28-135mm EF vs. 55-250mm EF-S, please help me understand crop factor.

[klavender]

Sorry for the newbie question but I've searched Google and couldn't really understand this. I have a 40D with a 28-135mm EF lens. I understand this is a APS-C camera and since the lens is an EF that the effective zoom is 44-216mm. I would like to get more zoom but the EF-S telephoto is 55-250mm. 250mm doesn't seem like much more that 216mm and I'm not sure it's worth it. I've also looked at the EF 70-300mm which would be 112-480mm. It's twice as much money and would think I would want it slightly wider at the low end.

Also, if I go with the EF-S 55-250 would the STM be worth it over the standard? I want a quick focus as this will be used mainly for wildlife. How does the standard and STM compare to the USM of my current lens?

[Waddizzle]

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@RobertTheFat wrote:

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@ebiggs1 wrote:

In spite of all the relevant or irrelevant chit-chat, that is a Eastern Blue Bird.

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I thought he looked like a barn swallow. But one thing I'm not is a bird photographer, so I'll defer.

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Wow, I just looked up "eastern bluebird" and "barn swallow, and, boy, do they look alike!  But, the eastern bluebird has more of that white breast and belly than the barn swallow does.  I think Ernie's right.

All of which just makes me wonder, what is this critter?

I was thinking it was a "blue jay".  I'm no bird photographer, either.  But, it's a fun as fishing, at least to me.

[RobertTheFat]

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@Waddizzle wrote:

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@RobertTheFat wrote:

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@ebiggs1 wrote:

In spite of all the relevant or irrelevant chit-chat, that is a Eastern Blue Bird.

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I thought he looked like a barn swallow. But one thing I'm not is a bird photographer, so I'll defer.

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Wow, I just looked up "eastern bluebird" and "barn swallow, and, boy, do they look alike!  But, the eastern bluebird has more of that white breast and belly than the barn swallow does.  I think Ernie's right.

All of which just makes me wonder, what is this critter?

I was thinking it was a "blue jay".  I'm no bird photographer, either.  But, it's a fun as fishing, at least to me.

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Male bluejays usually have a fairly distinctive tuft of feathers on top of their heads, and this one doesn't. I don't think his body shape is quite right either. Conceivably it could be a female bluejay. But females of songbird species are usually dull in color, to avoid attracting the attention of predators while they're spending time in the nest. Bottom line: your guess is at least as good as mine.

[TTMartin]

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@RobertTheFat wrote:

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@Waddizzle wrote:

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@RobertTheFat wrote:

---

@ebiggs1 wrote:

In spite of all the relevant or irrelevant chit-chat, that is a Eastern Blue Bird.

---

I thought he looked like a barn swallow. But one thing I'm not is a bird photographer, so I'll defer.

---

Wow, I just looked up "eastern bluebird" and "barn swallow, and, boy, do they look alike!  But, the eastern bluebird has more of that white breast and belly than the barn swallow does.  I think Ernie's right.

All of which just makes me wonder, what is this critter?

I was thinking it was a "blue jay".  I'm no bird photographer, either.  But, it's a fun as fishing, at least to me.

---

Male bluejays usually have a fairly distinctive tuft of feathers on top of their heads, and this one doesn't. I don't think his body shape is quite right either. Conceivably it could be a female bluejay. But females of songbird species are usually dull in color, to avoid attracting the attention of predators while they're spending time in the nest. Bottom line: your guess is at least as good as mine.

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Looks like a male Blue Jay to me. I think the crest isn't real noticeable due to the position of the bird. Also having a pet Cockatiel, I can tell you it has a lot of control on if its crest is up or down.

[ebiggs1]

It's a blue jay.

[Waddizzle]

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@ebiggs1 wrote:

It's a blue jay.

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It's an EF 100-400mm f/4.5-5.6L IS II USM, set at 400mm, at a distance of, two car lengths, about 50 feet, on an overcast day looking for worms,  which it found, just before a rainstorm.   1/800 sec, f/6.3, ISO 1250

[klavender]

I noticed something strange about my refurb. 55-250mm lens I just bought. When holding the camera button halfway to focus, the lens moves slightly down and to the right of what I'm aiming at. When I release the button, it goes back to what I was aiming at.

[Waddizzle]

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@klavender wrote:

I noticed something strange about my refurb. 55-250mm lens I just bought. When holding the camera button halfway to focus, the lens moves slightly down and to the right of what I'm aiming at. When I release the button, it goes back to what I was aiming at.

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What do you mean by "the lens moves ...."?  Is it properly attached?  It should change length to focus.  But, ... ...????

[RobertTheFat]

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@klavender wrote:

I noticed something strange about my refurb. 55-250mm lens I just bought. When holding the camera button halfway to focus, the lens moves slightly down and to the right of what I'm aiming at. When I release the button, it goes back to what I was aiming at.

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Does it do the same thing with image stabilization turned off? Depending on what you mean by "slightly", one conceivable possibility is that pushing the shutter botton moved the camera enough to trigger the IS mechanism.

[klavender]

I had the camera on a tripod and zoomed all the way out, so it was stable. IS was turned on, I will try it tonight with the IS turned off. But I really need to be able to use IS. When looking through the viewfinder and shutter button pressed halfway, the focal points move slightly. When the shutter button is released, the focal points return to original position. It's something happening inside the lens. I guess I need to contact Canon and get a replacement.

[diverhank]

It's hard to tell just from your description of the lens dipping down (or image shift) but most likely it's because of the IS compensating.  IS is activated when the shutter button is half way down.

Since you put your camera on tripod, I highly recommend turning IS off.  Most Canon lenses automatically turn off IS when on tripod but there's no guarantee.  There are always a bit of noise in any electronic sensors so even on a tripod without any movement the IS mechanism will read some numbers (noise) and wrongly compensates for it, resulting in more blurred pictures.  You don't need IS if you don't shake and usually when the camera is on tripod, there is no shake.