===> More Macro Questions <===

[C.S.I.]

Hello,


I want to try to resolve an issue with macro for once and for all. Alot of you have been giving me guidance (Jon...thank you) on what to do. However, alot of my questions were fragmented off of another topic posted within the forum, and I want to try to see if I can clarify a few things :oops: .
I have a Sigma 105mm 2.8 DG EX macro. It takes ok macro shots, but I want greater magnification (better than 1:1). I have been told by some that extension tubes would give me better magnification, but will sacrifice working distance from the subject. Some have told me that using a teleconverter on the 105mm would help, but I see that most TC's are not compatible with the 105mm (is the Tamron?...Canon and Sigma arent). I have been told to try to use the Canon 500D close up lens, but again, I dont think that it is compatible (or I should say that I cannot find mention of anyone using the 500D on anything but, say a 70-200 100-300 etc...no mention of use with a macro). I have tried to use the reverse lens technique with the 105mm macro with a Pentax 50mm 1.2, works good, but you need to be like less than an inch away from the subject (kind of useless for insects etc). I have heard of the Novaflex reverse adapter technique, kind of expensive though considering that the adapter is like $400, then I would have to get a good wide angle lens to use with it (as I only have the 18-55, 70-200 and 105mm macro lens'). Last I have heard of using bellows, but I dont know anything about them, except that they are also expensive.
Again, I am trying to achieve greater magnification than 1:1 with this lens, any help would be GREATLY appreciated.
Worst case scenario if there really isnt any options for me, are there any alternatives that I can do with the 105mm macro other that 1:1 applications.......seems to work good for portrait work (if your subject is fully made up, covering any flaw that the lens pics up on the subject).

Thank You in advance......sorry for the rambling.

[Scottes]

You are correct about tubes &amp; working distance.

The Canon TC is not compatible. The Sigma and Tamron should be, but I'm not positive.

For this lens you'd want the 250D, not the 500D. The 250D is made for shorter lenses, and this may explain why you didn't find info on the 105mm + 500D. You might want to search for any short macro (Tamron 90mm, Sigma 105mm, Canon 100mm) using the 250D.

Bellows are adjustable tubes, more or less. And they're more expensive than tubes. A set of 3 (12,20,36mm) Kenko tubes is about $130. Putting 68mm of tubes on a 105mm lens should get you close to 2:1 - and about an inch from the subject again!

The 105mm lens is great for anything suitable at ~100mm - except when you need fast AF. The optics are great, the AF is slow.

[Cadwell]

The Canon TC is not compatible. The Sigma and Tamron should be, but I'm not positive.

If the Canon TC isn't compatible, neither is the Sigma EX one. They have exactly the same set of lens restrictions.

[EXA1a]

To get a specific answer, could you exactly tell us
1. what kind of objects you will mainly shoot (bugs, seeds, bacteria?)
2. what's your experience with 1:1 macros, how do you handle the real shallow DOF?
3. have you thought about lighting? (ambient light, ring flash,...?) It will become a real challenge with greater than 1:1 magnification!

[C.S.I.]

To get a specific answer, could you exactly tell us
1. what kind of objects you will mainly shoot (bugs, seeds, bacteria?)
2. what's your experience with 1:1 macros, how do you handle the real shallow DOF?
3. have you thought about lighting? (ambient light, ring flash,...?) It will become a real challenge with greater than 1:1 magnification!


Hi EXA1....

1.) Bugs, flowers, insects.
2.) Im absolutely new to macro......1 month experience....no problem with DOF.
3.) I try to do everything with bright ambient light, if possible. I will be purchasing a Sigma 500DG Super (I cant afford the good macro flashes at this time and I need a flash anyway for other applications so....)and I will try out a Bogen Manfrotto macro flash bracket to compensate for the lens http://www.bhphotovideo.com/bnh/controller/home?O=NavBar&amp;A=search&amp;Q=&amp;ci=653

Thank you

[Jon]

Using a reversed lens is the same as using a close-up lens. It alters the optics of the combined system to give you effectively a shorter focal length lens. The 50 mm lens is effectively a +20 close-up lens; the 500D is a +2. That means (look back to the example I worked out on the other thread - IIRC the 500D on the 105 would have changed the effective fl to about 75 mm) a shorter working distance at any given magnification. If you want to maximize the working distance, I'd really recommend the teleconverter route. Using a 2x tele on the 105 at 1:1 would give you 2:1 magnification at the same working distance as the 105 at 1:1 without the TC. Adding extension tubes between the lens and TC would get you in closer, while reducing the working distance. You want the extension tubes before the TC since that way they're acting on your 105. If you put them behind the TC, they're extending a 210 mm lens, so will have less effect.

The 105 macro can also be used for anything you'd use any other 105 mm. lens for. It just focusses closer than most.