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View Full Version : Does anyone use a Mitakon Zhongyi 20mm f/2 4.5x lens?



Liney
21-12-2018, 3:52pm
I've been looking at adding to my lens collection and while I have a couple which are "normal" lenses with a macro capability, I was wondering whether to look at a dedicated Macro lens. I found reference to the Mitakon Zhongyi 20mm f/2 lens which offers a 4.5 times magnification, and wondered if anyone else has seen or used one.

Obviously at that level of magnification you need a tripod or focus rail, lots of light and it will give you a very shallow depth of field, but for super macro (or micro) images you almost expect that sort of thing.

Any comments?

arthurking83
25-12-2018, 9:19am
....

Obviously at that level of magnification you need a tripod or focus rail, lots of light and it will give you a very shallow depth of field, but for super macro (or micro) images you almost expect that sort of thing.

Any comments?

I've had a quick go with high mag macro .. and you don't just need a tripod .. you need a real tripod(if you're serious about IQ).
Nice big strong, sturdy, heavy, solid lump of a tripod!

So far(just for experimenting) I used my Nikkor 24/2 with a bellows unit(PB-4) to get distance between the lens and the camera.
ps. I was warned that IQ wasn't ever going to be as good as a dedicated lens designed for high magnification imagery, and they were right(with this lens at least) .. but I thought for helping with focus, I just wanted a nice bright lens to start with.

The issue for this type of photography is the working distance.
Sturdy tripod, and using a lens capable of resolving detail with clarity .. is one thing, and you could get everything to align perfectly in that sense, but at high magnification the issue you can't escape is working distance.
It'd be interesting to try one as a reasonably cheap price(est about $250-300 AU), but I've been trying to source a better solution to high magnification.(have some searches on ebay, and regularly check other sites if and when a lens comes up at the right price).

The alternative solution is: look for a microscope objective (ie. objective = lens, but they're all marked as 'objective' if you try a search). You can get various focal lengths, and prices vary from $100, to (max I've yet seen) $10's thousands.
The one I keep a look out for is roughly $1K. 19mm but it is a long working distance variant of a normal micro scope lens. These things all have various markings on them, (if you try a search) and the important one is LWD(long working distance).

If you don't care about working distance, your subject(the in focus part) will be basically up against the front lens element!
The obvious point there is if you want to work with live insects or whatever. MFD(which would be 4x magnifcation) is 20mm, or 2cm! .. so .. err yeah.

You obviously know what the lens is, so if you look closely at it's design, you'll notice it's like a 'small lens on a larger lens' design type. The small lens part(out front) is basically a microscope objective. These things are tiny, and they get mounted to a body(adapter/tube/extension/housing/rings/etc) that mounts to the camera body.

If you can get enough light to subject, tripod won't be so important ... you'd need some lights, and bump ISO up to maintain shutter speed.
With your Pentax system, you have plenty of choices of cheap adapters to work with, if you search for info on the microscope objective route ... I reckon about $20-50 for adapters, depending on what you'd prefer. The higher end(bellows) would be the best way for that.
Static extenders/tubes work, but are a pain.

The other option for high magnification stuff(2x) is the Laowa 24mm f/14 prove lens .. but this one is going to cost a lot more(apparently) over $1K.

If you want more info about microscope lenses, just holler, I have a bit of info that could help.

Now! .. if I could get some help to free me up some time, so I can get back to doing some photography, I could(possibly) get around to doing some of this stuff too.