Help me, please - DPChallenge Forums

Sigma 15mm f/2.8 EX Diagonal Fisheye for Nikon

03/09/2003 08:30:41 PM · #1

A quick question, to which i hope there is a quick answer! ;-)

Recently, I have noticed that when I take a picture with a diagonal line, it shows up as a jaggy at a lower resolution. If I "blow it up" to full size, the jaggies are gone and the picture is focused, even.

The problem? After resizing (or resampling) for a entry here, the jaggies still exist, even in the "640 x 480" (or whatever size I choose) format. It is noticeable on my Leading Lines entry, and it is really notieceable on my bridge pictures.

Oh yea, my pictures (especially trees) look oversharpened, but my sharpening in camera is set on "0," and I am not applying any in post processing.

Hep me, hep me, hep me!!!!!

edit -- I meant that the jaggies show up at a smaller picture size, not necessarily a resolution.

Message edited by author 2003-03-09 20:34:23.

muckpond

Nikon D200

03/09/2003 08:44:44 PM · #2

I don't know what software you're using, but make sure your pictures are in RGB mode when they are resized. If you're in "Indexed Color" mode, the jaggies can be bad.

Did this help?

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

03/09/2003 08:48:41 PM · #3

I'm using Paintshop Pro 7. Is there an equivalency?

GeneralE

Canon PowerShot S3 IS

03/09/2003 09:05:16 PM · #4

This is always a problem with diagonal lines...there's just not enough pixels at the lower resolution to make a smooth line.

Try this workaround:

Measure or estimate the angle of the most important diagonals. Rotate the entire image to those lines are exactly horizontal or vertical. Assuming that doesn't ruin the photo right there, perform the re-size command on the rotated image, then rotate back and crop as necessary. This may give a better result that what you get now, but I've never used PSP so no promises this time...

Canon EF 70-200mm f/2.8L USM

03/09/2003 10:16:29 PM · #5

That helped a little bit. Thanks.

It was happening to my husband's pictures as well, so we have almost decided it is a software glitch, and not a camera thing, or something at this point.

Have any other paintshop users noticed this?

kevinswope

Canon EOS-1D Mark II

03/09/2003 11:05:08 PM · #6

I use paint shop and photo shop eliments, I beleive what your seeing is a software issue. I too notice problems simillar to yours when using paint shop. I bet if you printed the image you wouldnt notice the problem hardly if at all and id bet if you opened up the same image in another program you wouldnt notice it as much.
Maybe you could open the image in your browser {paint shop does have this option} and see if you dont notice it as much.
As was said by someone else earlier, there is always some sort of pixilation with diaganal lines at some point but theye can be minimized.
I really like paint shop pro and i just downloaded the beta {for free at jasc.com} and am looking foward to testing it out.

Karmat, I just reread you problem and realized that in paint shop it is true that there is pixilization of images when the image is magnified {i mean minimized} to less then its full size, photo shop does not have this problem.
I should note that this pixilization is limmited to the monitor and limmited to paint shop. If you were to print this image or open it in a differet program or if you posted it to the web, you should not notice this pixilization.
Sorry for rambling on, good luck, Kevin