Magnifying lens

elmerglue

I would like a bigger zoom (like up to 300mm) but can't afford that yet so someone suggested getting a magnifying lens. What type would you recommend for the D5100?

bruto

For some reason my previous post crashed, but I will add a short comment again here.

Two possibilities exist, and I doubt either one will be optimal if what you now have is the kit 18-55mm lens.

The first is a proper teleconverter that goes between camera and lens. Nikon does not make one for this, but some do exist. Vivitar makes a matched one but it's expensive. It will work but you'll get only double the focal length at the cost of two stops of lens speed. It's a great thing on long lenses, but the percentage gained is not much of a bargain on short ones. The quality varies, and good ones are not that cheap. Some made for long lenses may protrude into the barrel and physically not fit a zoom. If you go this way, shop carefully.

The other is a front-mounted magnifier. Those can be pretty cheap, but optically I think you will be sorry. You will probably do better just to crop what you have and save for a nice longer lens like the 55-300mm, which is a relative bargain for the quality.

ohyeahar

Actually, Nikon does make teleconverters, but they’re not going to help in this case. There’s one that offers 1.7x effective focal length and one that offers 2x effective focal length. On a kit lens, you still won’t have the reach of 300mm that you’re looking for and it’ll cost more than the 55-300mm lens.
They’re really designed for use on fast tele lenses. If you stick the 2x converter on your 18-55mm, that means your maximum aperture at 55mm is only f/11 with an effective focal length of just 110mm. That just wouldn’t be practical at all.

I agree with @bruto about the magnifier. Save up for a proper tele lens.

There was a recent post on The Phoblographer that may interest you.
http://www.thephoblographer.com/2014/07/18/true-cost-ultra-cheap-photography-products/

bruto

I made a mistake above on Nikon teleconverters. What Nikon does not make (for reasons never quite understood) is teleconverters for the older AF lenses. It is possible, apparently, to file off a piece on the teleconverter to allow screwdriver-focus AF lenses to mount and meter while focusing manually, but they are not officially compatible at all. AFS lenses, such as those we get without D3200 kit, are supported. I'm a bit behind the times on my research.

As ohyeahar mentions, Nikon teleconverters are breathtakingly expensive, and are really only applicable to getting very long reach on lenses that are already fast and long.

I note that on this site Moose has a review of the 55-300mm lens, with which I basically agree.

edit to add: while some aftermarket teleconverters might still work, I believe those made by Nikon are physically incompatible with the shorter zooms as glass elements will collide.