sensor size limitation?

[alphonsis]

I've been trying my hand at some glamour type headshots and I'm having trouble with getting nice sharp eyes.

My settings are f/8, iso 200, 1/200 using a tammy 17-50 2.8.

I can't decide if I'm just missing the focus and getting soft shots, or if it's the lens to blame, or a technical limitation of my body (xti).

At these settings, my dof should be 1.8 feet so it's hard to believe I'm missing the focus. I also have my body set to not do any sharpening in camera.

However, when I lasso out the eyes and apply a little usm 200, 0.4, 0 they start pixelating.

Could someone share 100% crops of eyes shot on a 1.6x body?

Thanks!

[Strayz]

links to samples please...

[alphonsis]

oh sorry, I posted this at work so I don't have access to my samples.

Which is also why I asked if other people could share their 100% crops of eyes for comparison. I'll be able to post mine in about 4 hours or so.

[alphonsis]

Here's an example 100% crop of an eye from a recent shoot.

http://farm3.static.flickr.com/2528/3951379483_191b567bd1_o.jpg

[midnight_rider]

Something is not right with that. Trust me your sensor size has nothing to do with that. A P&S can get sharper than that without a problem. Can you post the photo? Not a crop but the full original image?

[alphonsis]

I don't have a place that will host a full resolution file. I have a free flickr account so I can't post originals.

[midnight_rider]

I don't have a place that will host a full resolution file. I have a free flickr account so I can't post originals.


Not a full res file just an uncropped one would be good. That way it would be easy to see if you are front or rear focusing in the frame.

[alphonsis]

100% crop at max res flickr will allow, got as much of the face in as I could.

http://farm3.static.flickr.com/2533/3951436217_2a1853776a_o.jpg

[AxxisPhoto]

Try stopping down to f13. I get good results there.

[jblaschke]

With that Tammy's reputation, you should be getting razor-sharp images at f4, much less f8 and f11. Something's wonky with the lens. Have you tested it out for front/back focusing issues? Even it has issues, with the depth of field you're shooting at you should have crisp images.

I don't have experience with the Tammy 17-50, but The Wife has a 28-75. Both lenses are supposed to be near-equal in quality, and the 28-75 gives fantastic results, so I'm thinking your lens needs servicing. The XTi is a fine camera, and isn't the problem.

[midnight_rider]

100% crop at max res flickr will allow, got as much of the face in as I could.

http://farm3.static.flickr.com/2533/3951436217_2a1853776a_o.jpg


I was hoping for an uncropped shot. I am curious to see if you are front or rear focusing.

[basroil]

Part of that is slight oof, you'll need to check calibration or technique. Second part is lack of sharpening, a bit of smart sharpen can fix it up quite nicely.

[woodsters]

looks as if you are using the umbrellas from the reflection in the light...try going down to 1/125...I was using 1/200 before with my xti and the same tammy lens upon a recommendation and watched a video where the guy kept saying 1/125th so I tried it and it seems to work better for me ...also might be slight shake or movement...are you doing it by hand or tripod?

[alphonsis]

Thanks for all the suggestions so far.

I guess it's time to rent another lens to see if the lens is the problem.

I am shooting hand held, but at 1/200, I assumed that shake wouldn't be a problem. I'll try again with a tripod just to be sure.

You're right that there's no sharpening, I was just hoping that it'd be sharper straight out of the camera.

@midnight rider: sorry if I misunderstood you. So you want the full shot, but down-sampled? (since I can't post the full res shot due to flickr's resolution limitation)

[midnight_rider]

Thanks for all the suggestions so far.

I guess it's time to rent another lens to see if the lens is the problem.

I am shooting hand held, but at 1/200, I assumed that shake wouldn't be a problem. I'll try again with a tripod just to be sure.

You're right that there's no sharpening, I was just hoping that it'd be sharper straight out of the camera.

@midnight rider: sorry if I misunderstood you. So you want the full shot, but down-sampled? (since I can't post the full res shot due to flickr's resolution limitation)

Is there anyway that you can find someone local to you so you so not have to pay to rent a different lens?
And yes It would help to see the entire image. I do not mean every MB of it just the full frame

Also do a search for focus test. Most people just place a few batteries in a line and take a photo of them at a 45 degree angle to see if their lens if focusing properly.

[alphonsis]

Ah, thanks for the suggestion. I'll try that tonight. Now that you remind me, I have seen that done before.

As for locals, I don't know any local photographers. And as for friends, I'm the only one who uses canon!

[midnight_rider]

Ah, thanks for the suggestion. I'll try that tonight. Now that you remind me, I have seen that done before.

As for locals, I don't know any local photographers. And as for friends, I'm the only one who uses canon!

It seems like I have seen many, many . many members on this forum from the bay area in Cali.
You should start a thread and seek them out. maybe even start a photography club in your area and have access to tons of glass. :idea:

[midnight_rider]

Is THIS (http://photography-on-the.net/forum/showthread.php?t=753331&highlight=bay+area)near you?

[Mark1]

I can post one from my 50D and Tammy later... Im at work now. It is pretty sharp. Especially for the exposure it was taked at.

[alphonsis]

ooooh!

It's about an hour south, but that sounds like fun!

thanks! I should check out the other parts of this forum more often. ^_^

[alphonsis]

I can post one from my 50D and Tammy later... Im at work now. It is pretty sharp. Especially for the exposure it was taked at.
can you make sure it's not sharpened in camera or in post?

thanks!

[sunking39]

Are you using mirror lock up?

[Mark1]

Forgot about this thread.

Here is a 100% clip and the original shrunk down for reference.

Both straight conversion from raw. 0 adjustments.

http://ind-img.com/images/clip.jpg

[alphonsis]

good lord that is really sharp...

now to figure out if it's my body or my lens.

Thanks Mark!

[RDKirk]

However, when I lasso out the eyes and apply a little usm 200, 0.4, 0 they start pixelating.

Actually, a Canon image should take quite a bit more USM than that, unless you're sharpening it in raw conversion or in the camera. Even Canon advises a lot more than that.

Back off from 100%--view the results of sharpening at 50% or even 20% to get a better impression of what a print would look like. Your images look to me as though they need more sharpening in post.

[alphonsis]

Back off from 100%--view the results of sharpening at 50% or even 20% to get a better impression of what a print would look like. Your images look to me as though they need more sharpening in post.
I guess I was imagining that a "sharp" lens would be fairly sharp with no in-camera sharpening and no post sharpening.

Perhaps I was deluded. :)

[Mark1]

It can be fairly sharp in camera. But a digital picture, by its nature, needs some sharpening in post. Even a "sharp" picture can be improved with a bit of help.