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01-11-2009, 05:07 PM   #1
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Will this lens do "macro" for me?

Sorry about my ignorance, but I recently purchased this lens used off the marketplace here on pentaxforums. I am very happy with the lens, however, I guess I don't know if it will give me close up pictures. Oh, I'm using it on a K100D.

I purchased it for banging around with me for soccer games, softball games, etc., and not for close up work.

Any info you could provide on this? Thank you.

vmax84




01-11-2009, 05:22 PM   #2
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It does say "macro" on it, but if it does give close-up images, for the life of me, I can't figure it out.

vmax84
01-11-2009, 05:28 PM   #3
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This is a close focussing zoom lens but not a true macro. You can get to 1:39 with this lens but you want to get to 1:2 or 1:1 for real macro. For that you would need a macro lens. There are lots of them out there at a range of prices.

Do you have a budget?
01-11-2009, 05:31 PM   #4
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QuoteOriginally posted by joelovotti Quote
This is a close focussing zoom lens but not a true macro. You can get to 1:39 with this lens but you want to get to 1:2 or 1:1 for real macro. For that you would need a macro lens. There are lots of them out there at a range of prices.

Do you have a budget?
Well, with the economy the way it is, I really need to stay under a couple hundred bucks.

vmax84

Or, keep saving and just have fun with the stuff I got, too!!

01-11-2009, 05:47 PM   #5
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It looks like that lens is a good starting point for macro work. As is it'll do a 1:3.9 magnification at full zoom. That's a field width of about 3.9*22mm=86mm.

You can add a good achromatic diopter lens on the front to get higher magnifications. The formula is:
New_mag=Old_mag+Focal_Length*Diopter(1+old_mag)

for your case, that's:
New_mag=old_mag + 0.3*diopter(1+1/3.9)=0.26+0.377*diopter

So a relatively weak close-up diopter lens like a nikon 6T* = +2.9 diopter will give you a magnification of up to about 1.35:1 for a field width of 22mm/1.35=16.3mm

That sounds like a good setup to me. Magnifications higher than 1.35 or so will be hard to handle.

Your lens has a real advantage of having its maximum magnification at its longest focal length. That gives you good working distance which, beside making lighting easy, keeps you away from stinging insects.

Dave

*A 6T currently on eBay has a bid of about $9usd now. It'll maybe go for $25-35?

Last edited by newarts; 01-11-2009 at 07:28 PM.
01-11-2009, 06:41 PM   #6
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An alternative to a true macro lens, use an extension tubes with a normal 50 mm lens. There are quite a lot available in ebay at low cost or in the market pl. Another option, use a reverse ring adapter for a normal 50 mm lens- low cost on adapter. You have the feature of 1:1 mag but depth of field is shallow and shorter focusing distance.

Theere are some articles written here on this subject already.

marcus
01-11-2009, 10:00 PM   #7
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QuoteOriginally posted by vmax84 Quote
It does say "macro" on it, but if it does give close-up images, for the life of me, I can't figure it out.
Set it to the longest zoom setting (300mm), set the focus as close as it goes (1.5m, according to the box), and you'll get magnification of 1:3.9 - which is to say, not as quite good as the kit lens (18-55) set to its longest zoom setting and shortest focal distance.

Stick a Raynox 150 in front of it and it will focus a *lot* closer snd thus take much more closeup pictures. But it will probably vignette.
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