[enoxatnep]

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I'm looking to do some extreme macro without forking out for a new lens, and I've learned about the male-to-male coupling rings that allow you to attach the front threads of two lenses together. I have an A 70-210 f/4 and a DA 35mm f/2.8 Macro that I could attach to my camera and a FA 50 f/1.4 that I could couple to either lens (so I would need 49-49mm and 49-58mm coupling rings). Some questions:

- Would this setup allow me to do greater magnification than 1:1 macro, say 2:1, 3:1, etc.? Like, I want to magnify a subject so it fills the viewfinder unlike a typical 1:1 macro lens.
- Is the coupling ring method the cheapest method to achieve this?
- Is this eBay seller and coupling ring good, i.e. has anyone here bought from this/these seller(s), and is the product good or is it typical 'Made in China' crap? Please suggest a better alternative if necessary, i.e. durable metal as opposed to flimsy metal. I don't want my FA 50 to fall off due to a flimsy coupler!

49-49 Male to Male Coupling Step Ring Adapter 49mm Lens Filter Hood Star CPL ND | eBay
49-58mm 49mm - 58mm male-to-male coupling Ring Adapter | eBay

Any other advice/suggestions are welcome.

[Nass]

1) yes, but you may run into vignetting issues, and you'll need to wedge the da open. In any case the 50 will be easier for you, less mag.
2) yes
3) I've spent $100s on extreme macro bits and bobs over the last year and I always recommend a seller called jinfinance. You really, really can't go far wrong with coupling rings though. 90% of "Made in China" 'crap' is better value for money than anywhere else, the downside is usually delivery time rather than quality. Personally I think it's a pretty good deal to get 90% of the quality for 25% of the price, I wouldn't knock Chinese products too much.

[Not a Number]

When using a reverse coupling ring magnification is essentially the ratio of the focal lengths of the two lenses. A 50mm lens on a 100mm lens would give you ~2.0x magnification. 50mm on 200mm would be ~4.0x.

[newarts]

When using a reverse coupling ring magnification is essentially the ratio of the focal lengths of the two lenses. A 50mm lens on a 100mm lens would give you ~2.0x magnification. 50mm on 200mm would be ~4.0x.

The primary lens is the numerator.

OP said......is it typical 'Made in China' crap?

Yes, it is typical 'Made in China' crap? it will meet specifications, will likely be well manufactured and finished, will be delivered in a timely fashion, and does not deserve the arrogant, insulting label of 'crap' sight unseen.

op said...Like, I want to magnify a subject so it fills the viewfinder unlike a typical 1:1 macro lens.

I've never heard of such behavior with a 1:1 macro lens....


Dave in Iowa

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Last edited by newarts; 07-13-2012 at 04:02 PM.

[enoxatnep]

I didn't think I'd get anyone riled up with the "'Made in China' crap" comment, but let's face it - a lot of stuff made there frankly is, due mostly to North American demand for dirt-cheap stuff at the expense of quality. Dollar stores are a prime example. (I'll stop my economic rant at that).

So that's why "crap" is my assumption for these coupling rings when I buy step-up/down ring for filters for $15-$20 at a retailer and see these on eBay for $1.99. I believe my assumption is entirely reasonable, hence why I asked for the listed buyers' and product reputation. However, I suppose that the brick-and-mortar retailer has simply marked the price up 10-20x.

All that said, thank you for the useful magnification info, and I'll look for jinfinance on eBay; the name rings a bell.

[enoxatnep]

"op said...Like, I want to magnify a subject so it fills the viewfinder unlike a typical 1:1 macro lens."
I've never heard of such behavior with a 1:1 macro lens....

Example: Last week I was trying to shoot a water droplet on a flower petal, but I was literally fractions of an inch from the droplet with my DA 35 Macro yet the droplet occupied only a small portion of the center of the image. Now, I'm not sure if a 100mm or 200mm 1:1 macro would 'magnify' the droplet, i.e. make it much larger in the image, but I don't want to pay the cost for that. Hence, my exploration for better (and much cheaper) macro magnification options. I hope this clarifies my original statement.

[Moo]

I cheated for this purpose and just taped two step up rings together...

[newarts]

Example: Last week I was trying to shoot a water droplet on a flower petal, but I was literally fractions of an inch from the droplet with my DA 35 Macro yet the droplet occupied only a small portion of the center of the image. Now, I'm not sure if a 100mm or 200mm 1:1 macro would 'magnify' the droplet, i.e. make it much larger in the image, but I don't want to pay the cost for that. Hence, my exploration for better (and much cheaper) macro magnification options. I hope this clarifies my original statement.

I see, I thought you meant the 1:1 image from the macro lens didn't fill the viewfinder in that it was vignetted, while you meant the magnification wasn't high enough. A 200mm or 100mm macro lens set at 1:1 magnification would give you exactly the same results as your 35mm macro lens.

Your viewfinder shows you what the sensor sees & the sensor is 23.6mm wide. You can estimate the magnification you need by dividing the sensor width by the subject width; for a 5mm water droplet, mag = 23.6/5 ~ 4.7x would fill the screen with droplet.

These estimates needn't be precise so it can be useful to think in terms of inches. The sensor is roughly 1" wide; a magnification of 2x would cover an area 1/2" wide, 4x would cover 1/4" etc.

Dave in Iowa

[JimJohnson]

As a former retailer 30+ years ago, I can tell you that many smaller items are marked up multiple times over the retailer's cost. It has to do mostly with how fast you can sell such items. The longer an item sits in inventory, the greater the overhead due to storage, insurance and 'touch' costs - that last item especially. A retailer is paying somebody every time an item is moved, cleaned, inventoried, explained to a customer or the sale entered into the accounting system. Those costs are about the same regardless of the item to be sold. Let's face it, a M-M threaded lens reversal/joining ring will only be purchased by a small fraction of the photographic market. As a full-service retailer I might stock such an item, but I'm going to charge a stiff price. And the final twist of the knife ... the retailer is also looking for the least expensive source that isn't crap - and may be buying the same Chinese item you are considering.

[Allison]

The 35 and the 100 are going to give you the same magnification, but the 100 would allow you to to be farther away for the same effect. People who shoot critters usually prefer the longer macros like the 100 because they aren't so close to scare the critter off.

The coupling ring will do what you want, but as mentioned above you need to watch for heavy vinyette. You will also want to bring in some extra light. I went with the extension tube route to do the same thing and it does eat up some light. The advantage to using the expensive extension tubes (compared to the extension tubes without contacts or the coupling ring) is that they allow for aperture control. Your da doesn't have an aperture ring, so controlling this without the lens being attached to the camera is tricky. But the kenko extension tubes with contacts are somewhat rare and reaching the $100 point that you are talking about.

Since you have lenses with aperture control to use on the coupling ring, I would go for it. $1.99 is cheap and shouldn't make a big deal if it doesn't work as well as you hoped. I wouldn't pay more for the $15 ones because those are probably made in china too, but just marked up more. Post some pictures of the set up and your results once you get to try it out.

[Nick Siebers]

I had 2 extra UV filters, so I glued them, together with male screws out and then smashed out the glass. Works fine, but I keep a hand on there just to be sure. I use a 50 on an 80-200, with good results. But you need a LOT of light, and it mostly works at high magnification (100-200mm on the zoom). Here is a shot I did of a feather with a 28mm on the 200mm (about 7:1 magnification)

[Allison]

I had 2 extra UV filters, so I glued them, together with male screws out and then smashed out the glass. Works fine, but I keep a hand on there just to be sure. I use a 50 on an 80-200, with good results. But you need a LOT of light, and it mostly works at high magnification (100-200mm on the zoom). Here is a shot I did of a feather with a 28mm on the 200mm (about 7:1 magnification)

Your DIY approach is impressive, but I am not going to lie, I would rather spend 1.99 and a long shipping than do all this! The feather magnification is cool.

[GibbyTheMole]

Everything Nass said = true.

The Chinese "crap" is a whole lot better than it used to be. It's not all terrific, but a lot of it is quite good, and a few things are downright excellent. People dissed Japanese made goods as "crap" in the early days. But it got better. China is the new Japan.

Plus, there's not a lot that go wrong with a threaded metal ring.

Also, remember Pentax DSLRs are made in the Philippines, and a lot of their lenses are made in Vietnam. Neither of those places have a stellar reputation for the quality of their manufactured goods, and the Pentax stuff turns out alright.

[mee]

One thing I don't think has been mentioned yet is once you get beyond 1:1 your Depth of Field gets INCREDIBLY small.. as in.. a millimeter or so. Forget hand-holding a rig like this unless you don't breath and have super steady hands (aka you are a robot - that would be amusing a robot making use of another machine)

I set 68mm of extension tube + 105mm 1:1 Macro + 28mm SMC M lens reversed and yeah it has incredible close-up range, but even attached to a sturdy tripod, I have to set the timer and hope no vibrations upset the focus. Very powerful. It also looks like a mini-howitzer fully extended.

You would probably need to invest in some sort of focus stacking software at this point and take multiple shots at different points on your subject to get a decent final image.