Extension Tube
Would an extension tube make an erecting prism work on a newtonian?
Since the reason why erecting prisms or diagonals won’t work on newtonian reflectors is because of the lack of back focus, would an extension tube solve this problem?
And the only purpose of the erecting device on the newtonian is for daytime terrestrial viewing.
!ako
No. Where would you put the extension tube? Between the eye lens and ?
Easy to correct the inverted image–put the eyepiece tube on the top of the main tube of the newtonian, then turn your back on the subject, and view in the eye lens.
The image is now upright.
|
|
Blue Fireball 2″ 80mm / 3.15″ Eyepiece Extension Tube for Telescope # X-05 $30.50 |
|
|
New Macro Extension Tube Set for Pentax K/PK mount $9.73 |
|
|
Olympus Auto 7, 14 & 25 Extension Tube Set $50.00 |
|
|
Macro Close Up Extension Tube Ring fits Sony A500 A330 $13.99 |
|
|
NEW CANON EXTENSION TUBE EF25 EF 25 MK II MKII EF25II $135.00 |
|
|
Macro Extension Tube w/ Cover for Canon 4 EOS DSLR SLR $12.19 |
|
|
NIKON F/F2 EXTENSION TUBE PK 3 27.5 CLOSE UP MICRO $47.49 |
|
|
Kipon Zoom Extension Tube for Pentax 67 645 HASSELBLAD $215.00 |
|
|
Auto Focus Macro Extension Tube for CANON EOS SLR EF EF-S L9A Camera New $50.92 |
|
|
Metal Mount Auto Focus AF Macro Extension Tube/Ring For Canon EOS 550D 600D 5D $74.45 |
|
|
Macro Extension Tube w/ Cover for Canon 4 EOS DSLR SLR $15.98 |
|
|
Auto Focus Macro Extension Tube for CANON EOS SLR EF EF-S L9A Camera New $50.93 |
|
|
Cap+Black AF Auto Focus ABS Macro Extension Tube Set For Nikon SLR Cameras L8E $57.89 |
|
|
Black Auto-Focus Macro Extension Tube for Canon Camera L9B $74.45 |
|
|
Black ABS Auto-Focus Macro Extension Tube Set for Sony SLR Camera L9C $69.49 |
|
|
Black Auto Focus Macro Extension Tube Set 13/21/ 31 Canon SLR Camera New L9A $30.95 |
|
|
AF Auto-Focus Macro Extension Tube Set 13/21/31 for Canon EOS SLR Camera L9A-US $55.26 |
|
|
3 Ring Auto Focus AF Macro Extension Tube Set for CANON EOS METAL MOUNT VERSION $109.99 |
|
|
Zeikos Macro Extension Tube Canon Rebel XSi XS T1i T2i $77.95 |
|
|
Macro Extension Tube Ring For CANON EOS DSLR 50D 5D 7D $6.65 |
|
|
Macro Extension Tube Ring For Canon 50mm F1.4 F1.8 AP02 $14.88 |
|
|
Macro Extension Tube Ring For Pentax FA 50mm F1.4 AP03 $14.88 |
|
|
Macro Extension Tube Ring For Nikon 50mm F1.4 F1.8 AP01 $14.88 |
|
|
Macro Extension Tube Ring For CANON EOS EF DSLR & SLR $6.72 |
|
|
Macro Extension Tube Ring for Nikon D700 D300 D90 D60 $6.72 |
|
|
Auto Focus Macro Extension Tube for CANON EOS EF EF-S $58.50 |
|
|
Auto Focus Macro Extension Tube For NIKON AF AF-S DX FX $59.10 |
|
|
Auto Focus Macro Extension Tube for Sony AF Minolta MA $79.99 |
|
|
Ihagee Dresden Extension Tubes 3 sets Boxed, EXC+++ $9.99 |
|
|
Macro Extension Tube Ring For NIKON Ai AF D5000 D5100 D80 D90 DSLR & SLR T004 $6.99 |
|
|
Macro Extension Tube Ring For Olympus 4/3 Lens E620 E600 E520 E4 DSLR T007 Metal $6.99 |
|
|
Macro Extension Tube Ring for Pentax K10D K20D K100D K110D K200D K-x K-R T005 $6.99 |
|
|
Macro Extension Tube Set for CANON 50D 40D 30D 1D 5D II 7D 550D 60D Black T003 $6.69 |
|
|
MeiKe Auto AF Extension tube EXT adjusted for Nikon EF D5100 D90 D7000 D800 $104.99 |
|
|
MeiKe Auto AF Extension tube EXT adjusted for Nikon EF D5100 D90 D7000 D800 $104.99 |
|
|
New Macro Extension Tube Ring FOR Canon EOS Rebel XT XTi XS XSi $73.81 |
|
|
Schacht M42 Auto extension tubes german made $39.50 |
|
|
Periflex L39 39mm 17.5mm extension tube LTM $20.53 |
|
|
M42 Extension Tubes – Turn any M42 lens into a Macro lens – Film and Digital $2.69 |
|
|
Macro Extension Tube Set for CANON Rebel t2i T1i EOS 10D 300D 20D $6.89 |
|
|
LEITZ NY, EXTENSION TUBE-FOCUSING (c. 1939) $175.00 |
|
|
Hasselblad C 21 Extension Tube $40.00 |
|
|
Hasselblad C 55 Extension Tube $40.00 |
|
|
Vivitar Macro Extension Tube Set fo Canon 60mm 100mm 70-300mm 18-200mm 18-55mm $73.99 |
|
|
Canon Extension Tube FL 25mm $24.99 |
|
|
Macro Automatic Extension Tube Set Nikon D40 D40X D50 D60 D70 D70S D80 105mm 60 $71.99 |
|
|
BRONICA SQ ZENZA S-18 Extension tube SQ-A, SQ-AM,SQ-Ai $35.00 |
|
|
Canon Extension Tube FL 15mm $19.99 |
|
|
Macro Extension Tube 3 Rings+Cleaning Pen For Canon EOS 550D 50D 7D 10D 20D 30D $8.99 |
|
|
3 Ring Macro Extension Tube for M42 Mount Camera Lens $6.89 |
|
|
Macro Extension 3 Ring Tube for Pentax K/PK Camera Lens $8.19 |
|
|
Macro Extension Tube Ring For NIKON Ai AF DSLR & SLR $8.19 |
|
|
Macro Extension Tube For Canon EOS 50D 40D 300D 350D 400D 1000D $6.89 |
|
|
Cleaning Pen+Macro Extension Tube for Canon EOS 5D 7D T3i T1i XT X Xti XS XSI $8.99 |
|
|
Leitz Leica TZFOO Extension Tube for TELYT on screw mount Cameras M39 $199.00 |
|
|
OLYMPUS OM FIT OZECK II MC MATCH MULTIPLIER 2X + MAKINON No. 2 EXTENSION TUBE $39.12 |
|
|
Vivitar Macro Extension Tube Set Canon T3i T2i 7D 60D 50D 40D 30D 20D 600D 550D $83.99 |
|
|
Kalcor Extension Tube Set for Pentax M42 Mount $19.95 |
|
|
Hasselblad Extension Tube 16 40541 $75.00 |
|
|
Olympus OM Zuiko 50mm f/3.5 macro lens & extension tubes $100.00 |
|
|
Hasselblad Extension Tube 55 55mm & USER MANUAL EXC++ IN BOX $84.99 |
|
|
For Canon EOS EF Camera Macro Extension Tube Ring Adapters $6.89 |
|
|
Canon EF12 II extension tube $42.00 |
|
|
For Canon Rebel XS XSI XT XTI T1i T2i Macro Extension Tube Ring $6.89 |
|
|
L9B Auto-Focus Macro Extension Tube for Canon Camera $74.48 |
|
|
Macro Extension Tube Ring For CANON EOS EF DSLR & SLR $6.89 |
|
|
Macro Extension Tube for Nikon D300 D300s D3100 D7000 $84.95 |
|
|
Macro Extension Tubes for Nikon D700 D3000 D90 D3s D3 $84.95 |
|
|
Auto Extension Tube Set for Canon FD $1.25 |
|
|
Nikon Nikonos 35mm f2.5 UW Lens with Macro Extension Tubes Box Mint +++ $57.95 |
|
|
For Canon DSLR & SLR 600D 1100D 550D Macro Extension Tube Set $6.89 |
|
|
Hasselblad 8MM Extension Tube #40649 $49.95 |
|
|
Leica OTRPO / Leitz 16471 Visoflex Extension Tube for 65mm, 9/13.5cm Lens Heads $78.59 |
|
|
Minolta ROKKOR-X MACRO 50mm f/3.5 With matched extension tube! 1:1 MACRO, MINTY! $127.50 |
|
|
Zena Bronica E-28 Extension Tube W/Front and Rear Caps $19.00 |
|
|
Macro Extension Tube Ring For CANON EOS DSLR 5D 7D 450D 400D 1000D $6.89 |
|
|
Vintage Repro N Extension Tube $2.36 |
|
|
AF Confirm Macro Extension Tube For Canon EOS EF Xti XS Xsi 60D $6.89 |
|
|
Hasselblad Extension Tubes 21 and 55 $37.00 |
|
|
NEW Macro Extension Tube Set for Nikon D40 D60 D80 D90 $7.89 |
|
|
M42 SCREW MOUNT SET OF PRINZFLEX EXTENSION TUBES FOR M42 MOUNT LENSES $15.79 |
|
|
Nikon M Extension Tube – EX/EX+ $22.00 |
|
|
Macro Extension Tube+Cleaning Pen For Canon EOS 50D 40D 300D 350D 400D 1000D $8.54 |
|
|
For Canon EOS 5D Mark II 20D 30D 350D 400D Macro Extension Tube 3 Ring $6.89 |
|
|
C-MOUNT EXTENSION TUBE SET – Close-Up, Macro – Bolex, Beaulieu, Kodak $0.99 |
|
|
Pentax or M42, 3 extension tube set FAIR CONDITION $13.40 |
|
|
Bronica Automatic Extension Tube – E 28 for ETRS / ETRSi + Free UK Postage $86.92 |
|
|
MINT ++ RARE PENTAX-A 100MM F2.8 SHARP MACRO SMC M 100MM ASAHI EXTENSION TUBE MF $1,229.99 |
|
|
Hasselblad 55mm Extension Tube For Macro Photography $59.99 |
|
|
Macro Extension Tube Olympus Evolt E500,E600,E330,E300 $35.95 |
|
|
Nikon Micro-Nikkor Auto 1:3.5 F=55mm w/M Extension Tube/ F/R Caps/Case/Non-AI $99.99 |
|
|
For Canon EOS Rebel XT Xti XSI Tli 5D 10D 300D Macro Extension Tube+Cleaning Pen $8.99 |
|
|
Vintage VIVITAR AUTOMATIC EXTENSION TUBE SET U/M-42, 12mm,20mm,36mm $27.99 |
|
|
CANON FD 50mm 1:3.5 MACRO LENS w/EXTENSION TUBE 25 1:1 T90 F-1 A-1 AE-1 $74.95 |
|
|
Macro Extension Tube for Canon 40D 400D 1000D 450D 50D $6.49 |
|
|
Macro Extension Tube for NIKON D5000，D90，D80，D70s , D50,D100, D40 ,NIKON F ,Ai $6.49 |
|
|
New AF Macro Extension Tube for Sony Alpha / Minolta MA Mount Adapter $6.49 |
|
|
MACRO EXTENSION TUBE FOR CANON BAYONET MOUNT 21MM, 13MM $14.80 |
|
|
3 Ring Macro Extension Tube For NIKON D5100/D90/D80/D70s $9.00 |
|
|
Mamiya 645e 80mm 55mm lens Macro spacer extension tube rapid wind grip in box $5.50 |
|
|
Extension Tube $6.56 Pricing subject to change. Extension Tube |
Positives Of Aluminum Tubing
Aluminum tubing is used in many different ways from the race track to household appliances and drinks cans. Aluminum is an excellent choice of metal as it has many desirable properties – it is cheap, widely available, easy to machine, hard to corrode, light weight and extremely tough and durable, in fact aluminum is around one third the weight of steel but almost as strong as some low carbon steel. Add to this the fact that aluminum extrusion produces incredibly cheap, yet high standard aluminum tubing, and there is little wonder that it is used on a large scale today.
Aluminum tubing can be made to a customer’s exact requirements and the lengths can be easily cut to specifications. There are so many different sizes of aluminum tubing all of which for different purposes. Aluminum tubing is used extensively in the racing industry, where it is used for exhausts and body parts for cars. When used in exhausts, aluminum tubing provides a durable and non corrosive part that can also withstand high temperatures without any loss of shape. When aluminum tubing is used in this way it will be bent to shape to form the exhaust and this is a straightforward process, although there can be hardening in the bend area, but this is a minor aspect which will not adversely effect the tubing.
Besides being a traditional round tube shape, aluminum tubing can be made in a whole host of different shapes, such as square or triangular to suit its end use. Such shaping can be used in products where a traditional round tube would not be appropriate. The building industry for example, use square tubing extensively in certain processes and the fact the aluminum tubing can be made so quickly and to the builder’s exact requirements it is a huge plus. Aluminum tubing can also be made into solid poles, which are more durable than the hollow tubes which can, if thin be bent out of shape with excess pressure. However, it is unlikely that an experienced builder or designer would use such a product when solid tubing would be needed.
Such is the precision of aluminum tubing manufacture today that the thinnest tubing can be created with ease and at speed due to the extrusion process. Once a die has been made for the aluminum tubing it can be replicated time and time again without any loss in quality. As a result the aluminum tubing produced is of a high standard and any extra finishing is not need as the tubing will be clean and free from any imperfections or surface scratches. This method of creating aluminum tubing is very cost effective and add to this the life of an extrusion die, which is practically infinite, then it is the obvious choice for anyone wanting to have aluminum tubing made.
One company that can offer all aluminum tubing solutions that are customer made is alfiniti.com and they can be found at www.alfiniti.com. Visit the website to find out the latest advances in aluminum tubing and extrusion services.
About the Author
Alfiniti provides
aluminum tubing
,
aluminum tube
and
aluminum extrusions
.
New Gallery Extension Proposed For V&A
The Victorian & Albert museum is to launch a competition to design a new gallery on its eastern flank. In the mid-1990s, the V&A museum ran a similar competition. The winner was Daniel Libeskind’s Spiral, a provocative £80m deconstructed block that somehow won planning permission from Kensington & Chelsea council. It didn’t, however, win favour from those holding the purse strings …