New Lense Needed EF-S 55-155 2.8

wasn't this discussed several times already? there is little to no advantage in the ef-s design for telephoto lenses, in contrast to wide angle. a telephoto lens would me marginally smaller, at best, while wide angle lenses take a huge benefit from the ef-s system.

Making it an EF-S lens may not reduce the size, but the proposed lens should be much smaller/lighter than a 70-200/2.8 - try comparing the size/weight of the Sigma 50-150/2.8 to the 70-200/2.8.

I used to love my 50-150mm f2.8 Sigma for events on my 450D due to it's extremely low weight and smaller size...

Just sayin'

the sigma is roughly the amount smaller i'd expect it to be, given the difference in focal length. there might be a slight advantage for the ef-s even at telephoto FLs, however i am pretty sure if there was a significant margin canon would have made a fast ef-s tele already. i have no evidence tho, so i would be interested if someone could come up with a somewhat more scientific explanation.

Doesn't sound like a bad idea to me. On the other hand, the chances of Canon actually doing it... probably not likely.

DreDaze wrote in post #11608952
what are you really basing all this on?...EF-S just means that the back of the lens is set farther in so it's closer to the sensor...the reason the 70-200F4IS is bigger, and heavier is because of the constant aperture...one stop= a huge difference in weight...

the 55-250IS, and 70-300IS are just about the same size...the weight is different because of the build on the 70-300IS is beefier...but the EF-S doesn't really make it any smaller...

look at the EF-S 17-55f2.8 compared to the EF 16-35L...they weigh about the same...

For telephoto lenses, the consensus on these forums seems to be that EF-S offers no size advantage relative to EF lenses. While that may be true, a 50-150 f/2.8 would still be smaller than a 70-200 f/2.8 because it's 50mm shorter.

Tony_Stark wrote in post #11607740
Not going to lie but where did you come up with the "155" FL? The gap between 55mm and 70mm is not nearly wide enough to warrant a new lens. And why do they need to compliment an EF-S lens?

I use a Tokina 50-135mm f2.8 and you'd be surprised how big the gap between 50 and 70 is when you are shooting portraits.

Personally, I think 55 would be too long. I know it meshes well with the 17-55 progression, but 55 is 90mm equivalent. That's too long for a portrait zoom. 50 is pushing it on the 50-135mm. I'd like a true 70-200 equivalent for FF, so 44-125mm f2.8 IS.

The only problem is that you know Canon would charge $1200+ for it.

tkbslc wrote in post #11610495
I use a Tokina 50-135mm f2.8 and you'd be surprised how big the gap between 50 and 70 is when you are shooting portraits.

Not only for portraits , but as a walk around lens also .

I use the Sigma 50-150mm 2.8 . I love the range over the 70-200mms on a crop body. But I doubt Canon will ever make one . It's a shame Tokina discontinued the 50-135.

kendon wrote in post #11610399
i would be interested if someone could come up with a somewhat more scientific explanation.

Me too.

My limited understanding is that EF-S lenses can be smaller/lighter than EF lenses because an EF lens has to produce an image circle of around 50mm to cover a FF sensor, where a EF-S lens would only have to produce about a 32mm image circle to cover a 1.6x crop sensor. This is the same logic that explains why you can have a 480mm lens on a point and shoot that is only a couple of inches long.

But the way I understand it, there are other factors that come into play on relative aperture size. An f/2 lens on a point and shoot does not let in as much light as an f/2 lens on a DSLR, even though (mathematically) the point and shoot is technically an f/2.

Again, I'm no expert... but I'd love to hear from one. In my opinion, the 7D showed Canon's commitment to the 1.6x crop sensor, and I figured they would have released some higher end EF-S lenses by now. But maybe I'm totally wrong on this, which would explain why they haven't.

Yeah, you all may be right. Maybe it wouldn't make a difference if it was EF-S. I think the idea, though, is to close the gap between 55 and 70 for users of crop bodies.

A 35-135 f/2.8 does sound pretty nice. Just as others have said, it would make an excellent portrait lens but probably will never be made because it would cannibalize Canon's market for their own lenses.

I'm Not good at this stuff, but would either of these proposed lenses likely have 77mm filters? In other words, what diameter is required at the different focal length/aperture combinations?

I would go for the 44-125 or say 45-125...whatever. I like some overlap in my zooms and the lower length makes it more flexible for sports, etc with a 1.4X and 2X.

Granted there is the sigma lense, I prefer canon for the IS and better overall quality what then do it right. If we could get the same quality as the 15-85 that would be a perfect fit for the 7D.

Yoderrm wrote in post #11611024
Me too.

My limited understanding is that EF-S lenses can be smaller/lighter than EF lenses because an EF lens has to produce an image circle of around 50mm to cover a FF sensor, where a EF-S lens would only have to produce about a 32mm image circle to cover a 1.6x crop sensor. This is the same logic that explains why you can have a 480mm lens on a point and shoot that is only a couple of inches long.

the image circle is one thing, the other thing is that by design (smaller mirror) the rear element of the lens can be closer to the sensor plane on ef-s compared to FF. apparently this is a bigger issue with shorter focal lengths.

Yoderrm wrote in post #11611024
But the way I understand it, there are other factors that come into play on relative aperture size. An f/2 lens on a point and shoot does not let in as much light as an f/2 lens on a DSLR, even though (mathematically) the point and shoot is technically an f/2.

f/2 is f/2. the point is the f, which is the focal length. say you have a 50mm lens, f/2 means the aperture diameter is 25mm (50mm divided by 2). that will be the same on every lens, and it will let in exactly the same amount of light on every lens (for arguments sake let's ignore differences between good and bad glass). the important difference is that a 50mm lens is a "normal" focal length on FF, a short telephoto on aps-c crop, and close to a supertele on a p&s. for example my lumix tz5 has a 4.7-47mm zoom lens, which is the equivalent of a 28-300mm on FF or 18-200 on aps-c (numbers rounded to match real world lenses). so if you have the p&s and the dslr, both at the wide end and both at f/2, you got 4.7mm on the p&s and 28mm on the FF, or 18mm on aps-c.
to sum it up: there is no p&s with a 480mm lens. maybe there is, but then it's a bridge and far from compact (think rebel size, bit smaller maybe). my lumix has a cropfactor of 5.95 compared to FF, if you had a 480mm focal length on that it would be the equivalent of 2850mm on FF. this camera would be marketed with a 100x optical zoom... (assumed that the lens zooms out to a decent wide angle).

Yoderrm wrote in post #11611024
Again, I'm no expert... but I'd love to hear from one. In my opinion, the 7D showed Canon's commitment to the 1.6x crop sensor, and I figured they would have released some higher end EF-S lenses by now. But maybe I'm totally wrong on this, which would explain why they haven't.

looking at the 17-55, i wonder the same thing...

It looks like Sigma discontinued their 50-150mm lens also . Be nice if they brought it back out with OS on .

I'd be all over a 55-155mm f/2.8 IS.

kendon wrote in post #11611339
to sum it up: there is no p&s with a 480mm lens. maybe there is, but then it's a bridge and far from compact (think rebel size, bit smaller maybe). my lumix has a cropfactor of 5.95 compared to FF, if you had a 480mm focal length on that it would be the equivalent of 2850mm on FF. this camera would be marketed with a 100x optical zoom... (assumed that the lens zooms out to a decent wide angle).

I meant to say 35mm equivalent of 480mm, I didn't mean physically 480mm.