Achromatic macro filters

[Brad Bohland]

I just bought a Panasonic FZ1000 and want closer macro shots so I'm thinking about achromatic macro filters. Are they interchangeable, because Panasonic doesn't make a 62mm thread macro for the FZ1000. Would a Nikon or Olympus filter work?

Also, my Nikon P7700 has pretty bad chromatic aberration (especially with macro shots) and I'm wondering if I put an achromatic macro filter on it whether it would correct the native aberration on the P7700.

 

[steephill]

In the same order as your questions
--
Steve

www.pbase.com/steephill

 

[Brad Bohland]

Apparently these filters are rated by zoom range, for instance 50-200mm. The FZ1000 has a 25mm starting point. Is that going to make a difference at 25mm?

 

[darklamp]

I have a Canon 250D close-up filter of the Achromat design. In principle it's designed for short focal lengths ( can't recall exactly, but say below 100mm ). In practice it's fine on longer focal lengths.

I've used it on any lens it fits on either directly or with step-up rings. I've also used in on a bridge camera with a 28-300mm equivalent lens.

Canon make a 500D as well ( not to be confused with the camera of the same designation - silly Canon marketing people ) which is for longer focal lengths.

 

[AlbertTheLazy]

Apparently these filters are rated by zoom range, for instance 50-200mm. The FZ1000 has a 25mm starting point. Is that going to make a difference at 25mm?

Just zoom in a bit.

 

[Brad Bohland]

Which degrades an image more, magnification (macro filters) or cropping?

 

[AlbertTheLazy]

Which degrades an image more, magnification (macro filters) or cropping?

With good quality achromatic close up lenses (please don't call them 'macro filters') you will have hardly any image degradation compared to heavy cropping.

This is an ordinary house fly, about 6mm (1/4") long, shot using a Raynox 250 and uncropped. Using a typical general purpose lens you would have to crop a lot to get the image the same size on the screen.

--
Albert
Every photograph is an abstraction from reality.
Most people are more interested in the picture than the image.

 

[Brad Bohland]

Thanks. BTW, did you know that Alfred Hitchcock supposedly defined drama as ordinary life with the boring parts left out--kind of like good photography.

 

[Donald B]

I just bought a Panasonic FZ1000 and want closer macro shots so I'm thinking about achromatic macro filters. Are they interchangeable, because Panasonic doesn't make a 62mm thread macro for the FZ1000. Would a Nikon or Olympus filter work?

Also, my Nikon P7700 has pretty bad chromatic aberration (especially with macro shots) and I'm wondering if I put an achromatic macro filter on it whether it would correct the native aberration on the P7700.

heres what they can do. canon 500d fz150 hope this helps

cheers don





























































--
Pentax k7,fz150,xz1 my toys.

 

[Brad Bohland]

I just ordered a Raynox 150 and am looking forward to seeing what it can do. I'll return with a photo or two if I like it.

 

[bmw44]

I just bought a Panasonic FZ1000 and want closer macro shots so I'm thinking about achromatic macro filters. Are they interchangeable, because Panasonic doesn't make a 62mm thread macro for the FZ1000. Would a Nikon or Olympus filter work?

Also, my Nikon P7700 has pretty bad chromatic aberration (especially with macro shots) and I'm wondering if I put an achromatic macro filter on it whether it would correct the native aberration on the P7700.

The Olympus MCON-35 is a very high quality macro lens. If I remember correctly it is +3 diopters, so it will focus at just over 1 foot when your camera is set to infinity. I found the lens listed on ebay and amazon for about $50 used. Seems a bit high. I have one and maybe I should consider selling it since I seldom use it.

 

[_sem_]

Also, my Nikon P7700 has pretty bad chromatic aberration (especially with macro shots) and I'm wondering if I put an achromatic macro filter on it whether it would correct the native aberration on the P7700.

Closeup "filters" are most effective in the telephoto range of the lens. You don't even have to use close focus with them; the focus ring has a relatively limited effect; you mainly first choose the diopter strength, then adjust the zoom position (the longer, the more magnification). So the aberration situation is likely to be quite different.

The results also look different at the same magnification because the resulting effective focal length is not the same. The native macro mode magnifies most at wide-angle, while a suitable diopter on a long zoom position producing the same magnification mimicks a midrange-macro lens. The differences are in the longer working distance and in the stronger relative blur of the background.

What apertures does the macro mode pick? If near wide-open, the results might improve by stopping down. If there is not enough light for this, you can consider using diffused flash. Certain types of chromatic aberrations may also be suppressed digitally in post-processing.

 

[Brad Bohland]

I'm sure it will require some experimentation, but it's helpful to know that I might need to zoom in a bit to get the best effect.

I have Elements 9 which does not make it easy to fix chromatic aberration (CA). I don't know why these cameras don't have automatic correction (like red-eye correction) for CA. Heck, my Nikon P7700 even has a menu correction for barrel distortion, but it does not correct for pretty bad CA as you can see below.

 

[_sem_]

I'm sure it will require some experimentation, but it's helpful to know that I might need to zoom in a bit to get the best effect.

I have Elements 9 which does not make it easy to fix chromatic aberration (CA). I don't know why these cameras don't have automatic correction (like red-eye correction) for CA. Heck, my Nikon P7700 even has a menu correction for barrel distortion, but it does not correct for pretty bad CA as you can see below.

There are several types of CA. I guess your camera corrects lateral CA, which you can check by taking a good look at a raw file of a well-exposed flat target (like money or mm grid paper) converted with RawTherapee or some other converter which doesn't correct laCA by default. Other types of CA are more difficult or impossible to fix. Certain in-focus and non-blown parts look okay.

I think you've got blown highlights in your image. Autoexposure often fails with scenes that contain intense reds or blues. You should reduce exposure, and fill in the shadows in post if the image will look too dark. And shoot raw if you have scenes with such high dynamic range, so that you get better chance of recovering highlights and shadows.

 

[Brad Bohland]

OK, thanks. When you view the original size, though, you can see how bad the purple fringing is can't you?

 

[_sem_]

OK, thanks. When you view the original size, though, you can see how bad the purple fringing is can't you?

Well it ain't pretty, but this is not just typical purple fringing. You've got badly blown highlights, particularly blues, which makes things much worse. And F/2 is wide-open, where the aberrations are worst and depth-of-field the thinnest, therefore not best choice for macro. Remember the availability of such wide apertures is a relatively recent thing, and this doesn't come without side effects, otherwise DSLR kit lenses would all follow suit. Compact cameras are not designed for best macro results these days, but you can do better than this. I don't know why many cameras on auto tend to shoot closeups like this even when a wide aperture is not really required.

Notice there are no really wide-angle (like this) macro lenses for DSLRs either, that would produce aberration-free images. One can make similar images using a DSLR kit lens @wide-angle using a relatively short extension tube, but the quality is quite comaparable.

 

[Joseph S Wisniewski]

I have a Canon 250D close-up filter of the Achromat design. In principle it's designed for short focal lengths ( can't recall exactly, but say below 100mm ). In practice it's fine on longer focal lengths.

The rule of thumb is that when you close-couple two optical systems, the shorter lens dominates the image characteristics. The 250D is a 250mm lens (that's what the 250 stands for). So, when you put it together with a 100mm lens, that 100mm "contributes" over 2/3 the image quality and the 250mm contributes less than 1/3, so the overall image quality is similar to the 100mm, which is probably either a prime with at least 6 elements, or a zoom with at least 15.

Use the 250mm with a 300mm lens, and over half the image quality is being controlled by a simple 2 element achromat. You get a very "primitive" image quality that harkens back over 100 years.

I've used it on any lens it fits on either directly or with step-up rings. I've also used in on a bridge camera with a 28-300mm equivalent lens.

Canon make a 500D as well ( not to be confused with the camera of the same designation - silly Canon marketing people ) which is for longer focal lengths.

For exactly the reasons I outlined above.

 

[darklamp]

I can't say I ever heard of the reason why Canon named them as they did ( still poor choices given the cameras have similar names ). You're a mine of information as usual Joseph.

Use the 250mm with a 300mm lens, and over half the image quality is being controlled by a simple 2 element achromat. You get a very "primitive" image quality that harkens back over 100 years.

I have done this and I think "primitive" is a over-doing it. It's not optimal, certainly, but it's quite good in practice.

I think people used to high quality macro lenses on DSLRs tend to get a bit OTT about image quality, when many people regard it as "good enough" and probably would not even notice the issues.

 

[Brad Bohland]

Would f2.8 be acceptable?

 

[_sem_]

Would f2.8 be acceptable?

I'd go a bit further. Your sample could use some more DoF. But at F/8, you'd get very obvious diffraction softening.