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Possible alternative to barlows/teleconverters (1 Viewer)
- Thread starter Paul Corfield
- Start date
DanC.Licks
AKA Daniel Bradley
Somehow these tests look crappy on this site. Here are the "originals". Scroll down to the bottom.
https://www.flickr.com/photos/42162009@N04/sets/72157634624330004/
https://www.flickr.com/photos/42162009@N04/sets/72157634624330004/
DanC.Licks
AKA Daniel Bradley
I remember my front element not coming out so easily either. Had to use a sharp awl in the N of CANON and a few taps with a small hammer. Not elegant, but I knew I would never want to re-build the sucker anyway... ;-)
Paul Corfield
Well-known member
Did some tests with 3 of my better magnifying optics. Tried to edit in Photoshop but CS6 doesn't let you open images of bank notes. Had to do very basic editing/saving in Microsoft paint.
On a £10 note I use the eyes as the ultimate test. Looking at the bank note with the human eye you can't even distinguish the very fine lines that make up the eye. It's probably even finer than feather detail making it a very good test of resolving power.
Lenses used were the new medium format 6X7 2X Vivitar TC that I got the other day, 2X Teleplus macro focusing TC and a TN from a Vivitar 100-200mm close focusing lens. Serial number on the lens starts with 28 showing it has high quality Komine made glass. Power is higher at around 2.5X. Mounting it as close to the camera as possible shows some softness in the corners. Spacing it away from the camera by about 15mm is enough to get rid of the soft corners but magnification is increased to around 3X or more making it quite powerful for normal use. Sharpness is excellent from the Komine glass and is the best of these three tests. I shall explore other Komine made lenses to see if I can turn up a lower powered gem. All three tests are very sharp overall. The two TC's were sharp to the corners. The 6X7 2X TC gives around 1.7X on my Nikon body which is much smaller than the medium format body that its intended for.
Paul.
On a £10 note I use the eyes as the ultimate test. Looking at the bank note with the human eye you can't even distinguish the very fine lines that make up the eye. It's probably even finer than feather detail making it a very good test of resolving power.
Lenses used were the new medium format 6X7 2X Vivitar TC that I got the other day, 2X Teleplus macro focusing TC and a TN from a Vivitar 100-200mm close focusing lens. Serial number on the lens starts with 28 showing it has high quality Komine made glass. Power is higher at around 2.5X. Mounting it as close to the camera as possible shows some softness in the corners. Spacing it away from the camera by about 15mm is enough to get rid of the soft corners but magnification is increased to around 3X or more making it quite powerful for normal use. Sharpness is excellent from the Komine glass and is the best of these three tests. I shall explore other Komine made lenses to see if I can turn up a lower powered gem. All three tests are very sharp overall. The two TC's were sharp to the corners. The 6X7 2X TC gives around 1.7X on my Nikon body which is much smaller than the medium format body that its intended for.
Paul.
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JGobeil
Nature Photographer
Discovering those TNs inside lenses are quite a feat. Thanks for sharing with us Paul ! I have 3 but I always use the same one from a Vivitar 80-200mm Macro SN# 77221315 at about 1.5X. It is on the SW80ED almost all the time for 1800mm net with the EM-1.
Best regards
Jules
Best regards
Jules
Paul Corfield
Well-known member
I remember the day I discovered it, it was one of those eureka moments. It's just in my nature to take anything and everything apart that has optics in and to try them out on the scope.
The 77 serial number is for Kobori and they made some really good lenses for Vivitar. Other ones to look at are 22 for Kiron, 28 for Komine and 61 who are Samyang. Kiron and Komine did a lot of the Vivitar Series One lenses which were their very best. The good thing with Vivitar was they used many makers and the serial numbers are well documented.
Paul.
JGobeil
Nature Photographer
Thanks for the info Paul. Kobori is a new name to me. The TN from the Vivitar lens seems very sharp.
DanC.Licks
AKA Daniel Bradley
Well, just when I was getting all excited about the new Canon 1.4x Extender Mark III, I decided to run it up against my old Olympus EC-14 on my scope. Guess what......
Bigger here:
https://farm8.staticflickr.com/7746/17331565811_f09b50d274_o.jpg
https://farm9.staticflickr.com/8748/16711701653_d627a6bf47_o.jpg
If I could only figure out a way to make a Canon EF -> 4/3 adapter, but there is only about 5.5mm to play with. Maybe I will just make a new TN to use with the Canon 400 out of a cheapie EF->m4/3 adapter. Can't use autofocus anyway and I don't see buying a Canon body, at least not right now, just to use my 400/5.6.
Bigger here:
https://farm8.staticflickr.com/7746/17331565811_f09b50d274_o.jpg
https://farm9.staticflickr.com/8748/16711701653_d627a6bf47_o.jpg
If I could only figure out a way to make a Canon EF -> 4/3 adapter, but there is only about 5.5mm to play with. Maybe I will just make a new TN to use with the Canon 400 out of a cheapie EF->m4/3 adapter. Can't use autofocus anyway and I don't see buying a Canon body, at least not right now, just to use my 400/5.6.
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Paul Corfield
Well-known member
Today on ebay I won a EBC X-FUJINON Z 75-150mm lens for just £6. Always wanted to get hold of an EBC lens to see what the electron beam coating is like. The EBC lenses had 11 layers of multicoatings. I shall post photos taken with the TN element when it arrives.
Last week I won a Vivitar lens on ebay. I took a punt because the photo was poor and the seller didn't list what size lens it was. It didn't matter as I got it for next to nothing. Unfortunately it was just a 200mm prime in M42 mount which can't be used on my Nikon camera. With the basic adapter it wont focus to infinity and the more expensive adapters with the correction lens in are basically rubbish. Rather than resell the lens I stripped it down and it turns out that the rear group is a form of TN. I found the rear group to be very sharp but there was CA visible in high contrast subjects and in out of focus areas. The original lens is known to suffer from CA anyway so maybe that's partly where it came from. Mag from the rear group was around 1.5X so a nice usable low power. So that's something to look into a bit more and I shall see what other cheap primes I can lay my hands on. The rear groups in zoom lenses are completely different and are of no use at all.
Paul.
Last week I won a Vivitar lens on ebay. I took a punt because the photo was poor and the seller didn't list what size lens it was. It didn't matter as I got it for next to nothing. Unfortunately it was just a 200mm prime in M42 mount which can't be used on my Nikon camera. With the basic adapter it wont focus to infinity and the more expensive adapters with the correction lens in are basically rubbish. Rather than resell the lens I stripped it down and it turns out that the rear group is a form of TN. I found the rear group to be very sharp but there was CA visible in high contrast subjects and in out of focus areas. The original lens is known to suffer from CA anyway so maybe that's partly where it came from. Mag from the rear group was around 1.5X so a nice usable low power. So that's something to look into a bit more and I shall see what other cheap primes I can lay my hands on. The rear groups in zoom lenses are completely different and are of no use at all.
Paul.
Paul Corfield
Well-known member
Did a test with the Fujinon TN to see how far I could push it for magnification. For the final image I used all my extension tubes between the TN and the camera to give 4.7X mag. On the 600mm SW80ED that's 2820mm and with my Nikon D3300 crop factor it's 4314.6mm equivalent.
First image is scope only, 2nd image is with the 1.8X TN mounted straight to camera, 3rd image is with a 50mm good quality macro tube between camera and TN and last image is with 180mm of macro tubes.
Wind was gusting to around 40mph when I did these. All taken with tripod axis loose and hand holding the camera. Surprised the bird just sat there singing as it was getting quite blown around.
Paul.
First image is scope only, 2nd image is with the 1.8X TN mounted straight to camera, 3rd image is with a 50mm good quality macro tube between camera and TN and last image is with 180mm of macro tubes.
Wind was gusting to around 40mph when I did these. All taken with tripod axis loose and hand holding the camera. Surprised the bird just sat there singing as it was getting quite blown around.
Paul.
Attachments
JGobeil
Nature Photographer
After seing this post, I monitored eBay for a similar lens and got one for 6$CDN... I received it today from Australia and it was worth ONLY 6$CDN... See the first 2 photos. I had never seen a lens in such a bad condition.
I was able to salvage the back lens assembly quite easily using small screwdrivers but it was another story for the front elements. I finally got 2 elements out using a Dremel tool with a rotary saw... I was unable to salvage the large front element. What a mess...
The 3rd photo shows what remains. It still needs some cleaning but the glass elements are in perfect shape.
Paul, if you read this, what parts of the lens have you used to make the TN ?
Attachments
JGobeil
Nature Photographer
I made a TN using the 2 bottom lens assemblies shown in the last photo of my post of yesterday.
They are almost a perfect fit for the cheap M43 extention tubes found on eBay. The fit is perfect at the camera end and just a bit of grinding with a Dremel with sand paper make it a tight fit at the other end.
The length is perfect when the extension tube is made of a only a 14mm center tube with the 2 bayonnet ends. I measured 1.33X, a bit low for my taste, so I added a 7mm center tube to spread the 2 lens assemblies and it is now 1.42X, just what I wanted - a rubber spacer kept everything in place.
Paul measured 1.8X for his TN made from the same lens so he probably didn't use the same lens elements or a different assembly.
Quick tests seem to show sharp images without CA.
They are almost a perfect fit for the cheap M43 extention tubes found on eBay. The fit is perfect at the camera end and just a bit of grinding with a Dremel with sand paper make it a tight fit at the other end.
The length is perfect when the extension tube is made of a only a 14mm center tube with the 2 bayonnet ends. I measured 1.33X, a bit low for my taste, so I added a 7mm center tube to spread the 2 lens assemblies and it is now 1.42X, just what I wanted - a rubber spacer kept everything in place.
Paul measured 1.8X for his TN made from the same lens so he probably didn't use the same lens elements or a different assembly.
Quick tests seem to show sharp images without CA.
Paul Corfield
Well-known member
JGobeil
Nature Photographer
Thanks Paul.
I thaught that the 2 assemblies were made to go together. Using only the larger one, like you do, gives me 1.51X. Right where I want it. Of course it makes no sense to use more glass to get less magnification... and the TN is 7mm shorter.
Images seem quite sharp but contrast could be better. Using a smaller aperture at the camera end should improve it. As it is now, the aperture is 35 mm, the full width of the extension tube.
Best regards
Jules
I thaught that the 2 assemblies were made to go together. Using only the larger one, like you do, gives me 1.51X. Right where I want it. Of course it makes no sense to use more glass to get less magnification... and the TN is 7mm shorter.
Images seem quite sharp but contrast could be better. Using a smaller aperture at the camera end should improve it. As it is now, the aperture is 35 mm, the full width of the extension tube.
Best regards
Jules
Attachments
Paul Corfield
Well-known member
Just that one that I showed is the main TN, it's the one that travels the most distance when the lens is zoomed in and out. The other one isn't needed and doesn't provide a useful magnification as you saw. The main TN itself is an air spaced triplet design. It has a doublet at the back, then a thin spacer and a single element at the front. For contrast I'm using a set of aperture blades scavenged from an old lens.
Paul.
Paul.
JGobeil
Nature Photographer
Just like if they were made to go together... I made a TC with aperture control using the TN removed from the EBC X-FUJINON Z 75-150mm lens.
I ordered a M43 to EOS adapter with aperture control on eBay for 30$ including shipping. The female connector and a 14mm extension tube from a cheap 10$ M43 Extension Tube Set make a perfect fitting replacement for the EOS connector. The fit is perfect but the extension tube was still quite easy to remove so I glued it in place with 4 drops of Crazy Glue.
Like I reported before, the TN is almost a perfect fit inside the M43 extension set. Removing the paint and a bit of metal inside the female connector using sandpaper with a Dremel tool is all that is needed. It is a tight fit but a small soft plastic spacer secures it perfectly.
It is easy to add extension tubes to give the TN the magnification desired. 7, 14 and 28mm tubes are available.
Width: 65mm
Height: 45mm
Weight: 187 g.
Cost: less than 50$.
I didn't get a chance to test it because it has been raining since I received it but I will report here as soon as it is done.
Adapter with aperture:
http://www.ebay.ca/itm/Build-in-Ape...hash=item56478363e4:m:mDQoceXQMWSSbfavA6vNgdA
Extension set:
http://www.ebay.ca/itm/Macro-Extens...hash=item3f2c0cae88:m:mHIFLnt4or3iojkCuERmpZQ
I ordered a M43 to EOS adapter with aperture control on eBay for 30$ including shipping. The female connector and a 14mm extension tube from a cheap 10$ M43 Extension Tube Set make a perfect fitting replacement for the EOS connector. The fit is perfect but the extension tube was still quite easy to remove so I glued it in place with 4 drops of Crazy Glue.
Like I reported before, the TN is almost a perfect fit inside the M43 extension set. Removing the paint and a bit of metal inside the female connector using sandpaper with a Dremel tool is all that is needed. It is a tight fit but a small soft plastic spacer secures it perfectly.
It is easy to add extension tubes to give the TN the magnification desired. 7, 14 and 28mm tubes are available.
Width: 65mm
Height: 45mm
Weight: 187 g.
Cost: less than 50$.
I didn't get a chance to test it because it has been raining since I received it but I will report here as soon as it is done.
Adapter with aperture:
http://www.ebay.ca/itm/Build-in-Ape...hash=item56478363e4:m:mDQoceXQMWSSbfavA6vNgdA
Extension set:
http://www.ebay.ca/itm/Macro-Extens...hash=item3f2c0cae88:m:mHIFLnt4or3iojkCuERmpZQ
Attachments
DanC.Licks
AKA Daniel Bradley
I fear you are going to get some pretty serious vignetting if you stop down....
Hope I am wrong!
Hope I am wrong!
