I own a Nikon 7100. It was bought in a kit bundle from a store. The price was right at the time. In that kit, the lenses were an 18-55mm zoom lens and an 55-300mm zoom lens. I shoot a lot of wildlife pictures and at the longest zoom, it's not long enough for my liking. I'm wondering if a lens extender would bring it out to 400/500mm focal lenght or should I save money to buy the equivalent focal lenght? Both of my lenses are VR lenses. I know that with an extender it won't be as sharp as a fixed lens. Any comments are welcome.

I just bought the Sony A6300 and want to purchase a telephoto lens for upcoming trips to Alaska and Africa.

Am looking at the Sony 70-200 and the Sony 70-300 (not yet released) but am having trouble deciding between them. Both are full-frame lenses and the differences seem to be:

70-200 G OSS – f4.0-22 $1400 new
70-300 G OSS - f4.5-29 $1200 new

Both are same weight; 70-300 smaller in size. Am wondering why the new lens would be cheaper. Any thoughts on what else I should look for or how to decide?

I've bodyguarded 12 African Safari (220 days in the bush with 0 casualties to clients or their staff) but the magic of Africa lures me back! Botswana is the 2nd safest country in Africa after Namibia but Capetown has some safe areas and unsafe areas. Walking around there with a camera bag is NOT a good idea just like there are safe and unsafe parts of San Francisco or any other US city so I would suggest a small, unobtrusive point and shoot for there and to stick with her group. I agree with the other posters about NOT changing lenses in the field and to get a second OMD body. A "bean bag" is very useful for wrist or elbow support when shooting from a vehicle with lots of other photographers moving around. The Delta is magnificent but she really needs to be careful at night so a small strobing high intensity, 1,000+ lumen flashlight is useful. There are over 35 known poisonous species of snakes in Africa so the constant beam flashight is useful for detecting them. I raked the sand around our tent in Botswana so when we returned from safari, the staff had left the screens open. I tracked 2 snake trails going into our tent. I beamed under our beds and two cobras were using it as a honeymoon suite. I let the staff deal with them. I beamed the brush from our dining room area to our tent another night, saw 2 eye reflections, hit the strobe and the leopardess who was waiting to ambush us fled. I've also used a strobe to scare off hyenas and baboons at night. Africa is NOT Disneyland's version of wildlife. To put it in perspective, I've had 1.6 billion seconds of enjoying Africa and only 10 not so safe seconds.
Pay attention to the BEST and usually the oldest guide in your camps.
Lens hoods and good UV filters at all times will help. Sometimes polarizing filters are useful. Good lens brushes are useful since canned air may or may not be available in Capetown when she first lands.
Before she goes, "a journey of 1,000 miles begins with one step", towards her doctor for an arm and butt full of shots for her specific areas of operations.
Powdered electrolyte solutions, sun screen (applied 30 minutes before going out) microfiber, ventilated blouses/shirts, a decent brimmed and ventilated hat with a chin strap, polarizing sun glasses (I always buy inexpensive ones from Cost Co and give them as gifts to our guides who really appreaciate them) Lightweight parkas with hoods are nice for the rides in the morning and at dusk.
Keeping the photographer safe is even more important than taking photos so pay attention to your guides.
Hang on for dear life in your vehicle when animals don't obey the "rules of etiquite" about leaving people in vehicles alone, having been charged 3 times by elephants, 2 times by hippos and 2 times by lionesses, where our quick thinking guide drove away but on one escape, a leaf spring was broken and 2 tires were punctured by thorns which made for a wild ride and a need to use the bush as a bathroom facility afterwards, which is NOT a good idea so don't go far and get back to your vehicle as soon as possible.
Still, I'd go back to Africa...its that magical.

None of the off brand, after market battery grips will hold up and continue to operate properly in all ways and continue to perform properly over time.

You simply need to save up, and spend the $239.00, at B&H Photo, and buy the correct Nikon Battery grip, that is made by Nikon, for use on your camera. It is made out of magnesium, and it is very strong, and it is precision made, just as the camera itself is, and it will give you all that you expect it to provide you with, and you will never have a single problem with it, and it will last you forever. You just have to bite the bullet, and pony up the cost of it. It isn't cheap...why should you expect it to be? It is a precision designed, heavy duty, piece of equipment!