please help with focus problem - DPChallenge Forums

Canon EF 100-400mm f/4.5-5.6L IS

10/08/2004 10:40:16 AM · #1

I don't know what I am doing wrong. I took some portraits yesterday and the focus on almost all of them turned out very soft. I'm using a 24-70 f/2.8L zoom on my 10D. I focus manually, but use the AF point as back-up, when the shot appears in focus the AF point flashes and beeps.

The example below was taken with a strobe and reflector, 100 ISO, in manual mode - 2.8 aperature, 1/250. I focused on her eyes and they appeared sharp to me. The AF point was over them and indicated the shot was in focus. And of course, I used a tripod.

Any help or suggestions would be greatly appreciated!

Janice

sailracer_98

Canon EOS-6D

10/08/2004 10:46:11 AM · #2

Maybe it is the natural softening inherent to digital? A little unsharp mask in PS may remedy this. I just got a 300D and was pretty unhappy with the sharpness of my Tamron 28-300mm XR lens on my first set of pictures. I had never had problems with slides projected to wall size when using this lens on a film SLR. I just discovered that a light application of the unsharp mask fixed all of the apparent softness that I was seeing.

PS- I haven't tried it yet, but the internal sharpening settings in the camera may be able to improve the shots before taking them out of the camera.

Message edited by author 2004-10-08 10:47:59.

GoldBerry

Canon EOS-5D Mark II

Canon EF 50mm f/1.4 USM

10/08/2004 10:48:01 AM · #3

Personally I think it looks good, some portrait photographers may have other views. I dunno.

Digital has us convinced photos should have this unnatural sharpness, which, is, unnatural. I've been studying famous film photos from the past year or so, and they don't have the sharpness people around here seem to HAVE to have.

superdave_909

Canon EOS-60D

Canon EF-S 15-85mm IS USM

10/08/2004 10:58:23 AM · #4

well as it is, I like the softening in the pic, but that doesn't solve the focus issue. Although it is true you need to do a little sharping
to clean it up a bit, but, coming from this lens you should get good
sharp results. even with out USM.

Koriyama

Nikon D200

Nikon AF Micro-Nikkor 60mm f2.8D

10/08/2004 11:00:53 AM · #5

After viewing the resized for the web photo (which introduces its own sharpening problems), I'd say that it's a bit, just ever so slightly soft. But you're using f2.8 which will only give razor sharpness on the focal point, the rest will be soft. Also, many lens don't perform at their very best at their aperture extremes. You need to do some tests to find out how your particular lens works. Finally, some lens do have focussing problems, and they focus slightly ahead of or behind the indicated focal point in your camera. Test.

siggi

Canon EOS-10D

Canon EF 28-135mm F/3.5-5.6 IS USM

10/08/2004 11:09:58 AM · #6

I agree with Koriyama use a smaller aperture (higher Fnum).
I read somewhere that leses tend to goive sharpest photos at two stops from the largest aperture.
And use USM in post editing.

Message edited by author 2004-10-08 11:15:23.

PaulMdx

Canon EOS-1D

Canon EF 70-200mm f/2.8L USM

10/08/2004 01:59:34 PM · #7

Janice,

Were you using continuous light strobe, or a flash unit?

1/250 should be fast enough to freeze the action, but is there any chance you knocked the camera or your subject wasn't particularly still?

Since you're using the 24-70/2.8L I would rule out the lens quality being an issue here. Increasing the f-stop will help reduce whatever problem you're having, but I don't think it's the cause.

One thing to bear in mind is that the non-centre AF square is not as sensitive as the outer squares, so it may be focus was off. In all honesty, I would just use autofocus, myself..

bbusybee2000

Canon EOS-10D

10/08/2004 02:12:02 PM · #8

on the 10D there is a little wheel up by the viewer. Point your camera at something like a clock that you know is sharp and turn it till it is sharp. It may be that the wheel got bumped so now what you think is sharp is actually out of focus slightly. I had that problem with mine. Not saying that that is your problem but it was something I didn't even know about until my instructor pointed it out.

Pentax DA 18-55mm f/3.5-5.6 AF

10/08/2004 06:30:44 PM · #9

Thank you for the feedback everyone. Perhaps its just inexperience - I'm very new at this. I checked the little wheel and that was ok. I'm going to try using the center AF point to see if that helps, and I really should get a more powerful strobe so I can use smaller aperatures. I'll try using the remote cable too in order to avoid moving the camera in any way. The pictures can be fixed in photoshop (thank goodness) but it would be nice to start with a clean sharp photo.

If anyone else has any ideas please let me know. I took some portraits for a couple of friends and they told some friends and now I have several appointments (for $$$). I've got to figure this stuff out much faster than I anticipated, and get more equipment - so I will probably be asking lots of questions here. I really appreciate the support.

Janice

faidoi

Pentax K10D

10/08/2004 06:43:07 PM · #10

You are using RAW correct? Won't help with focus issues, but better to fix in case.

Message edited by author 2004-10-08 18:44:57.

SDW

Canon EOS-60D

Tamron AF 28-300mm f/3.5-6.3 XR Di LD Aspherical IF for Canon

10/08/2004 06:46:02 PM · #11

Originally posted by sailracer_98:

Thanks for the tip you offered les0910. I just copied the photo and tried what you suggested and it worked great, something to keep in mind when needed on some of my photographs.

Canon EF 55-200mm f/4.5-5.6 II USM

10/08/2004 07:43:05 PM · #12

Originally posted by faidoi:

You are using RAW correct? Won't help with focus issues, but better to fix in case.

Thanks, I am shooting in Raw. I extracted the jpeg files to preview the shots (saves tons of time) and thought that maybe just those files looked soft. But after checking out the raw files they are the same.

orussell

Canon EOS Rebel T6s

10/08/2004 07:52:20 PM · #13

At the resolution of your resized image, Unsharp Mask (Amt. 125%, Radius 0.5, Threshold 1) makes a quite noticeable difference. For best results when printing, use 125%, 1 threshold and adjust the radius to your liking.