Will a longer exposure add detail to landscape photos? How can I make landscapes look sharper?

If anything, the longer the exposure, the less detail you will get, because it gives things more time to move. Even when you're looking at a "still" landscape scene, the tree branches may be moving a bit, water will be rippling, clouds will be slowly scudding across the sky...

A few of my all-time favorite photos are technically marred because of this. They'd be perfect, except for a bit of motion blur on the peripheral tree leaves.

I see evidence of several other problems inferred from details from your question:

• Minimum aperture - Using minimum aperture is not necessarily the best thing. The smaller the aperture, the more diffraction error you will have. (This is why you don't see lenses with ƒ/128 apertures.) Sometimes ƒ/11 is plenty to get you the DoF you want, where you want it.

  This may well be the case in your example photo. I don't see anything particularly close to the camera, so you don't need extreme depth of field. You'd want to run the numbers through a depth of field calculator — such as my ƒ/Calc Online — to be sure.

  Another feature in ƒ/Calc may be helpful here, too: its hyperfocal distance calculator. That gets you the maximium DoF at a given aperture. You might be able to get away with ƒ/11 by focusing at the hyperfocal distance instead of ƒ/16 focused at infinity, for example.

• Handheld - It should go without saying that using a tripod will give sharper shots.

• Stitching - This is an extension of the handheld point, because the more linear the movement between images taken for a panorama, the less distortion the stitching software will have to apply to line everything up again. If you get really serious about this, you will invest in a pano head.

• Kit lens - Sad to say, this may well be the biggest contributor to your problem. That lens is probably one of the least sharp lenses in your camera manufacturer's line of lenses. Going with the same manufacturer's pro-class zoom with similar zoom range will help considerably, and going with a prime instead of a zoom will help some more on top of that.

There are some other things you can do that don't stem from direct criticisms of what you've posted:

• Mirror lockup and a shutter release - Once you get that camera onto a tripod, and maybe on a pano head besides, you still have a chance at vibration from mirror slap and your hand pressing the shutter button. Locking the mirror up and using a shutter release ensure the camera body and lens are as still as you can reasonably hope for when the shutter opens.

  Some people go to even more extremes, adding sandbags to the tripod and such. I think this is probably only worthwhile when taking pictures in windy conditions, and then only when the shutter speeds get long.

• Shutter speed - Part of the problem with using small apertures is that it requires longer shutter speeds. But, let's say you've calculated that you don't actually need ƒ/22 and can get away with ƒ/11. If all that did was change your shutter speed from 1/2 second to 1/8 second, you still have enough time for motion blur.

  At that point, you want to start considering whether you can push the ISO. If not, you might consider upgrading to a body that will let you. A pro-class body can get quite good results these days at ISO 2000+, whereas a low-end body shouldn't ever be pushed past about ISO 800 if tack-sharp quality is the goal, because noise will obscure the detail you capture with all the other tips. Or, you'll blur the detail away with noise reduction software.

• Noise reduction - Just following on from the previous point, when shooting for tack-sharpness, you mustn't use noise reduction software. (Or, use it very carefully.)

  • You may have some in-camera noise reduction at the raw capture stage; turn it off in the camera settings, if it lets you.

  • The camera may do noise reduction as part of the raw-to-JPEG conversion; shoot raw instead.

  • Your image manipulation software probably has a noise reduction feature; elect not to use it when you need every last pixel.

• Better body - Once upon a time, in the film days, those of us with low-end camera bodies contented ourselves with the observation that a body was just a light-tight box, and all the important contributors to image quality were in the lens and film. Now that the body is the film, so to speak, that isn't the case any more. It is simply a fact that a Canon 5D Mk III will take sharper pictures than a Rebel XS, all else being equal. There are simply more pixels on the sensor, and they're "better" pixels on top of that.