imagemeister Loc: mid east Florida

In your case, at the moment, you should upgrade your GLASS. I recommend the Sigma 17-70 and the latest Canon 55-250 or 70-300 nano for you.

Retired fat guy with a camera Loc: Colorado

Glass. You stated you have around a $1,000 budget. In my area, on Craigslist, I found a 24-105 L for $400. I also bought a 70-200 f/4 L for another $400. Both are in perfect condition.
You will see a difference imedataley.
Later, if you feel your skills have surpassed your camera, you will still have pro glass.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

This is a perfect use of the DXO Mark rating system. You choose a body, then match it up with a lens. Since you have an 18 mp sensor, you'll be able to see how any lens tested with this body will do. There is a sharpness graph and a perceptual megapixel rating. The P-MP rates the overally sharpness against a theoretically "perfect" lens, which in this case would be 18 P-MP. So a perfect lens will provide sharpness that would leverage all 18 mp on the sensor.

A Canon 18-55 has a rating of 13 P-MP, which is actually pretty good. The sensor/lens combo is providing sharpness similar to a 13mp camera.
The Canon 75-300 (cheaper version) shows 8 P-MP - which is not great.

Just for grins and giggles I looked at the 300mm F2.8 IS USM and it returned a P-MP of 17 which is close to perfect. But it costs $6000.

And just to show you price isn't everything - I looked at the Canon EF 600mm F/4L IS II USM, which did about as well as the 18-55 at 14 P-MP

DXO Mark is a little hard to comprehend, especially if you misuse it to compare bodies to one another. One common mistake is to take the P-MP rating as a "reduction" in camera resolution, which it definitely is not. What it tells you is how a camera/lens combo would perform to another "perfect" lens on a lower resolution body. In this case a rating of 13 P-MP only means that the combo will return performance equivalent to a perfect lens on a 13 mp sensor.

If a lens that is considered quite sharp based on MTF charts shows a poor P-MP rating, you need to look at the camera format and pixel count. Often the lens surpasses the camera's resolution. In some cases, like the category of 28-300 lenses from Sigma, Canon, Nikon and others, the lens' resolution is insufficient and will retunr poor P-MP scores. Those types of lenses may score better on crop cameras than on full frame cameras, btw.

So, since your 18-55 seems to be ok, what's left would be to address a medium telephoto zoom.

one possibility would be the Sigma 50-150 which shows a P-MP of 15.
Tamron SP 70-200mm F/2.8 Di VC USD has a P-MP of 15.

There are other lenses that show 11-12 P-MP that might be worth considering.

I would dismiss any lens under 10 P-MP.

This is the DXO page for your camera - T5i (700D).

https://www.dxomark.com/Cameras/Canon/EOS-700D---Lenses-tested

burkphoto Loc: High Point, NC

So true! Good tools just make the job easier or extend the range of options. They do not make our photos. We do.

jon S

Glass@ 1000.

Rave

Your T5i is really a pretty nice camera. Your lenses aren't anything to bragg about (I have them too) and I upgraded glass. My suggestion would be to consider a Canon EF 24-105 L lens. A used one would definitley be within your reach. It's an awesome lens and on a crop frame camera the effective focal length is about 38-168. If you decide to go full frame Later on all you'll need is a body. First and foremost however, I suggest you get acquainted with Lightroom or Photoshop. Most of the amateurs that I'm learning from make good pictures look great with just a little bit of processing.

fyimo244 Loc: Arkansas

I would concur that a full frame body is not feasible and that your body will do the job. I would get better lens with your money as that would be an upgrade to your system. The Canon EF 75-100mm lens are not a very good lens no matter what version you have. My Niece has the same body as you and the same lens. I bought her an older Canon EF 100-300mm f4.5-5.6 USM for less than $100 on EBay and it's a much better lens than the 75-100mm. For you landscape pictures you might want to buy the 24mm f2.8 STM (Pancake) prime lens.

Bazbo Loc: Lisboa, Portugal

Glass.

Hbuk66 Loc: Oswego, NY

The T5i was rated as a best buy on CR for dslr... so I would say GLASS

imagemeister Loc: mid east Florida

Lens selection is not just about DXO or MTF numbers either ! ......Zoom range, maximum f-stop size, price, size/weight and more will/should also enter the decision.

dsmeltz Loc: Philadelphia

I really thinks this OP needs to stop, take a breath and figure out what the real issue is. If there is real dissatisfaction with the pictures being produced, what is causing this dissatisfaction? Is focus not fast enough? Is resolution lacking? Is ISO being forced up beyond reasonable limits for the camera? Just what is wrong with the photos from the current equipment? Until we know that, it is very hard to give really useful advice.

mas24 Loc: Southern CA

A NASCAR driver may drive your everyday automobile a lot better than you. However, if you drive the custom car developed for him, you won't do so well, because it is he, not you, who has the experience in those fast vehicles on the track. It takes years to develop those driving skills. Same with cameras, you don't start with a Canon 1DX Mark 2 or a Nikon D5. Learn your camera, then upgrade to better glass. Some photographers are still using vintage manual focus glass over 40 years old.

dsmeltz Loc: Philadelphia

Every once in a while I will switch to manual focus and not look at the images until I get home just so I can remember how awesome photographer's skills had to be before auto focus and instant review.

speters Loc: Grangeville/Idaho

Around a thousand bucks, is just not going to get you top-glass!!

rehess Loc: South Bend, Indiana, USA

It's not going to purchase top anything!!