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04/18/2005 03:43:38 PM · #26 |
To test the lens you really want a well exposed image with a nice even histogram. If you have a flash powerful enough, it helps a lot (with birds outdoors). You could also try shooting a stuffed animal in a morning sunbeam in a manner that fills the better part of your frame. To use a bird shot for sharpness you want to be able to make out feathers, something like this.
It's probably easier to get a good position and lighting on a stuffed animal as birds aren't usually coopoerative models (at least for me!). The fur is great for bringing out sharpness, where a distant animal or subject can go dull for many reasons outside the scope of your experiment.
You will also want to shoot at different focal lengths, adjusting your position to approximate the same size subject in the frame. Many lenses differ in sharpness over their zoom range.
Tripod is a must, and either use remote shutter release or self-timer.
Finally, take those images and look at 100% crops. Should give you what you need to know regarding relative sharpness, especially if you compare to another lens in your inventory.
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04/18/2005 07:12:39 PM · #27 |
Originally posted by kyebosh:
ok it's pretty easy, just take a detailed part of the picture when it's in full resolution and crop to that section only, you'll probably want that to be a 500 x 500 give or take a bunch crop. don't resize it! Save it like that. Basically you just want a piece of the photo so that we can see what a portion of the full verion looks like before resizing.
I gotta go to class i'll be back later tonight. |
Just do not resample the picture during cropping (don't have it set to crop to a certain pixel hight/width). |
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04/18/2005 07:13:59 PM · #28 |
Originally posted by Plexxoid:
Originally posted by kyebosh:
ok it's pretty easy, just take a detailed part of the picture when it's in full resolution and crop to that section only, you'll probably want that to be a 500 x 500 give or take a bunch crop. don't resize it! Save it like that. Basically you just want a piece of the photo so that we can see what a portion of the full verion looks like before resizing.
I gotta go to class i'll be back later tonight. |
Just do not resample the picture during cropping (don't have it set to crop to a certain pixel hight/width). |
Just like it came out of the camera?
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04/18/2005 07:22:59 PM · #29 |
Your sharpness looks fine to me. Especially for shooting RAW -- your in-camera sharpness isn't going to matter (I know you said you had it cranked to the max) -- that only affects your in-camera processing and in RAW, there is none. From what I see, your sharpness seems perfectly normal.
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04/18/2005 09:25:03 PM · #30 |
I think Frederico's problem right now is understanding the 100% crop.
Within your image convertor (Photoshop?), you need to go to 100%...ie: down to the actual image size. In Photoshop it is View/Actual Pixels. Others should say something close to that. In the bottom left of the image window you will see a precentage...it should be 100%.
Set the crop tool to whatever size you would like (640px x 640px or 500px x 500px), crop an area of detail. Save As or Save for Web as another file name, somewhere. upload it here.
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04/18/2005 09:47:59 PM · #31 |
Originally posted by dacrazyrn:
I think Frederico's problem right now is understanding the 100% crop.
Within your image convertor (Photoshop?), you need to go to 100%...ie: down to the actual image size. In Photoshop it is View/Actual Pixels. Others should say something close to that. In the bottom left of the image window you will see a precentage...it should be 100%.
Set the crop tool to whatever size you would like (640px x 640px or 500px x 500px), crop an area of detail. Save As or Save for Web as another file name, somewhere. upload it here. |
I did exactly what you said and this is the result. 
Is it sharp or not? i guess it's still a little soft.
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04/18/2005 09:49:42 PM · #32 |
| I think it looks alright, not that soft, but not very sharp either. It's not the best test of sharpness doing it this way though. |
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04/18/2005 09:52:27 PM · #33 |
But i guess i have to have in mind that this lens is that great too... at least the quality so i might wanna be happy with this result... :)
Thanks guys for the help i try a newspaper test when i have the time...
Thanks a lot for your time on this...
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04/18/2005 10:05:43 PM · #34 |
Originally posted by dacrazyrn:
I think Frederico's problem right now is understanding the 100% crop.
Within your image convertor (Photoshop?), you need to go to 100%...ie: down to the actual image size. In Photoshop it is View/Actual Pixels. Others should say something close to that. In the bottom left of the image window you will see a precentage...it should be 100%.
Set the crop tool to whatever size you would like (640px x 640px or 500px x 500px), crop an area of detail. Save As or Save for Web as another file name, somewhere. upload it here. |
In PSE2, if you set it like that, it will stretch or compress whatever you crop to 500x500 or whatever you set it to, thus resampling... |
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04/18/2005 10:56:21 PM · #35 |
Originally posted by Plexxoid:
In PSE2, if you set it like that, it will stretch or compress whatever you crop to 500x500 or whatever you set it to, thus resampling... |
How? If you are only Cropping...not resizing the image, how does it resample? . I use the Crop tool. No resampling done with that.
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