Macro - Reverse mounting.. - DPChallenge Forums

04/20/2006 07:22:27 AM · #1

So dudephil produced a great shot for Texsture 3 by reversemounting a 50mm on to a 300mm lens.

At home I have a great little thingy that reverse mounts an 18mm lens direct to the camera body and I've had some pretty fun shots with it eg:

With my current set up, I have to set the aperture to 32 in order to get more of the image into focus but then it is REALLY dark and really hard to get it in focus in the first place.

So what advantages are there to doing it my way and doing it like dudephil did???

Anyone got any comparison pics of the two techniques????

04/21/2006 04:20:13 PM · #2

bump!!!

Anyone got reverse advice?

04/21/2006 04:29:03 PM · #3

Originally posted by cbonsall:

bump!!!

Anyone got reverse advice?

Wouldn't reverse advice actually reduce your knowledge??

04/21/2006 04:35:44 PM · #4

Originally posted by kirbic:

Wouldn't reverse advice actually reduce your knowledge?

I thin you might have just suceeded in giving reverse advice!!

04/21/2006 04:35:57 PM · #5

I haven't experimented with a plain reversed lens, as opposed to reversing on another lens. The latter scenario has the advantage of not requiring a complicated adapter, just a cheap macro coupling ring ($8USD). A plain reversed lens could potentially be used in such a way as to retain communication with the camera, so you could get automatic aperture operation. The adapter is expensive, though. In fact, reversing on another lens means that the aperture in the reversed lens just stays wide open anyhow, so there's no disadvantage (aperture is controlled by the diaphragm in the normally-mounted lens).
Overall, I don't see a huge advantage in using a single, reversed lens. Someone with direct, relevant experience might prove me wrong though.

Tamron SP AF 17-50mm f/2.8 Di II LD Aspherical (IF) for Canon

04/21/2006 04:36:33 PM · #6

Originally posted by cbonsall:

Originally posted by kirbic:

Wouldn't reverse advice actually reduce your knowledge?

I thin you might have just suceeded in giving reverse advice!!

Oh, the irony, LOL!

Phil

Canon EOS-7D

04/21/2006 04:47:44 PM · #7

Hello CB. I appreciate the compliment. After a couple of requests, I submitted a tutorial a few days ago so maybe it'll be posted up shortly.

Good shot on this fly you got there. As you've discovered, light is key here - the more the better. Mine is a 10 second shot at f25 in a light tent. Couple of things - Did you manually open the aperture on the reversed lens? If not, that'll help somewhat. Also, if you've reverse mounted a single prime lens to the camera it will definitely be more difficult to pull off. When you have a prime reversed with a telephoto lens you can place the subject then just use the zoom for getting in on the level you wish to be in focus.

PhantomEWO

Canon EF 70-200mm f/2.8L IS USM

04/21/2006 04:50:34 PM · #8

Originally posted by kirbic:

Ya got a link for one of these cheap macro coupling rings for $8 for a Canon 20D outfit?
Thanks

04/21/2006 04:53:49 PM · #9

Here is what I spoke of. You need to know the two lens thread sizes, and get a ring that has both size threads. For instance, to use the 50/1.8 (52mm filter threads) on the 100/2.8 Macro (58mm threads), get a 52 to 58mm coupler.

PhantomEWO

Canon EF 70-200mm f/2.8L IS USM

04/21/2006 04:56:13 PM · #10

Originally posted by kirbic:

Thanks, that makes it easier to visualize now, will have to give it a try.

SDW

Canon EOS-60D

Tamron AF 28-300mm f/3.5-6.3 XR Di LD Aspherical IF for Canon

04/21/2006 05:34:57 PM · #11

Can you reverse mount a canon 70-300mm IS and a canon 50mm f/1.8 II? And would there be some adverse effects for having such a zoom lens mounted to the camera? The only other lenses I have is the Tamron 28-75 f/2.8 Di and the canon kit lens 18-55mm.

The only two lens with the same size is the canon 70-300 IS and the canon 50mm f/1.8 II. The Tamron is much larger and the kit lens is a 58mm.

Phil

Canon EOS-7D

Tamron SP AF 17-50mm f/2.8 Di II LD Aspherical (IF) for Canon

04/21/2006 05:53:48 PM · #12

Originally posted by Southern Gentleman:

Shouldn't be a problem. With the 70-300 at full zoom mounted to the 50mm you will have a 6:1 ratio.

Ecce_Signum

Canon EF 17-40mm f/4.0L USM

04/21/2006 06:19:32 PM · #13

I've played with the reverse mounting, seriously good fun but difficult to get stonking images (for me).

Another fun thing to try is using bellows and lens :)

this

produced this

Its cropped a touch for composition, I liked the idea of using the 'bet' from Elizabeth (she is 80 today).

ShorterThanJesus

Nikon D300

04/21/2006 06:47:47 PM · #14

Are there bellows generally available for purchase or is this the kind of thing one purchases at garage sales, flea markets, or at ridiculously inflated prices from collectors?

Ecce_Signum

Canon EF 17-40mm f/4.0L USM

04/21/2006 06:51:18 PM · #15

Originally posted by ShorterThanJesus:

Are there bellows generally available for purchase or is this the kind of thing one purchases at garage sales, flea markets, or at ridiculously inflated prices from collectors?

Am sure if you look around flea markets etc you'll find them pretty cheap, mine cost me Â£60 on Ebay and I probably got bidding fever but they are way cool and take a half decent pic to boot :)

edited to say ...

I was lucky but would be best to see the bellows and check there are no pin holes.

Message edited by author 2006-04-21 18:54:39.

04/22/2006 05:31:15 PM · #16

hmmmmm I might look into getting a mount to reverse a lens on the end of another lens.

The mount I have was <Â£15 on ebay, its basically a canon lens mount to male 58mm. The magnification is pretty impressive but like you've said the issue is light.

At F5 its quite light so its easier to get the subject in focus but the depth of field is miniscule. Using the "depth of field" preview button on the 350 I'm able to manually set the lens to be F36 so I can get more in focus but its so blooming dark its very very difficult to get the item in focus, even with lots of extra lights.

David.C

04/22/2006 06:48:56 PM · #17

Hope no one minds me taking a bit of a tangent here, but as I have been curious of this I have a few questions.

I currently have the 50mm f1.8, but my second lens is in the mail (28-200 f3.8-f5.6). The problem is I'm not seeing a 62mm/55mm coupler. Does such a thing exist? I realize there will be some vignetting with the reduction in size, but is it even possible?

For the reversed lens, it was mentioned the aperture should be left wide open, but what about focus? Just leave it at infinite?

How do DOF charts work with reversed lenses, both singly and in combination?

I understand how to figure zoom magnification of a lens (max focal length/min focal length), but how does turning the lens around affect it? How does putting another lens in front of another affect the focal length?

I know, too many questions. :(

David

David.C

04/22/2006 07:46:33 PM · #18

Originally posted by David.C:

... I currently have the 50mm f1.8, but my second lens is in the mail (28-200 f3.8-f5.6). The problem is I'm not seeing a 62mm/55mm coupler. Does such a thing exist? I realize there will be some vignetting with the reduction in size, but is it even possible? ...

Nevermind, I found the step-up and step-down rings. Seems I have the choice of stepping up the 55mm to 62mm or stepping down the 62mm to 55mm. I may be missing something, but would there be a difference other than preference and availability?

David

04/22/2006 07:54:26 PM · #19

Originally posted by David.C:

I currently have the 50mm f1.8, but my second lens is in the mail (28-200 f3.8-f5.6). The problem is I'm not seeing a 62mm/55mm coupler. Does such a thing exist? I realize there will be some vignetting with the reduction in size, but is it even possible?

Yep, the vignetting could be significant; I used to have a copy of the 28-200, and as I remember the front element covers almost all of that 62mm. It will still work, if you can adapt it. You can use a macro coupler and step ring in combination. Try looking for a 62-58mm step-down ring (needs to be step *down*) and a 55-58 macro coupler. There should be *some* combination of step ring and coupler that will work.

Originally posted by David.C:

For the reversed lens, it was mentioned the aperture should be left wide open, but what about focus? Just leave it at infinite?

Focus on the reversed lens has little effect. Leaving it at infinity is fine.

Originally posted by David.C:

How do DOF charts work with reversed lenses, both singly and in combination?

Normal DoF charts (distance based) are almost useless in the macro range. In the macro range, use this relationship:

DOF = (2*CoC*fstop*(m+1))/(m*m)

Use 2*sensor pixel pitch as the CoC; m is the magnification. Using this relation, if you know wht magnification you're shooting at (usually easy to determine) you can calculate the DoF. The usual answer is, "damn narrow", LOL.

Originally posted by David.C:

I understand how to figure zoom magnification of a lens (max focal length/min focal length), but how does turning the lens around affect it? How does putting another lens in front of another affect the focal length?

When you reverse a lens on a zoom lens, turning the zoom ring will change the magnification of the pair, since the overall magnification is related to the ratio of the focal lengths.

EDIT: Corrected formula for macro DoF!

Message edited by author 2006-04-22 20:24:13.

David.C