Next telephoto lens? What whould I get?

I'm looking to get a Canon telephoto lens... right now I have the Canon EFS 55-250mm IS, but I'm not happy with most of the results... maybe it's me or maybe the lens, but I was looking to invest in a better quality lens. I was looking at the Canon EF 70-200mm f4 L (non IS) or the Canon EF 70-300mm IS. I don't plan on going to full frame for now so either getting an EF or EFS is the same to me... Any advice on which is better? Thanks.

Before you buy a new lens, lets figure out why you arent happy with the one you have. Then we can figure out which upgrade path might be right for you. What are you concerned about with your current lens?

+1. Tell us what you don't like about 55-250?

Well, the other day I went to the zoo and I just wasn't happy with the sharpness of the photos... Here's an example of a Tiger:

HTTP response: NOT FOUND | MIME changed to 'image/gif' | Redirected to error image by FLICKR

Is F/5 wide open @ 131mm? Otherwise I'd try stopping it down a tad more.
1/128th is rather long for this focal length, although IS should be able to handle it.
For this particular example, I'd try to raise the ISO by about 2 stops, and try something similar to f/5.6 - 6.3 at this focal length.

As for your original question, the 70-200 F/4 would be sharper (much sharper), but you'd really be struggling for fast enough shutterspeeds. From what I've seen, the 70-300 isn't a whole lot sharper than the 55-250.
How about stretching the budget for a 100-400 or so?

Here's a bit of a closeup:

HTTP response: NOT FOUND | MIME changed to 'image/gif' | Redirected to error image by FLICKR

Looking at that(first) shot, I dont know that a different lens would have made that a better shot. Partially because its a lot of background and so little subject (Zoo photos are tough that way) but at f5 you only have a few feet of sharp focus and most of your shot is soft due to depth of field issues. Judging by the shadow density it wasnt that cloudy and most of your subject is in the shadow side of the image. Take a few shots where the subject fills a bit more of the frame.

shutter speed 1/128 on a moving tiger means it is probably a combo of motion blur and AF miss. You should have probably dropped to ISO 400 and did you use AI servo AF?

100% motion blur. Try shooting at ISO400 next time and a much faster shutter. you'll be way happier with the results. I got some superb shots with that lens before I bought my 70-200.

here is an example of how sharp that lens can be wide open at 250mm... This is on an XTi at ISO800 also.

IMAGE LINK: http://www.flickr.com …/40483547@N07/3​784498099/

Definitely looks like motion blur to me. A better lens won't help you there. My advice is learn to use the gear you have now, then when you know how to use it properly and realise its limitations, upgrade accordingly.

Here are some photos to show you what this lens is capable of:

IMAGE LINK: http://www.flickr.com …s/noobography/5​404521259/

IMAGE LINK: http://www.flickr.com …s/noobography/5​426607680/

100mm f/5.6 ISO400 on an XTi

IMAGE LINK: http://www.flickr.com …/40483547@N07/3​842465287/

Yeah, from reading the comments I probably should give it a few more trys with those settings and see how they come out.

are you using it on the 60d? If so, crank up that ISO!

tkbslc wrote in post #12421218
shutter speed 1/128 on a moving tiger means it is probably a combo of motion blur and AF miss. You should have probably dropped to ISO 400 and did you use AI servo AF?

I'm not sure because at first I had it on Al Focus and then switched it to Al Servo... Is Al Focus just as good for these shots?

Also, yes, I was using the lens on a Canon 60d.