12" F/4 Newtonian on Fornax 51 mount
Made in 2008 at home. Tube was made of carbon fibre material, which is temperature stable and very-very rigid. Tuberings are made of wood (!), and there are also home made holders for the mirrors. Primary is from Orion England (Professional grade, 97% Hilux coating), secondary (4") is from Antares, Canada. Both are very good quality. To correct coma first I used TeleVue Paracorr Type-I, which was very sharp on axis, and corrected coma perfectly of the F/4 mirror within the 28mm image circle. At the same time it multiplied the focal length of the telescope by 1.15, so the effective FL was around 1370mm and it gave F/4.6 focal ratio.
In 2009 this
telescope has been upgraded with
a self designed 3" Crayford focuser, specially made for accepting a 3"
Wynne coma corrector. This corrector perfectly corrects coma within
a large 50mm image circle, making possible to image with large full
frame (24x36mm) sensors like the Canon EOS 5DmkII. It has a reduction factor of 0.95, so the
effective FL is being shortened to 1130mm, giving a focal ratio of F/3.8.
300/1200 Newton gallery
51 is a good mount, it has a great value for the money. It has no backlash, and reacts
immediately to guiding corrections on both axes. Tracking is very
smooth, periodic error is also in a smooth +/- 5" range.
Head weights 28kgs (62lbs), load capacity is up to 50kgs (110lbs).
Fornax 51 gallery
8" F/3.75 Newtonian - astrograph
12" telescope building project was successful, I built a smaller
"brother" in 2009, based
on similar solutions, for wider
field imaging and for traveling. The carbon fibre tube is a new generation model, it looks much better than the larger 300mm tube. it is also lighter, while mechanically
is the same (rigidity, temperatue stabilization). Mirror holders were machined with CNC, so they are more precise and looks nicer than the previous ones. Both primary and secondary (3.5")
mirrors are from
Optics England, enhanced with 97% Hilux coating. This telescope
has also been equipped with a new 3" Crayford focuser (my own design),
specially made for accepting the 3" Wynne coma corrector. This
corrector perfectly corrects coma within a large 50mm image circle,
making possible to image with large full frame (24x36mm) sensors like the Canon EOS 5DmkII.
It has a reduction factor of 0.95, so the effective FL is being shortened
to 710mm, giving a focal ratio of F/3.55.
I made some modification on the tube in 2014. The classic wooden tube rings has
been replaced by a fixed metal ones (see image on the right), so now the scope is lighter and
less counterweight is needed to balance it (especially good for traveling). This telescope can
be used with both EQ6 and Fornax mounts. Fornax
holds it rock solid, so imaging on windy nights are also possible.
200/750 Newton gallery
The mount EQ6 is a basic model from 2003. It has been modified in 2007, a belt drive system has been built into the mount. It is controlled by the compact and reliable Dynostar X3 GOTO controller from Boxdörfer, Germany. The system gives very smooth tracking despite the relatively big overall periodic error, which is around +/-15". Autoguiding is easy with both Lacerta-MGen stand alone autoguider or the old ST-4 (sold), tracking performance can be sub arc sec on steady nights.
130/780 TMB apochromat
It was my main imaging telescope between 2003 and 2009. It has a custom made tube
with the gorgeous TMB 130/780
triplet apo lens inside. I use the original TMB giant
which gives pinpoint stars to the very edge of the full
format (36mm) sensor of the 5DmkII. It
is not surprise, because this FF developed to cover medium
have been used succesfully between 2003 and 2006. At this time this telescope is rarely used for imaging, because of the slower
F/ratio and less light gathering power compared to the fast and larger aperture astrographs.
130/780 TMB gallery
150/900 Intes Maksutov-Newtonian
It was my main astro gear between 1999-2003. I used it for multiple purposes; Moon, planets, double star and deep sky observing, including film astrophotography. The optic was made by Intes, tube was a home made one. The mount was a Gemini G10 with dual motor drive and built-in polar scope, allowing manual guiding. The optic of the scope was great, with only 20% central obstruction the image quality was close to the apochromatic refractors. It was possible to push the magnification up to 400x with no image breakdown on steady nights. It has been sold just before buying the TMB lens.