photo sharing and upload picture albums photo forums search pictures popular photos photography help login
Samir Kharusi | all galleries >> Galleries >> C14 Hyperstar - Initial Tests > Tight & Compact
previous | next
October 2009 Samir Kharusi

Tight & Compact

Azaiba, Muscat, Oman

In mid 2009 I acquired a new DSLR for astro use, a Canon 500D (or (T1i). This was modded by Hutech to end up with clear glass over the sensor, allowing use for spectroscopy, landscapes, HD videos, planetary videos, etc., from around 390nm at the Violet end to 1000nm at the Near IR end. It is also very light (great if you wish to add accessories when in Hyperstar use) and has tiny pixels, a 4.7 micron pixel pitch yielding 1.4 arc-sec per pixel with a C14 Hyperstar. It also has a whopping 15 megapixels, great for A3-sized prints from the Hyperstar.

The above shows my current set-up on a C14, going upwards from the OTA. Since the camera body is quite small, I decided to circularise its shadow by adding a small donut mask using black paper. The size required is 6" outer diameter with a 4.5" hole. Light loss is actually very minimal compared to the camera body on its own. The remaining annulus still gathers photons at 4.4x the rate that a 6" APO can. No more diffraction spikes. Next slide shows an example image. Instead of the Canon TC-80N3 Timer-Controller I got an Aputure clone, already with a plug for the 500D. Note that the plug is a right-angle one and consequently great for tucking things in tight. A rubber band is very adequate to hold it securely. At the top I have a right angle LCD periscope/porroprism, another Aputure clever gadget. This allows you to adjust camera settings conveniently. Very convenient for LiveView collimating the Hyperstar. I was hoping to be able to also focus the C14 with it. Unfortunately my arms are not long enough, so I still have to use a laptop for focusing :-( C11 users may be able to skip a laptop altogether. Of course, with the latest T3i and its swivel LCD screen, the periscope would be redundant.

Aputure products can be ordered, quite inexpensively, from: When placing your order there also include extra batteries for your camera. Their very cheap batteries seem to be as good as the Canon ones that cost much more.

Canon G10

other sizes: small medium large original auto
comment | share
lusia 29-Apr-2010 04:32
looks good