A lot of snow.

My way to work

This weekend I took the time to compare the results of macro photos achieved with a real 1:1 macro lens (a AF Micro Nikkor 105mm f/2.8), my father in law bought last week at the camera bourse and the kit lense Nikkor AF-S DX VR 18-55 1:3,5-5,6G with a +10 close up lens, which I bought there, too. I used my Nikon D90, a tripod and a normal indoor floor lamp. I did not use any flash or special illumination technique.

The Subjects: I used three flowers as subject, a cyclamen (Alpenveilchen), an amaryllis and an orchid.

The AF Micro Nikkor 105mm f/2.8: This lense is a few years old, don’t know how many, but it was built for 35mm film and not for DX cameras. But it works great with the D90, including the autofocus and automatic. Formerly this is a f/2.8 - 32 lens, but this depends on the focus. The range is huge, so this may become f/5 - 57 dependent on how near the focused subject is. This lense is the predecessor of the AF-S VR Micro-Nikkor 105mm f/2.8G IF-ED and it is supposed to do a 1:1 image.

AF Micro Nikkor 105mm results

I added the f numbers to the file name so that you can compare the depth of field, too.

The +10 close up filter: Having in mind that the +10 close up filter costs about 10 or 20 EUR and the macro lens about 400, the results in conjunction with the Nikkor 18-55 are really great. Of course you have to got much closer as the focal length is shorter. But you almost get a 1:1 of the subject.

+10 close up filter results

I used different f stops here to be able to compare the depth of field with the macro lens results, too.

Conclusion: To be honest, I don’t see so much difference between the images taken with the macro lens and the images taken with the close up filter. There is a bit of difference, the close up filter produces more color fringes in the out of focus edges than the macro does. And the macro lens of course does have more advantages: You can keep a distance of about 10-20cm, with the close up filter in front of the 55mm lens you have to get really close: a few centimeters. And, of course, you can use the macro lens for landscape photography or, even better, as a fast and good portrait lens. You don’t have to screw a filter on and off if you get closer.

The Bokeh of the close up filter is unexpectedly nice, I think. There is not much difference in comparison with the macro lens. I really would like to hear about your opinions regarding macro photography using standard lenses with powerful close up filters.

The maximum depth of field of the macro lens using the minimal aperture seems to be slightly deeper than the depth of field which can be achieved by the normal lens with the close up filter. This can be a reason to use a macro lens.

Finally: Casually I noticed that the diameter of the macro lens is the same than the 18-55 lens and I tried to put the close up filter in front of the macro. You can — well, you have to — get really, really close (about 1 cm), having a focal length of 105mm and I think this is quite more than 100% of the real subject!

Macro lens with close up filter

Those photos are not cropped, just resized. The depth of field is so small that I had to close the aperture as much as possible to get at least one or two millimeters of focus. The real size of the stamina of the amaryllis is about 5mm. Quite impressive.

More: I did not try any extension tube yet. But what I really want to try one day is a retro adapter (or reverse adapter).

I wrote about this earlier. And I wondered if the correction made by the internal software of the Nikon D90 while converting to JPG has to do with the lens you use and if it has to be a Nikkor lens to get those results.

The corrections consist mainly in two actions: reducing the chromatic abberation and correcting lens distortion. And both of them are applied with my 14mm Sigma lens (which is quite a few years old and built for 35mm film cameras). I don’t know if the distortion correction comes from a database and/or from heuristic values, but I am quite sure that the chromatic abberation is corrected automatically — at least the lateral chromatic abberation. Although this article is about the Nikon D3x I believe that the technology mentioned in this paragraph applies to the D90 (and probably all other cameras labeled with “Expeed”), too:

[…] The lateral chromatic aberration correction will work with any lens, including those not from Nikon, because the correction applied is based on an analysis of the image data, not on lens information. If shooting NEF, the correction isn’t applied to the RAW data, but information about the analysis is, …

Chromatic Abberation in JPG produced with UFRaw, JPG produced by the Camera (100% crop)

This is a part of a photo shot with the D90 in RAW+JPG mode with the Sigma 14mm/2.8 lens mounted. The version without chromatic abberation is the JPG produced in the camera. The other one is produced by UFRaw without lens corrections.

You’ll know it, and if not, you’ll know it right now. It really matters how you convert a three channel color photo (RGB) to black and white.

I shot this one this morning on my way to work with the new 14mm Sigma lense. The sky was a little bit red toned, with bluish cloud stripes. So the only way to get details in the sky without reducing the global contrast I want here, is to exaggerate the red channel and lower the blue and green channels. So I get the subtle differences in the sky out.

I used the channel mixer from UFRaw to convert this RAW file twice with different settings. The first one is just desaturated. The second one is the result of tuned channel mixing. As a side effect the red trailer and the red hubs of the tractor
turns bright (what is fine) and the blueish damp — bluish because of the blueish dawn light — disappears a bit (what is not what I intended). So If I would present this photo somewhere I probably would combine both images or do some selective adjustments in a way to get the damp of the desaturated image into the channel mixed.

There are tons of tutorials out there targeting black and white conversion including channel mixing and other methods. There is a one from Adobe, from Cambridge in Colour and one especially for Gimp.

Of course, especially in this case, if you exaggerate the red channel, you’ll run easily in difficulties with noise and broken gradients. This is because in daylight the sensor of a DSLR typically captures relatively a lot of green, some blue and a very little amount of red tones. And stretching the red channel over the whole tone range like I did here leads to gaps in the histogram.

This is explained in this libraw article, including a possible workaround. Very interesting.

Old Kodak camera (taken with the Sigma 14mm lens)

On sunday we went to a camera bourse in Frankfurt. It was fun, fascinating and interesting. A lot of old stuff, partly usable, partly unusable, partly interesting, a lot of lenses, used analog and digital cameras, filters, strange equipment, books, old magazines and so on. I think the oldest “camera equipment” were some Laterna Magica and glass plate “cameras” with the appearance of a wooden box.

We bought some protection filter for our lenses and a +10 close up filter for the Nikkor AF-S DX VR 18-55 1:3,5-5,6G, which can be used this way as a poor man’s macro lens and it works fine. I tried close up filter (+2, +3 and +4) with my 18-200mm zoom lens last year but — as I read in a review — the results are interesting because of the soft blurriness, but not comparable with real macro shots. This orchid is slightly motion blurred, I did use a tripod but not a remote control to release the shutter and it was just to get an impression what can be done with this +10 close up filter. The colorful structure of this flower is not much bigger than 1 cm.

Sigma 14mm 2.8D HSM

But the highlight was this Sigma 14mm f/2.8 wide angle lens. I really like wide angle photographs. And I miss it as the 18mm of my zoom lens results in effective 27mm because of the Nikon DX crop factor. The lens looks great and feels great, it is built of metal and really heavy glass. There is notable chromatic abberation at the outer areas using lower f-stops but the sharpness is great. The distortion is not extreme (I don’t want a fish eye effect). And you can get really close to a subject with this lens. Up to a few centimeters.

Wide angle landscape on my way to work (taken with the Sigma 14mm lens)

Finally. Bibble Labs released, as promised (I wrote about it before), a preview of Bibble 5!

I have not much time, but I gave it a short try. It looks great. Nice, smooth user interface, although I have to get used to it, runs fine under Linux and Windows. The preview is not full featured, there are features that are disabled and will be included in later Previews and in the final release — who knows when this will be…

The selective editing with a kind of layers is one of the features I am looking forward to. Great. I will write about my experiences with Bibble 5 here the next days and weeks. It seems that there are a lot of issues still open in this preview.