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DPChallenge Forums >> Individual Photograph Discussion >> My Hacked Macro- Photos
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 06/09/2010 03:44:02 AM · #1
Hello all..

Yo_Spiff had asked some time ago for images from my hacked macro (it's a malfunctional Sigma 24-70 f/3.5-5.6)


In response to how this was made, it's fairly simple really...

I was messing around with a dead sigma (for my EOS cams), and I noticed that it seemed to have pretty high magnification when I reversed it (I just hand held it up to the body backwards and moved the body to focus...).. I took a few test shots and determined that there was something to be had here..

So, I took the rear body mounting ring off the lens, and cleared away a bit of junk (had to clip a wire off, etc)... Then I carefully hot-glued the crap out of it to the lens... :)

One thing that was an issue on my first gluing attempt (glad I used hot glue.. It's easy enough to remove, if there's not a ton of it...), was that I managed to lock the zoom in place, this lens has a certain focal length and focus setting that tries to retract the front of the lens barrel into the body of the lens... So, one I figured that out, I extended the barrel and glued the ring to the lens, and mounted it on my body..

I've noticed that I can get well over 3x mag with this (real size vs. size projected on sensor).. So it seems to be a pretty good lens for macro use... Hope this clarifies it a bit.. :)

So, I thought I would finally get around to sharing a few.. And at the same time share a few cool mineral specimens..

Feel free to comment or critique, you won't hurt my feelings any, I promise..
I know the lens isn't technically very good, but I'm happy with the performance for free :)

- Wulfenite on/in green Mimetite
- Yellow Mimetite
- Blue Spangolite with green Brochantite
- Murdochite on Quartz
- Adamite #1
- Adamite #2

Message edited by author 2010-06-09 15:45:21.
 06/09/2010 08:44:57 AM · #2
I ought to do some more macro stuff. Pretty nice, especially for some thing hacked. Appears to have a razor thin DOF.
 06/09/2010 11:16:04 AM · #3
Originally posted by Yo_Spiff:
I ought to do some more macro stuff. Pretty nice, especially for some thing hacked. Appears to have a razor thin DOF.


razor thin :)

Probably my biggest annoyance with this lens is the DOF... Aperture control would be pretty sweet :)
 06/09/2010 02:37:12 PM · #4
Originally posted by coryboehne:
...Aperture control would be pretty sweet :)


I wonder is it possible, since the mount is physically gone, can you poke in and actuate the aperture control mechanism manually? It might be possible.
 06/09/2010 02:39:20 PM · #5
Originally posted by kirbic:
Originally posted by coryboehne:
...Aperture control would be pretty sweet :)


I wonder is it possible, since the mount is physically gone, can you poke in and actuate the aperture control mechanism manually? It might be possible.

Maybe if you can rip it out altogether you could have an f/0.8 lens for shooting in the dark ... ;-)
 06/09/2010 02:42:55 PM · #6
Originally posted by GeneralE:
Originally posted by kirbic:
Originally posted by coryboehne:
...Aperture control would be pretty sweet :)


I wonder is it possible, since the mount is physically gone, can you poke in and actuate the aperture control mechanism manually? It might be possible.

Maybe if you can rip it out altogether you could have an f/0.8 lens for shooting in the dark ... ;-)


Oh, that'd be AWESOME.. Except I'd have difficulty getting an entire atom into focus at once...
 06/09/2010 02:44:29 PM · #7
Originally posted by kirbic:
Originally posted by coryboehne:
...Aperture control would be pretty sweet :)


I wonder is it possible, since the mount is physically gone, can you poke in and actuate the aperture control mechanism manually? It might be possible.


I've not yet figured this out... Although the thought did cross my mind, I couldn't find a lever or anything that seemed to have any effect on it..
 06/09/2010 02:47:08 PM · #8
Could you stick a thin sheet of metal, copper or brass, to the back of the lens with a hole drilled in it about the size of the aperture you want? Like the old brass view camera lenses, or the mirror lenses use?

Message edited by author 2010-06-09 14:48:06.
 06/09/2010 02:57:46 PM · #9
Originally posted by Digipixer:
Could you stick a thin sheet of metal, copper or brass, to the back of the lens with a hole drilled in it about the size of the aperture you want? Like the old brass view camera lenses, or the mirror lenses use?


I don't know if that would work or not... Would the double aperture cause issues?
 06/09/2010 02:59:01 PM · #10
Originally posted by coryboehne:
Oh, that'd be AWESOME.. Except I'd have difficulty getting an entire atom into focus at once...

LOL! Remember, the nucleus is a tiny fraction of the atom's size, and it should still fit within the focal plane OK. The electrons are only probably in any particular place and would look fuzzy anyway, so the DOF issue shouldn't have a noticable effect.

Exactly what have you done to that lens? I missed the introduction to this whole project ...
 06/09/2010 02:59:12 PM · #11
Cory: Please share how you created this lens in the first place, I am very interested!
 06/09/2010 02:59:20 PM · #12
The double aperature shouldnt be a problem--the smallest opening would be the dominant one.

Message edited by author 2010-06-09 15:01:11.
 06/09/2010 03:41:48 PM · #13
Originally posted by Prash:
Cory: Please share how you created this lens in the first place, I am very interested!


I was messing around with a dead sigma (for my EOS cams), and I noticed that it seemed to have pretty high magnification when I reversed it (I just hand held it up to the body backwards and moved the body to focus...).. I took a few test shots and determined that there was something to be had here..

So, I took the rear body mounting ring off the lens, and cleared away a bit of junk (had to clip a wire off, etc)... Then I carefully hot-glued the crap out of it to the lens... :)

One thing that was an issue on my first gluing attempt (glad I used hot glue.. It's easy enough to remove, if there's not a ton of it...), was that I managed to lock the zoom in place, this lens has a certain focal length and focus setting that tries to retract the front of the lens barrel into the body of the lens... So, one I figured that out, I extended the barrel and glued the ring to the lens, and mounted it on my body..

I've noticed that I can get well over 3x mag with this (real size vs. size projected on sensor).. So it seems to be a pretty good lens for macro use... Hope this clarifies it a bit.. :)
 06/09/2010 03:43:42 PM · #14
Originally posted by Digipixer:
The double aperature shouldnt be a problem--the smallest opening would be the dominant one.


And it would be ok for the aperture to be after the last optical element?
 06/09/2010 04:13:42 PM · #15
It's been a few years since I have repaired photo equipment but most of the AF lenses use stepper motors for the aperture and focus. You could try turning the gears to see which one controls focus and which controls the aperture but that may not work if the gears are bad or the aperture is stuck due to oil on the blades.
 06/09/2010 04:27:29 PM · #16
Originally posted by coryboehne:
Originally posted by Digipixer:
The double aperature shouldnt be a problem--the smallest opening would be the dominant one.


And it would be ok for the aperture to be after the last optical element?


Right, thats how the old brass viewcamera lenses( barrel lenses) were constructed. You changed aperatures by inserting a brass disc with the hole in it into a slot at the back of the lens barrel.Some lenses came with 5 or 6 brass inserts.
 06/09/2010 04:38:13 PM · #17
FWIW, I use an old Pentax SMC 50mm f/2 that has a manual aperture ring. ANY old manual ap glass will do for reversing. I took a spare Pentax body cap, drilled it out to basically a mounting ring only. Disassembled a 49mm skylight filter, and epoxy'd its ring, carefully aligned, to the altered body cap, threads out. Screw the lens on, I'm good to go. Exposure is mostly trial and error. DOF is never great, but is noticeably better with smaller aperture, of course.

You can get some pretty nice old glass for a song on e-bay if you can live with manual everything. And if you're reversing it, the manuf. or mount doesn't matter a bit. My periodic table entry "Hydragyrum" was taken with the reversed f/2 rig.


I have all of about $15.00 in it, lens and all, and that SMC f/2 really is a little sweetie...even turned around straight. See my highest scoring pic, the dogwood.

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