First third-party lens

[John_SD]

I am thinking about purchasing the Sigma 18-200mm F3.5-6.3 DC Macro HSM lens.This would be my first third-party lens purchase. It would obviously be used as a walking-around lens. If I buy it, I'll likely buy directly from Sigma. 

A couple of questions. Does anyone have this lens? If so, what has been your experience with it? I am a little concerned about the sizable range of 18-200mm, in terms of photo quality, especially at the tele end.. Yet the examples I've seen online seem very good to me. 

I'd be interested in your thoughts. 

[Waddizzle]

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@John_SD wrote:

I am thinking about purchasing the Sigma 18-200mm F3.5-6.3 DC Macro HSM lens.This would be my first third-party lens purchase. It would obviously be used as a walking-around lens. If I buy it, I'll likely buy directly from Sigma. 

A couple of questions. Does anyone have this lens? If so, what has been your experience with it? I am a little concerned about the sizable range of 18-200mm, in terms of photo quality, especially at the tele end.. Yet the examples I've seen online seem very good to me. 

I'd be interested in your thoughts. 

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I think the ratio of the longest to the shortest focal lengths is to great for IQ not to have suffered in the design of the lens.  Judging from that range, I'd say that you're trying to kill two birds with one stone.  I use three lenses to cover a similar range.

EF 16-35mm f/2.8L II USM

EF 24-105mm f/4L IS USM

EF 70-200mm f/2.8L IS II USM

I am not suggesting that you go out and buy those particular lenses.  I am saying that if you want to up your game, then a lens with a focal range of f/3.5-6.3, and a zoom ratio of 10:1, is not going to do it.  Go for fast lenses, with a zoom ratio of 4:1, or less.

I forget.  What camera body are you using?

[John_SD]

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@Waddizzle wrote:

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@John_SD wrote:

I am thinking about purchasing the Sigma 18-200mm F3.5-6.3 DC Macro HSM lens.This would be my first third-party lens purchase. It would obviously be used as a walking-around lens. If I buy it, I'll likely buy directly from Sigma. 

A couple of questions. Does anyone have this lens? If so, what has been your experience with it? I am a little concerned about the sizable range of 18-200mm, in terms of photo quality, especially at the tele end.. Yet the examples I've seen online seem very good to me. 

I'd be interested in your thoughts. 

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I think the ratio of the longest to the shortest focal lengths is to great for IQ not to have suffered in the design of the lens.  Judging from that range, I'd say that you're trying to kill two birds with one stone.  I use three lenses to cover a similar range.

EF 16-35mm f/2.8L II USM

EF 24-105mm f/4L IS USM

EF 70-200mm f/2.8L IS II USM

I am not suggesting that you go out and buy those particular lenses.  I am saying that if you want to up your game, then a lens with a focal range of f/3.5-6.3, and a zoom ratio of 10:1, is not going to do it.  Go for fast lenses, with a zoom ratio of 4:1, or less.

I forget.  What camera body are you using?

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I am using the T6. And I hear you about the 10:1 ratio. I think there might be too many compromises made in that lens. I think something closer to 24-105 might be where I need to move next.

Edit: I should note that the T6 was purchased with the intent of helping me learn about DSLR photography at a low entry-level price. In that regard, it is serving its purpose quite well. But I believe that I will soon be ready to move on to something bigger and better. Rumor has it that the 6D Mark 2 is near release. I should probably sit tight for a little while on the lenses. I may move up to full frame yet! 🙂

https://petapixel.com/2017/06/15/canon-6d-mark-ii-new-26mp-sensor-june-29-unveiling-report/

[Waddizzle]

Before you start buying high quality lenses, i suggest that you make a decision as to whether you want to buy EF mount lenses, or EF-S mount lenses.  I had bought a T5, and outgrew it within a few months.  

I knew I wanted a new camera body, but didn't know enough about the different models to choose one.  But, I did know enough about the lenses to know that EF mount worked on any camera, and EF-S did not.  I chose to only buy EF lenses because they worked on all camera bodies.  

After buying a couple of EF mount lenses, I noticed that they seemed to be better built than EF-S lenses.  Although, the EF-S 10-22mm f/3.5-4.5 is a definite exception to that observation.

I assembled my lens bag one lens at a time.  I have not seen a new EF mount lens from Canon, which was not an "L" series lens, in a couple of years.  Most EF lenses are quite older designs, most of which are outperformed by EF-S "STM" lenses.  I figured that if I wanted EF mount lenses, then they would have to be "L" lenses.

---------------------------------------------

I am certain that the T6 can produce pretty good images.  I know my T5 can produce high quality images when used with high quality lenses.

Why do you think you need a new lens?  What need is the Sigma 18-200 fulfilling?  What do you gain with the 18-200mm?

[EDIT]. I'm not asking these questions because I want to know the answers, as much as you should be asking yourself these question.

[TCampbell]

It's more difficult to achieve good optics when the glass elements have a physically larger diameter.  In other words it's possible to create high quality optics in a smaller size for less money.  But the catch is that the image circle being projected isn't big enough to cover the size of a full frame sensor.

So there's certainly a cost advantage of the EF-S lenses.  But beyond this, there are some EF-S lenses that are designed with affordability in mind.  However, there are are some lenses that are fairly impressive.

Originally the great EF-S lenses were the 17-55mm f/2.8, the 10-22mm and the 60mm macro.

But recently, Canon redesigned a few lenses and is now offering them with the "STM" focus motors.  All the EF-S lenses with "STM" motors also have redesigned optics and they're all significantly improved over their predecessors.

The zoom lenses, however, have different focal length ranges based on the sensor sizes.  For example, the EF-S 10-22mm on a Canon APS-C sensor body is actually the equivalent of the EF 16-35mm when used on a full-frame sensor body ... that is to say both lenses actually provide the same "angle of view".  

When the focal length of a lens exactly matches the diagonal measure of the imaging sensor then that lens would offer a 1.0x magnification.  For an APS-C camera that's about 27mm.  For a full-frame camera that's about 43mm.  Nobody actually makes a 27mm or 43mm lens.  So for an APS-C camera, the 28mm lens is about as close as it gets and for a full-frame camera the 50mm lens is considered the "normal" focal length (also the 40mm pancake lens is pretty close.)

If you were to use the EF 24-105mm (a lens designed for full-frame sensor cameras but will work on any Canon EOS camera) then you'll find the lens has almost no wide-angle (24mm is too close to 27mm) so it's pretty much a "normal" focal length through telephoto.  For the EF-S lenses the low end is commonly around 18mm on most general purpose zooms (although you can get wider lenses.)

Most general-purpose lenses (aka "standard zoom") offer a bit in the wide-angle direction as well as a bit in the narrow angle direction.

[RobertTheFat]

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@TCampbell wrote:

It's more difficult to achieve good optics when the glass elements have a physically larger diameter.  In other words it's possible to create high quality optics in a smaller size for less money.  But the catch is that the image circle being projected isn't big enough to cover the size of a full frame sensor.

So there's certainly a cost advantage of the EF-S lenses.  But beyond this, there are some EF-S lenses that are designed with affordability in mind.  However, there are are some lenses that are fairly impressive.

Originally the great EF-S lenses were the 17-55mm f/2.8, the 10-22mm and the 60mm macro.

But recently, Canon redesigned a few lenses and is now offering them with the "STM" focus motors.  All the EF-S lenses with "STM" motors also have redesigned optics and they're all significantly improved over their predecessors.

The zoom lenses, however, have different focal length ranges based on the sensor sizes.  For example, the EF-S 10-22mm on a Canon APS-C sensor body is actually the equivalent of the EF 16-35mm when used on a full-frame sensor body ... that is to say both lenses actually provide the same "angle of view".  

When the focal length of a lens exactly matches the diagonal measure of the imaging sensor then that lens would offer a 1.0x magnification.  For an APS-C camera that's about 27mm.  For a full-frame camera that's about 43mm.  Nobody actually makes a 27mm or 43mm lens.  So for an APS-C camera, the 28mm lens is about as close as it gets and for a full-frame camera the 50mm lens is considered the "normal" focal length (also the 40mm pancake lens is pretty close.)

If you were to use the EF 24-105mm (a lens designed for full-frame sensor cameras but will work on any Canon EOS camera) then you'll find the lens has almost no wide-angle (24mm is too close to 27mm) so it's pretty much a "normal" focal length through telephoto.  For the EF-S lenses the low end is commonly around 18mm on most general purpose zooms (although you can get wider lenses.)

Most general-purpose lenses (aka "standard zoom") offer a bit in the wide-angle direction as well as a bit in the narrow angle direction.

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One additional point worth mentioning is that an EF lens of a given focal length may actually perform better on an APS-C camera than on a full-frame camera. That's because you're only using the center of the lens's image circle, and the sharpness of any lens tends to fall off nearer the edge. So if, for example, you're willing to overlook the fact that it doesn't have much of a wide end, the 24-105 can be a very nice walking-around lens on your T6 while you're waiting to go FF. I bought that lens with my second 7D because I planned to go FF eventually. And while I didn't use it a lot before I got my 5D3, it produced excellent results when I did use it.

[Waddizzle]

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@RobertTheFat wrote:

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@TCampbell wrote:

If you were to use the EF 24-105mm (a lens designed for full-frame sensor cameras but will work on any Canon EOS camera) then you'll find the lens has almost no wide-angle (24mm is too close to 27mm) so it's pretty much a "normal" focal length through telephoto.  For the EF-S lenses the low end is commonly around 18mm on most general purpose zooms (although you can get wider lenses.)

Most general-purpose lenses (aka "standard zoom") offer a bit in the wide-angle direction as well as a bit in the narrow angle direction.

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One additional point worth mentioning is that an EF lens of a given focal length may actually perform better on an APS-C camera than on a full-frame camera. That's because you're only using the center of the lens's image circle, and the sharpness of any lens tends to fall off nearer the edge. So if, for example, you're willing to overlook the fact that it doesn't have much of a wide end, the 24-105 can be a very nice walking-around lens on your T6 while you're waiting to go FF. I bought that lens with my second 7D because I planned to go FF eventually. And while I didn't use it a lot before I got my 5D3, it produced excellent results when I did use it.

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I followed a similar route.  I had bought the EF 24-105 f/4L before I had a full frame.  I figured that I still had my T5 kit lens available for "wide angle" shots.  After using th 24-105 one time, I realized how bad the kit lens really was.  I wanted a fast, wide angle lens, which led my to buying a Rokinon 14mm T3.1 cinema lens.  

Thanks to the short hyperfocal distance of the 14mm lens, I can dial in the focus at infinity, and everything beyond a few feet is in razor sharp focus.  I do not need to adjust the focus ring.  It's perfect for outdoor shots.  It is a relatively inexpensive lens, and I waited to buy it when it was discounted.

Now, the Sigma you were looking at seems to have a number happy users.  It can probably fulfill the snapshot roll ver well.  Just be aware that because it is a third party lens, your camera cannot compensate for it, and neither can Canon's DPP software.  If you are using Lightroom, then compensating third party lenses is not an issue.

[Mr_Fusion]

 I should note that the T6 was purchased with the intent of helping me learn about DSLR photography at a low entry-level price. In that regard, it is serving its purpose quite well. But I believe that I will soon be ready to move on to something bigger and better. Rumor has it that the 6D Mark 2 is near release. I should probably sit tight for a little while on the lenses. I may move up to full frame yet! 

Good. Remember that any lens you buy today, you should be buying with an upgrade in mind. The T6 is a good camera and will take any EOS lens Canon makes. The 6D doesn't. The "S" series lenses will only fit the cropped sensor (Rebel) cameras, such as the T6. 

There is no reason to hold off on buying a better lens now with the sole exception of "can you afford it". But do buy a lens that will last. I have a couple of lenses my wife bought almost 25 years ago for her Rebel film camera. They work and are still good glass. I seldom use them but don't hesitate. (They go with my back-up camera)

[RobertTheFat]

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@Mr_Fusion wrote:

 I should note that the T6 was purchased with the intent of helping me learn about DSLR photography at a low entry-level price. In that regard, it is serving its purpose quite well. But I believe that I will soon be ready to move on to something bigger and better. Rumor has it that the 6D Mark 2 is near release. I should probably sit tight for a little while on the lenses. I may move up to full frame yet! 

Good. Remember that any lens you buy today, you should be buying with an upgrade in mind. The T6 is a good camera and will take any EOS lens Canon makes. The 6D doesn't. The "S" series lenses will only fit the cropped sensor (Rebel) cameras, such as the T6. 

There is no reason to hold off on buying a better lens now with the sole exception of "can you afford it". But do buy a lens that will last. I have a couple of lenses my wife bought almost 25 years ago for her Rebel film camera. They work and are still good glass. I seldom use them but don't hesitate. (They go with my back-up camera)

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NO!! The 7D series and the n0D series (most recently the 80D) will also accept EF-S lenses.

[Mr_Fusion]

NO!! The 7D series and the n0D series (most recently the 80D) will also accept EF-S lenses.

True, however, both are APC-C, or cropped sensors. I should have been more specific with  "(such as the Rebel)".