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View Full Version : Test my lens and solution required



Yisehaq
10-05-2009, 07:23 AM
hey all,

After experiencing alot of problem on sharpness, I have decided to test my equipments. For now, I am testing my lens.

I used the following technique suggested by jlabel. :thankyou:

lens sharpness-how to test (http://www.photography.ca/Forums/newreply.php?do=newreply&p=26632)


The best way to check technical focus is using your camera on a tripod and focusing and shooting a ruler, chose a number and shoot it if the focus is misplaced it may be a lens problem, some newer cameras have the option to configure this kind of problem, also you will be able to see if your lens is sharp enought for you, you should also use f/5.6 or f/8 for this test.

Additional info.

I used a tripod, mirror was locked up and all shots were taken using a cable release. The focus point was [20] on all the shots.
No PP what so ever.

My lens is Sigma APO 70-300mm F4-5.6 DG MACRO
My camera is Canon 350D

what do you think?

Marko
10-05-2009, 10:20 AM
To me the "20" does not look tack sharp.

What format were they taken in (RAW/JPG)

IF they were shot in RAW, did you sharpen them at anytime before you uploaded them?

IF they were shot in JPG, did you sharpen them at anytime before you uploaded them?

Thx - Marko

Yisehaq
10-05-2009, 10:28 AM
Thanks for your reply Marko,



To me the "20" does not look tack sharp.

What format were they taken in (RAW/JPG)

IF they were shot in RAW, did you sharpen them at anytime before you uploaded them?

IF they were shot in JPG, did you sharpen them at anytime before you uploaded them?

Thx - Marko

It was shot in JPG. No post processing what so ever done on this pictures. They are just out of the camera. May be only cropped.

tirediron
10-05-2009, 10:50 AM
The problem with this method is that the target, the [20] is not square to the film plane, so your images are suffering from a parallax error. The best way to do this would be to repeat it, using a series of vertical targets such as matchboxes in a staggered line.

Marko
10-05-2009, 04:18 PM
Although T.I. is correct, it would have been better if both camera and subject were on the same plane, I'm not convinced that's the problem.

Do you know if your camera is sharpening the images? There should be a setting in the menu that tells you if any sharpening is going on.

If no sharpening is going on, that may be it. In my experience (though I only shoot RAW) digital images need to be sharpened.

any other opinions? Thx! Marko

EJC
10-05-2009, 05:48 PM
Here is a more elaborate test with instructions. Focus Test (http://regex.info/blog/photo-tech/focus-chart#intro)

I hope this helps

cheers

Greg_Nuspel
10-05-2009, 09:24 PM
Here is a more elaborate test with instructions. Focus Test (http://regex.info/blog/photo-tech/focus-chart#intro)

I hope this helps

cheers

You beat me to it

Yisehaq
10-06-2009, 02:19 AM
Thanks all of you.




Do you know if your camera is sharpening the images? There should be a setting in the menu that tells you if any sharpening is going on.

There is a setting parameter 1 which has sharpening scale +1. These days, I only use RAW for any purpose.

I tried to use Focus Test but couldn't get it exactly. I will give it a try once more.

Marko
10-06-2009, 11:56 AM
I don't understand Yisehaq.

Why did you shoot these in Jpg if you ALWAYS shoot RAW?

We need to eliminate variables 1 at a time for ease. You should test the camera/lens by shooting in RAW because that's the way you normally shoot.

i think there's a strong chance this is a simple sharpening issue.

I'd like to see 2 shots shot in raw and converted to JPG.
- On a tripod with a cable release
- both camera and subject on a flat plane

- 1 shot you'll sharpen (in photoshop or GIMP etc.) and one shot you won't. What PP software do you use?

Yisehaq
10-07-2009, 02:37 AM
Thanks Marko




Why did you shoot these in Jpg if you ALWAYS shoot RAW??

I didn't know that the file types affect the sharpeness. I shot in jpg because I want the file size to be small to upload without any PP manupilations, RAW conversion etc.




I'd like to see 2 shots shot in raw and converted to JPG.
- On a tripod with a cable release
- both camera and subject on a flat plane

- 1 shot you'll sharpen (in photoshop or GIMP etc.) and one shot you won't. What PP software do you use? I use photoshop CS2

Does both camera and subject on a flat plane mean subject and camera sensor on parallel fields?

I will do that and upload soon.

tirediron
10-07-2009, 11:46 AM
Does both camera and subject on a flat plane mean subject and camera sensor on parallel fields?

I will do that and upload soon.

That's it!

Yisehaq
10-10-2009, 06:40 AM
All pics were taken according to Marko's suggestions!


I don't understand Yisehaq.

Why did you shoot these in Jpg if you ALWAYS shoot RAW?

We need to eliminate variables 1 at a time for ease. You should test the camera/lens by shooting in RAW because that's the way you normally shoot.

i think there's a strong chance this is a simple sharpening issue.

I'd like to see 2 shots shot in raw and converted to JPG.
- On a tripod with a cable release
- both camera and subject on a flat plane

- 1 shot you'll sharpen (in photoshop or GIMP etc.) and one shot you won't. What PP software do you use?

Yisehaq
10-10-2009, 06:45 AM
One more.....

tirediron
10-10-2009, 01:22 PM
Accounting for web compression etc, seems pretty good to me.

Yisehaq
10-11-2009, 03:58 AM
Thanks TI,
The effect of web compression is not that much. It's quite similar to the quality I have, before upload in RAW format.
Can I get more opinions pleaseeeeee?

AntZ
10-11-2009, 05:41 AM
Yisehaq, unless I have misread the instructions, I think your setup was not correct. You need to have the test sheet laying down. If you have the sheet parallel to the camera all of the sheet will be in or out of focus together. The idea of the sheet is to see where the focus is if it is not on the mark you focused on.

Yisehaq
10-11-2009, 06:10 AM
I think you are right and that was how I understood it at first but again I thought Marko wanted to see if the issue is of sharpening technique (that is what I thought at least!). So, I didn't that manner. I will do it as you've understood it and will upload again.

Yisehaq
10-12-2009, 07:33 AM
Another focus test. This time the focus was perpendicular to the camera's sensor. For me it seems some kind of front focus. If I am right???!!!!, what can be done to correct it? Ofcourse, other than taking it to camera shop. ;);)

Greg_Nuspel
10-12-2009, 08:02 AM
Another focus test. This time the focus was perpendicular to the camera's sensor. For me it seems some kind of front focus. If I am right???!!!!, what can be done to correct it? Ofcourse, other than taking it to camera shop. ;);)

Send it direct to Nikon, sorry I wish there was another solution but that is the only one I know of.

Marko
10-12-2009, 10:45 AM
Because there are several variables that can impede sharpness, I wanted to make sure that at least when both planes are parallel, there is sharpness after sharpenening. In the second set of shots (post 12), those shots look decent to me. To my eye it looks like a sharpening issue. (though I do notice the left and right sides do not look perfectly sharp and they should be IF everything was perfectly straight)

The next set looks fairly blurry though you never mentioned if they were sharpened. I think I'd be bringing this lens into a pro shop if I were you...

F8&Bthere
10-13-2009, 12:57 AM
Send it direct to Nikon, sorry I wish there was another solution but that is the only one I know of.

Well that may be good advice except for that I think the poster's equipment is Canon.

Seriously, there's so many factors at play that I would say that, from what I can see from all your sample images, there's nothing screaming out that there's something terribly wrong with this lens. And I think in this digital age with technology so advanced that I see photographers far more experienced than me reminding us all that we are often guilty of PPP (a new term I just fudged meaning Pixel Peeping Paranoia). Of course you can return to the mfg if it's easy enough for you, just to be sure, but after worrying in this same way about every lens I've ever bought I've learned to relax unless it's obvious. Leave the brick wall test shots and MTF resolution reference shots to the rarely satisfied perfectionists. Relax and enjoy. I say this after learning that probably 90% of forum reported sharpness problems are either real and user/situation related more than equipment related, or just a factor of unrealistic expectations- mostly the former.

Yisehaq
10-13-2009, 04:51 AM
Thank you all for you comments. Where I am, taking the lens to pros is out of question. I think I have to invest on another lens.:yell: :yell::yell:

F8&Bthere, I think that is good advice



At least it is good to learn that there was a problem on the equipment not only me;) I will blame my equipment from now on :D:D:D

Vladimir Naumoff
11-15-2009, 10:52 AM
Canon 350D has known issues for focusing. Your body needs to be calibrated most likely. The only thing is that calibration is going to cost you more money then your camera cost now. My friends tried everything and he will be buying a new camera soon. His 350 would do 8 out of 10 photos out of focus and he tried a lot of lenses because me and him like to rent and try different staff. So it wasn't a lens for sure. We found a few people on the net with the same issue and all of them got trapped with this Canon 350D.

Take that lens and put it in to different camera you will see what I am talking about.

My advise is start to save for a new body.

Vladimir Naumoff
11-15-2009, 11:04 AM
I looked at the pictures again and I have bad news for you. My body thinks it's the same thing. APO Sigma should give you much better results then this. The only way to be sure you have to test your lens with the same or hight version of Canon's body, XTi or 40D would do for sure. Their is a chance that an other 350D would have the same issue. May be they all after certain amount of shots must be calibrated I wouldn't take a risk.

Yisehaq
11-16-2009, 04:13 AM
Thanks Vladimir!
I think that is the only solution now. I spend to much time trying to concentrate on my focusing. I also try to use higher ISO everytime. But the result is baddd and even worse that I am concious about it. I just didn't have the courage to blame it on my equipment. The other day, I had a chance to test a few shots using Nikon 300 and I knew that my skills are not that bad on focusing. The pictures looked very sharp even on the display of the camera itself.
I am getting close to shooting 20,000 pictures now with the 350D. So, I guess you are right to suggest for a new tool.

Thanks a lot any suggestion on equipment would be appreciated. May be we need another forum for that.
but thanks again Vladmir.

Vladimir Naumoff
11-17-2009, 08:49 AM
You are welcome! But what is interesting that my body also likes Nikon now and he tried D300 and love it. Canon should make a note here that 350D converts people to Nikonists. Just a jock, but it is true.;)