The Svbony SV555 f4.5 APO tube is a very high quality lens at a surprisingly affordable price. It is safe to say that what can be got out of a 54 mm diameter 243 mm focal length apochromatic telescope with an aperture of f/4.5 has been achieved.
The 243 mm focus makes this ultra-portable instrument ideal for wide-field deep-end photography. The SV555's bright f/4.5 Petzval-style apochromatic optics feature 3 groups of 5 lenses, two of which are made of low-dispersion (ED) glass material. The effect of the ED lenses is to almost completely eliminate the image-distorting effect of chromatic aberration, which is typical of high-intensity refractors. Naturally, all lenses have a FMC anti-reflective coating, which not only protects against harmful flare but also maximises the lens' light-absorbing power.
The lens is capable of "drawing" a 44 mm round, making it perfect for use not only with APS-C cameras but also with Full-Frame (36 x 24 mm) sensor cameras.
In addition to astrophotography, the Svbony SV555 f4.5 APO tube was designed with the needs of nature photographers in mind. For example, it has incorporated an unusual variable aperture (light aperture, stop) (f/4-5 to f/22), which allows the amount of incoming light to be varied freely and also gives a wide range of flexibility in the choice of depth of field. The aperture, which has a rounded shape all the way round, creates a beautiful bukeh effect, meaning that the lifeless light spots in nature photographs have a nice regular circular shape.
Typically for daytime use, 72mm filters can be placed on the front of the lens. For astrophotography, 2" (M48) filters can be placed at the end of the shutter, but of course you can optionally use a filter holder drawer or filter changer.
With the curtain rotatable 360°, we can choose the right composition without any obstacles. The helical gimbal with internal focus adjustment is highly adjustable, which can be increased by purchasing an EAF . The necessary accessories for fitting the EAF are also included in the package.
The telescope can be mounted on the mechanism with a tube ring and prismatic rail. It is compatible with both Vixen and Arca-Swiss clamping systems. (Arca-Swiss is a quick-change camera tripod system.) Carrying the scope is made easy with a handle with a guide scope holder.
The tube ring also has holes prepared to accept Svbony finder scope mount slippers.
