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09-06-2010, 09:01 PM   #1
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Will the converter fit?

Amazon.com: Raynox DCR 150 - Converter: Camera & Photo

I'm confused as to if this converter (a Raynox 150 if u don't want to bother with the link) will fit on my SMC 50mm 1.7 prime. It says it has a 52-67mm snap on adapter but it says the filter size is 49mm. My prime is 49mm.

I'm looking for a cheap way to experiment with macro and was hoping this setup would work.

Thanks

09-06-2010, 09:11 PM   #2
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Wow that's a mess of a description, I counted 4 different thread sizes mentioned
09-06-2010, 09:15 PM   #3
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QuoteOriginally posted by chucuyuco Quote
Amazon.com: Raynox DCR 150 - Converter: Camera & Photo

I'm confused as to if this converter (a Raynox 150 if u don't want to bother with the link) will fit on my SMC 50mm 1.7 prime. It says it has a 52-67mm snap on adapter but it says the filter size is 49mm. My prime is 49mm.

I'm looking for a cheap way to experiment with macro and was hoping this setup would work.

Thanks
I have either this raynox or the 250 one, with the snap on adapter. I can somewhat force it to fit my prime lenses with 49mm thread size, but I wouldn't recommend you to. Now I'm using a step up ring, 49 to 52mm and snap the raynox onto the step up ring instead.

If you choose not to use the adapter, then you need a step down ring from 49 to 43mm (which is the raynox lens thread size).

Regarding the 49mm filter size, yes it has threads in front of the actual lens (not the snap on adapter) where you can put filters if you like. Could be wrong though, this is all from memory.

Last edited by sajah; 09-06-2010 at 09:21 PM.
09-06-2010, 09:19 PM   #4
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thanks sajah,

the step ring doesn't affect IQ because of the extra space between the glass? And what is the 49mm filter size they are talking about then?

LOL sorry future retro

09-06-2010, 09:21 PM   #5
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QuoteOriginally posted by chucuyuco Quote
thanks sajah,

the step ring doesn't affect IQ because of the extra space between the glass? And what is the 49mm filter size they are talking about then?

LOL sorry future retro
Just to be clear I was talking about the description on Amazon

I hate sloppy descriptions like that, especially on Amazon
09-06-2010, 09:49 PM   #6
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QuoteOriginally posted by chucuyuco Quote
the step ring doesn't affect IQ because of the extra space between the glass?
A stepping ring introduces less unnecessary space than the clip-on adapter. I find the stepping ring a much better solution than the clip-on adapter.

QuoteQuote:
And what is the 49mm filter size they are talking about then?
I believe the *front* of the Raynox has 49mm threads, relevant if you're going to stack another filter on top - or if you wish to put use a lens cap on it.
09-06-2010, 10:09 PM   #7
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that makes sense, thanks marc.

maybe extension tubes would be an easier less expensive solution?

09-06-2010, 10:53 PM   #8
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or should i go with the Raynox 150 and use it with my kit 55-300?
09-07-2010, 12:23 AM   #9
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I started my macro life with a Raynox 150 and the da55-300 and after buying a couple of dedicated macro lenses, STILL find the Raynox/da55-300 to be a fun and effective way to get shots. It allows me to take a walk with only the da55-300 and nothing in my pockets but the clip-on Raynox for the bug shots.
09-07-2010, 01:25 AM   #10
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QuoteOriginally posted by chucuyuco:
maybe extension tubes would be an easier less expensive solution?

...or should i go with the Raynox 150 and use it with my kit 55-300?
With a Raynox adapter, you keep full lens automation on A and AF lenses. This is important if you're shooting with flash. Only 3rd-party signal-feed-thru tubes MUCH MORE EXPENSIVE than Raynox will provide such automation with your kit lens or any other AF lens you put on your camera.

For your 50/1.7, it's a different story, sort of. You didn't say whether it's M42 or K- or M- or A-type. I often use DCR-250 on my FA50/1.4 -- yeah, I must squeeze the adapter lugs a little, but it's no big deal, although a step-down ring is a little more elegant. But the Raynox snap-on is handy for many many lenses. Just remember that a Raynox or other +diopter adapter is less effective at longer focal lengths. A Raynox on your kit lens will magnify much more at 55mm than at 200mm.

If your 50/1.7 is M42 or K- or M-type, then tubes are cheap (usually <US$10) and clean (no distortion).

I love tubes and bellows. I use both, for macro and general photography. A cheap flat-field enlarger lens on bellows is crisp and sharp everywhere. But a good place to start with your 50/1.7 is a set of cheap PK-mount tubes and a 49mm-PK mount reversal ring. Most non-macro primes deliver a sharper image when reversed for close-up work. As with everything, there are trade-offs, pros and cons:

* Any extension gives cleaner results than any adapter.
* Reversed lenses lose all automation. Aperture rings are required.
* No non-reversed lens can focus closer than its focal length.
* If not reversed, shorter focal lengths work closer than longer FL's.
* Reversed, the working distance is always the lens register, ~45mm.
* More magnification means less light means longer exposures.

What this boils down to is: Tubes are cheaper, slightly cleaner, and manual. A Raynox works great on an 18-55 kit lens, is IMHO less impressive at 200mm, and lets you keep automation. (And it's very very handy!) I hope this info helps.

Last edited by RioRico; 09-07-2010 at 01:32 AM.
09-07-2010, 10:21 AM   #11
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QuoteOriginally posted by RioRico Quote
Just remember that a Raynox or other +diopter adapter is less effective at longer focal lengths. A Raynox on your kit lens will magnify much more at 55mm than at 200mm.
That's true for extension tubes, but backwards for closeup lenses like the Raynox. These work by setting focus to a more or less fixed distance (around 6-8" in the case of the 150), so the *longer* the focal length, the more magnification your get. The Raynox 150 on the kit lens is barely worth the trouble, but the Raynox 150 on the 50-200 at 200 gives better than 1:1.

The difference in price between the Raynox and a set of extension tubes is pretty insignificant - either way, you get change back from a $50. The Raynox has the advantage of provide 1:1 magnification at longer focal lengths - meaning greater working distance - as well as being smaller and more convenient to use. The extension tubes have the advantage of somewhat better IQ (but the Raynox is pretty darn impressive - see the Raynox Club thread on this forum).
09-07-2010, 02:09 PM   #12
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I started to include a theory section in my previous post but thought it too pedantic. Sigh. Here's what's up with diopters AFAIK:

Raynox and similar adapters label their glass by focal length: the DCR-150 is 150mm, etc. Diopter is calculate as the 1-meter inverse of the focal length. So a DCR-250 is 1000/250= +4 dpt, and a a DCR-150 is 1000/150= +6.66 dpt. Diopters are additive. A DCR-250 on a 50mm lens gives (1000/250)+(1000/50)= 4+20= +24 dpt. A DCR-250 on a 200mm lens gives (1000/250)+(1000/200)= 4+5= +9 dpt, considerably less.

The Wikipedia entry on Magnifying Glass says that with the subject in focus, magnification is given by M = (DPT / 4) + 1. So the DCR-250+50mm lens combo has M = (24/4)+1= 7x. And the DCR-250+200mm lens combo has M = (9/4)+1= 3.25x. So there's over twice the magnification with 50mm than with 200mm. (I don't use the DCR-150 in these examples, in order to avoid an overflow of pesky decimals.)

I'll be happy if someone corrects me on this. I want to make sure it's right.
09-07-2010, 03:47 PM   #13
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QuoteOriginally posted by Marc Sabatella Quote
These work by setting focus to a more or less fixed distance (around 6-8" in the case of the 150), so the *longer* the focal length, the more magnification your get.
Absolutely. My R-150 on the da55-300mm easily demonstrates that fact.

Rio, you are way ahead of me as I long ago forgot all my optics classes but the one factor that does not seem addressed in your researched formulas is distance. Unless there was an assumption that all focus distances happens to equal the FL for discussion purposes, then doesn't it have to enter the equations? or did I flat miss something it is based on?

Just to confuse myself more, I took my 1:1 Tamron 90/2.8 and verified the 1:1 by shooting a metric scale at minimum distance for all tests and it did indeed cover an area almost exactly the same as the sensor.
I then added a Pentax AF1.7x TC and went from 1:1, up to 1.7:1. Seems simple enough.
I removed the TC and added a Raynox-150 and measured 1.5:1
I added the TC and the Raynox-150 and magnification measured 2.5:1.

Now I sit here with equations trying to calculate the same but I'm still lost in the woods.

No way I can get those numbers with equations.

Last edited by imtheguy; 09-07-2010 at 09:35 PM.
09-07-2010, 06:52 PM   #14
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thanks for all the great insight... I'm going to go with the raynox 150 and I found a local shop that has a cheap adaptor so I'll be able to use it on my 55-300 and my 50 prime. That'll do for now
09-07-2010, 09:18 PM   #15
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QuoteOriginally posted by RioRico Quote
The Wikipedia entry on Magnifying Glass says that with the subject in focus, magnification is given by M = (DPT / 4) + 1. So the DCR-250+50mm lens combo has M = (24/4)+1= 7x. And the DCR-250+200mm lens combo has M = (9/4)+1= 3.25x. So there's over twice the magnification with 50mm than with 200mm. (I don't use the DCR-150 in these examples, in order to avoid an overflow of pesky decimals.)

I'll be happy if someone corrects me on this. I want to make sure it's right.
Well, it's definitely *not* right, but I can't say why exactly. With the Raynox 150 on a 50mm lens, maximum magnification is in the 1:4 range or so depending on minimum focus distance of the lens itself (around 1:6 at infinity). With the Raynox 150 on a 200mm lens, it's already over 1:1 even at infinity.

Looking at the diopter calculation, something is already off - the 150 is not higher diopter than the 250. It's the other way around. So something is wrong with either the calculation of the diopters, or the assumption about the focal length of the 150 and 250, or both. Anyhow, it's hard to say if the answer would have come out right otherwise or not.
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