Περιγραφή
Starizona EvoFF v3 Field Planner for SW EvoGuide 50ED
Starizona EvoFF v3 Field Planner for SW EvoGuide 50ED
The field flattener is optimized for astrophotography with astrocameras and system cameras (both mirrorless and DSLR) via the Evoguide 50ED; other compact refractors and scopes also benefit. These compact telescopes have a very curved field of view. As a result, off-center stars are distorted into streaks and the image becomes blurred. The EvoFF corrects this error and enables very good wide-field astrophotography. With a ZWO-ASI camera with an APS-C sensor, the field of view is approximately 5.5°x3.7°!
Comparison with/without EVOFF (predecessor)
The two test images were taken with a ZWO ASI294 astrocamera with a 23.2 mm diagonal sensor. The imaging telescope was a Skywatcher EvoGuide 50ED refractor.
On the left, you can see the result without the EvoFF corrector. The stars are distorted into sharp lines.
On the right, the result with EvoFF. The stars are sharp across the entire image field.
Which cameras is the EvoFF v3 suitable for?
The working distance of the field flattener on the Evoguide 50ED is 55mm from the T2 thread, making this new version’s corrector also suitable for DSLR cameras. For use with refractors with longer focal lengths, the distance would need to be reduced.
Which telescopes is the EvoFF v3 suitable for?
The corrector was developed for the Evoguide 50ED, but it can also be used on other small, fast refractors with focal lengths between 240 mm and 450 mm. The corrector connects via the 1.25″ barrel.
The refractor must have sufficient backfocus, which is achieved with the Skywatcher EvoGuide 50ED after unscrewing the 40mm extension tube.
The T2 rings, T2 extension tubes, and tuning rings required for your camera are linked in the accessories section.
Astrophotography with the Skywatcher EvoGuide 50ED :
The Skywatcher EvoGuide 50ED has a double ED lens with a 50mm aperture and a fast f/4.8 aperture. The scope offers a good helical focuser and a 1.25″ receptacle. This allows you to attach the corrector directly to the telescope.
The working distance from the EvoFF’s T2 thread is 55mm, so you can attach a DSLR or mirrorless system camera directly via a T2 ring and have the correct distance.
For a cooled ZWO camera with a 17.5mm flange focal length, you will need the 21mm T2 spacer ring, T2-M48 adapter, and T2-M48 16.5mm adapter ring, all included with the camera.
TECHNICAL SPECIFICATIONS :
- Optics: 2-element design
- Coating: Multi-coating on all air-glass surfaces
- Telescope side connection: 1.25″ tube with filter thread
- Camera side connection: Male thread T2 (M42x0.75)
- Field of view: 28 mm illuminated and corrected
- Weight: less than 100 grams
Starizona EvoFF v3 Field Planner for SW EvoGuide 50ED
