telephoto

The lens itself is high quality and after examining the images, I could not find anything bad to say. I am using a Coolpix 5400. The images were sharp from corner to corner with good contrast. The fit and finish are excellent.

On the other hand, you can only use this at max zoom. If you reduce the zoom at all, the corners start to vignette. I am used to the 2X teleconverters that go between the lens and the camera body. They do not have this problem.

A couple of other complaints are that the focus is set at infinity and the internal flash is disabled if you set the camera for tele. You can over ride this by using the "auto" mode, however the lower left of your image will have a shadow from the lens barrel. I have not tried my speedlight with the tele, but I would expect this to work OK since it is much further away from the lens.

The last issue is not a big deal, but if you use the optical view finder, the lens blocks a substantial portion of the viewing area. You might be inclined to move the camera to the right to see what you are shooting.

Over all the quailty is good and I can work with its limitations, but I wish it was a 2X and could zoom without that vignetting effect.

You'd better have tripod ready when purchased this telescope. It's powerful zoom factor 420 mm(equal 35 mm camera). In order to get a good picture from this telescope you must learn how to control exposure and speed shot. It's an excellent tool for Nikon Coolpix 5700.

The item does extend the zoom range. (But, one has to purchase the adapter separately to use it at all. It's not expensive, but it should come as a package since the lens is useless without it!)
It comes with caps for both ends. However, the adapter has to come off to use the one for that end of the lens. The cap does not fit the camera end of the adapter. Either you take it apart - which leaves you with a piece capable of scratching other things - or leave the end open. The bag provided does accomadate the two pieces and offers some protection from scratches, but not dust.

Attaching it is easy enough. But, having to do a quick change from normal to the telephoto or vica-versa is not amoung it's virtues. Of course, some of this has to do with the menues of the camera, since one has to change the lens setting too. Resign yourself to just shooting for distance, or carry a second camera to avoid missing an opportunity wihtin normal range. You KNOW how uncooperative wildlife can be!
Most focusing is done by the camera's autofocus. You can do
some general range-finding with the camea's zoom control. Then it's up to the camera. Having the menues set for the correct white balance and focus options is also important because it helps the autofocus.
In short, it does the job as long as one knows how to use all the camera's options to assist.