Full Frame vs Crop Lens?

[RooDog]

I saw a video about lenses. It was talking about putting a Pro Lens on a Crop Sensor camera, hoping to get sharper photo. But that it was not as good as a Standard Lens. I did not think a Full Frame or Crop Sensor would need different lenses. I’ve never seen a lens say it was for one or the other.? Does it really matter? Thanks

[ScottyP]

In the Canon lens world, there are two mounts. 

EF lenses fit both full frame cameras and crop cameras. 

EF-s lenses only fit crop cameras. 

There are plenty of EF lenses that are not as good as some EF-s lenses.

The "pro" level lenses are EF lenses with an "L" in the name, and which have a red ring around the end. There would be few, if any, current  "L" lenses that are bested by any EF-s lenses. 

[Waddizzle]

---

@RooDog wrote:

I saw a video about lenses. It was talking about putting a Pro Lens on a Crop Sensor camera, hoping to get sharper photo. But that it was not as good as a Standard Lens. I did not think a Full Frame or Crop Sensor would need different lenses. I’ve never seen a lens say it was for one or the other.? Does it really matter? Thanks

---

It sounds like you may have missed something that was said in the video. 

Canon EOS DSLR camera bodies use one of two different image sensor sizes: Full-Frame and APS-C, with the APS-C sensor sometimes being referred to as a "crop sensor."   Canon EOS lens model numbers start with either "EF" or "EF-S", which help to distinguish how the lens is made. 

The Full Frame camera bodies only use "EF" lenses that project a larger image circle, which can cover an entire full frame sensor.  "EF-S" lenses typically use smaller lens elements that project a smaller image circle, which is just large enough to cover the smaller APS-C image sensors. 

The APS-C camera bodies use a bayonnet mount that can accomodate either EF or EF-S lenses.  The Full Frame bodies use a bayonett mount that can only accomodate lenses Canon lenses that have model numbers that begin with "EF".  EF-S lenses are designed expressly for use with Canon's less costly consumer oriented EOS DSLR camera bodies that use APS-C sensors.  

Canon's "L Series" of professional grade lenses are all EF mount lenses.  But, not all EF lenses are "L Series" lenses.  Because of the physically smaller lens elements that are typically found in EF-S lenses, EF-S lenses typically can cost less than their EF lens equivalents. 

[TTMartin]

---

@RooDog wrote:

I saw a video about lenses. It was talking about putting a Pro Lens on a Crop Sensor camera, hoping to get sharper photo. But that it was not as good as a Standard Lens. I did not think a Full Frame or Crop Sensor would need different lenses. I’ve never seen a lens say it was for one or the other.? Does it really matter? Thanks

---

The video was right on the money. Modern STM EF-S lenses will give you better performance than older 'Pro' full frame lenses. A lot of money you pay for Pro full frame lenses is to give them edge to edge performance that you literally never see when using it on a crop sensor camera. If your choice is between an STM EF-S lens and full frame lens for you APS-C camera with very few exceptions you are better off with the STM EF-S lens. 

[ebiggs1]

In addition to what was said above, the correct definition is ef-s lens are designed to have a shorter focal plane.  The "S" stands for 'short focusl'.

This is why the image circle is smaller. Not because the sensor is smaller.  Since the image circle is smaller it allows the sensor to be smaller.  There is a lot of confusion about crop sensor camera.  The biggest is, they are full frame.  They are just a smaller full frame.  There are some advantages and there are some disadvantages.

The theory is if you use 'ef' lenses on a camera designed to use 'ef-s' lenses, you utilize only the center of the image circle.  That is supposed to be the sharpest part.  In my experience it may or may not be true.  My general gut feeling is, it is probably true most of the time any way.

If one compares any current "L" lens to any ef-s lens, the L will be better.  Matter of fact any 'ef' lens will be better and any 'ef-s' lens.  At the very least they will be equal.  I have not found otherwise in any case.

[TTMartin]

The classic example of this mistake is the person who gets rid of their EF-S 18-55 IS STM kit lens and goes out and buys an EF 17-40 f/4L. In addition to losing image stabilization and zoom range, they give up sharpness. The money spent on the EF 17-40 f/4L would have been much better spent on the EF-S 17-55 f/2.8 IS.

There are a number of places you can go to confirm this. You can use the MTFs that Canon provides. The Digital Picture website lets you compare test chart photos from different lenses on the same camera. Or DXO as shown below gives a quantitative number and puts it in a nice colored chart. Regardless the source of the information they show the same thing, replacing a EF-S 18-55 IS STM kit lens with a EF 17-40 f/4L for better image quality is a waste of money.

[RooDog]

I have a Canon 70D Crop. My only lens is my EF 100-300 Ultrasonic. I bougt it in 1992 or 1994? It's OK, but not real sharp and very slow focus. I need a bigger zoom like this because I'm in a chair and can't use my hands. So if alone, I can't change lenses and being in a wheelchair, often can't get as close to what I'm shooting. I can't aford a super nice lens, but would these lenses be any better (Canon EF 75-300 f4-5.6 III)? 

Canon EF-S 55-250, F4-5.6 IS STM 

Or what ?-300 lower end zoom would be the best ?

Thanks so much, Greg

[ebiggs1]

Greg,

What would be the budget or price point you can handle?  The best choice might be either (a Tamron or Sigma) of the 150-600mm super zooms.

Barring that, any current zoom is going to be better than your current lens.

IMHO, one of the worse ways to compare a lens is the MTF chart.  They are so misleading and confusing to the average person as to be useless.  Again IMHO, one of the less reliable sources is DXO. 

Check out one of the super zoom 150-600mils.  If they are out of the price range, Sigma made a, pretty nice, now discontinued lens, the Sigma 150-500mm.  It will be a used only option unless you get real lucky and find a NOS (new-old-stock).

[TTMartin]

---

@RooDog wrote:

I have a Canon 70D Crop. My only lens is my EF 100-300 Ultrasonic. I bougt it in 1992 or 1994? It's OK, but not real sharp and very slow focus. I need a bigger zoom like this because I'm in a chair and can't use my hands. So if alone, I can't change lenses and being in a wheelchair, often can't get as close to what I'm shooting. I can't aford a super nice lens, but would these lenses be any better (Canon EF 75-300 f4-5.6 III)? 

Canon EF-S 55-250, F4-5.6 IS STM 

Or what ?-300 lower end zoom would be the best ?

Thanks so much, Greg

---

I have the EF-S 55-250 IS STM and I would recommend it. What you lose in focal length you gain in sharpness and ability to crop. It is a lighter weight lens, and if you're mobility impaired I suspect that would be a big plus for you. It has image stabilization which your older 100-300 lens lacked. Don't let the low price of the EF-S 55-250 IS STM scare you away from it. It performs like a lens that costs 5 times as much.

[RooDog]

Thanks so much. Weight and size can be an issue, mostly when trying to follow something moving. Very hard. I have  movable, multi joint, arm, that holds the camera. Then the camera is on a bird swing like gimbal. So I can turn 360, and rock up-down.

I was looking at this today, Canon EF-S 55-250, F4-5.6 IS STM. And its $299. But the same lens, minus the STM, is $149. The on-line chat guy said its exactly the same, but not as quite or smooth. Would be great to save that much it true. Think so?

I've always loved photography, but film was just to costly for how few turned out. A DSLR really helped that. I just started about 6 weeks ago, mostly doing double exposures, in camera. You can see some of my stuff at:

https://www.viewbug.com/member/MyDogRoo

Thanks so much, Greg