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10-25-2011, 06:35 AM   #31
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QuoteOriginally posted by dinneenp Quote
thanks again. Call me slow but just one or two more questions (honestly).
1.
So I could use this alone with my Tamron 17-50mm f2.8 lens- great.
Yes

QuoteQuote:
So if I used this at 17mm then wouldn't the magnification ratio be greater than one ( 36/17)? But I imagine the problem is that I'd have to be virtually on top of the item?
yes - the nominal maximum would be 36/17 = 2.1X and working distance would be about

Working.distance ~ F(1+1/m) ~ 25mm.

QuoteQuote:
2. the light/aperture is halved so I'd have f5.6?
Actually the aperture will be what is set on the lens multiplied by (1+m)

QuoteQuote:
It looks like potentially a very cheap solution. If not I think I'd just buy a manual focus macro lens (thanks for the links so far).

Oh, why can't I be rich so I could just buy an autofocus macro lens that'd be great for kids portraits and macro photography (and a wide angle lens and a K-5...)

Cheers,
pa
Do not forget the option of an achromatic +5 close up lens on your 200mm. - it would give you a working distance of around 200mm. An advantage is that it is easy to carry & quick to mount. The drawback is the edges of the image will be soft but that almost never matters for macro. Perhaps someone will tell us if the Raynox 150 vignettes on the 200:2.8. For sure the 67 or77mm marumi will not.

Or a Cosina 100 3.5 for about the same $$.


Last edited by newarts; 10-25-2011 at 06:55 AM.
10-25-2011, 06:37 AM   #32
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I have two macro lenses that I think complete each other pretty well.

For shallow DOF/casual macro I use Tokina AT-X 90mm f2.5 (bokina). It's got a lot of sharpness and bokeh to die for, but is only 1:2 without extension (wich I don't have). Both M and A versions exist. This is the same as Vivitar Series 1 90mm f2.5 Macro. On film it's an awesome portrait lens.

For deep DOF/more serious macro, I use Elicar 90mm f2.5. This lens is not as sharp wide open, nor has it got as pretty bokeh, but it's sharpness sweet-spot is around f11-f16, making it ideal to use with a ring flash. This is the same as the Vivitar (not Series 1) 90mm f2.5 Macro. Both M and A versions exist of this lens as well.

As extension, I've recently aquired a Vivitar Macro Focusing Teleconverter. It's both a 2x teleconverter geared towards close focus performance, as well as a modifiable extension tube. Both M and A versions exist.

Don't shoot spiders with that setup, it will give you nightmares X-(

Last edited by topace; 10-25-2011 at 06:50 AM. Reason: consistent naming
10-25-2011, 07:21 AM   #33
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thanks again for the replies, I think I have it understood now (almost). After all the research, browsing, looking the hype gets built up pretty big.

My gut feeling is not to go for ring flash option; the easier the solution appeals to me. If I'm out (with my Slingshot AW200) and see a macro opporunity I want to be able to set up and shoot eaisly and quickly.
10-25-2011, 08:19 AM   #34
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hmmmm.... Cosina 100mm F3.5 MC Macro comes in autofocus. It's 1:2 but if I get a convorter thingy it'd be 1:1 and autofocus. Sounds very tempting, I don't mind that "its build quality might provoke open mocking laughter"

10-25-2011, 08:30 AM   #35
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The Cosina 100mm (and variations) usually include the 1:1 adapter. This is a +4-5d (or thereabouts) add-on lens going to the filter thread. The quality of this is pretty good; I'd suspect it is an achromat (2 element job). However, with this on the working distance is pretty much fixed so AF is not terribly useful with the add-on (but then it would not be so with macro in general).
10-25-2011, 09:52 AM   #36
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QuoteOriginally posted by dinneenp Quote
1. So I could use this alone with my Tamron 17-50mm f2.8 lens- great.
So if I used this at 17mm then wouldn't the magnification ratio be greater than one ( 36/17)? But I imagine the problem is that I'd have to be virtually on top of the item?
We figure magnification as M= (TE-FL)/FL where TE is Total Extension and FL is Focal Length. Total Extension is the tube length plus the amount the lens is already extended by its body. The thickness of the 2X TC's I've encountered is 25mm. So with your zoom at infinity focus at 17mm on a deglassed 25mm-thick TC or tube, TE= 25+17, and M= 25/17= ~1.5x.

Subject distance will be 17mm from the lens' optical center. Yes, you'll be right atop the subject! I've put a 10mm tube behind a Zenitar 16/2.8, but any thicker tube is just nutz. That's why we don't have 1:2 or stronger macro lenses shorter than about 35mm.

I just put my 18-55 on a 25mm TC and at 17mm I literally can't get the lens close enough to a target -- I bump right into it. With the lens at 25mm, I can focus with the front of the lens 1cm from the subject. It's just too close.

QuoteQuote:
2. the light/aperture is halved so I'd have f5.6?
We calculate light loss as M+1 stops. EA= NA*(M+1) where EA is effective aperture, NA is nominal aperture, and M is magnification. So with your zoom at 17/2.8 on the 25mm-thick tube/TC, M= 1.5, and EA= 2.8*2.5= f/7. Magnification eats light, unless you use a Raynox or other +dioptre adapter.

QuoteQuote:
It looks like potentially a very cheap solution. If not I think I'd just buy a manual focus macro lens (thanks for the links so far).
Extension depends on how close you want to work, and at what magnification. Remember that you can't focus closer than a non-reversed lens' focal length, and the greatest magnification will be there. So if you go the route of getting 2 or 3 deglassed 2X TCs, you can use your zoom in its 30-70mm range -- a fairly cheap option for macro there. If you had a longer zoom, some +dioptre adapters would be the budget solution.

QuoteQuote:
Oh, why can't I be rich so I could just buy an autofocus macro lens that'd be great for kids portraits and macro photography (and a wide angle lens and a K-5...)
Hay, it's only money. Rob a minimart or do some ID theft or go into politics. There's always a way.
10-26-2011, 05:47 AM   #37
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QuoteOriginally posted by jolepp Quote
The Cosina 100mm (and variations) usually include the 1:1 adapter. This is a +4-5d (or thereabouts) add-on lens going to the filter thread. The quality of this is pretty good; I'd suspect it is an achromat (2 element job). However, with this on the working distance is pretty much fixed so AF is not terribly useful with the add-on (but then it would not be so with macro in general).
With this lens and the adapter am I losing light?
If yes then I'd go with something else. If not then it looks like I've found my lens.
10-26-2011, 06:04 AM   #38
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QuoteOriginally posted by dinneenp Quote
With this lens and the adapter am I losing light?
If yes then I'd go with something else. If not then it looks like I've found my lens.
You will not be losing light with the adapter but the working distance will decrease to about 100mm - not a big problem usually.

I think it is a toss-up between the Cosina & adapter or your sport lens with adapter.

10-26-2011, 06:34 AM   #39
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QuoteOriginally posted by newarts Quote
You will not be losing light with the adapter but the working distance will decrease to about 100mm - not a big problem usually.

I think it is a toss-up between the Cosina & adapter or your sport lens with adapter.
Thanks for the reply.
An adapter with my sports lens would be a cheaper solution but as the lens is big and heavy I haven't really considered it before.
Especially as I don't always have it in my Lowepro Slingshot bag, whereas carrying the Cosina & adapter wouldn't be much extra weight.

I guess as long as I'm not shooting living life things the distance shouldn't be an issue...
10-26-2011, 06:44 AM   #40
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QuoteOriginally posted by dinneenp Quote
Thanks for the reply.
An adapter with my sports lens would be a cheaper solution but as the lens is big and heavy I haven't really considered it before.
Especially as I don't always have it in my Lowepro Slingshot bag, whereas carrying the Cosina & adapter wouldn't be much extra weight.

I guess as long as I'm not shooting living life things the distance shouldn't be an issue...
I agree. The 70-200 is too big & heavy to be lugging around all the time. Besides a 77mm adapter will cost as much as the Cosina. I mentioned it for completeness sake.
10-26-2011, 03:13 PM   #41
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Thanks for all the replies. I've places an ad looking for the Cosina AF and adapter.
I think the AF would be handy for portraits too (I have two young kids).
10-26-2011, 03:21 PM   #42
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As I understand, your parameters are 1) not to expensive, 2) not too heavy|bulky, and 3) not too close. If you want to use flash, especially ringflash, an A-type or AF lens is fairly easy to use; but without flash, any good macro setup will do. And you don't require ultimate glass for commercial publication. Does that sum it up?

OK, the quick-cheap-and-dirty way is to get a short A-type zoom (used) like the A28-70 or any non-DA 28-80mm, something in that range, and a mount-reversal ring. Leave the ring on front of the lens and you've got a standard A-type or AF zoom. Flip it around and you've got a sharp manual-only macro-zoom that focuses from under two inches out to infinity. Get a cheap PK macro tube set to use as a lens hood when reversed. All that for under US$30 probably.

Or for simplicity and no light loss, get a set of +1+2+4 closeup adapters for your short zoom; price should be under US$25. The +1 will give you a working distance of 20-25cm / 8-10in. Stack all three for a working distance of 15cm / 6in. The further you zoom in, the greater the magnification, which won't approach 1:1. For better image quality (and a bit more money, maybe US$65) get a Raynox DCR-250, for a working distance of about 13cm / 5in.

Or... I've already suggested a stack of deglassed A-type TCs for your short zoom, but they eat light, as does any extension. Others have suggested dedicated macro lenses in the 100mm range, but they cost a bit more, especially AF. Advantage: Easy to use. Those are about all your options, within your parameters. Good luck!
10-26-2011, 03:48 PM   #43
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Hi,
Thanks for the detailed reply.
As I understand, your parameters are 1) not to expensive, 2) not too heavy|bulky, and 3) not too close. If you want to use flash, especially ringflash, an A-type or AF lens is fairly easy to use; but without flash, any good macro setup will do. And you don't require ultimate glass for commercial publication. Does that sum it up?
Pretty much spot on.
Heavy I don't mind but not a MASSIVE heavey lens (like my Sigma 70-200 f2.8).
My gut feeling is not to use flash; the simpler, quicker the better.
not for commercial, just to venture into the big world of macro

I flirted with the idea of the Raynox but couldn't work out what magnification I'd get. It did kind of seem like a good option as I just snap it on. Maybe I just got fed up of checking out yet another option and discarded it (a bit hasty maybe). Quick review: may cause vignetting, can I shoot in shutter or aperture modes?

For the +1+2+4 closeup adapters what kind of magnification would I get and do you mean having three adapters on top of each other?
10-26-2011, 05:43 PM   #44
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In the CHEAP MACRO article I have the table and simple formula for figuring working distance and magnification with any +dioptre adapters. Such adapters can be stacked (screwed together) and their strength summed, so +1+2+4 stacked are +7dpt. Working distance is entirely controlled by the dioptre strength:

+1 >> 20-38" (500-950mm)
+2 >> 13-20" (330-500mm)
+3 >> 10-13" (250-330mm)
+4 >> 8--10" (205-250mm)
+5 >> 6.5-8" (165-205mm)
+6 >> 6-6.5" (153-165mm)
+8 >> 5" ---- (127mm)
+10 > 4" ---- (102mm)

Magnification is given by M= F*D/1000 where F is focal length of the host lens and and D is the dioptre strength. So a simple +4dpt screwed onto a lens at 70mm has M= 70*4/1000= 0.28x or about 1:3.5. The +8dpt Raynox DCR-250 gives 70*8/1000= 0.56x or more than 1:2 magnification. The Raynox DCR-150 is +4.8dpt. Longer focal lengths plus more dioptres give more magnification.

A closeup (+dioptre) set is the cheapest way to work close with automatic lenses. Just remember that stacking glass in front of a lens drops the IQ a bit. But punch-up the contrast and saturation in PP, and nobody will know.

Last edited by RioRico; 10-26-2011 at 05:57 PM.
10-27-2011, 02:49 AM - 1 Like   #45
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dinneeep pm'd me with this, but I'll reply here because the answer is long and may be useful to others (and may garner some comments).

QuoteOriginally posted by dinneenp:
Hi,
Thanks for all the help. I'm pming you instead of adding to my already very long thread.

I might try the closeup adapter route with my sports lens (around the house, garden etc) and if I think macro is for me then sell them and buy a proper macro lens.

So my last questions-
1. what are closeup adapters called properly (so I can search for them)
2. where can I buy them?
3. do they sit on top of my lens front, if so I'd need very wide ones for my sports lens
4. any brands to look for/avoid?

thanks again,
Pa.
Doh, I forgot that your sport zoom might have a wide objective. Yes, they screw onto the front. What is your lens' front diameter? Closeup lenses / adapters / filters (those are the usual names used) get expensive larger sizes. Raynox provides a clip-on universal adapter that fits lenses 52-67mm. Which leads to this:

Because of how a meniscus focuses light, a much smaller adapter can be used on a large-diameter lens. The Raynox adapters have a 43mm thread yet are usable on 67mm-wide lenses. I just hand-held a +1dpt 55mm adapter on a 67mm-wide zoom (60-300 @60mm) and see no vignetting. Now I put the same in front of a 77mm-wide UWA (10-24 @24mm) and again, no vignetting. But it has a small objective.

Based on the Raynox numbers, I'll guess that an adapter will work without vignetting on a lens with a thread up to ~1.6x the adapter's. To test that guess, let's see, 55x1.6= 88. I just held the same 55mm-wide meniscus in front of my 86mm-wide long zoom (170-500 @170mm, with a WIDE objective!), and... no vignetting!

So if your sport lens is up to 77mm across, a 52mm adapter set with a step-down ring should work. For a lens up to 86mm wide, use a 55mm set.

Where to get cheap meniscus closeup adapters / filters / lenses: All mine came from eBay, mostly used, mostly branded Vivitar, mostly real cheap, in 49-52-55mm threads, all in the US$5-12 range. I think I spent US$22 (new, shipped) on a 62mm set labeled Pixco. (If I'd done the above tests first, I could have saved my money!) The others were. I'm not sure the brand name is important. Just remember to use a basic hood and otherwise avoid flare. Have fun!
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