Meade TMB-130 specifications Collimation screws One pair of three

The collimation screws

(one pair of three)

The collimation screw	The lens cell
(taller)

aberrations, and 1/60th wave for sharp (fifth order) aber- rations. It is highly unlikely that even the most ardent ob- server can see errors of this small a magnitude, even under very good seeing conditions (which is when the atmosphere typically presents a 1/4th wave P-V wavefront to the tele-

TMB Optical TMB-130

Thomas M. Back Signature Series

The lock screw

(shorter)

Lens

the shorter of the pair is the lock screw that holds the proper collimation after adjustment. Be sure to adjust only one set of collimation screws at a time. Loosen the lock screws before attempting to turn the collimating screws. Make only small changes at a time (turning the collimating screw only a fraction of a turn and checking to see the results before turning further).

When you finish adjusting the collimating screws, be sure to snug down all lock screws to hold the correct colli-

scope and eye).

Something else to consider in star-testing refractors: the change in spherical aberration with a change in wave- length. This is called “spherochromatism” and is found in the wavefront of all refractors. What this means is that as the lens is tested in the longer (red) wavelengths, the lens becomes “under-corrected,” and in the shorter wavelengths (blue), the lens becomes “over-corrected.” These overlap- ping corrections at different wavelengths change the star test pattern from perfection.

So, while star tests are interesting and useful, most ob- servers spend their nights enjoying the heavens, not just examining points of light. We feel that the proof of optical excellence is in the observing, not just in the testing.

All TMB objectives are corrected at the peak visual wavelength, which is centered at around 560nm in the

Thank you and congratulations on your purchase of this TMB Optical TMB-130 130mm f/7 ED apochromatic triplet refractor. Its optical and mechanical quality will give you many years of observing enjoyment.

TELESCOPE MOUNTS

Your new TMB-130 is usable with many different types of telescope mounts. A suitably sturdy altazimuth mount is a good choice for most purely visual observing. An altazi- muth mount is typically light in weight, easy to set up, and is relatively low-priced. Just be sure that the mount is ca- pable of handling the scope’s weight (which will be well over 20 pounds after adding mounting rings, diagonal, eye- piece, etc.)

A high quality German equatorial mount would be an excellent choice for both visual and imaging purposes. The very stable German-type equatorial mount can be driven

medium format film cameras and very large chip CCD cameras. The drawtube ends in a 2” accessory adapter with a non-marring soft brass compression ring eyepiece holder that will not damage the barrels of your 2” eyepieces and accessories. This adapter allows visual use with 2” star diagonals and eyepieces, plus imaging with 35mm film cameras and 2” barrel large format CCD cameras.

The 2” accessory adapter is secured to the focuser draw- tube by three recessed hex-head screws. Undoing these allows you to remove the supplied 2” adapter and replace it with a custom-made Feather Touch adapter for medium format (Pentax 6 x 7) film photography using A-P photo- graphic accessories. Please contact Starlight Instruments directly at (847) 985-9595 for any specialized adapters you may need in this regard.

mation. Do not over-tighten the lock screws, but make sure they are firmly in place. Once collimation is complete, your objective lens will be on the same optical axis as the eye- piece, camera, or CCD, and you will obtain the best pos- sible optical performance.

The other method of collimation is to examine a first or second magnitude star image at high power at night af- ter the scope has reached thermal equilibrium. This colli- mation method requires an equatorially-mounted scope and a motor drive to keep the star image centered while you adjust the collimation screws. It is generally a more diffi- cult and time-consuming collimation method than using a Cheshire eyepiece, as you are working with a small and droppable Allen wrench in the dark and are at the mercy of changing seeing conditions.

Be sure not to choose a closely-spaced binary star as your test star. Do not use a star diagonal when collimating,

green-yellow portion of the visual spectrum. The eye sees over 80% of the visual detail at this wavelength, and it is the proper correction at this visual peak that makes the difference between just a good objective, and a superb one. We design and figure our lenses for the best possible wavefront at the green-yellow wavelengths, to give you the sharpest images and highest contrast possible.

A FINAL WORD

We thank you for your purchase of this TMB-130. We believe that this apochromatic refractor will outperform any other telescope type, inch for inch, and is the most trouble-free telescope that you can buy. Its versatility in visual, photographic, and CCD work is unmatched. With a little care, this fine apochromatic refractor will last you a lifetime. Please enjoy the wonders of the night sky!

TomBack

in both right ascension and declination for photography and CCD imaging, as well as for uninterrupted visual ob- serving. The quality of your images will not only depend on the optical quality of your telescope, but your local con- ditions (the seeing and how dark your site is), the tracking accuracy of your mount, your imaging equipment, and your guiding and image processing techniques.

TUBE RINGS

No tube mounting rings are supplied with your TMB refractor. However, well-machined 142mm TMB hinged split rings are available from your telescope dealer.

FOCUSER

Your TMB-130 has a dual speed Starlight Instruments Feather Touch Model FTF3545 rack-and-pinion focuser. This ultra-premium focuser has a long travel 3.5” diam- eter drawtube for non-vignetted astrophotography with

Focuser rotation handle (1 of 3)

Focuser

rotation angle locking ring

Coarse focus knob

Fine focus knob

as you may be attempting to correct a problem in the di- agonal, rather than in the telescope. Adjust the push-pull collimation screws until the star images are tight and round, and the first and second diffraction rings are uniform in their intensity all the way around the Airy disk.

THE STAR TEST

We strive to make the best apochromatic optical sys- tems available. You may find your lens may not test “per- fect” during an extended and stringently-graded “star test,” particularly if the scope has not fully reached thermal equi- librium before the test. This is not an indication of a poor optic. It is rather due to the test star’s complex wavefront of light that is being constantly changed by our living at- mosphere as seeing conditions vary from minute to minute, from second to second.

No optic is perfect and likewise, under a detailed and extended star test, every telescope optic will show some error. The sensitivity of the star test under perfect condi- tions is 1/20th wave P-V on the wavefront for third order

SOME BRIEF SPECIFICATIONS

Aperture			130mm (5.1”)
Focal Length			910mm
Focal Ratio			f/7
Objective Type		air-spaced ED triplet apochromatic
Optical coatings			fully multicoated
Resolving Power (Dawes’ Limit)			0.89 arc seconds
Visual Limiting Magnitude			13.1
Light Grasp Versus the Eye			345x
Focuser	FeatherTouch #FTF3545 rack and pinion

with dual-speed and 11:1 reduction ratio fine focus; 2” and 1.25” compression ring eyepiece holders; 360° rotating camera angle adjuster

Focuser Travel	4.33” (110mm)
Tube Diameter	142mm (5.6”) o. d.
Tube Length (lens shade retracted)	28.75” (730mm)
Tube Length (lens shade extended)	34.5” (876mm)
Optical Tube Weight	18.7 lbs. (8.5 kg)

Finder bracket	Focuser rotation
mounting holes	handle (1 of 3)
	Screws
	connecting
	2” adapter
	to drawtube
	(2 of 3)

2”	Brass
accessory
	compression
adapter
	rings

2” accessory

lock knob (1 of 2)

		Combined drawtube
		tension/lock knob
		under focuser
		Focusing scale
		on drawtube
		(1 on each side)
Brass	2” accessory	2” accessory
compression	adapter	lock knob
ring		(1 of 2)

Features of the Focuser’s Right Side

The supplied 2” to 1.25” accessory adapter is designed for visual use with 1.25” star diagonals and accessories, plus imaging with standard format CCD, webcam, and 35mm adapters. This adapter also uses a non-marring soft brass compression ring to hold your 1.25” star diagonals and accessories in place. The barrel of this adapter is threaded to accept standard 2” filters and has a slight in- ward taper at the top. The taper engages the compression

TMB Optical, P.O. Box 44331, Cleveland, OH 44144	(216) 524-1107
E-mail: TMBoptical@aol.com	© 2007 by TMB Optical

Coarse focus knob 1.25” accessory adapter

Features of the Focuser’s Left Side

ring of the 2” adapter to prevent the 1.25” adapter from slipping out of the focuser, should the 2” adapter’s thumb- screw accidentally loosen during use.