ORION TELESCOPES & BINOCULARS 5302 User manual

INSTRUCTION MANUAL
IN 565 Rev. A 02/16
Orion Field Flattener for EON
104mm ED-X2 Triplet Refractor
#5302
The Orion Field Flattener for EON 104mm ED-X2 was designed exclusively for the EON 104
ED-X2 Triplet Apo Refractor, to flatten the focal plane for astro-imaging without affecting the focal
length of the telescope, even on full-frame camera sensors. For photography only, not visual use,
this high-performance 2" field flattener is highly recommended for obtaining the highest-quality
images with your EON 104.
This field flattener has an optimal backfocus distance of 55mm (distance from threaded attach-
ment plate to camera sensor). It comes with interchangeable, thread-on adapter plates, one with
42mm (T-mount) male threads, the other with wider, 48mm male threads (which are equivalent to
2" filter threads).
Figure 1. The Orion Field Flattener for EON 104mm ED-X2
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Copyright © 2016 Orion Telescopes & Binoculars
All Rights Reserved. No part of this product instruction or any of its contents may be reproduced,
copied, modified or adapted, without the prior written consent of Orion Telescopes & Binoculars.

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Attaching the Field Flattener to a DSLR Camera
The field flattener’s 55mm backfocus distance is designed to work with most DSLR cameras without the
need for any additional extension rings (Figure 2.1). A T-ring for the make and model of your camera
is the only required accessory to attach the field flattener to your DSLR camera. The ring can be either
a standard 42mm T-ring or a wide 48mm T-ring. The 48mm T-ring, when used with the 48mm adapter
plate of the field flattener, is ideal for use with full-frame camera sensors as it will reduce the possibility
of vignetting, giving you better illumination at the edges of the sensor
Attaching the Field Flattener to a CCD Camera
Most CCD cameras have a shorter flange focal distance – the distance from the camera’s lens mount-
ing flange to the focal plane, or sensor—than a DSLR camera. That means you will need to add exten-
sion as needed to fill the 55mm of required distance to the field flattener (Figure 2.2). T-thread exten-
sion rings, or spacers, of different lengths are available separately; you just need to calculate how much
extension is needed for your particular camera. Consult your camera’s manual to determine the flange
focal distance.
For example, if a camera has a flange focal distance of 20mm, i.e., its focal plane is 20mm behind the
lens mounting flange, you would need to add 35mm of space between the camera and field flattener
to achieve the proper distance (20 + 35 = 55mm). Note that if you do not reach 55mm exactly, the field
flattener will still work, but will gradually lose its effectiveness the farther in or out from 55mm your cam-
era is positioned.
Your CCD camera must have compatible 42mm or 48mm female T-threads on the camera body to
attach to the field flattener. Remove the camera’s nosepiece (if it’s equipped with one) and thread the
camera body directly onto the back of the field flattener or threaded spacer ring.
Care & Maintenance
Care should be exercised when using all optical and mechanical telescope accessories. Keep your
field flattener in a protected environment when you’re not using it, and place the dust cap and threaded
metal cap on the Field Flattener for storage. Avoid touching the lenses and coatings. If the outside of
the lens should become dirty, you may want to clean it. Remove loose dirt with a blower bulb or lens
brush. Use only optical lens tissue and good-quality lens fluid. Wet a folded tissue and gently wipe the
surface of the lens. Immediately use a second piece of lens tissue to gently dry the lens off. Do not rub
or apply pressure, as this may scratch the lens if dust or grit is present.
Specifications
Optics 2-element, fully-multicoated
Clear Aperture 50mm
Focal Length 55mm
Mechanical Length 50.2mm
Barrel: 2", tapered neck, threaded for 2" filters
Weight 8.3 oz (23.4g)
Adapter plate threads: 42x0.75mm “T-thread” (male)
48x0.75mm (male)

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Field
Flattener
DSLR
camera body
T-ring Adapter
plate
(42mm
or
48mm)
(42mm
or
48mm)
2" collar on telescope
Figure 2.1. Using the field flattener with a DSLR camera.
Field
Flattener
CCD
Camera
55mm
Xmm
Distance from CCD
chip to Field
Flattener T-threads
should be 55mm
“X”mm of additional spacing may
be required to achieve 55mm,
depending on make and model
of camera.
2" collar on telescope
Adapter
plate
(42mm
or
48mm)
Figure 2.2. Using the field flattener with a CCD camera.

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One-Year Limited Warranty
This Orion product is warranted against defects in materials or workmanship for a
period of one year from the date of purchase. This warranty is for the benefit of the
original retail purchaser only. During this warranty period Orion Telescopes & Binoculars
will repair or replace, at Orion’s option, any warranted instrument that proves to be
defective, provided it is returned postage paid. Proof of purchase (such as a copy of
the original receipt) is required. This warranty is only valid in the country of purchase.
This warranty does not apply if, in Orion’s judgment, the instrument has been abused,
mishandled, or modified, nor does it apply to normal wear and tear. This warranty gives
you specific legal rights. It is not intended to remove or restrict your other legal rights
under applicable local consumer law; your state or national statutory consumer rights
governing the sale of consumer goods remain fully applicable.
For further warranty information, please visit www.OrionTelescopes.com/warranty.