I gathered here a short description of equiment I use to observe or to photograph the sky. On other pages I will often refer to a this or that piece of equipment, and this is the place where you can find a few words about it.
At the moment, I am using Windows XP OS, with a great preference for freeware or gnu-licence programs. These pages are composed in a very simple html with the help of HomeSite 1.2, freeware version. For all kinds of digital image processing I really love to use IRIS, and to simply look at the images I use the excelent IrfanView. Beleive it or not, some basic operations on images I do in Microsoft PhotoEditor. Writing, calculating, etc. is job for the Office XP, without any intention to upgrade, and for serious writing (scientific, math, tables, etc.) I use exclusivelly Latex. If I need to program something, Dev-Pascal is the working horse.
Some other programs I use are Cartes du Ciel (Sky Charts in english translation), HN sky and Virtual Moon Atlas. I also use several very small freeware tols, that are tailored exactly to do what you need and nothing more. For instance, avi2bmp is excellent in extracting single frames from an avi movie.
When presenting results of lens testing, I will try to provide small parts of the image in full resolution of the camera, in my case either Canon EOS 300D (pixel size 7,35 mikro-meters) or Canon EOS 1000D (pixel size 5,7 mikro-meters).
|I am using color filters a lot. I gathered here transmitance curves of some of them as they are almoust impossible to find on the web. Maybe they will be of help to someone else too. I measured filter transmission curves on an old prismatic spectrograph of russian origin (model ISP 51), with my modified EOS 300D as the detector. I checked the precision, and it was a few percent in absolute value of the transmitance in the spectral interval between 500 and 1000 nm. Outside this region, esp. in the blue below 450 nm the tungsten filament lamp I use as the light source has not enough light to provide accurate measurements.The wavelength scale is acurrate to 1 nm, or better. Individual transmission curves are here.|
|This russian made telephoto lens was sold a part of the so caled photo-sniper. The complete included a sturdy case, this telephoto, a normal objective lens, a zenit camera body and a gun-like holder for the telephoto. I got mine sometime in 2007. on a local second-hand market, never used the zenit camera, and stored avay the normal lens (Helios 44-2 58 mm F/2) due to its quite low optical quality. As a contrast, the Tair-3S 300 mm F/4.5 telephoto is a very good telephoto lens, even coupled to a DSLR. More details about it are here.|
|EOS 300D was my first serious digital camera. It is modified and made sensitive to the complete visible and infra-red part of spectrum to which its detector is sensitive. In other words, its usuall IR-blocking filter is replaced by a piece of optical glass. More details about camera and first tests of several old M42 lenses with it are here.|
|Neodymium filter is a cheap alternative to interference filters designed to reduce light pollution. It is quite effective in reducing the light pollution produced with high-pressure sodium lamps, a kind of lamps that currently dominates my neighbourhood. I especially like the new Baader version which additionally blocks infrared light, imporant if one, like me, uses a modified, infrared sensitive, DSLR. More details about this filter are here.|
|Rubinar 500 is a russian-made telephoto lens for classical photography. I do have a certain preference for russian optics. It is alwas mechanically very solid, and optical qualitiy is usually good, smetimes even excellent. I need to warn you here. Some russian lenses are horrible. Those I encountered, I will describe briefly on these pages too, in hope others will read and learn before buying! I often learned after.... The optics of Rubinar-500 is of solid quality, although with modern digtal cameras, especially if pixels are smaller than about 10 micro-meters, binning may be necessary. One should always have on mind that very strict tollerances for classical photograpy required the stellar disc to be about 20 micro-meter in diameter. Long time ago I measured sizes of faint star images on my negatives, 30-40 micro-meters was the smallest I found. OK, a part of this size can be atributed to fast, grainy, films I used, but still, the digital photography simply puts strighter tollerances on lenses. Some test results of this lens are here.|