Digital UVA-photography with M43 equipment

How far can we go, with off-the-shelf equipment One question which I have been pondering for some time is: do I need to have a digital camera converted to full-spectrum for UVA photography? and are there any modern objectives that are good accidental UVA-objectives? This is not a question of cost alone. Although a converted camera can be used for VIS photography, obtaining good colour reproduction requires effort. A suitable filter is used on the objective to replace the one removed from the image sensor unit during conversion. As it is not possible to find a perfect match to the…

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How small can a UV-B plus UV-A sensor be made?

[updated 2019-02-13] [I will update this post again after testing the sensor] Rather recently Vishay announced a miniature sensor under the name VEML6075 with two channels nominally centred at 365 and 330 nm. The peak width at half maximum is 20 nm. So, in practice it is a sensor measuring two regions within the UV-A band with the tail of one of the two channels extending into the UV-B. It is not a sensor capable of separately measuring the UV-B and UV-A bands. However, under sunlight it collects enough information to obtain a reasonable estimate for the UV Index (see…

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More on taking photographs through windows

The “Ultimate Lens Hood” seems like a good tool. It is still to be seen if it is stiff enough and/or a bit sticky so as to easily stay in place on the glass surface. It has the potential for being very useful but how easy it will be to handle with different lenses is still to be seen. I just made my pledge for one ULH at Kickstarter. If you want to get your own, be aware that the campaign is about to end. See my earlier post to learn how I have been managing until now with normal…

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Aputure’s Amaran AL-M9 vs. Sunway Foto’s FL-96

LED sources

This gallery contains 4 photos.

Aputure’s Amaran AL-M9 and Sunway Foto’s FL-96 are very small and handy LED light sources. The Amaran AL-M9 has been relegated to a second place in Aputure’s catalogue by the Amaran AL-MX, but I haven’t bought this newer and three times as expensive version. Both light sources compared here are roughly within the same price range.

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Pinholes in NIR and UVA

Using the E-M1 converted to full spectrum with the Pinhole Pro objectives is possible. Using a 58 mm NIR filter (Hoya R72) attached to the front of the 11 mm Pinhole Pro S11 worked fine, with no increase in vignetting. Using the StraightEdgeU 52 mm or Baader U-filter 2″  with a step-down ring blocked the corners of the image completely. The original 26 mm Pinhole Pro suffers a lot less from vignetting and can be used with these filters of smaller diameter than the front thread of the lens without problem.

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Pinhole objectives arrived today

Introduction Pinholes need to be very small to provide a useful image. Consequently the corresponding f-values are small, in most cases f:100 or smaller. This results in either very long exposures, or requires the use of very high ISO values. As we will see in the example images this is less of a problem than what could be expected because as the resolution of the pinhole is low, the images tolerate very strong noise reduction processing without losing there character or mood.

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