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charley5
Joined: 11 Feb 2020 Posts: 347 Location: India
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Posted: Sat May 15, 2021 2:16 pm Post subject: Tilt-Shift Adapters for Manual Portraits |
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charley5 wrote:
Hi Everyone:
I saw someone use a FotodioX Pro TLT ROKR Tilt-Shift Adapter for a Canon to Sony mount, with a Biotar 75mm at f1.8. I have this lens and also the Helios 85mm. One of the problems is that both these lenses, which have the same design, have a very limited circle of sharp focus, basically square in the middle, taking up about 15% of the image area. But this fellow was able to get sharp focus about 2/3 up the image, and he told me it was because of the tilt-shift adapter. I would imagine that he simply sifted the point of focus somewhat. So is this a good solution if I want to move the point of focus in my portraits, particularly since in many of my portraits the face is 2/3 way up?
I also heard that one could narrow or expand the point of focus with a shift-tilt adapter. I am more interested in expanding since I shoot close to wide open, and I would like to get greater depth of field while not compromising on the bokeh. Is this really possible? Can someone please comment on this?
Thanks,
-Charles |
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visualopsins
Joined: 05 Mar 2009 Posts: 10957 Location: California
Expire: 2025-04-11
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Posted: Sat May 15, 2021 3:01 pm Post subject: |
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visualopsins wrote:
In case you don't already know
https://www.cambridgeincolour.com/tutorials/tilt-shift-lenses1.htm
https://www.cambridgeincolour.com/tutorials/tilt-shift-lenses2.htm _________________ ☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮☮ 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-A 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 (151B), 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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charley5
Joined: 11 Feb 2020 Posts: 347 Location: India
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Posted: Sat May 15, 2021 3:46 pm Post subject: |
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charley5 wrote:
Yes, I know the basics, but applying it to the kind of portrait photography that i do was new to me. |
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DConvert
Joined: 12 Jun 2010 Posts: 921 Location: Essex UK
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Posted: Sat May 15, 2021 6:42 pm Post subject: Re: Tilt-Shift Adapters for Manual Portraits |
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DConvert wrote:
charley5 wrote: |
Hi Everyone:
I saw someone use a FotodioX Pro TLT ROKR Tilt-Shift Adapter for a Canon to Sony mount, with a Biotar 75mm at f1.8. I have this lens and also the Helios 85mm. One of the problems is that both these lenses, which have the same design, have a very limited circle of sharp focus, basically square in the middle, taking up about 15% of the image area. But this fellow was able to get sharp focus about 2/3 up the image, and he told me it was because of the tilt-shift adapter. I would imagine that he simply sifted the point of focus somewhat. So is this a good solution if I want to move the point of focus in my portraits, particularly since in many of my portraits the face is 2/3 way up?
I also heard that one could narrow or expand the point of focus with a shift-tilt adapter. I am more interested in expanding since I shoot close to wide open, and I would like to get greater depth of field while not compromising on the bokeh. Is this really possible? Can someone please comment on this?
Thanks,
-Charles |
There is no 'point of focus' it's a 'plane of focus' (the plane is not quite flat in many real lenses). Tilting the lens tilts the plane of focus this can put more of the sample in the plane of focus (or if tilting the other way less of the subject). Getting the tilt right to get focus as you want it can be quite challenging, especially if the lens concerned adds significant field curvature.
I assume you want to shoot wide open to keep the bokeh circular, but this is limiting you DOF excessively. For normal portraits I'm not convinced tiling the lens will help much as a standing subject is normally close to parallel to the sensor (things can be quite different if the subject is reclining). Using a circular bokeh mask to reduce the aperture should be able to give you more DOF without changing the nature of your bokeh.
Tilting to reduce DOF is much easier |
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Slalom
Joined: 10 Dec 2017 Posts: 158 Location: Stourbridge
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Posted: Sat May 15, 2021 9:52 pm Post subject: |
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Slalom wrote:
This is a guide I found for tilt use:
http://www.northlight-images.co.uk/using-lens-tilt-on-your-digital-slr/
I have a TLT ROKR on the way. |
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charley5
Joined: 11 Feb 2020 Posts: 347 Location: India
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Posted: Sun May 16, 2021 5:05 pm Post subject: Re: Tilt-Shift Adapters for Manual Portraits |
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charley5 wrote:
DConvert wrote: |
charley5 wrote: |
Hi Everyone:
I saw someone use a FotodioX Pro TLT ROKR Tilt-Shift Adapter for a Canon to Sony mount, with a Biotar 75mm at f1.8. I have this lens and also the Helios 85mm. One of the problems is that both these lenses, which have the same design, have a very limited circle of sharp focus, basically square in the middle, taking up about 15% of the image area. But this fellow was able to get sharp focus about 2/3 up the image, and he told me it was because of the tilt-shift adapter. I would imagine that he simply sifted the point of focus somewhat. So is this a good solution if I want to move the point of focus in my portraits, particularly since in many of my portraits the face is 2/3 way up?
I also heard that one could narrow or expand the point of focus with a shift-tilt adapter. I am more interested in expanding since I shoot close to wide open, and I would like to get greater depth of field while not compromising on the bokeh. Is this really possible? Can someone please comment on this?
Thanks,
-Charles |
There is no 'point of focus' it's a 'plane of focus' (the plane is not quite flat in many real lenses). Tilting the lens tilts the plane of focus this can put more of the sample in the plane of focus (or if tilting the other way less of the subject). Getting the tilt right to get focus as you want it can be quite challenging, especially if the lens concerned adds significant field curvature.
I assume you want to shoot wide open to keep the bokeh circular, but this is limiting you DOF excessively. For normal portraits I'm not convinced tiling the lens will help much as a standing subject is normally close to parallel to the sensor (things can be quite different if the subject is reclining). Using a circular bokeh mask to reduce the aperture should be able to give you more DOF without changing the nature of your bokeh.
Tilting to reduce DOF is much easier |
Thanks. I researched "circular bokeh mask" but only found information related to changing the shape of bokeh balls, such as heart-shaped. Can you point to more information on the subject of bokeh masks? |
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charley5
Joined: 11 Feb 2020 Posts: 347 Location: India
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Posted: Sun May 16, 2021 5:06 pm Post subject: |
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charley5 wrote:
thanks, very interesting, but lost me half way through with the technical parts! |
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DConvert
Joined: 12 Jun 2010 Posts: 921 Location: Essex UK
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Posted: Sun May 16, 2021 5:39 pm Post subject: Re: Tilt-Shift Adapters for Manual Portraits |
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DConvert wrote:
Thanks. I researched "circular bokeh mask" but only found information related to changing the shape of bokeh balls, such as heart-shaped. Can you point to more information on the subject of bokeh masks?[/quote]
as your investigations showed, Bokeh masks are simple shapes cut from an opaque material to give rise to an aperture of the shape desired. They are often used with elaborate shapes, but also work with circular cut outs, where they would be similar to waterhouse stops just fitted in front of the lens. as long as the shape is less than the size of the iris as seen from the front of the lens & the mask is tight up against the front element, it should work reasonably. I've used this approach when adapting projector lenses due to their lack of an aperture. I was thinking you could use this technique instead of the lenses iris if the aperture forms a shape not to your liking. |
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