info about setup upgrade

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elfuma
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Joined: Thu Oct 17, 2013 7:00 am

info about setup upgrade

Post by elfuma »

Hi All,

I’ve begun few months ago with extreme/stacking macrophotography by reading the interesting tutorial (provided by Rik) about objective setups on camera. In these weeks, after a lot of practice and experimentation, I've collected some questions that I would like to ask you.

Currently I’m using a Nikon Plan 10x infinity corrected (MRL00201) coupled with a Sigma 180mm f/2.8 to get a 9:1 on my Nikon D800 camera (StackShot and ZS to collect and finalize the images). I would like to go beyond the 10x magnification, so I'm looking for a 20x or 40x objective (I'm aware that things will become even harder to manage, but I like to experiment).

Provided that my budget is around 600$, my questions are:

- Among the infinity corrected objectives, which one would you suggest me to buy?
- Since I've no high quality lenses at (or longer than) 200mm to be coupled with infinity objectives, would it be better to look at a finite objective (w/bellows) ? In this case, would you be so kind to suggest me one of them?
- Or, would it be better to mount the infinity objective on the Raynox DCR-150 (or similar) on bellows?
- Is there some book about extreme/stacking macrophotography that I could buy, so I could stop bothering you with dumb questions.. :)

Thank you in advance for your precious help,

Luca

Chris S.
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Post by Chris S. »

Luca,

If your Sigma 180mm f/2.8 is working well for you as a converging lens for a 10x infinity objective, I’d suggest you keep using it—at least for a while. It’s likely to also work well with higher magnifications, too. In the future, once you are comfortable working at higher magnifications, you might want to test other converging lenses against your Sigma, and see if they offer any improvements that matter to you. But for now, it’s almost certainly not something you need to worry about.

For 20x on a converging lens, the obvious candidate is the Mitutoyo Plan Apo 20x/0.42 (not the similar, but “SL” designated, 20x/0.28, which has less resolution). Your budget won’t cover a factory-fresh specimen, but might get you a nice second-hand one—especially if you have room to stretch a bit.

If you have a bellows, you can also consider the (finite) Nikon M Plan ELWD 20x/0.40, which is usually less expensive than the Mitutoyo. This lens has not been in production for some time, but can often be found on the secondary market. This objective delivers very good quality, though with some chromatic aberration (purple fringing in high-contrast regions) that the Mitutoyo is largely free of. We would expect this, since this Nikon lens is specified as an achromat, and the Mitutoyo as an apochromat. In many cases, this sort of CA becomes much less evident in stacked images. Another difference between the two lenses is the working distance: The Mitutoyo 20x/0.42 objective’s WD is 20mm, while the Nikon ELWD 20x/0.42 objective’s WD is 10.5mm. Either of these working distances is quite workable—but longer WD does make things a bit easier.

Remember that ALL used objectives need to be purchased with a return privilege, and must be tested against a known benchmark prior to acceptance. This applies even to objectives that are cosmetically perfect. In my experience, about one in ten used objectives needs to be returned.

I suggest that you don’t move to 40-50x until you’re comfortable at 20x. At that point, the suggestions will parallel those for 20x. Look at the Mitutoyo 50x/0.55 on the converging lens, or the Nikon M Plan ELWD 40x/0.5 on the bellows.

Be aware that resolution does not scale with magnification, but with numerical aperture (“NA”—the number listed after the magnification and front-slash in the objective specifications). So when purchasing a new lens, base your expectations for increased resolving power on the additional NA, not the additional magnification.

Also—not sure whether you’re using your D800 in full-frame mode, Aps-C crop mode, or the crop mode partway between the two. Any of the lenses I’ve listed here will work well in covering the APS-C portion of the frame. But when you project their image circles on larger portions of D800 sensor, you’ll be including lower-quality portions of the image circle. This may or may not bother you for a given subject, will primarily affect the corners, and will vary with each lens model. When you get to the point of pushing into this sort of issue, you might want to also think about testing additional converging lens approaches.

Cheers,

--Chris

rjlittlefield
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Post by rjlittlefield »

Edit: I see that Chris S posted while my message was sitting in draft. His is more comprehensive, but I'll post anyway to add a bit of complementary information and links. I second Chris's recommendation for the Mitutoyo 20X if you can stretch the budget a bit.

Luca,

I do not know of a book you can buy. As far as I can tell, the leading edge of extreme/stacking macrophotography is being developed & reported by members of photomacrography.net, so this is your best source of info.

For full frame cameras, my current recommendation for tube lens is the Raynox DCR-150 on bellows or tubes. (Be sure to check for glare reflecting from the insides of all components!) See http://www.photomacrography.net/forum/v ... hp?t=23898 for discussion. As Chris says, if the Sigma 180 is working OK for you, then just keep using it. But I see in another post that you're having some problems with corner darkening, which the Raynox would resolve.

For a 20X objective, the tradeoffs are more painful than at 10X.

At 10X, the Nikon CFI and CFI BE objectives are inexpensive and provide good sharpness across a full-frame area; they suffer mainly from longitudinal CA (especially purple haze) as shown at the above link.

But at 20X, I do not know any objectives that are inexpensive, sharp, and have a good working distance, even allowing for significant CA.

At the $600 price point, I think your best bet would be any of several Nikon objectives that are labeled as M Plan or EPI. Some of these are finite, others infinite. The CF Plan 20x/0.40 ELWD ∞/0 WD 11.0mm EPI is often found on eBay. See http://www.photomacrography.net/forum/v ... hp?t=22044 for comparison against the Mitutoyo M Plan Apo, which is the best lens I know at this magnification. But note that comparison was on APS-C, not full frame. I do not know how well the CF Plan covers full frame. (See http://www.photomacrography.net/forum/v ... 210#149210 for an image recently shot with the Mitutoyo 20X on D800E.)

--Rik

elfuma
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Post by elfuma »

Chris, Rik, thank you very much for your suggestions and help

I'm looking around for the objectives you mentioned. I've seen the price of a used Mitutoyo and it's far from what I can currently afford, so I think I will go with the finite "Nikon M Plan ELWD 20x/0.40" or with the infinite "CF Plan 20x/0.40 ELWD ∞/0 WD 11.0mm EPI", provided that I'm aware of the risks that quality and full frame compatibility could not be good.

Let me ask you a couple of questions more about the mechanical parts to fit the objectives on the camera body:

- With finite objective, I would prefer to use the bellows with Nikon F bayonet instead of Pentax threaded tubes (I’m referring to the very good explanation made by Rik in this topic: http://www.photomacrography.net/forum/v ... hp?t=12147). In this case, the parts will be: finite objective --> RMS to M42 cone/ring adaptor --> M42 to Nikon F bayonet ring adaptor --> Nikon bellows --> D800. Is it correct?

- With infinite objective, it's not clear to me how should I mount the Raynox on the bellows, since the Raynox - if I did not misunderstood - should have some kind of lens thread but nothing like a Nikon F bayonet to fit on top of bellows..I’m sorry for my unclear explanation.. Could you kindly suggest me a assembly “chain” with the parts to be bought?

Thank you again for your help,

Rik, the images of the Sunset Moth are awesome. Me and my partner were speechless..

Luca

rjlittlefield
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Post by rjlittlefield »

elfuma wrote:- With finite objective, I would prefer to use the bellows with Nikon F bayonet instead of Pentax threaded tubes (I’m referring to the very good explanation made by Rik in this topic: http://www.photomacrography.net/forum/v ... hp?t=12147). In this case, the parts will be: finite objective --> RMS to M42 cone/ring adaptor --> M42 to Nikon F bayonet ring adaptor --> Nikon bellows --> D800. Is it correct?
That sounds correct to me. If you use a cone, be sure to check the inside for reflections that will produce veiling glare. It seems that every cone adapter on the market needs to be flocked by the user.

By the way, in some orientations you may need to stick a short tube between the bellows and camera body in order to get clearance. In that case, be sure to use a thin-wall tube that just does the mechanical connection. If you use an automatic tube that couples the electrical signals, the thick wall of the tube will end up masking the corners of your sensor. The result looks like a really hard vignette.
With infinite objective, it's not clear to me how should I mount the Raynox on the bellows, since the Raynox - if I did not misunderstood - should have some kind of lens thread but nothing like a Nikon F bayonet to fit on top of bellows..I’m sorry for my unclear explanation.. Could you kindly suggest me a assembly “chain” with the parts to be bought?
At http://www.photomacrography.net/forum/v ... 195#143195 there's an itemized list of the adapter chain I use on APS-C. For full frame, it's the same except that instead of the cone I use a flat adapter that moves the objective several cm closer to the Raynox. That prevents vignetting.

Going with M42 on the objective end makes it simple to insert an iris. Alternatively, you can stay with 52mm until you drop down to fit the objective. In that case it's probably a good idea to insert a 52mm extension tube to keep the objective 30 mm or so away from the Raynox. That seems to improve the image quality a little. That's the rig I used to shoot the Sunset Moth, using a 52mm tube that is 14 mm long. Unfortunately, 52mm extension tubes are becoming oddly difficult to find. They used to be commonly available on eBay, but first one length disappeared, and now I can't find any at all there. I have no idea what's going on. You can still get them at Amazon, though.
Rik, the images of the Sunset Moth are awesome. Me and my partner were speechless..
Thanks. Most of my images of moth scales are pretty boring, but this species is nothing short of spectacular, especially at high power.

--Rik

elfuma
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Joined: Thu Oct 17, 2013 7:00 am

Post by elfuma »

Rik, thank you for your explanation.

I’m collecting the items I need according to your suggestion to look at your reply here http://www.photomacrography.net/forum/v ... 195#143195 , and with the replacement of the M42 tubes with bellows.

Then, for the infinite corrected obj. setup with Raynox, the chain should be:

Objective --> RMS to 52mm male adaptor ring (or RMS to M42 + M42 to 52mm male) --> 52mm female to 52mm male / 14mm length --> 52mm female to 52mm female ring --> 52mm male to 43mm female ring --> reversed Raynox 150 --> 49mm male to Nikon F bayonet adaptor ring --> Nikon F mount bellows (clearance is ok, so no need of extension tube) --> Nikon D800.

I think I’ve found everything except the 52mm female to 52mm female adaptor. Reading the topic reported above, it’s not so clear to me what you did to work around to this point and reported as “55mm male to 52mm female step-down ring, used here as a 52-mm female to 52mm female reversing adapter. (That is, the 55mm male thread is not used.) “. Did you mean that the 55mm male to 52mm female have a second thread (52mm female) by the male side of the ring? (sorry for most probably dumb question).

Thank you, Luca

rjlittlefield
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Post by rjlittlefield »

elfuma wrote:I think I’ve found everything except the 52mm female to 52mm female adaptor. Reading the topic reported above, it’s not so clear to me what you did to work around to this point and reported as “55mm male to 52mm female step-down ring, used here as a 52-mm female to 52mm female reversing adapter. (That is, the 55mm male thread is not used.) “. Did you mean that the 55mm male to 52mm female have a second thread (52mm female) by the male side of the ring? (sorry for most probably dumb question).
Effectively, yes. On my reducing rings (from Fotodiox), the internal thread simply goes all the way through. So, a ring that is nominally 55mm male and 52mm female can also be used as a double-ended 52mm female. I've edited the linked post to clarify this point.

--Rik

elfuma
Posts: 21
Joined: Thu Oct 17, 2013 7:00 am

Post by elfuma »

Rik,

Now everything is clear : ) I've found and bought the Fotodiox threaded all the way thorugh on Amazon

I hope to receive and test everything soon,

Rik, Chris, thank you again for your help!

Luca

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