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11-15-2013, 11:31 AM   #1
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Simulating macro lenses

Hi,
Iím thinking of getting a proper macro lens (macro tubes work, but are getting annoying, and Christmas is coming). The problem is that Iíve been using my 50mm with a set of macro tubes, ad have gotten used to the field of view and working distance that they give. What I want to know is if it is possible to simulate the field of view of other macro lenses with the equipment I have?
I have the A 50mm f1.7, 2 sets of cheap macro tubes, and 2 2x multipliers.
Iím most interested in the DFA 100mm wr macro, but would look at other lenses as well, if they would be much more useful.
Is there a setup of lenses and tubes that will give me close to what the 100mm wr would give?
Thanks!

11-15-2013, 11:39 AM   #2
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If you mount the 2x teleconverter on the camera and put an extension tube between it and the 50mm you should be around 100mm and f3.5. This is what the Vivitar Macro Focusing Teleconverter does, it turns a 50mm f1.4 into a 100mm f2.8 macro that does 1:1.
11-15-2013, 04:33 PM   #3
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Thanks! I'll have a play with that then.
11-15-2013, 06:35 PM   #4
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To do what you want you need to think magnification. The 50mm lens set to infinity, with 25mm extension is at m=0.5 (1/2 life size), and m=1.0 (life size), etc. extension in mm/50mm = the magnification. When you get the field of view you like--so long as it is m=1 or less a new (true macro) should be able to do same--but verify the lens spec.

If above m=1 almost any macro (no matter what FL) will need more extension than built into the mount.
Adding one 2x teleconverter will give double magnification, and two of them will give 4 times the magnification.

Bottom line--going to a new longer focal length macro will not give greater magnification than m=1. More importantly it will not change field of view (and not the depth of field at same fstop)--but it will change the working distance and near far relationships.

11-15-2013, 06:54 PM   #5
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To amplify/answer you more:

Adding for example 25mm extension and 1 2x teleconverter will give m=1, which will,match any other macro at m=1, no matter what FL.

And for far objects (m~0) the 50mm w/o extension and 2x teleconverter is equivalent to a 100mm.

If you don't like extension tubes because you cannot get variable magnification (outside limited range) w/o adding or removing one of them, then I suggest the (used) vivitar macro teleconvereter (I kave KA, PKA were made). Excellent quality for macro w/ the 50mm f1.7 lens, and will give you as I recall about m=0.5 to 1.0 w/ it.

Another option is the vivitar 90-180mm series 1 zoom (used--I have not used but reliable sources say it is good) which gives up to m=.5 as I recall. More recent true macro zooms may be available--but make sure it is truly built to give good macro--which will not be cheap!

Finally for m less than 0.5 about, and not needing flat field, diopter add on lenses work nicely--especially convenient in the field. But for better quality (especially at larger m) you may want to use a 2 element glass (e.g., Nikon 4T).
11-15-2013, 06:59 PM   #6
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You asked about working distance and 100 mm lems. If you add the 2x to the 50mm lens, and then add extension, the working distance will be that of a 100 mm FL lens, at the same magnification (either b/c its a macro, or by again using added on extension).
11-15-2013, 07:07 PM   #7
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My Sigma 105mm goes 1:1 at 12.3 inches to the film plane - and the lens itself is 5≥/4 inches fully extended.
11-22-2013, 10:49 AM   #8
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Thanks for the in depth replies everyone! I think I'll go with the vivtar macro focusing teleconverter, and see if that gets me what I want (if nothing else, its a much cheaper option ).

11-22-2013, 11:01 AM - 1 Like   #9
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QuoteOriginally posted by bobandirus Quote
Thanks for the in depth replies everyone! I think I'll go with the vivtar macro focusing teleconverter, and see if that gets me what I want (if nothing else, its a much cheaper option ).
I like mine a lot, the one I have doesn't have contacts, but I typically use it with my M 50mm f1.4. Since you have an A lens you should look out for one with the contacts. I see them selling around $60 pretty regularly, with and without contacts.

Took this with that setup, along with my YN-560 flash, I was probably somewhere around f8. Cropped too, of course, since that is a tiny little guy.

11-22-2013, 11:09 AM   #10
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There's also a lens reversing ring. You can get pretty good results with one of those, and they're dirt cheap.
11-22-2013, 11:17 AM   #11
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(Excuse potentially dumb question)

Is this good one to go for then? I know it doesn't say Vivtar on the tube, but I'm aware that Vivtar made lenses for lots of different companies, so this might be one. Or is it just a good option, and worth going for anyway?

ebay KAX macro focusing teleconverter
11-22-2013, 11:29 AM   #12
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Other way around, Vivitar made nothing, their stuff was made by other companies who happened to make stuff for others as well. I think it was made by Kiron in this case. It looks to be the same as mine, just with the A contacts and different ribber grips. Everything I can find online says they are the same.
11-22-2013, 11:35 AM   #13
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Awesome! Thank you very much! You've been very helpful
11-22-2013, 03:28 PM   #14
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Shameless plug, but I happen to have a 100mm WR and Ring Flash for sale
02-15-2014, 10:09 AM   #15
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I have seen the cheap tubes for sale made in China on ebay. I thumbed through the B & H catalog and did not see anything in there.

Where can a better quality set of tubes be purchased other than ebay? (to be used on a manual focus lens and may or may not have the "A" setting on the aperture ring)

Thanks!

Last edited by photolady95; 02-15-2014 at 10:16 AM.
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