Need help on camera setings, please.

[chavez]

I have started spotting like a two moths ago with Minolta dimage A1.
I'm not a professional photographer, just civil aircrafts enthusiast.
Trying to upload to jp.net but so far, I have more rejections than acceptations , what makes me confused on how to make better pictures with my camera. Does anybody here have any spotting experience with Minolta A1 and would like to help ?

Please click on the link bellow for my pictures on jp.net:
http://www.jetphotos.net/showphotos.php?userid=8035

I take the pictures this way:
General settings: maximum resolution 2560x1920, best *jpg quality.
Landing aircrafts: manual focus on infinity (automatic seems to be too slow for landing aircrafts) the S program on 1/1000s
Standing or taxiing aircrafts: Automatic focus, S program on 1/800s

Tried to use Sharpness Hard setting.
Seems like this camera destroys picture when on maximum zoom (equiv. 200mm) or it may be caused by Sharpness Hard setting. Also I request opinion on that.

My photo editting (in PS7): horizont adjustment, cropping to cut whiteouts after rotation, levels(when shadows or highlihts are cut), curves when too dark, despectle if too grainy, automatic unsharp mask (always) and finally crop with resize to upload required resolution.

Screeners comments and advices very welcome as well, regarding general quality of my pictures

Thank you in advance.

Regards
chavez

[CheckSix]

Highest quality you can get. Shoot un Shutter Priority and use the histogram to measure the light. Settings depend mainly on the lighting, time of day etc.

[Alfred_Zeller]

Try putting your Sharpen option in normal , dont change it , do that in editing.Also make sure you´re not using digital zoom.