Trying to pick first 10x (Canon + bellows)

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luna
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Joined: Sun Jul 24, 2011 1:04 pm

Trying to pick first 10x (Canon + bellows)

Post by luna »

I'm working on setting up an indoor studio with some of my macro equipment and want to pick up a 10x, but I need a little assistance. I shoot Canon and have a few macro lenses: Canon 100/2.8, Volna-9 50/2.8, Tomioka 60/2.8, and an MP-E (currently on its way). I also have extension tubes and bellows, and I'm planning to start with the latter (unless you have other advice).

I read through this thread about the Nikon CFI Plan Achromat 10x NA 0.25 WD 10.5mm: http://www.photomacrography.net/forum/v ... php?t=9664

I also saw this one about the Nikon 10X NA 0.25 160/-: http://www.photomacrography.net/forum/v ... php?t=9393

I can find both for sale, and there isn't a huge price difference. Is one or the other better quality wise or just better for my setup? Is there another 10x you'd recommend?

rjlittlefield
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Post by rjlittlefield »

luna, welcome aboard!

I'm the fellow who wrote both those threads. I also wrote the FAQ: How can I hook a microscope objective to my camera?, which I recommend reading also.

The two objectives that you've mentioned have very different characters.

The first one is an "infinity" design that has to be used in conjunction with another long lens to complete the image formation. If you stick it naked on bellows, it will make an image but the quality will be degraded quite a lot.

The second one is a "finite" design that is appropriate to be used by itself on bellows or extension tubes. It is in the same general category as the Nikon CF N Plan Achromat 10X NA 0.30 that is shown at the start of the FAQ.

Any of these three objectives will do good work.

If you have a 200 mm telephoto to use it with, then I recommend getting the Nikon CFI Plan Achromat 10x NA 0.25 WD 10.5mm described at your first link. In addition to being very nice at 10X on a 200 mm telephoto, that lens also has wide enough coverage to work well at lower magnifications on shorter telephotos such as 135 mm or even 105 mm. Essentially it's both a very good 10X and an extraordinary 5-7X, depending on how long another lens you pair it with.

On the other hand, if you prefer to work with bellows then you'll need one of the other two. The CF N Plan Achromat 10X NA 0.30 was my "first love" in Nikon objectives. I still like it a lot, but if I had to choose just one of the two, I think I'd go with Edmund's Nikon Achromatic Finite Conjugate 10X NA 0.25 160/- as shown at your second link. The reason is a wider field that permits pushing down to lower magnifications by using less than 150 mm extension. But really it depends on what you want to do. If you want to start at 10X on the low end and push up with longer extensions, then the CF N Plan Achromat 10X NA 0.30 will give a little higher image quality. If you want more room to go lower, say down to 7X, then the Achromatic 10X NA 0.25 would be better.

You will not regret the purchase of any of these lenses.

By the way, all of my comments refer to using the objectives with a 1.6 crop factor sensor. On a full-frame 24x36mm sensor, you'll run into some coverage issues that affect the recommendations.

One thing I don't see in your list of equipment is any sort of small-step focusing mechanism. At 10X, you need focus steps around 10-15 microns (0.010-0.015 mm). That's much finer than you can get with an ordinary focus rail. There are a number of viable possibilities here, ranging from a StackShot automated rail (very nice!), to hand-turned screws on linear slides, to focus blocks salvaged from microscopes. For discussion, see FAQ: What's the best way to focus when stacking? and the links therein.

I hope this helps! Again, welcome aboard! :D

--Rik

luna
Posts: 4
Joined: Sun Jul 24, 2011 1:04 pm

Post by luna »

Thanks for the help! I'm actually shooting with a 5Dii, but I'm going to look into trading my 5D classic for a 7D to gain the 1.6 (I never thought I'd refer to a crop sensor as a plus!).

It looks like the Edmund's is the one for me right now. I did look at the .30 more than a few times, but I'd like to stay on the less expensive side if I can without sacrificing quality. I'd like to pick up a 20x and 40x when I get a better idea of what I'm looking for (any recommendations?).

I've got a StackShot with extended rail and arco in my shopping cart, but I've been waiting on a check for a few days to fund said purchase. :)

I appreciate the detailed response; understanding the differences helps tremendously.

rjlittlefield
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Post by rjlittlefield »

Edmund's sounds good. It may actually have enough coverage to do your 5D Mark II at 10X. In the worst case (according to calculation...) it should be only the corners that go soft. You can add some extension to increase the magnification, though this will rapidly eat into your limited working distance with that lens.

If you have a 1.4X TC in your bag, you might also try sticking that between the bellows and your camera, maintaining the same bellows setting that you would use to get 10X without the TC. This will crank up your magnification to 14X without changing the working distance, and might give you a better tradeoff between coverage and central quality. But I emphasize "might". I have no experience with that configuration, so this is all from theory.

--Rik

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