Extension tubes
Apr 4, 2015 17:04:13 #
brian43053
Loc: Buffalo, NY
I've become fascinated with macro photography lately and was doing some experimenting with a set of extension tubes I received as a Christmas gift. I use them on my Sony A99 full frame camera and was pleasantly surprised to discover that the auto-focus still works when I use them on my Tamron 90mm prime lens.This is also a 1:1 macro lens. These extension tubes were by no means expensive and it didn't matter which order I lined the extension tubes up on my camera. The focus point ws the same on all 3 pics (12 o'clock) but on the pic with all 3 tubes the center of the flower is out of focus. The tubes are made by Neewer. Check 'em out.
1.) 36 mm extension tube
(Download)
2.) 36mm + 20mm extension tubes
(Download)
3.) 36mm + 20mm + 13mm tubes
(Download)
Apr 4, 2015 17:16:58 #
looks as though everything is working as intended, you just ran out of DOF on that flower.
Apr 4, 2015 18:18:38 #
brian43053
Loc: Buffalo, NY
oldtigger wrote:
The more extension tubes you use the narrower your DOF is. That's why in the last pic the center of the flower is not in focus.looks as though everything is working as intended, you just ran out of DOF on that flower.
Apr 4, 2015 19:15:16 #
brian43053 wrote:
That's a given I think all of the old timers & true macro buffs understand. If you decrease your aperture to say f/16 and get your lens tangent to the subject plane, you just might get a bit of the center as well. Hope you stick around, nice captures.The more extension tubes you use the narrower your DOF is. That's why in the last pic the center of the flower is not in focus.
Apr 4, 2015 20:25:25 #
brian43053
Loc: Buffalo, NY
I shot this in aperture mode, but i have no control over the aperture. I tried it at f/2.8 & f/32. All it did was shorten or lengthen my shutter speed. There was no difference in my depth of field no matter where i set my aperture.
Apr 5, 2015 00:15:00 #
We are familiar with the Tamron 90mm macro lens. It is excellent for 1:1 mag at Minimum Focusing Distance.
It works quite well with tubes as well.
The majority of macro-photographers shoot straight Manual camera settings. Some also Manual focus; and others rely on A-F.
What is your illumination source? That will dictate your manual settings, and you will see different DoFs at different apertures.
I strongly recommend that you read ALL of the threads listed here: http://www.uglyhedgehog.com/t-36372-1.html
It works quite well with tubes as well.
The majority of macro-photographers shoot straight Manual camera settings. Some also Manual focus; and others rely on A-F.
What is your illumination source? That will dictate your manual settings, and you will see different DoFs at different apertures.
I strongly recommend that you read ALL of the threads listed here: http://www.uglyhedgehog.com/t-36372-1.html
Apr 5, 2015 00:26:31 #
Exif info of all three images:
Camera Model: Sony SLT-A99V
Lens: ----
Image Date: 2015-04-04
Focal Length: 90mm
Aperture: /10
Exposure Time: 0.333 s (1/3-sec)
ISO equiv: 800
Exposure Bias: none
Metering Mode: Matrix
Exposure: aperture priority (semi-auto)
White Balance: Auto
Flash Fired: No
Camera Model: Sony SLT-A99V
Lens: ----
Image Date: 2015-04-04
Focal Length: 90mm
Aperture: /10
Exposure Time: 0.333 s (1/3-sec)
ISO equiv: 800
Exposure Bias: none
Metering Mode: Matrix
Exposure: aperture priority (semi-auto)
White Balance: Auto
Flash Fired: No
Apr 5, 2015 05:32:44 #
brian43053
Loc: Buffalo, NY
Nikonian72 wrote:
most times i use manual focus when doing macro but this was just an experiment to see if auto focus would work.The majority of macro-photographers shoot straight Manual camera settings. Some also Manual focus; and others rely on A-F.
Apr 5, 2015 10:18:41 #
I love my extention tubes on my Sony A77M2. One of my favorite setups is the 13mm extention tube on the 50mm at f16. As stated above the smaller aperture will help extend the in-focus area of the image.
Apr 5, 2015 10:54:57 #
brian43053 wrote:
If your camera were set at aperture priority AND you made adjustments which shortened or lengthened the shutter duration by changing your aperture, then you must have been shooting at different apertures. Otherwise, you would have noticed a dramatic change in exposure. I shot this in aperture mode, but i have no control over the aperture. I tried it at f/2.8 & f/32. All it did was shorten or lengthen my shutter speed. There was no difference in my depth of field no matter where i set my aperture.
Differences in DOF using extension tubes + a macro lens set at 1:1 will be minute. However, you can't trick science here: a change in aperture does impact DOF. It MAY BE that the increase in diffraction as you stopped down rendered the change in DOF less detectable. (Diffraction is a loss of sharpness & should not be confused with DOF).
But what is the size of this flower? The ones I've photographed would fill the frame @ 1:4 so they were maybe 2-1/2" in diameter. I have a few stacks if you are interested. I also did a "panorama close-up" stack.
Apr 5, 2015 13:35:34 #
brian43053
Loc: Buffalo, NY
LoneRangeFinder wrote:
I would be very interested.But what is the size of this flower? The ones I've photographed would fill the frame @ 1:4 so they were maybe 2-1/2" in diameter. I have a few stacks if you are interested. I also did a "panorama close-up" stack.
Apr 5, 2015 14:23:10 #
brian43053 wrote:
I posted this one in the close-up forum on Dec 7, 2014. I'm still looking for the original.I would be very interested
Apr 5, 2015 14:25:50 #
brian43053 wrote:
I use A-F for ALL of my macro-photography. Small central spot focus is my preferred method of holding subject in-focus.most times i use manual focus when doing macro but this was just an experiment to see if auto focus would work.
Apr 5, 2015 14:26:42 #
Nikonian72 wrote:
I'm getting there, and my eyes are leading the way, although sometimes the "focus-hunt" drives me nuts.I use A-F for ALL of my macro-photography. Small central spot focus is my preferred method of holding subject in-focus.
Apr 5, 2015 14:28:23 #
brian43053
Loc: Buffalo, NY
LoneRangeFinder wrote:
very nicely done. what you shooting with? what lens did you use?I posted this one in the close-up forum on Dec 7, 2014. I'm still looking for the original.
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