I already have a lot of experience in Photoshop because I normally use it to edit my photos, but I've heard that Aperture is far better (or easier to use) than Photoshop. I started using the trial version but it's not that good. It's just like Lightroom. Is there any difference if i buy the full version? Also, does Aperture support plugins?
I'm currently making the transition from Lightroom over to Aperture. You are right in that Aperture is more like Lightroom than Photoshop. Its primary use is as a digital library for managing your photos, and videos. Much like iPhoto.
Lightroom and Aperture both have good editing functionality and both have the ability to use plugins for expanding the editing functions.
Both applications also allow non-destructive editing. Meaning you can always go back to the original image no matter what changes you do to the image within the application.
Aperture, like Lightroom, is designed with the photographer in mind. Digital assest management, photo editing, and exporting abilities for printing etc...
It's best to use either (or both) of these alongside Photoshop. I use Photoshop when it comes down to the heavy editing, or when I"m trying to do something more creative with the image outside the abilities of the other two applications.
I'm still learning Aperture so I cannot comment too much on its strengths and weaknesses vs Lightroom. Here is a post by Scott Bourne as to why he uses Aperture over Lightoom.
Hope some of what is here helps.
The Aperture trial is the full version so if you're not happy with it buying it may not make you any happier.
When you say Aperture isn't that good, just like Lightroom you imply that both Aperture and Lightroom aren't that good (compared with Photoshop) for your needs. You may have answered your own question.
Many photographers shoot RAW and Aperture and Lightroom are built for editing RAW files. You can do this with Photoshop too but the Adobe RAW converter is needed to get a similar workflow to Aperture and Lightroom.
Simply put, if you shoot RAW the deeper EXIF information isn't stripped out of your image by the jpeg compressor and a RAW image editor like Aperture or Lightroom will display that deeper EXIF information and allow you to control it after the image is taken.
For example, if you make a series of RAW images of friends in a room with incandescent light, those images will probably look a bit too warm or red. Lightroom and Aperture (and Photoshop with ACR) will allow you to quickly and easily use a pull down menu, choose "tungsten" and alter the white balance, usually perfectly on one or all of the images. Lightroom and Aperture both allow you to do things like this to batches of images with the same corrections needed. These kinds of batch processing tools speed up the processing of large groups of images.
You don't have to shoot RAW to change things after the fact in an image but the amount of control you'll have over a RAW image will be greater as it will contain more information for the RAW editor to latch on to and offer tools for.
If you routinely do heavy editing on individual images, HDR, cutouts, and use images in larger graphic design projects you'd certainly want to have Photoshop or other image editing software.
If you routinely do lighter editing on photographs, want to edit in batches, want better control of fine art printing, and want more of a photographer's workflow/process on working with images, Aperture and Lightroom are tools to consider.
And, as others have said, it's not all or nothing, you can use Photoshop on top or (or underneath) Aperture and/or Lightroom for occasional heavy editing.
As for which is better, Aperture or Lightroom, that's a personal preference having more to do with UI and tools and feelings about Apple and Adobe.
I use Lightroom even though I've had Aperture for years. I used them side by side for a while and while I prefer to use Apple products than get sucked into the Adobe world, for me, Lightroom is the better product with better image editing tools and a faster user interface on a wider variety of computers. It's noise reduction tools are so good they're worth the price alone. But, it goes much further with lens correction tools built in that correct for pincushion, barrel and lots of other distortions that many lenses (even high end lenses) make. I do a lot of architectural photography and the lens corrections are a spectacular feature for me.
And, while I'd prefer to stay within the Apple fold, Apple has a checkered history supporting and/or updating their "pro" products. People's unhappiness with what Apple has done with Final Cut Pro is an example of this.
I also have iPhoto on my computer and use it to capture my iCloud photo stream and while Apple products are better integrated into the Lion/iOS ecosystem, I still use Lightroom because it works better as an image editor for me.
Using Aperture/Lightroom require a different way of thinking to Photoshop.
Personally I use Lightroom as it is more like the traditional darkroom process. It's also quicker for getting lots of images out the door, which works well with my style of photography (motorsport), the editing functions aren't as deep, but they are pretty much the same as Adobe Camera Raw in Photoshop. Aperture is slightly different, but the same sort of style. Both Lightroom and Aperture have great image management databases which help my workflow a lot.
It is down to personal preference, although at 1/10th of the cost of Photoshop, Aperture is a bit of a bargain, if you can live without the extra editing features.