300 f/4 or 400 f/5.6

[cpickard2790]

Hi everyone. I am currently upgrading from a nikon d40 with 55-200 to a Canon 40D. (giving the d40 to my brother in law, since he has taken a great interest in photography.) I want to get a prime lens with my 40d. I do a lot of wildlife, mainly in the morning to afternoon, then again at night as the sun is going down. I mainly take a walk through a few fields, then its straight into the woods, under some briers and vines and other crawling around, then my route stops at a small swamp area, which is always full of birds. So I need a good all around lens. I am wondering how much a difference in reach is the 300 to 400? Will the f/4 to f/5.6 make that big of difference? I shoot a lot of birds, squirrels, rabbits, and deer. Kind of a wide variety. Would the 400 f/5.6 do fine in the woods and cloudy days? Even if it was just a monopod? I would really prefer to handhold as much as possible since I do a lot of crawling around. I am just worried the 300 wont bring me the reach I am hoping for, but I could be wrong.

 

[frXnz kafka]

How about the 300mm and a 1.4x TC? Then you get 300mm f/4, and 420mm f/5.6

 

[sabbath999]

There is a huge difference in the f/4 to f/5.6... more so than the extra 100mm (I have a 50-500 bigma so I shoot from time to time at all these ranges)...

I would MUCH rather have the f/4 300 and a GOOD 1.4 TC.

 

[PatrickHMS]

Don't forget that the longer lens with a smaller aperture will also have a different depth of field...

Also, the "longer" you shoot, the more difficult to hand-hold, the more you need a tripod / monopod.

 

[cpickard2790]

With a 300mm and a 1.6x crop factor and 1.4 TC ... how many feet to your object is ideal? To get a great shot. Say for a bird or squirrel? And a deer?

 

[Battou]

I use a 400mm 5.6 handheld on a full frame film body, I'm gonna tell you right now you will find it nearly impossible to shoot a 400mm 5.6 on a crop body handheld reguardless of wether, that 300 is going to be tough as well. No mater what you choose to buy, get either a monopod or a tripod for it.

 

[JustAnEngineer]

The 300mm f/4 lens does have two stops of optical image stabilization, while the 400mm f/5.6 lens has none.

 

[LWW]

I have a Nikkor 300MM F4 which I use a lot and a Sigma 400MM F5.6 which I seldom use.

Neither has VR.

The 300 is well balanced and easily hand held, the 400 much less so.

LWW