandragora
09-28-2008, 05:54 PM
chuck and erin are totally right. it's not always about the camera. lighting, camera steadiness, and a little post processing helps.

chuck, your model shots are always awesome!! i envy your skills! :buttrock:

let's not forget erin's mastery of light and shadow! :thumbs2:

:wink2: :wink2:

don't forget that you are a master yourself ed

Mandragora
09-28-2008, 05:55 PM
i need to study how lighting works. i've got my flash set to auto but i know i can control it more. i like how it produces a nice, natural and "neutral" color tone. i've taken test shots with and without flash and noticed that the shots taken without flash tend to be warmer and i'd have to fix it in post process.

that's because your lights are emitting a lower color temperature. in my setup i use different gels to compensate for that

http://en.wikipedia.org/wiki/Color_temperature

http://en.wikipedia.org/wiki/Color_gel

Mandragora
09-28-2008, 06:01 PM
a good way to see how direct light affects focus is to watch a football game where half the field is in sunlight and half is in shadow . .

sure, the cameraman will typically adjust his iris for the shadowed parts of the field . . . . , but even when they are in full sunlight you can see that because of all the glare and reflection the shot isn't quite as sharp as it is when the players are in shadow

of course, i don't have HDTV so maybe its different in that case