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bluestringer · 06-13-2019, 01:10 PM

If I put a 2x tele converter behind my 105mm 1:1 macro lens what ratios would I be getting.

photoptimist · 06-13-2019, 01:49 PM - **2 Likes**

You'll get 2:1 when the lens is set to 1:1. It will also double the numerical value of the aperture so the image will be much darker and have more diffraction.

If you add extension tubes, adding them BETWEEN the teleconvertor and macro lens will have the biggest effect on magnification.

**marcusBMG** · 06-13-2019, 03:11 PM - **2 Likes**

Originally posted by photoptimist

also double the numerical value of the aperture

and bear in mind that at 1:1 your ?f2.8 macro lens is already has an effective f-stop close to f5.6 (see here). So add on a 2x tc and that makes near f11, before any stopping down !

jcdoss · 06-13-2019, 03:53 PM

Originally posted by photoptimist

If you add extension tubes, adding them BETWEEN the teleconvertor and macro lens will have the biggest effect on magnification.

Fascinating! I did not know that.

Thagomizer · 06-13-2019, 04:06 PM - **4 Likes**

I've used the Vivitar 2X Macro Focusing Teleconverter (V2XMFTC) on my Sigma 70mm f2.8 macro for higher magnification. It does get darker, though the actual degree of darkening was difficult for me to judge as I was shooting at night!

It combines a two times teleconverter with helicoid extension. I believe this shot might have had extension as well as the converter in play.

biz-engineer · 06-13-2019, 11:48 PM

All I can say is the HD 1.4x works well with the D-FA 100 macro WR, with no loss of sharpness stopped down a stop or two.

bluestringer · 06-14-2019, 04:34 AM

I'm not concerned about the loss of light as I use a flash for macro anyway. I always shoot manual using f16-f22 to maximize DOF. I adjust the light on my Sunpak DX-8R as needed. Thanks for the tip using the extension tube, I would not have thought about putting it in between the lenses.

bluestringer · 06-14-2019, 07:48 AM

I'm assuming the working distance stays the same with just the 2x converter attached, correct? I know it changes if I use a extension tube.

photoptimist · 06-14-2019, 10:48 AM

Originally posted by bluestringer

I'm assuming the working distance stays the same with just the 2x converter attached, correct? I know it changes if I use a extension tube.

Correct. The distance from the front of the lens to the subject does not change when adding a teleconvertor. The front lens stays put, the teleconvertor gets added to the back, and the camera goes on the back of that. Obviously, that does mean moving the tripod or yourself back by a distance equal to the thickness of the teleconvertor. You'll get 2:1 magnification with the convertor with the same working distance as 1:1 mag had without the 2X.

Or you can use the teleconvertor to get 1:1 with a longer working distance -- just set the lens to 1:2 (half of 1:1) and then add the teleconvertor.

normhead · 09-12-2019, 08:23 AM

Originally posted by marcusBMG

and bear in mind that at 1:1 your ?f2.8 macro lens is already has an effective f-stop close to f5.6 (see here). So add on a 2x tc and that makes near f11, before any stopping down !

I was skeptical about that so I did a quick check. It appears to be reasonably accurate in terms of exposure values. Checked against grey siding.

06-13-2019, 01:10 PM	#1
bluestringer Veteran Member Join Date: Nov 2011 Location: Cotton fields of South Georgia Photos: Gallery Posts: 2,748	Teleconverter on macro lens If I put a 2x tele converter behind my 105mm 1:1 macro lens what ratios would I be getting.

06-13-2019, 01:49 PM - 2 Likes	#2
photoptimist Pentaxian Join Date: Jul 2016 Photos: Albums Posts: 5,128	You'll get 2:1 when the lens is set to 1:1. It will also double the numerical value of the aperture so the image will be much darker and have more diffraction. If you add extension tubes, adding them BETWEEN the teleconvertor and macro lens will have the biggest effect on magnification. Last edited by photoptimist; 06-13-2019 at 02:38 PM. Reason: typos

06-13-2019, 04:06 PM - 4 Likes	#5
Thagomizer Pentaxian Join Date: Jun 2014 Location: London Ontario Posts: 2,068	I've used the Vivitar 2X Macro Focusing Teleconverter (V2XMFTC) on my Sigma 70mm f2.8 macro for higher magnification. It does get darker, though the actual degree of darkening was difficult for me to judge as I was shooting at night! It combines a two times teleconverter with helicoid extension. I believe this shot might have had extension as well as the converter in play. Last edited by Thagomizer; 06-13-2019 at 04:46 PM. Reason: Added information

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06-13-2019, 03:11 PM - 2 Likes	#3
marcusBMG Site Supporter Join Date: Nov 2012 Location: North Wales Photos: Gallery \| Albums Posts: 2,870	Originally posted by photoptimist also double the numerical value of the aperture and bear in mind that at 1:1 your ?f2.8 macro lens is already has an effective f-stop close to f5.6 (see here). So add on a 2x tc and that makes near f11, before any stopping down !

06-13-2019, 03:53 PM	#4
jcdoss Pentaxian Join Date: Nov 2012 Location: Ingelheim am Rhein, Germany Photos: Gallery \| Albums Posts: 6,801	Originally posted by photoptimist If you add extension tubes, adding them BETWEEN the teleconvertor and macro lens will have the biggest effect on magnification. Fascinating! I did not know that.

06-13-2019, 11:48 PM	#6
biz-engineer Pentaxian Join Date: Feb 2015 Photos: Gallery Posts: 12,249	All I can say is the HD 1.4x works well with the D-FA 100 macro WR, with no loss of sharpness stopped down a stop or two.

06-14-2019, 04:34 AM	#7
bluestringer Veteran Member Join Date: Nov 2011 Location: Cotton fields of South Georgia Photos: Gallery Posts: 2,748 Original Poster	I'm not concerned about the loss of light as I use a flash for macro anyway. I always shoot manual using f16-f22 to maximize DOF. I adjust the light on my Sunpak DX-8R as needed. Thanks for the tip using the extension tube, I would not have thought about putting it in between the lenses.

06-14-2019, 07:48 AM	#8
bluestringer Veteran Member Join Date: Nov 2011 Location: Cotton fields of South Georgia Photos: Gallery Posts: 2,748 Original Poster	I'm assuming the working distance stays the same with just the 2x converter attached, correct? I know it changes if I use a extension tube.

06-14-2019, 10:48 AM	#9
photoptimist Pentaxian Join Date: Jul 2016 Photos: Albums Posts: 5,128	Originally posted by bluestringer I'm assuming the working distance stays the same with just the 2x converter attached, correct? I know it changes if I use a extension tube. Correct. The distance from the front of the lens to the subject does not change when adding a teleconvertor. The front lens stays put, the teleconvertor gets added to the back, and the camera goes on the back of that. Obviously, that does mean moving the tripod or yourself back by a distance equal to the thickness of the teleconvertor. You'll get 2:1 magnification with the convertor with the same working distance as 1:1 mag had without the 2X. Or you can use the teleconvertor to get 1:1 with a longer working distance -- just set the lens to 1:2 (half of 1:1) and then add the teleconvertor.

09-12-2019, 08:23 AM	#10
normhead Pentaxian Join Date: Jun 2007 Location: Near Algonquin Park Photos: Gallery \| Albums Posts: 40,451	Originally posted by marcusBMG and bear in mind that at 1:1 your ?f2.8 macro lens is already has an effective f-stop close to f5.6 (see here). So add on a 2x tc and that makes near f11, before any stopping down ! I was skeptical about that so I did a quick check. It appears to be reasonably accurate in terms of exposure values. Checked against grey siding.

Macro Teleconverter on macro lens

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