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Posted By: TER-OR, 07-02-2015, 06:56 AM

Does anyone have direct experience with the Sigma 180mm macro lenses? They've sold at KEH for reasonable prices used.

Alternately, the new 1.4x teleconverter can add some distance, and should be pretty nice on a 100mm.

I'm just curious, as these could both be more difficult in the field, negating the reach.
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07-02-2015, 07:08 AM   #2
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I have the 180mm f3.5 macro and have used it for years. Before that I had a Tamron 90mm 2.5 manual focus macro that was supersharp. I got the 180 both for its reach and its AF. Many folks prefer MF to AF for macro, and it can have its advantages, but I wanted both options. The 180 is helpful when you are dealing with more skittish insects and don't have to be right on top of them to get a shot. Also, the extra distance allows for more lighting options. It is heavy, if that is what you mean by "difficult in the field"....
07-02-2015, 08:27 AM   #3
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More about "difficult in the field" is about thinner DOF from longer FL. If the lens behaves itself while stopped down a lot, then OK. The 100mm Pentax macros behave themselves very well stopped down even to f19, though usually I'm lower to keep my shutter speed higher.

Though of course weight is never NOT an issue.
07-02-2015, 08:32 AM   #4
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QuoteOriginally posted by TER-OR Quote
Does anyone have direct experience with the Sigma 180mm macro lenses? They've sold at KEH for reasonable prices used.
You'll find it nearly impossible to find one in Pentax mount -- they come up very very seldom. (And they never made the 180/2.8 in Pentax mount, only earlier f/3.5)

07-02-2015, 08:52 AM   #5
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QuoteOriginally posted by TER-OR Quote
More about "difficult in the field" is about thinner DOF from longer FL.
This is a point still not clear to me. Often I read that at macro magnification DOF depends almost exclusively (i.e. the focal length contribution is negligible) on the magnification ratio. What am I missing here?
07-02-2015, 09:06 AM   #6
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QuoteOriginally posted by Daertu Quote
This is a point still not clear to me. Often I read that at macro magnification DOF depends almost exclusively (i.e. the focal length contribution is negligible) on the magnification ratio. What am I missing here?
Yeah, that's right, at a given magnification and aperture, DOF will be the same. But with a longer lens you can be farther away to get that same magnification, so the advantage of the longer lens is greater working distance from subject (which becomes a disadvantage when you want a wider shot), but everything else remains the same if you are keeping the magnification ratio the same. So the 180mm is only "more difficult in the field" if you want those wider shots often (because you'd have to back up more), but if you are always finding yourself too close to the subject, then it gain you that working distance...
07-02-2015, 09:20 AM - 1 Like   #7
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The 180mm Sigma macro is tack sharp and fairly easy to use in the field. I prefer using this lens over my Tamron 90 because of the longer working distance. If you can find one, they are worth the price. ............................Jim
07-02-2015, 09:34 AM   #8
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So it might actually be easier to get a good DOF with a longer macro, if you can get more magnification at the same distance? It seems a little counter-intuitive to me. I could use more stand-off distance in some points, and in others would enjoy less heavy cropping. This might be worth investigating.

Thanks for the feedback, guys.

07-02-2015, 09:40 AM   #9
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QuoteOriginally posted by TER-OR Quote
So it might actually be easier to get a good DOF with a longer macro, if you can get more magnification at the same distance? It seems a little counter-intuitive to me. I could use more stand-off distance in some points, and in others would enjoy less heavy cropping. This might be worth investigating.

Thanks for the feedback, guys.
If you're all the way at 1:1 (putting aside extension tubes to get you even more magnification), you of course MUST back up -- the minimum focusing distance will be farther with the 180mm. Basically, if you are using a shorter macro and you think "I wish I could be farther away and get the same shot", then the longer lens will help with that. Or if you shooting at less than 1:1 (and your lens is capable of getting there) but you can't get closer just because it is too damn close, it will also help. If you are already shooting at 1:1 and everything is great, then it won't really get you anything -- it just means you'll have to back up. (At the macro level, anyway. It of course be easier to shoot birds, etc with it as it can be used as a normal telephoto also, and will even work well with a teleconverter.)
07-02-2015, 07:59 PM   #10
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how sharp and fun is the 180?

Took some shots with the 180 and a recently purchased Pentax ring flash. Was concerned beforehand because the 180 has a 72mm filter size, whereas the largest adapter ring on the ring flash is 67mm, forcing me to use a step-down ring. Would there be serious cutoff of the image? In any case, for your purposes, they show off the lens well. See the images below, of a desert rose (Adenium) bud and then cropped to show the point of focus on the tip of the bud (about what you would see at 100% enlargement of the original shot).
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07-23-2015, 11:12 PM   #11
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I've had a 2 copies of the 180mm... the 1st one I sold it in Jan 2014.... I did not regret it but rather missed it... Last winter I found another EX++ copy on ebay from Japan at a reasonable price, and jumped on it... I am rediscovering this lens now this summer ...


But yes, this lens is quite heavy and noisy in the field... I think it renders better colors without a flash.


Here are a couple shots from the 1st copy



Sphinx colibri / Hummingbird clearwing [Hemaris thsybe]
by Sylvain Cote, sur Flickr



Hosta sp. (Abiqua Blue Crinkles)
by Sylvain Cote, sur Flickr



IMGP9484.jpg
by Sylvain Cote, sur Flickr



IMGP9474.jpg
by Sylvain Cote, sur Flickr



Pteridophytes au Jadins de Métis
by Sylvain Cote, sur Flickr



IMGP8671.jpg
by Sylvain Cote, sur Flickr





Ancolie / Granny's Bonnet [Aquilegia sp.]
by Sylvain Cote, sur Flickr



Abeille cotonnière / European wool carder bee [Anthidium manicatum]
by Sylvain Cote, sur Flickr



Vanesse du chardon / Painted Lady [Vanessa cardui]
by Sylvain Cote, sur Flickr
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