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01-14-2009, 06:07 PM   #1
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what shutter speed do you use with macro filters?

don't tell me to buy a macro lens lol because right now i'm broke and it's not on my priority list, so until i can gather the funds i thought of getting a macro filter to play around with. at 250mm with a +10 filter, how do you come up with a shutter speed for that? does the +10 mean 10x, so it'd have to be a 2500 shutter to keep it sharp? :S

01-14-2009, 06:29 PM   #2
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QuoteOriginally posted by impete82 Quote
don't tell me to buy a macro lens lol because right now i'm broke and it's not on my priority list, so until i can gather the funds i thought of getting a macro filter to play around with. at 250mm with a +10 filter, how do you come up with a shutter speed for that? does the +10 mean 10x, so it'd have to be a 2500 shutter to keep it sharp? :S
The minimum magnification you'll get with a diopter lens is:
Magnification=Focal_length_meters*Diopter.

So with a +10 diopter lens you'd get a minimum of 2.5X on your 250mm lens.

There's no way you'll be able to hand hold any closeup with a higher magnification than about 1/2 so I'd recommend a good achromatic close-up lens about +2 diopters.

Maybe a Sigma Achromatic Close-up (+1.6 diopter) or a Minolta +1 (+2 diopter, inexpensive if you can find one.)

Usually, you'll want to have a large F-stop to get some depth of field.

There's a sigma on ebay for about $30USD NEW GENUINE SIGMA ACHROMATIC 52mm MACRO CLOSE UP LENS - eBay (item 220344662682 end time Feb-13-09 03:45:29 PST)
01-14-2009, 07:07 PM   #3
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Sorry for the OT : Is that listing from the famously BAD photo store in NY ? If so I would check Reselleratings and stay away from them !
01-14-2009, 07:28 PM   #4
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QuoteOriginally posted by dantuyhoa Quote
Sorry for the OT : Is that listing from the famously BAD photo store in NY ? If so I would check Reselleratings and stay away from them !
An alternative is a genuine minolta +1 - current bid $2.99usd. Worth ten times that.
MINOLTA CLOSE UP LENS NO. 1 FOR SR 52N. - eBay (item 270329223769 end time Jan-18-09 18:08:16 PST)
I'm not sure what thread size this is..

Also a 52mm No.1 (+2) and a no.2 (+3.8) at Ritz camera for $35USD total! I think this is a bargain.
http://www.ritzcam.com/catalog/index.php?category_id=670


Last edited by newarts; 01-14-2009 at 07:37 PM.
01-15-2009, 03:29 PM   #5
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QuoteOriginally posted by impete82 Quote
i thought of getting a macro filter to play around with. at 250mm with a +10 filter, how do you come up with a shutter speed for that? does the +10 mean 10x, so it'd have to be a 2500 shutter to keep it sharp? :S
No. Closeup filters don't change the focal length of a lens at all - they only change the distance at which you can focus. If you put a closeup lens on your lens, the view doesn't change at all, except that now you can magically focus closer than you could before. The "+10" number has nothing to do with any calculations you'd need to be concerned with; all you need know is that bigger numbers allow you to focus closer, and hence provide the possibility of greater magnification. That is, the greater magnification comes from getting closer to the subject, not from increasing the magnifying power of the lens itself.

On the other hand, the closer you get, the harder it is to handhold. If you really want sharp, use a tripod. Especially since the DOF is so shallow at those macro distances - you may need to stop down to f/16 or more to get an entire bug's eye in focus, for example. So you will indeed be dealing with relatively slow shutter speeds - but because you are very close and because you are stepping down, not because the focal length has changed.

BTW, the lenses sold a "+10" etc are generally pretty low quality. For practically no more money than that, you can get a Raynox 150 or 250 that is *much* higher quality. The 250 allows closer focusing and hence more magnification than the 150, but it actually *forces* you to focus that closely - the 150 can be better because it allows you a few more inches breathing room.
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