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Pancolart
Joined: 04 Feb 2008 Posts: 3704 Location: Slovenia, EU
Expire: 2013-11-18
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Posted: Tue May 21, 2013 12:56 pm Post subject: In search for: Speedbooster SUBSTITUTE |
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Pancolart wrote:
Assuming this is a correct formula (found on Ebay):
And this is Helios scheme:
One could hope to find a low priced (under 50 EUR) lens including the Important part . Any ideas? _________________ ---------------------------------
The Peculiar Apparatus Of Victorian Steampunk Photography: 100+ Genuine Steampunk Camera Designs https://www.amazon.com/dp/B0B92829NS |
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std
Joined: 09 Feb 2010 Posts: 1826 Location: Bulgaria
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Posted: Tue May 21, 2013 1:57 pm Post subject: |
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std wrote:
So you are looking for cheap helios? _________________ Stefan
My lens list:
SLR MD: Rokkor 1,7/50 Exakta: Kilfitt-Makro-Kilar E 3.5/4cm; CZJ 2/50 Pancolar;M42: CZJ 2.8/50 Tessar; Mir-1B 2.8/37; Jupiter-9 2/85 T-mount: Tamron 5.9/200; Tamron 6.9/300; Tamron 7.5/400 C-mount: Cosmicar 1.8/50 Y/S: Sun 3.5/38-90, Sun 4/70-210 RF Contax RF: Jupiter-8 2/50; Contax G:CZ 2,8/21 Biogon T; CZ 2,8/28 Biogon T; CZ 2/35 Planar T; CZ 2/45 Planar T; CZ 2,8/90 Sonnar T |
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Pancolart
Joined: 04 Feb 2008 Posts: 3704 Location: Slovenia, EU
Expire: 2013-11-18
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Posted: Tue May 21, 2013 2:20 pm Post subject: |
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Pancolart wrote:
No. For a lens that already "includes" Speedbooster as part of it's design. So i could harvest it. Might be some zoom's rear. _________________ ---------------------------------
The Peculiar Apparatus Of Victorian Steampunk Photography: 100+ Genuine Steampunk Camera Designs https://www.amazon.com/dp/B0B92829NS |
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simbon4o
Joined: 19 Dec 2011 Posts: 390 Location: Bulgaria
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Posted: Tue May 21, 2013 5:09 pm Post subject: |
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simbon4o wrote:
I think you actually need wide angle convertor. _________________ 10-300мм 4.0 - 1.2 - 4.5 NIKON&Sony bodies / Sony 10-18, Pentax 28 2.8 II, CZJ 35 2.4, Nikkor DX 35 1.8, Samyang 35 1.4, KMZ 50 1.7, FDn 50 1.2 L, Nikkor 55 2.8, Rokkor 58 1.2, Soligor 85 1.8 Preset, Samyang 85 1.4, Canon FDn 85 1.2 L, Tokina AT-X 90 2.5, Canon FDn 135mm 2.0, Nikkor 180 2.8 ED, Tair 300 4.5
________
snimo.net |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Tue May 21, 2013 5:29 pm Post subject: |
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iangreenhalgh1 wrote:
Yup, that diagram does look like a wide angle converter.
They are usually way too large to fit behind a lens and most of them reduce IQ quite a lot.
Even if you could harvest something, all you'd end up doing is making a neat device for ruining the IQ of lenses. _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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buerokratiehasser
Joined: 12 Jun 2011 Posts: 470
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Posted: Tue May 21, 2013 6:32 pm Post subject: |
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buerokratiehasser wrote:
I dunno, this thing is an anti-teleconverter right?
Can't you simply use a contraption that doesn't stack up to flange distance (with 4/3 etc.)
Like, i got exakta to m39 thingie here..
you will lose the short end (infinity at 3 m or so) but who cares? (okay. people who want these crazy UWW shots with three feet distance do care) |
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nukemall
Joined: 24 Apr 2012 Posts: 96 Location: Blagoveschensk, Russia
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Posted: Wed May 22, 2013 1:16 am Post subject: |
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nukemall wrote:
Simple focal reducer is just strong positive lens. You can try +5 - +10 acromatic macro close-up lens(two +5 lenses = +10).
_________________ My blog |
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nukemall
Joined: 24 Apr 2012 Posts: 96 Location: Blagoveschensk, Russia
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Posted: Wed May 22, 2013 1:35 am Post subject: |
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nukemall wrote:
Reduction factor(R) of the reducer is a function of the focal length (FR) of the reducer and its distance (D) from the camera’s focal plane:
R=1-D/FR
Focal length of +10 lens is 1000/10=100mm (+5 lens - 1000/5=200mm).
So if you place +10 lens at 20mm from the focal plane it will be 1-20/100=0.8X focal reducer. _________________ My blog |
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ForenSeil
Joined: 15 Apr 2011 Posts: 2726 Location: Kiel, Germany.
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Posted: Wed May 22, 2013 2:14 am Post subject: |
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ForenSeil wrote:
A speed booster is nothing more than a good corrected loupe!(!!!)
Hold a loupe in front of your sensor and you will see how simple it works - it makes the sensor looking larger / expandig the sensor optically. (Exactly the opposite of what a teleconverter is doing - it makes the sensor looking smaller)
I would try any decent well corrected close-ups lenses (Raynox etc.) instead of lens parts.
The Helios 44 rear part won't work at all, it's too "specialised" - I guess it will give you small coverage and heavy abberation.
Have you seen this thread http://forum.mflenses.com/poor-mans-diy-speed-booster-t57639,highlight,%2Bdiy.html ? _________________ I'm not a collector, I'm a tester
My camera: Sony A7+Zeiss Sonnar 55/1.8
Current favourite lenses (I have many more):
A few macro-Tominons, Samyang 12/2.8, Noritsu 50.7/9.5, Rodagon 105/5.6 on bellows, Samyang 135/2, Nikon ED 180/2.8, Leitz Elmar-R 250/4, Celestron C8 2000mm F10
Most wanted: Samyang 24/1.4, Samyang 35/1.4, Nikon 200/2 ED
My Blog: http://picturechemistry.own-blog.com/
(German language) |
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dan_
Joined: 05 Dec 2012 Posts: 1056 Location: Romania
Expire: 2016-12-19
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Posted: Wed May 22, 2013 11:49 am Post subject: |
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dan_ wrote:
nukemall and ForenSeil pointed it out very well.
I did tested quality achromats as focal reducers, not to substitute the Speed Booster but to adapt some MF/LF lenses of a focal length of 80-150 mm. to my Sony NEX with a greater reducing factor then x0.7 (~x0.5).
My unscientific conclusions are:
- you get 1-2 f-stops increase in luminosity;
- you get very good central resolution (probably a little increase in central resolution);
- chromatic aberrations are acceptable;
- corner resolution degrades a little. The degradation is proportional with the power of the achromats used. For a power of less then +5D it is acceptable in most real life situations (but not for sharp infinity landscapes, architecture, etc!);.
- spherical aberrations are increasing to corners. More low power achromats are better then a single powerful one. Circles became ellipses as getting closer to the corners. Again, at a power of less then +5D (with 2 achromats of lower power) it is acceptable in most real life situations (and again, not for infinity landscapes, architecture, etc!).
The setup can be successfully used for portraits, close-ups and whenever you want to separate the subject from the background and corners are not so important.
It may be not acceptable for landscapes, architecture, flat objects and whenever the sharpness in corners and geometrical precision are very important.
Considering the financial point of view such a project is hardly feasible. You'll have to pay for the quality achromatic lenses, for adapters, for modifying the adapters to the new register distance (diminished by the achromats), for special rings to mount the achromats in the adapter. The final cost makes the Chinese Lens Turbo very appealing (considering that it is much better corrected).
For my MF/LF lenses I think the best solution is to use a Lens Turbo + low power achromats (better front mounted, for simplicity) in order to get a ~x0.5 reducing factor.
Last edited by dan_ on Wed May 22, 2013 11:53 am; edited 1 time in total |
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Pancolart
Joined: 04 Feb 2008 Posts: 3704 Location: Slovenia, EU
Expire: 2013-11-18
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Posted: Sat May 25, 2013 4:18 pm Post subject: |
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Pancolart wrote:
Question: wouldn't optimal speed-booster had to be VARIO? I was thinking different scheme & distances (in-between elements and lens to sensor) would be required if you boost tele or ultra wide lens? What do you think? _________________ ---------------------------------
The Peculiar Apparatus Of Victorian Steampunk Photography: 100+ Genuine Steampunk Camera Designs https://www.amazon.com/dp/B0B92829NS |
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calvin83
Joined: 12 Apr 2009 Posts: 7555 Location: Hong Kong
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Posted: Sat May 25, 2013 4:38 pm Post subject: |
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calvin83 wrote:
Pancolart wrote: |
Question: wouldn't optimal speed-booster had to be VARIO? I was thinking different scheme & distances (in-between elements and lens to sensor) would be required if you boost tele or ultra wide lens? What do you think? |
The space for the glass may not be enough for a vario focal reducer. The designer have to choose optimize for tele, normal or wide angle lens. _________________ https://lensfever.com/
https://www.instagram.com/_lens_fever/
The best lens is the one you have with you. |
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kuuan
Joined: 14 Jan 2008 Posts: 4569 Location: right now: Austria
Expire: 2014-12-26
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Posted: Sat May 25, 2013 4:41 pm Post subject: |
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kuuan wrote:
dan_ wrote: |
....
Considering the financial point of view such a project is hardly feasible. You'll have to pay for the quality achromatic lenses, for adapters, for modifying the adapters to the new register distance (diminished by the achromats), for special rings to mount the achromats in the adapter. The final cost makes the Chinese Lens Turbo very appealing (considering that it is much better corrected).
For my MF/LF lenses I think the best solution is to use a Lens Turbo + low power achromats (better front mounted, for simplicity) in order to get a ~x0.5 reducing factor. |
the price of the lens turbo has started dropping, jinfinance from 198.- to 195.- ( + 3.75 shipping ), now roxsen offers it for 185.- ( free shipping ) and there is another one offered by 'lengril' for 189.- ( free shipping and a differing lettering on it. yet aother piece, or the same lens turbo? )
guess price will drop somewhat more soon _________________ my photos on flickr: https://www.flickr.com/photos/kuuan/collections |
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iangreenhalgh1
Joined: 18 Mar 2011 Posts: 15679
Expire: 2014-01-07
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Posted: Sat May 25, 2013 5:07 pm Post subject: |
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iangreenhalgh1 wrote:
It's a lot of money just to shoot wide open with reduced IQ.
If this was such a good idea, why hasn't Leica or Zeiss or one of the major Japanese makers made something like this?
Cheap Chinese glass is bound to just make all your lenses look like cheap Chinese glass, we've seen what the cheap Canon FD-EOS adapters with glass do to the IQ of lenses. They aren't making these to be as good as they can be, but as cheap as they can be.
Faster but worse, that's a poisoned chalice if ever I saw one. _________________ I don't care who designed it, who made it or what country it comes from - I just enjoy using it! |
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calvin83
Joined: 12 Apr 2009 Posts: 7555 Location: Hong Kong
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Posted: Sat May 25, 2013 5:45 pm Post subject: |
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calvin83 wrote:
I think some people will use it for wide angle resize on web while some other use it on standard/tele lens for portrait to gain soft effect and DOF. It is just a tool for those who need the benefit and can stand for the drawbacks. _________________ https://lensfever.com/
https://www.instagram.com/_lens_fever/
The best lens is the one you have with you. |
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kuuan
Joined: 14 Jan 2008 Posts: 4569 Location: right now: Austria
Expire: 2014-12-26
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Posted: Sat May 25, 2013 5:53 pm Post subject: |
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kuuan wrote:
To use my SLR lenses close to the view they had been designed for on a small NEX is just too compelling, and the reducer makes the package even smaller than with a normal adapter.
Reports say and show that center resolution might even be improved and I don't give a damn about degraded corners, won't use a reducer for landscape or architecture shots where that might play a role. _________________ my photos on flickr: https://www.flickr.com/photos/kuuan/collections |
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calvin83
Joined: 12 Apr 2009 Posts: 7555 Location: Hong Kong
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Posted: Sat May 25, 2013 6:08 pm Post subject: |
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calvin83 wrote:
kuuan wrote: |
To use my SLR lenses close to the view they had been designed for on a small NEX is just too compelling, and the reducer makes the package even smaller than with a normal adapter.
Reports say and show that center resolution might even be improved and I don't give a damn about degraded corners, won't use a reducer for landscape or architecture shots where that might play a role. |
These focal reducer will increase the center resolution. The Speed Booster White Paper has the MTF for wide, standard and tele lens. From the current sample and test on the web, I think this focal reducer will behave similarly to the Speed Booster.
http://www.metabones.com/images/metabones/Speed%20Booster%20White%20Paper.pdf _________________ https://lensfever.com/
https://www.instagram.com/_lens_fever/
The best lens is the one you have with you. |
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eno789
Joined: 27 Aug 2010 Posts: 159 Location: California
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Posted: Sat May 25, 2013 6:16 pm Post subject: |
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eno789 wrote:
iangreenhalgh1 wrote: |
It's a lot of money just to shoot wide open with reduced IQ.
If this was such a good idea, why hasn't Leica or Zeiss or one of the major Japanese makers made something like this?
Cheap Chinese glass is bound to just make all your lenses look like cheap Chinese glass, we've seen what the cheap Canon FD-EOS adapters with glass do to the IQ of lenses. They aren't making these to be as good as they can be, but as cheap as they can be.
Faster but worse, that's a poisoned chalice if ever I saw one. |
Who says you have to shoot wide open?
I just got my Lens Turbo, and need to shoot more to form an opinion. But I would not base my opinion on those cheap FD-EOS 1-element adapters anyway.
There're good teleconverters, and bad teleconverters. There're good diopters, and bad diopters. I'd expect the same with focal reducers. Especially with focal reducers, there'll be more light gathered, so theoretically it's even possible to have improved IQ in the center. To me it's just another tool in the box. _________________ Sharpness from lenses; Softness from me.
Nikon DSLR, Sony Mirrorless, Panasonic mu-4/3 - Having fun with MF lenses
https://www.flickr.com/groups/painterly_bokeh |
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philslizzy
Joined: 07 Aug 2012 Posts: 4744 Location: Cheshire, England
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Posted: Sat May 25, 2013 6:20 pm Post subject: |
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philslizzy wrote:
calvin83 wrote: |
...It is just a tool for those who need the benefit and can stand for the drawbacks. |
I think so too. I want a lens turbo. _________________ Hero in the 'messin-with-cameras-for-the-hell-of-it department'. Official. |
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kuuan
Joined: 14 Jan 2008 Posts: 4569 Location: right now: Austria
Expire: 2014-12-26
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Posted: Sat May 25, 2013 6:45 pm Post subject: |
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kuuan wrote:
and thinking of it, using the 'lens turbo' will mean not having to clean the sensor of my NEX all that often any more _________________ my photos on flickr: https://www.flickr.com/photos/kuuan/collections |
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fermy
Joined: 17 Feb 2012 Posts: 1974
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Posted: Sat May 25, 2013 6:50 pm Post subject: |
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fermy wrote:
It's interesting to note though that diagrams for Speedbooster and Lens-Turbo are very different.
Speed booster:
Lens Turbo:
The first reports on Lens Turbo are quite mixed though, more so than on speedbooster. _________________ Many lenses and some film bodies for sale here: http://forum.mflenses.com/canon-fd-minolta-md-c-mounts-m42-pentax-and-more-t50465.html
Flickr http://www.flickr.com/photos/96060788@N06/ |
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