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09-15-2015, 11:38 AM   #31
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QuoteOriginally posted by kentster Quote
IS there such a critter for extension tubes that allow control of the Aperture? A couple of the lens I am looking at do not have an aperture ring
SFAIK The KENKO tubes do transmit aperture info electronically, at least my old set does. BTW: I had cause to run a series of tests of extension tubes versus Raynox and other achromatic close-up filters on several of the same lenses (70mm f2.4; 180mm Voigtlander; 200mm SMCA; old Tamron 28-105 zoom). The filters gave better IQ in every comparison. In fact, some combinations of Raynox + SFL lens were indistinguishable from devoted macro lenses. Considering their compact size, convenience, excellent IQ and bargain price (~$103 for both 1.5X and 2.5X), I now recommend the Raynox to anyone starting macro, especially if they have a decent SFL lens at least 50mm long.

09-15-2015, 12:22 PM   #32
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Cool... I have the Raynox 250 already. Would that give me closer tot he 1:2 ratio ?
09-15-2015, 01:31 PM   #33
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QuoteOriginally posted by kentster Quote
Cool... I have the Raynox 250 already. Would that give me closer tot he 1:2 ratio ?

1:2 = 1/2 life size, probably the 2.5X will be give a higher magnification. The 1.5X Raynox might give 1:2 on a short FL lens (the longer the lens on which a Raynox is mounted, the higher the magnification). For 1:2, if going with a filter, you might need a Canon 250D or 500D achromatic close-up lens, depending on the FL you're using to reach 1:2. These work best on longer FL lenses, best in the range of 100~200mm. The "250" = the focus distance is reduced to 250mm (1.4 meter) when the lens is set at infinity, and as you might guess "500" = focus distance set @ 500mm (1/2 meter) when the lens is set at infinity. Note that, these focus distances apply NO MATTER THE FOCAL LENGTH OF THE LENS, which is why longer FL = higher magnification. The Raynox 1.5X and 2.5X focus distances are 8 inches and 5 inches, respectively, with any lens set to infinity. The Canon close-up filters are available in a variety of thread sizes starting at 58mm. Discontinued Nikon achromatic close-up filters, are designated 3T, 4T (both 52mm threads), 5T and 6T (both 62mm threads). And if you don't know the rule: 1000 divided by the diopter value of a close-up filter = focus distance in mm with lens @ infinity (or divide 40 by diopter = focus distance in inches, approximately). the 1.5X and 2.5X designations used by Raynox are not diopter values.

Last edited by WPRESTO; 09-15-2015 at 01:37 PM.
09-15-2015, 02:39 PM   #34
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i get all this ratio stuff mixed up.... The macro lens i'm looking at is 1:1...so a macro with 1:1 + Raynox could be 2:1 or more? Do you prefer Raynox or the screw on close up filters?

09-15-2015, 03:18 PM   #35
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QuoteOriginally posted by kentster Quote
i get all this ratio stuff mixed up.... The macro lens i'm looking at is 1:1...so a macro with 1:1 + Raynox could be 2:1 or more? Do you prefer Raynox or the screw on close up filters?
Attached to a macro lens that was focused to its nearest point, commonly @ 1:1 ratio, the Raynox would increase the magnification considerably, but I'm not sure how much. Which close-up filter I prefer depends on which lens I'm using and what magnification I'm seeking. For example, the 55-300 Pentax works quite well with a Canon 500D, but IMHO not with either Raynox. I also have a very large Canon 500D (77mm thread) that can be used on either the 60-250mm or the 300 f4. Both the 70mm f2.4 and the Voigtlander 180mm f4 work very well with Raynox, especially the 1.5X, although for mounting on these lenses, because they have 49mm filter threads and the Raynox snap-on adapter only goes down to 52mm, I had to purchase a step down ring which as I recall (don't take my word) was 49mm to 37mm.

BTW: To get very high magnification, mount a Raynox on a long SFL lens. The old 200f4 works very well. OR using the same 200 f4, use a double male-filter-thread adapter (sometimes called a "lens stacking ring') to reverse mount either a short mount bellows lens (the 100mm Pentax, either original preset or later auto-aperture version) or a high quality enlarging lens (a step-up adapter ring will be needed here). The rule is: magnification = FL of lens attached to camera divided by FL of reversed lens. So the bellows lens on the 200mm = 2X natural size. A 50mm enlarging lens reversed on a 200mm would give you 4X natural size.
10-09-2015, 12:37 PM   #36
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i've been sorting through macro options trying to find the best balance. tried out a bunch of lens/extension tube combinations.... using the kenko 68mm (12+20+36) kit with aperture contacts. best magnification is with my dfa 100mm macro... compared against da*200, da*300, da*55, and a reversed 50mm 2.0, and a reversed 28mm. with a reversed 28mm the magnification is crazy.... but not worth it to lose auto aperture, and if you want to get closer than 100mm with 62mm of extension tubes, then add the raynox.. adding extension tubes to the 200 and 300 does bring closer focusing(at a greater distance than the 100mm, which is a plus), but not 1:1. close enough for medium sized frogs or large dragonflies, but not close enough for beetles or crickets or flies.

unless pentax makes a 180 or 200mm 1:1 macro in the future (that i can afford), than the best choice for me is to use the 100mm 1:1, a set of auto aperture extension tubes, and the raynox 250. i tried the canon fd 200mm 1:1 macro with a fotodiox K mount adapter (took glass out... was HORRIBLE with glass in it) but the lens was not nearly as sharp at the dfa 100mm, and had ca, even when stopped down. nikon makes a great 200mm 1:1, and canon makes a crazy 5:1 macro... sigh.

also just bought a 70mm spiratone bellows macro... gets to around 2.4:1 max magnification... and pretty sharp at f16... but i wouldn't use it seriously.... fun for $20 on ebay.

---------- Post added 10-09-15 at 03:40 PM ----------

also, this guy seems pretty awesome. pentax user, very helpful
10-09-2015, 01:12 PM   #37
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Again, because of their bargain price and ease of getting to high magnification, the Raynox Macro Explorers are a real bargain.Track down the Raynox thread here on PF to see the quality of images than can be obtained. Keep in mind, the lens to which the Raynox is attached also makes a difference, with SFLs generally being better than zooms as the base lens.

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