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Ernst Dinkla
Joined: 30 Nov 2016 Posts: 378
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Posted: Wed Sep 18, 2019 7:07 am Post subject: |
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Ernst Dinkla wrote:
Sciolist wrote: |
Ernst Dinkla wrote: |
Are you sure the Color Skopar has front cell focusing? The Color Skopar 50mm 2.8 that I took from a Vito BL is actually unit focusing. That the front turns in focusing and everything is small confused me till I removed it and saw the total lens move when focused. If it is front cell focusing then 40x the focal length so 20 meter / 66 feet should be the optimal setting for the front cell when focused by a separate helicoid. The optical design compromised on that distance.
Image quality of my 2.8 can still amaze me. https://www.dpreview.com/challenges/Entry.aspx?ID=1117739&View=NewFirst&Rows=4 |
Hi Ernst. Yes, I've just checked again to make sure and it is front cell focusing. The lens fits the Vito IIa folder. Thanks for providing the calculation. I'd concluded that infinity was better than mfd, and better than setting it somewhere in the middle, but that is as far as I had got. Now I can set it to 66' .
Do you know if the 40x calculation can be applied to any front cell focusing lens? |
I also struggled with that question 16 years ago and asked around: https://www.photo.net/discuss/threads/front-cell-focusing-optimal-distance-setting.58647/
The answer that referred to a German book was the one I found most plausible, at least for lenses made in Germany. _________________ Met vriendelijke groet, Ernst
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
March 2017 update, 750+ inkjet media white spectral plots |
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Sciolist
Joined: 29 Mar 2017 Posts: 1445 Location: Scotland
Expire: 2021-04-16
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Posted: Wed Sep 18, 2019 8:31 am Post subject: |
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Sciolist wrote:
Thanks for having a good memory, that was a good link. I notice that roland_haid states the focal distance setting should be, using the Stuper calculation, 2m, rather than 20m. Am I reading that right? |
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Ernst Dinkla
Joined: 30 Nov 2016 Posts: 378
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Posted: Wed Sep 18, 2019 10:43 am Post subject: |
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Ernst Dinkla wrote:
Sciolist wrote: |
Thanks for having a good memory, that was a good link. I notice that roland_haid states the focal distance setting should be, using the Stuper calculation, 2m, rather than 20m. Am I reading that right? |
Sorry, my mistake. 50mm 40x sure is 2 meter so 6.66 feet. Memory still good but age compromises other parts of the brain. _________________ Met vriendelijke groet, Ernst
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
March 2017 update, 750+ inkjet media white spectral plots |
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Sciolist
Joined: 29 Mar 2017 Posts: 1445 Location: Scotland
Expire: 2021-04-16
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Posted: Wed Sep 18, 2019 11:37 am Post subject: |
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Sciolist wrote:
Ernst Dinkla wrote: |
Sciolist wrote: |
Thanks for having a good memory, that was a good link. I notice that roland_haid states the focal distance setting should be, using the Stuper calculation, 2m, rather than 20m. Am I reading that right? |
Sorry, my mistake. 50mm 40x sure is 2 meter so 6.66 feet. Memory still good but age compromises other parts of the brain. |
I didn't notice either Ernst. You are not alone. |
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Alun Thomas
Joined: 20 Aug 2018 Posts: 614 Location: New Zealand
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Posted: Thu Sep 19, 2019 1:39 am Post subject: |
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Alun Thomas wrote:
A lens I haven't seen around before, from a company only known for one other SLR style lens that google can find for me. I havn't been able to find any information on this particular lens, and haven't noticed it on other badges either. In use, it is competent, maybe even above average, for the period it was released. |
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sergtum
Joined: 14 Nov 2016 Posts: 735
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Posted: Thu Sep 19, 2019 4:35 pm Post subject: |
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sergtum wrote:
DSC01610 by Mr TTT, on Flickr
my thanks to Switzerland. |
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KEO
Joined: 27 Sep 2018 Posts: 756 Location: USA
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Posted: Thu Sep 19, 2019 7:52 pm Post subject: |
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KEO wrote:
sergtum wrote: |
my thanks to Switzerland. |
Great lens!
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Sciolist
Joined: 29 Mar 2017 Posts: 1445 Location: Scotland
Expire: 2021-04-16
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Posted: Fri Sep 20, 2019 11:29 am Post subject: |
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Sciolist wrote:
1948 Schneider-Kreuznach Xenon 1:2/50.
This early coating shows as a pale blue-grey. It's one I've never encountered before, and quite lovely. |
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walter g
Joined: 20 Feb 2010 Posts: 2463 Location: NC, USA
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Posted: Fri Sep 20, 2019 12:07 pm Post subject: |
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walter g wrote:
Alun Thomas wrote: |
A lens I haven't seen around before, from a company only known for one other SLR style lens that google can find for me. I havn't been able to find any information on this particular lens, and haven't noticed it on other badges either. In use, it is competent, maybe even above average, for the period it was released. |
That is an early lens. It still has the Ichizuka optical company markings on it. Very, Very cool. _________________
Main cameras
Panasonic G5,Nikon J1,Pentax Q10,Sony Nex 6
Minolta MC W SI 2.5/28, MD 2.8/28, MC W SG 3.5/28, MC Celtic 3.5/28, MC W HG 2.8/35, MD Celtic 2.8/35, QE 4/35, Rokkor X 2/45, MC Rokkor X PG 1.4/50, MC Rokkor X PG 1.7/50, MD Rokkor X 1.7/50, MD 2/50, MC Rokkor PF 1.7/55, MC Rokkor PF 1.9/55, Auto Tele Rokkor PG 2.8/135, MC Tele Rokkor QD 3.5/135, TC 4/135, MC Celtic 4/200, MC Tele Rokkor PE 4.5/200
MD 28-70 f3.5-4.8, MD Macro 35-70 f3.5, Md 70-210 f4, MD Rokkor X 75-200 f4.5, MD 100-200 f5.6
Nikon Nikkor 4/20, O Auto 2/35, S Auto 1.4/50..... Miranda Auto 2.8/28, Auto 2.8/35, Auto 1.4/50, Auto EC 1.4/50, Auto 1.8/50, Auto EC 1.8/50,Auto 1.9/50, Auto 3.5/135
Various Soligor,Sun,Fujita,Komura,Spitatone, etc. Lenses
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marcusBMG
Joined: 07 Dec 2012 Posts: 1301 Location: Conwy N Wales
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Posted: Fri Sep 20, 2019 7:17 pm Post subject: |
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marcusBMG wrote:
I've been looking for a pka mount komine made 90mm macro for about 3 yrs..
_________________ pentax ME super (retired)
Pentax K3-ii; pentax K-S2; Samsung NX 20; Lumix G1 + adapters;
Adaptall collection (proliferating!) inc 200-500mm 31A, 300mm f2.8, 400mm f4.
Primes: takumar 55mm; smc 28mm, 50mm; kino/komine 28mm f2's, helios 58mm, Tamron Nestar 400mm, novoflex 400mm, Vivitar 135mm close focus, 105mm macro; Jupiter 11A; CZJ 135mm.
A classic zoom or two: VS1 (komine), Kiron Zoomlock... |
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BurstMox
Joined: 04 Dec 2011 Posts: 1998 Location: France
Expire: 2016-08-02
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Posted: Fri Sep 20, 2019 8:33 pm Post subject: |
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BurstMox wrote:
Rare Uran-25 200/2.5 from GOI. A lens for aerial photography, designed for 8x8 format.
#1
#2
#3
#4
_________________ Pierre
sovietlenses.fr
Soviet lenses Facebook group |
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walter g
Joined: 20 Feb 2010 Posts: 2463 Location: NC, USA
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Posted: Mon Sep 23, 2019 8:58 pm Post subject: |
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walter g wrote:
Minolta MC W Rokkor X 28mm f2. I already have the Minolta MDiii 28mm f2, but I wanted to try the MC version. Lens is in exc+ condition.
Except....
It has one issue which the seller documented.
Seperation. It is along one edge, and so far with preliminary testing it doesn't show in the pics.
I'm waiting on my new computer to do full testing, and check the results. Let's just say at f16 looking at the rear screen I can't see any issues.
Is this the cheapest Minolta 28mm f2 to ever sell on eBay. Possibly. It was $25 shipped.😀😀😀😀 _________________
Main cameras
Panasonic G5,Nikon J1,Pentax Q10,Sony Nex 6
Minolta MC W SI 2.5/28, MD 2.8/28, MC W SG 3.5/28, MC Celtic 3.5/28, MC W HG 2.8/35, MD Celtic 2.8/35, QE 4/35, Rokkor X 2/45, MC Rokkor X PG 1.4/50, MC Rokkor X PG 1.7/50, MD Rokkor X 1.7/50, MD 2/50, MC Rokkor PF 1.7/55, MC Rokkor PF 1.9/55, Auto Tele Rokkor PG 2.8/135, MC Tele Rokkor QD 3.5/135, TC 4/135, MC Celtic 4/200, MC Tele Rokkor PE 4.5/200
MD 28-70 f3.5-4.8, MD Macro 35-70 f3.5, Md 70-210 f4, MD Rokkor X 75-200 f4.5, MD 100-200 f5.6
Nikon Nikkor 4/20, O Auto 2/35, S Auto 1.4/50..... Miranda Auto 2.8/28, Auto 2.8/35, Auto 1.4/50, Auto EC 1.4/50, Auto 1.8/50, Auto EC 1.8/50,Auto 1.9/50, Auto 3.5/135
Various Soligor,Sun,Fujita,Komura,Spitatone, etc. Lenses
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stevemark
Joined: 29 Apr 2011 Posts: 3751 Location: Switzerland
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Posted: Mon Sep 23, 2019 9:45 pm Post subject: |
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stevemark wrote:
walter g wrote: |
Minolta MC W Rokkor X 28mm f2. I already have the Minolta MDiii 28mm f2, but I wanted to try the MC version. Lens is in exc+ condition.
Except....
It has one issue which the seller documented.
Seperation. It is along one edge, and so far with preliminary testing it doesn't show in the pics.
I'm waiting on my new computer to do full testing, and check the results. Let's just say at f16 looking at the rear screen I can't see any issues.
Is this the cheapest Minolta 28mm f2 to ever sell on eBay. Possibly. It was $25 shipped.😀😀😀😀 |
As all the MC-X lenses it is a joy to work with. I got it, years ago, in a local store for CHF 150.--, also in like new condition (but without lens separation, of course). Later i found the MD-III version (which is the better performer), and recently the MD-II came along (same optical formula as the MC-X 2/28mm). The MC-X 2.5/25mm is even smoother to operate (it has no floating focusing), and it is a very good vintage lens as well.
Stephan _________________ www.artaphot.ch |
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walter g
Joined: 20 Feb 2010 Posts: 2463 Location: NC, USA
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Posted: Tue Sep 24, 2019 12:25 pm Post subject: |
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walter g wrote:
Stephan,
I have a collection of MC X lenses and like them all. This lens seems to drop into focus really easy, which seems to be a trait of some but not all Minolta lenses.
I also have the 28mm f2.5, but unfortunately both of my copies are yellowed and need treatment. It's amazing the image quality difference between different levels of yellowing. _________________
Main cameras
Panasonic G5,Nikon J1,Pentax Q10,Sony Nex 6
Minolta MC W SI 2.5/28, MD 2.8/28, MC W SG 3.5/28, MC Celtic 3.5/28, MC W HG 2.8/35, MD Celtic 2.8/35, QE 4/35, Rokkor X 2/45, MC Rokkor X PG 1.4/50, MC Rokkor X PG 1.7/50, MD Rokkor X 1.7/50, MD 2/50, MC Rokkor PF 1.7/55, MC Rokkor PF 1.9/55, Auto Tele Rokkor PG 2.8/135, MC Tele Rokkor QD 3.5/135, TC 4/135, MC Celtic 4/200, MC Tele Rokkor PE 4.5/200
MD 28-70 f3.5-4.8, MD Macro 35-70 f3.5, Md 70-210 f4, MD Rokkor X 75-200 f4.5, MD 100-200 f5.6
Nikon Nikkor 4/20, O Auto 2/35, S Auto 1.4/50..... Miranda Auto 2.8/28, Auto 2.8/35, Auto 1.4/50, Auto EC 1.4/50, Auto 1.8/50, Auto EC 1.8/50,Auto 1.9/50, Auto 3.5/135
Various Soligor,Sun,Fujita,Komura,Spitatone, etc. Lenses
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koji
Joined: 21 Jul 2008 Posts: 2106 Location: Hiroshima, Japan
Expire: 2012-12-27
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Posted: Tue Sep 24, 2019 6:01 pm Post subject: |
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koji wrote:
Buy one of these to de-yellow those lenses.
36W UV curing lamp for nail art which uses four UV-A Lamp type 3's
I put two Minolta MC lenses, let's see.
1) MC W.Rokkor-HH 35mmF/1.8 > http://www.pbase.com/kkawakami/image/162568924
2) MC W.Rokkor-SI 28mmF/2.5 > http://www.pbase.com/kkawakami/image/162637027
3) CZJ Prakticar 50mmF/1.4(I) > http://www.pbase.com/kkawakami/image/165458935
4) CANON FD 35mmF/2 (II) .... > http://www.pbase.com/kkawakami/image/166377327
You do not need to use UV-C lamps to de-yellowing lenses, safer and easier with UV-A,
UV-C is too strong and may damage the lens' black anodization exteriors. This lamp is
Canadian $35 or so, one set of replacement lamps was CAD$17 (last about 500 hours). _________________ Our Home Page has 18,200 photos in 575 directories today.
Lenses: https://www.pbase.com/kkawakami/top_level_my_lenses |
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KEO
Joined: 27 Sep 2018 Posts: 756 Location: USA
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Posted: Tue Sep 24, 2019 8:03 pm Post subject: |
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KEO wrote:
koji wrote: |
Buy one of these to de-yellow those lenses. |
That looks like the right size for most radioactive lenses, and it bombards from multiple directions. Nice.
Does it come colors other than pink?
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stevemark
Joined: 29 Apr 2011 Posts: 3751 Location: Switzerland
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Posted: Tue Sep 24, 2019 8:07 pm Post subject: |
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stevemark wrote:
walter g wrote: |
Stephan,
I have a collection of MC X lenses and like them all. This lens seems to drop into focus really easy, which seems to be a trait of some but not all Minolta lenses.
I also have the 28mm f2.5, but unfortunately both of my copies are yellowed and need treatment. It's amazing the image quality difference between different levels of yellowing. |
I'd guess for classical (analogue) b/w landscapes the yellow MC 2.5/28mm would be better ... but of course for digital color photography it's better to have a "bleached" sample. Ten years ago i put my MC-X simply on my kitchen window board (outside, of course), the back side of the lens exposed towards the sun. Two or three weeks were sufficient. To protect the lens barrel from too much heat, I put a larger aluminum foil in front of the lens barrel. To expose the backside lens to sunlight, there was an opening of about 2 cm in the foil (including UV rays).
Stephan _________________ www.artaphot.ch |
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koji
Joined: 21 Jul 2008 Posts: 2106 Location: Hiroshima, Japan
Expire: 2012-12-27
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Posted: Tue Sep 24, 2019 11:44 pm Post subject: |
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koji wrote:
koji wrote: |
Buy one of these to de-yellow those lenses. |
That looks like the right size for most radioactive lenses, and it bombards from multiple directions. Nice.
Does it come colors other than pink?
You can get a WHITE one. Also you can put two lenses in that lamp if they are not too large,
and your wife (if there) can use for her nail art too. Take off rubber grip if lens has one before use. _________________ Our Home Page has 18,200 photos in 575 directories today.
Lenses: https://www.pbase.com/kkawakami/top_level_my_lenses |
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Sciolist
Joined: 29 Mar 2017 Posts: 1445 Location: Scotland
Expire: 2021-04-16
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Posted: Wed Sep 25, 2019 8:14 am Post subject: |
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Sciolist wrote:
koji wrote: |
Take off rubber grip if lens has one before use. |
Is there a specific reason for this koji? Say an effect on the service life of any elastomers used in the construction of the lens, or is it just so the lens fits better? |
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koji
Joined: 21 Jul 2008 Posts: 2106 Location: Hiroshima, Japan
Expire: 2012-12-27
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Posted: Wed Sep 25, 2019 1:36 pm Post subject: |
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koji wrote:
I am saying that rubber grip for focusing ring should be removed before UV-A radiation
for de-yellong process of a lens if it has a rubber grip. Just be cautious for radiation on rubber,
do not have any scientific reason though. _________________ Our Home Page has 18,200 photos in 575 directories today.
Lenses: https://www.pbase.com/kkawakami/top_level_my_lenses |
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Sciolist
Joined: 29 Mar 2017 Posts: 1445 Location: Scotland
Expire: 2021-04-16
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Posted: Wed Sep 25, 2019 1:38 pm Post subject: |
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Sciolist wrote:
koji wrote: |
I am saying that rubber grip for focusing ring should be removed before UV-A radiation
for de-yellong process of a lens if it has a rubber grip. Just be cautious for radiation on rubber,
do not have any scientific reason though. |
Thanks. |
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Antoine
Joined: 08 Jan 2016 Posts: 298 Location: London
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Posted: Wed Sep 25, 2019 5:23 pm Post subject: |
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Antoine wrote:
Rubber is always heavily stabilised with antioxidants. Exposing it to high intensity light reduces its lifetime (consumes the anti oxidant. Always safe to avoid it although test would be needed to measure effect. _________________ Antoine
Sony A6000 APS-C and Sony A7 Rii
Minolta Fisheye MD Rokkor 7.5 mm f4, Fisheye MD 16 f2.8 MD R 17mm f4, MD R 20mm f2.8, MC VFC & MDIII 24mm f2.8, MD 28mm f2.0 &3.5, MD II 35mm 1.8, MD 45mm f2.0, MD 50mm f 1.2 & MD I f1.4, MC PG 58mm 1.2, MD 85mm f2.0, MD R 85mm f2.8 Varisoft, MC 85mm f1.7 MD R 100mm f2.5, MD R 100mm f4.0 macro, MD III 135mm f2.8, MD R 200mm f2.8 & 4.0, RF 250mm f5.6, MD 300mm f4.5, MD APO 400 mm f5.6, RF 500mm f8.0, RF 800mm f8.0 *2 300-s and 300-l
100 mm f4 macro bellows (5/4)
Vivitar 17mm f3.5, Elicar 300mm mirror f5.6, Zhongi turbo ii
Sigma 16mm f 2.8 fish eye
Zooms:24-50 mm f4, 35-70 mm f3.5 macro, 28-85mm f3.5-4.5, 50-135 f 3.5, 70-210 f4 and MD APO 100-500 mm f8 |
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uddhava
Joined: 22 Aug 2012 Posts: 3071 Location: Hungary
Expire: 2021-06-21
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Posted: Thu Sep 26, 2019 11:28 am Post subject: |
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uddhava wrote:
Canon Macro Lens FD 100mm 1:4 |
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wolfhansen
Joined: 06 Oct 2013 Posts: 511 Location: Germany, Ruhr Area
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Posted: Thu Sep 26, 2019 8:31 pm Post subject: |
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wolfhansen wrote:
Leica R6.2 (1993) mit Elmarit-R 2.8/135mm (1973) _________________ Greets
Wolfgang |
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KEO
Joined: 27 Sep 2018 Posts: 756 Location: USA
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Posted: Thu Sep 26, 2019 8:36 pm Post subject: |
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KEO wrote:
This fell into my path the other day - a 200mm TELE Vivitar f/3.5 in M42:
It's got 18 aperture blades...
The outside is scarred up from use, but the glass is excellent, as are the mechanical functions.
I need to shoot with it more, but my initial impressions are very positive. I have a Pentacon 200, a Meyer Orestegor 200 zebra, a 200 Takumar 3.5, and a 200 Auto Tele Lentar 3.5 to compare it to. I used the Takumar a couple weeks ago, so I remember it better than the others.
It seems to be quite sharp wide open - slightly better than my Takumar, I would say. Bokeh is close to the Takumar, maybe not quite as good, but of course the Takumar has even more aperture blades!
It's about the same size and slightly heavier than the Orestegor, though the Vivitar has a 67mm front thread compared to the Pentacon/Orestegor's 55mm thread.
The lens looks somewhat awkward and unbalanced because the body near the mount is very narrow, while the front is large. It resembles a plunger. Once it's mounted on a camera though, the body balances out the entire form. I think it looks quite cool, actually.
wolfhansen wrote: |
Leica R6.2 (1993) mit Elmarit-R 2.8/135mm (1973) |
Fancy! |
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