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10/10/2003 07:12:27 AM · #1 |
I see a big difference between my pictures out of the camera and the final version to accomodate the challenge requirements, size and compression. I have a 3.2 mp and use the highest resolution 2048X1536 Superfine.
When I open the picture in the original size I get a nice result, but after some minor corrections, mostely auto levels and auto contrast, crop little,and USM 100%, radius 2, threshold 0, the final result is pixelated
What should I do first? What should I do last? Resize first, before everything else? compress first?
Can a kind soul enlight me?
A big thank you in advance
Anabela |
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10/10/2003 07:21:34 AM · #2 |
Resize the image then apply your sharpening and stuff. That way you'll see how it's turning out at the size for DPC. Perhaps your JPEG compression is too low as the problem sounds a bit strange?
Also try fading your Auto Levels as it can sometimes be too harsh.
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10/10/2003 09:48:35 AM · #3 |
Some of the focus issue may be your depth of field. Are you familiar with F-stops? I looked at a couple of your shots and noticed that you get good sharp focus on parts of the image but not necessarily the main elements.
In this image you got a sharp shot on the tree bark but the vine is OOF (Out Of Focus). To understand DOF (Depth Of Field) you have to at least understand the direction F-stops go. Starting at f/1.4 and going up to f/22. The smaller the number, the larger the opening in the camera lens (that opening is called aperture). So f/1.4 or f/1.8 is going to be "wide open" and TONS of light will go flying into the camera when you depress the shutter button. By contrast (if you'll pardon the pun) f/11 or f/16 or f/22 are smaller apertures and so less light gets into the camera for the same amount of time. If you and I set your camera to f/4 and held it open for 30 seconds and we then set it to f/22 and held it open for 30 seconds which would let in more light? The first one because even though the shutter is held open the same amount of time, the opening for the light is MUCH larger with the f/4 setting. Now that you know that, you can just take it on faith that the less light you let in the more shallow your depth of field will be. Therefore, a camera on f/2 or f/2.8 will produce a shallow depth of field while the same camera on f/11 or f/22 will produce a photo where almost everything in the picture is in focus.
In this window lit photo you had tons of light and so the camera probably stopped down to something like 11 or 22 and gave you enough DOF (Depth Of Field) so that pretty much everything could be in focus.
I noticed a little pixelation on the stones in the wall of the building on this shot. Try setting your threshold up to 1, set the radius below 1 (say .8 or .6 or something) and then crank the junk outta the Amount. Say 300-500. Someone else posted a good tutorial on how to use USM. You should be able to find it here. The other post is here.
I think you may be getting frustrated by 2 different issues. One may be that you don't have a deep enough DOF. The solution to this is to stop down your aperture (by selecting a larger f-stop). The other is how to best use the USM. Play around with both these things and see if you aren't more satisfied with the results.
Hope this helps you,
Kev
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10/10/2003 10:06:12 AM · #4 |
Kevin - how very very helpful this mini-seminar is!
I knew about depth-of-field, but the Unsharp Mask info is priceless.
Thanks for taking the time!
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10/10/2003 01:16:03 PM · #5 |
| I think you ought to crop, at least a rough, or first draft type crop, before you resize. It seems to me that it makes no sense to downsize with parts of the image you are going to discard still present. |
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10/10/2003 02:53:10 PM · #6 |
Thank you for the kind help.
And a special one to Kevin who took the time to look at my pics and comment on them
Yes I know about DOF, but changing from SLR to simple digital has not been easy.
When I used my Nikon F3, it seems ages ago, I took quite good photos.
The vine picture, was one of the first one I took with my A70, and indeed I agree that it could be much better.
I like to get away from the AUTO and use the Aperture priority,when speed is not required, but many times I get stuck at 2,8
It was not the case with this one, I had plenty of light! Not focused on the right thing :-)
For the Nostalgia, (window lit)
Tv( Shutter Speed )
1/25
Av( Aperture Value )
4.0
Metering Mode
Evaluative
Exposure Compensation
0
ISO Speed
400
Had no tripod, hand held
I am going to study carefully the USM tutorials and try your tip also.
Thank you for your help
Have a nice week end
Anabela |
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10/10/2003 06:20:30 PM · #7 |
ISO at 400? Myself (and most I talk and heard form) try to stay at ISO 100 on their digitals. May be something to look into. Even though, it is hard sometimes to get that dark shot. ISO 200 in my cam starts showing quite a bit of noise in digital, let alone 400-800 it is almost pixellated coming out of the camera. Those are all night shots I have experimented with.
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10/10/2003 06:24:05 PM · #8 |
Originally posted by dacrazyrn:
ISO at 400? Myself (and most I talk and heard form) try to stay at ISO 100 on their digitals. May be something to look into. Even though, it is hard sometimes to get that dark shot. ISO 200 in my cam starts showing quite a bit of noise in digital, let alone 400-800 it is almost pixellated coming out of the camera. Those are all night shots I have experimented with. |
Unless you want to precisely achieve a gritty, screeny or old newspapery feel. I aim for it in some of my b and w shots. |
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