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kyrcy
Joined: 23 Feb 2015
Posts: 124
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 Posted: Wed Feb 25, 2015 1:58 am Post subject: Opinions about lenses |
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kyrcy wrote:
Is anyone using the following (M42) lenses?
1) Vivitar (Kiron?) Close Focusing 70-150mm f/3.8 Auto Zoom (two rings version)
2) Computar 35mm f/2.8 (JAPAN)
I am interested in infinity focus (preferably matching the lens distance scale when used with an adapter) and good performance at or near full aperture (for low light usage). |
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luisalegria
Joined: 07 Mar 2008
Posts: 6627
Location: San Francisco, USA
Expire: 2018-01-18
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| Posted: Wed Feb 25, 2015 4:12 am Post subject: |
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luisalegria wrote:
1. Yes. Yes it is Kiron.
Don't trust the distance scale on any of these zooms.
If the scale is important to you, verify the exact infinity focus and mark it.
Good performance is relative to your requirements. It was sharp enough for me, but without understanding your needs nobody can say much more.
There are sharper f/3.5 tele lenses.
2. Don't know. Be even more careful of infinity focus with wide angles.
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I like Pentax DSLR's, Exaktas, M42 bodies of all kinds, strange and cheap Japanese lenses, and am dabbling in medium format/Speed Graphic work. |
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kyrcy
Joined: 23 Feb 2015
Posts: 124
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| Posted: Wed Feb 25, 2015 6:03 pm Post subject: |
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kyrcy wrote:
I am interested in astrophotography which can be demanding as a lens should be able to deliver sharp star images to the edge of the field without distortions and to focus to infinity perfectly. The few manual lenses I have used with an adapter still focus to infinity at the distance scale mark so I don’t have to deal with focusing. I would be happy to find more lenses capable of doing this. |
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luisalegria
Joined: 07 Mar 2008
Posts: 6627
Location: San Francisco, USA
Expire: 2018-01-18
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| Posted: Wed Feb 25, 2015 6:17 pm Post subject: |
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luisalegria wrote:
Astrophotography is its own specialty and the requirements don't always apply to general photography, so you may be better off asking the astronomy guys out there.
You have been lucky with MF lenses, but its very common for a lens to be defective in this setting. You will usually find tele lenses focus beyond infinity (and this may have been deliberately set at the factory), and wide angles just short of infinity. And this will vary from lens to lens. Its sometimes easy to adjust, sometimes not.
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I like Pentax DSLR's, Exaktas, M42 bodies of all kinds, strange and cheap Japanese lenses, and am dabbling in medium format/Speed Graphic work. |
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iangreenhalgh1
Joined: 18 Mar 2011
Posts: 15685
Expire: 2014-01-07
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| Posted: Wed Feb 25, 2015 7:54 pm Post subject: |
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iangreenhalgh1 wrote:
The Computar is a Kowa, uncommon item. I have the 2.8/28 version and it is very sharp in the centre but soft in the corners, I expect due to field curvature. It's therefore a good lens on APS-C but not so hot on full frame.
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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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visualopsins
Joined: 05 Mar 2009
Posts: 10532
Location: California
Expire: 2025-04-11
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| Posted: Wed Feb 25, 2015 10:12 pm Post subject: |
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visualopsins wrote:
| luisalegria wrote: |
| ... You will usually find tele lenses focus beyond infinity (and this may have been deliberately set at the factory), and wide angles just short of infinity. And this will vary from lens to lens. ... |
Rather wide angle lens infinity focus depends more on accurate adapter thickness -- a wide angle lens on an adapter that is too thick cannot achieve infinity focus, while a telephoto lens can... These do not vary from lens to lens, unless the lens is not calibrated properly or has other problems.
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☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ like attracts like! ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮
Cameras: Sony ILCE-7RM2, Spotmatics II, F, and ESII, Nikon P4
Lenses:
M42 Asahi Optical Co., Takumar 1:4 f=35mm, 1:2 f=58mm (Sonnar), 1:2.4 f=58mm (Heliar), 1:2.2 f=55mm (Gaussian), 1:2.8 f=105mm (Model I), 1:2.8/105 (Model II), 1:5.6/200, Tele-Takumar 1:5.6/200, 1:6.3/300, Macro-Takumar 1:4/50, Auto-Takumar 1:2.3 f=35, 1:1.8 f=55mm, 1:2.2 f=55mm, Super-TAKUMAR 1:3.5/28 (fat), 1:2/35 (Fat), 1:1.4/50 (8-element), Super-Multi-Coated Fisheye-TAKUMAR 1:4/17, Super-Multi-Coated TAKUMAR 1:4.5/20, 1:3.5/24, 1:3.5/28, 1:2/35, 1:3.5/35, 1:1.8/85, 1:1.9/85 1:2.8/105, 1:3.5/135, 1:2.5/135 (II), 1:4/150, 1:4/200, 1:4/300, 1:4.5/500, Super-Multi-Coated Macro-TAKUMAR 1:4/50, 1:4/100, Super-Multi-Coated Bellows-TAKUMAR 1:4/100, SMC TAKUMAR 1:1.4/50, 1:1.8/55
M42 Carl Zeiss Jena Flektogon 2.4/35
Contax Carl Zeiss Vario-Sonnar T* 28-70mm F3.5-4.5
Pentax K-mount SMC PENTAX ZOOM 1:3.5 35~105mm, SMC PENTAX ZOOM 1:4 45~125mm
Nikon Micro-NIKKOR-P-C Auto 1:3.5 f=55mm, NIKKOR-P Auto 105mm f/2.5 Pre-AI (Sonnar), Micro-NIKKOR 105mm 1:4 AI, NIKKOR AI-S 35-135mm f/3,5-4,5
Tamron SP 17mm f/3.5 (51B), Tamron SP 17mm f/3.5 (51BB), SP 500mm f/8 (55BB), SP 70-210mm f/3.5 (19AH)
Vivitar 100mm 1:2.8 MC 1:1 Macro Telephoto (Kiron)
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kyrcy
Joined: 23 Feb 2015
Posts: 124
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| Posted: Thu Feb 26, 2015 5:37 am Post subject: |
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kyrcy wrote:
I tried a "normal" and a telephoto lens using two different adapters and for both infinity focus matched the distance scale. I took some photos of the Moon and the night sky where infinity focus is critical and they were all well focused. |
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Laurentiu Cristofor
Joined: 23 Oct 2010
Posts: 524
Location: WA, USA
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| Posted: Tue Mar 03, 2015 2:49 am Post subject: |
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Laurentiu Cristofor wrote:
| kyrcy wrote: |
| I tried a "normal" and a telephoto lens using two different adapters and for both infinity focus matched the distance scale. I took some photos of the Moon and the night sky where infinity focus is critical and they were all well focused. |
You are lucky or have better adapters or what you think was well focused just appeared to be so. I have several lenses for which I cannot focus at infinity with my adapters.
Even with lenses that can focus at infinity, I found that the optimal setting when focusing on something like the Moon was usually just short of the infinity marking.
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kyrcy
Joined: 23 Feb 2015
Posts: 124
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| Posted: Wed Mar 04, 2015 5:20 am Post subject: |
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kyrcy wrote:
| Laurentiu Cristofor wrote: |
You are lucky or have better adapters or what you think was well focused just appeared to be so. I have several lenses for which I cannot focus at infinity with my adapters.
Even with lenses that can focus at infinity, I found that the optimal setting when focusing on something like the Moon was usually just short of the infinity marking. |
As I wrote above I took photos of the Moon and the night sky and they were focused. I don't think that these photos appeared to be in focus and they weren't, because they show details on the Moon and stars not visible to the naked eye. |
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visualopsins
Joined: 05 Mar 2009
Posts: 10532
Location: California
Expire: 2025-04-11
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| Posted: Thu Mar 05, 2015 12:59 am Post subject: |
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visualopsins wrote:
I think some folks are confusing "at the infinity mark" with "as far as the focus turns in that direction". As said telephotos are likely to focus beyond infinity, to allow focus when long metals expand and contract. Normal/wide infinity mark and focus stop the same is typical in my experience.
Adapter thickness is easy to measure with calipers...
_________________
☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ like attracts like! ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮
Cameras: Sony ILCE-7RM2, Spotmatics II, F, and ESII, Nikon P4
Lenses:
M42 Asahi Optical Co., Takumar 1:4 f=35mm, 1:2 f=58mm (Sonnar), 1:2.4 f=58mm (Heliar), 1:2.2 f=55mm (Gaussian), 1:2.8 f=105mm (Model I), 1:2.8/105 (Model II), 1:5.6/200, Tele-Takumar 1:5.6/200, 1:6.3/300, Macro-Takumar 1:4/50, Auto-Takumar 1:2.3 f=35, 1:1.8 f=55mm, 1:2.2 f=55mm, Super-TAKUMAR 1:3.5/28 (fat), 1:2/35 (Fat), 1:1.4/50 (8-element), Super-Multi-Coated Fisheye-TAKUMAR 1:4/17, Super-Multi-Coated TAKUMAR 1:4.5/20, 1:3.5/24, 1:3.5/28, 1:2/35, 1:3.5/35, 1:1.8/85, 1:1.9/85 1:2.8/105, 1:3.5/135, 1:2.5/135 (II), 1:4/150, 1:4/200, 1:4/300, 1:4.5/500, Super-Multi-Coated Macro-TAKUMAR 1:4/50, 1:4/100, Super-Multi-Coated Bellows-TAKUMAR 1:4/100, SMC TAKUMAR 1:1.4/50, 1:1.8/55
M42 Carl Zeiss Jena Flektogon 2.4/35
Contax Carl Zeiss Vario-Sonnar T* 28-70mm F3.5-4.5
Pentax K-mount SMC PENTAX ZOOM 1:3.5 35~105mm, SMC PENTAX ZOOM 1:4 45~125mm
Nikon Micro-NIKKOR-P-C Auto 1:3.5 f=55mm, NIKKOR-P Auto 105mm f/2.5 Pre-AI (Sonnar), Micro-NIKKOR 105mm 1:4 AI, NIKKOR AI-S 35-135mm f/3,5-4,5
Tamron SP 17mm f/3.5 (51B), Tamron SP 17mm f/3.5 (51BB), SP 500mm f/8 (55BB), SP 70-210mm f/3.5 (19AH)
Vivitar 100mm 1:2.8 MC 1:1 Macro Telephoto (Kiron)
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kyrcy
Joined: 23 Feb 2015
Posts: 124
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| Posted: Thu Mar 05, 2015 5:04 pm Post subject: |
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kyrcy wrote:
With the telephoto I am using the focus does not turn in that direction beyond the infinity mark. |
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