stick with Canon 300mm F2.8 L IS MK II or get a 500mm F4 L IS MK I ?

I've been wondering if I've made the right move getting the Canon 300mm F2.8 L IS MK II over the 500mm F4 L IS MK I. I owned the 300 MK I for a small length of time moved to a Nikon 500mm F4 but it wasn't long and I wasn't happy with it due to Nikon systems, available cameras (D7100's small buffer put me off) and the weight of the 500mm Was a bit much, so I moved back to canon and got a the 300mm F2.8 L IS MK II. Im only using it on a 60D as it's all I could afford at the time, originally I purchased a 1D MK II but my dad now has that. The AF difference is still huge over the 60D however, much faster.

Ok thats some of the back story, now Im just wondering if I should have gone for the 500mm F4 L IS instead. I live in the UK where birds are quite skittish and most of anything interesting is quite far away. I do wonder if loosing that 100mm ( 700mm - 500mm and 1.4x / 600mm - 300mm and 2x ) makes a big difference when it comes to getting the shot, and weather the speed difference with AF of the 500mm and 1.4x is that big over the 300mm and 2x. I know on the 60D it can be quite slow with initial focus or in shady areas. I found that out recently as it was taking an age to focus on quite a close bird so I had the AF switch to full. I am looking to upgrade to a 70D soon.

I do like the flexibility of the 300mm and I do like it's weight as I don't drive though I often go places with my girlfriend or Dad who are both into wildlife photography and both drive. If I keep the 300mm there is more chances I can go out on my own. I think I know Im probably better off with the 300mm for now, and the IQ with the 2x is amazing though I still find I switch to the 1.4x for AF speed quite often which then limits me to 420mm. In that case I'd be better off with the bare 500mm. My main worries are the weight of the 500mm as I do like to hand hold, and the IS being the older 2 stop generation. I struggled to hold the Nikon 500mm and 1.4x Steady handheld, but I think I'd have to be realistic and use it on a tripod as I know I just can't do it. Anyway I'd love to hear your thoughts.

This thread may be of interest to you Ashley http://www.birdphotographers.net/for...r-lens-dilemma

Thanks for the link to the thread nick, oddly I've read that thread but maybe not in as much detail as I did this time. What gear are you using at the moment? your site suggests the 300mm Mk II and 7D? But I see exif for a shot taken with a 500mm. Did you switch to the 300mm? Whats your thoughts on it, would be great to get some more opinions.

That is correct Ashley my current setup is the 300mm II and 7D, I traded in my Sigma 500mm f4.5 for the 300mm last November, I had been using the Sigma for a few years prior to that. The Sigma was a nice lens but the lack of image stabilisation and the fact that in my opinion it didn’t take converters very well were the down sides to this lens for me.
I purchased the Canon just prior to going on a Caribbean cruise which as always with my holidays was a family holiday, therefore the fact the lens fitted nicely into my Pro Runner 300 AW bag and wasn’t too much to carry but was still of high quality was ideal. I bought this lens though knowing I would be able to also buy the Canon 600mm II in September 2013 (hopefully I will have it in the next couple of weeks).
I love using the 300mm with a 1.4x converter at a local man made reservoir where I lay flat out on the edge of the reservoir and let the birds come to me as they walk around the edge, it is a nice stalking and walk about lens, but in a lot of situations would probably not have enough reach.
It’s a difficult one Ashley, do you sacrifice the light weight and flexibility of the 300mm for the extra reach of the 500mm? Good luck with your decision.

Thanks Nick, didn't think it could have been the sigma 500mm you were using. I actually considered that lens with the move to Nikon before the Nikon 500mm came up. Im glad I didn't as I think I wouldn't be in the position I am today if I had gotten that one. In Some ways I wish I had kept my 300mm F2.8 L IS MK I and 7D as at least camera wise I would be happier and Im sure I could have created some great images with the Mk I lens but I wanted the IQ with the 2x that I just felt the Mk I lens lacked on the 7D.

I think looking around my plan is to stick with the 300mm, get a 70D and once Im happy with the camera and lens combo I can stop thinking the camera's AF is causing me problems and focus on creating better images through technique as I don't feel I've been focusing enough on that at all.

Having both the 300mm MK II and 600mm MK II would be amazing, your a lucky man! My hope is to one day sell the 300mm and get a 500mm MK II as the weight isn't as much of an issue as the MK I. I can gain back flexibility with a 300mm F4 or future zoom/prime lens when canon eventually announce some.

I had a 300f2.8 IS (not a II) and I found the IQ and AF speed with the 2X not good for birds. I got myself a 500f4 II and love it. The 500f4 II plus 1.4X is far superior to my own set up. Many folks on this forum has the 500f4 I and take incredible photos. So, IQ and AF wise, I think the 500f4 wins. Weight wise the 300f2.8 II wins. If weight is your concerns, I'd not get the 500f4. Wait until you have enough money to get the 500f4 II. Loi