Close-up thread lenses How To

[magkelly]

I have this set now:

http://www.amazon.com/HOYA-Filter-Close-Up-thread-lenses/dp/B0009SY8GU/ref=sr_1_2?s=electronics&ie=UTF8&qid=1284455793&sr=1-2

I get that they are for macro work, but I'm not too certain of how they work and I can't seem to pull up anything relative on Google. Any particular lens you're supposed to use them with? Do you use one at a time, stack them, both?

They look like your basic magnifying glass to me, but I figure there has to be a bit more to it that this, otherwise why would you bother with these versus say a good macro zoom?

I've never actually seen a set before so if this is a dumb question I apologize before hand. My digital has macro but I'm wondering if this is better/worse? Could be used with both film and digital SLRs?

Thanks!

[Scheimpflug]

I'll let someone else chime in with more specifics, but a few quick answers:

* The reason to buy a dedicated macro lens is that the macro lens was all designed together as one piece. The generic add-on lenses are not optimized for any particular lens, plus you are introducing one more piece of glass, so the quality will not be as good as a dedicated macro lens.

* Feel free to stack them, and feel free to use them on any lens they fit. The quality will vary (for reasons above)... so it is sort of one of those "try it and see what happens" sort of deals.

* Another option is to use extension tubes, which go between the lens and the camera. The tubes do not have any optics (so they don't degrade the image quality), and give a bit different results than close-up filters.

* Don't be afraid to experiment, and I hope I haven't discouraged you in any way. I've seen some stunning results with close-up lenses, so I wish you the best of luck.

[wilson.c]

I've played around with the screw on lenses when I was a kid and did not have much money to buy a macro lens. You are right, they are magnifying lenses of different degrees to add to the front of your lens. It basically depends on what you want to use it for, if it's for something quick and dirty and you don't want to invest in a macro setup, it would be great, but you just have to be aware of the quality issues of adding glass in front of your lens as Scheimpflug said. I was doing some reproduction work and the corners always were out not very sharp, but if it was for macro shots, this could be a nice effect.

Macro extension rings are a better option, but you need to change rings if you need more magnification. With the advances in design and manufacturing today, there are some 'variable' extension tubes that extend and retract with a twist of a ring, for a reasonable price. I usually use these for adapting lenses without focusing helicoids, but have heard they are as good as their fixed length counterparts, but with you can easily vary the length.

For the long term, a fixed macro lens is the way to go. They are optimized for close focusing distances and you don't have to fiddle around and find out that you missed the shot.

Hope this helps out.

[RioRico]

As mentioned, such +dioptre meniscus lenses are a quick-and-dirty way to shrink your working distance. They are not corrected for aberrations, as are Raynox adapters and the like, but that effect can be exploited if you wish. A +1 dioptre on a not-real-fast short tele, like the 55/5.6 end of a kit lens, can dramatically narrow the depth-of-field for portraits etc.

You'll want a lens hood on single or stacked +dioptres to improve glare and contrast. I always keep a set of these at hand when I'm noodling around in the field. I just don't expect pristine results. Yes, they work on both film and digital. I used such on my Oly Pen-FT SLR back in the mid-1970's.

For better (and simple) closeups, a corrected adapter like a Raynox DCR-150 or -250 gives excellent (but not perfect) results. These are usually around US$60. A 'macro' lens is even simpler but usually costlier. I was lucky to buy a Macro-Takumar 50/4 and Vivitar-Komine 90/2.8 (both 1:1) for low prices but I use them less than I do enlarger lenses on bellows. A system of bellows, tubes, mount-reversal rings, and enlarger lenses, gives great bang-for-the-buck.

[Nikos]

Canon's 250D (for normal) and 500D (for tele lenses) are very good.
They are double element lenses, and correct many of the glaring defects of the single element alternatives in the market.

An ideal solution to increase the magnification of a lens from, say, 0.25X to 0.35X while retaining good quality.

Example photo
(Canon EOS 20D, 50mm lens + 250D, crop)


I have also tried close-up "filters" by B+W, which were a disappointment.
They also were considerably cheaper.

Of course a macro lens is a better and more expensive solution.
But you can skip carrying a dedicated macro lens by carrying one of these.
Especially if you want to shoot close-ups and not true macro.

[visualopsins]

Read recently in the "The Pentax Way" by Herbert Keppler:

"Generally speaking a +1 lens focuses from 20" to 38"; a +2 from 13" to 20"; a +3 from 10" to 13"; a +4 from 8" to 10"; a +5 from 6.5" to 8"; a +6 from 6" to 6.5"; a +8 at 5" and a +10 at 4". The focusing distances are not dependent on focal length. No matter what lens you use on your camera, subject distance with the same close-up lenses remain the same. Naturally, the area covered varies with the focal length of the lens and the image size will be greater with the lens of longer focal length."

Thus the close-up attachment lens diopter selects the working distance, while the focal length of the lens the close-up lens is attached onto determines magnification.

[visualopsins]

More: Rick Oleson's pdf "What's a Diopter?