Lens hood for 6x7 75mm Shift ?

klaus123 · 02-15-2022, 09:30 AM

Hello

Just got this lens and ask myselfe whether the lens hood form the ordenary 75/4.5 would interfere with the field of view (I do not see clear impact in the WLF)?
Or is it better to use the lens hood form 45/4 which fits too?

Does anyone have experiences on the lens hood usage on this lens?

2nd question: The manual says stop down to 8 or 11 - any other experience here?

**gofour3** · 02-15-2022, 10:22 AM

Originally posted by klaus123

Hello

Just got this lens and ask myselfe whether the lens hood form the ordenary 75/4.5 would interfere with the field of view (I do not see clear impact in the WLF)?
Or is it better to use the lens hood form 45/4 which fits too?

Does anyone have experiences on the lens hood usage on this lens?

2nd question: The manual says stop down to 8 or 11 - any other experience here?

There is no lens hood for the 67 75/4.5 shift lens, as a hood would interfere with the shifted image.

If you are not shifting this lens, then you can use the hood from the regular 67 75/4.5 lens. This works fine and I have tested it.

Yes you should always stop down to f8-f11 when shifting.

Note I have only used this lens on a P6x7/67 and 67II.

Phil.

desertscape · 02-16-2022, 11:52 AM - **1 Like**

Shifting moves the lens a bit further from the film plane, so the DOF scale is not as accurate as when the lens is unshifted. So, it's best to stop down a bit further than what the DOF scale would suggest. So if your DOF scale says 20 feet to infinity will be in focus when at f/8, it would be best to stop down another stop or 2 to be safe.

scrufftie · 05-30-2023, 01:09 AM

Originally posted by klaus123

Hello

Just got this lens and ask myselfe whether the lens hood form the ordenary 75/4.5 would interfere with the field of view (I do not see clear impact in the WLF)?
Or is it better to use the lens hood form 45/4 which fits too?

Does anyone have experiences on the lens hood usage on this lens?

2nd question: The manual says stop down to 8 or 11 - any other experience here?

Coming to this late, as I have a 75mm shift on its way to me. Did you solve your need for a lens hood?

I thought I would try the hood for the normal 75mm lens. A hood wouldn't interfere with the image when shifting as it moves with the lens front element. Every other shift lens I have owned has had a hood and I can shift with my 4x5 whilst suing a hood quite happily.

**kaseki** · 05-30-2023, 05:26 AM

Originally posted by scrufftie

Coming to this late, as I have a 75mm shift on its way to me. Did you solve your need for a lens hood?

I thought I would try the hood for the normal 75mm lens. A hood wouldn't interfere with the image when shifting as it moves with the lens front element. Every other shift lens I have owned has had a hood and I can shift with my 4x5 whilst suing a hood quite happily.

I think that the extreme objective lens rays when the lens assembly is coaxial with the focal plane (unshifted) are not the extreme rays when shifted. So a hood that passes extreme coaxial rays might block extreme shifted rays and some cuts into the upper part of the hood might be needed to minimize vignetting.

scrufftie · 05-30-2023, 05:47 AM

Originally posted by klaus123

Hello

Just got this lens and ask myselfe whether the lens hood form the ordenary 75/4.5 would interfere with the field of view (I do not see clear impact in the WLF)?
Or is it better to use the lens hood form 45/4 which fits too?

Does anyone have experiences on the lens hood usage on this lens?

2nd question: The manual says stop down to 8 or 11 - any other experience here?

In terms of stopping down, don't forget that at maximum shift you are using the edge of the image circle and, therefore, more of the 'edge' of the lens than you would normally. This is the softest part of the image at maximum aperture so stopping down a couple of stops is important where maximum image quality is required.

---------- Post added 05-30-23 at 05:50 AM ----------

Originally posted by kaseki

I think that the extreme objective lens rays when the lens assembly is coaxial with the focal plane (unshifted) are not the extreme rays when shifted. So a hood that passes extreme coaxial rays might block extreme shifted rays and some cuts into the upper part of the hood might be needed to minimize vignetting.

The hood needs to be a bit wider than the designated focal length would imply, given the larger image circle, which is what you're saying, I think. I have ordered a 3D printed hood which purports to be lens specific, so we'll see.

**gofour3** · 05-30-2023, 08:23 AM

As previously mentioned you can use the hood for the regular 75/4.5 when not shifting. No hood is used when shifting, using a P67 camera.

Phil.

desertscape · 05-31-2023, 05:11 PM

The general requirement of stopping down to f/8 or 11 when shifting doesn't mean that you cannot use smaller stops like f/22 and f/32. They work fine with this lens as well.

This lens was designed to be used off axis and is the reason why so many more lens elements are used in it, than in the regular 75mm.

Silent Street · 06-01-2023, 04:47 PM

Originally posted by desertscape

The general requirement of stopping down to f/8 or 11 when shifting doesn't mean that you cannot use smaller stops like f/22 and f/32. They work fine with this lens as well.

This lens was designed to be used off axis and is the reason why so many more lens elements are used in it, than in the regular 75mm.

...

Interesting anathema to the way Canon's TS-E lenses work (specifically the 24mm f3.5L, in the landscape context), where the function of extending depth of field is one accomplished using tilt and not aperture, nothwithstanding that any amount of shift can be added in. Effectively, an Av of f5.6 can be used with a calculated tilt value (mathematical, in degrees, or visually by field-approximation) to extend the DofF from near to far in one distinct 'peg'. This is the same methodology with Nikon's tilt-shift offerings. I have always been of the opinion that the Pentax 67 system is hobbled by the absence of a lens that offers not just shift — which is very limited in its application, but shift and tilt also, to greatly expand the application possibilities.

How is the 67 75mm affected by diffraction at f22? When the lens is shifted, is the TTL meter able to accommodate an accurate reading (as the P67 does not have an AEL to lock the meter reading before shifting)?

The other thing that perplexes me in this thread is that a lens hood interferes with the shift function? How, why or when does this interference occur if the hood moves with the lens (as a fixed accessory)?

klaus123 · 06-01-2023, 10:34 PM

For the defraction I have not tested it, but taking in account that a K1/36MP starts defraction arround f11 and all focal lengt and aperture related things to the 6x7 are multiplied by a factor of ~2 this shoud not be a real issue at f22. f32 may be a starting issue but resolution of film ist usually below the K1-resolution.

The lens comes w/o lens hood, bit the hood from the 40/f4 works fine in shifted positions.

This lens was delveloped in a time when the 6x7 was manual only. Manual of the lens says that you should measure and set exposure first and shift aftewards. THis can be done in manual mod on a 67II the same way.

Silent Street · 06-02-2023, 12:09 AM

Originally posted by klaus123

For the defraction I have not tested it, but taking in account that a K1/36MP starts defraction arround f11 and all focal lengt and aperture related things to the 6x7 are multiplied by a factor of ~2 this shoud not be a real issue at f22. f32 may be a starting issue but resolution of film ist usually below the K1-resolution.

The lens comes w/o lens hood, bit the hood from the 40/f4 works fine in shifted positions.

This lens was delveloped in a time when the 6x7 was manual only. Manual of the lens says that you should measure and set exposure first and shift aftewards. THis can be done in manual mod on a 67II the same way.

I surmise that the addition of an AEL facility on the 67ii specifically, makes that a more appropriate camera to use with a shift, or tilt + shift lens. The reason is, taking the methodology of Canon's TS-E lenses as a method example, metering is carried out with all movements in zeroed. The scene or subject is metered first, and exposure noted, then AEL used to hold the reading, with shift (or tilt +/- shift) then applied as a final step, and the exposure is made. Effectively, using AEL, the meter is reading the scene free of distortion/skewing caused by the lens being off-axis (shift applied). I cannot see this being particularly reliable or suitable with the 67's TTL meter, moreso in the absence of an AEL facility (Pentax 6x7, Pentax 67 cameras), but it certainly is possible with the 67ii, and with the older cameras, by employing a separate hand-held exposure meter to completely bypass the camera's meter.

scrufftie · 06-03-2023, 07:37 AM

According to the lens manual, you should compensate at full shift by an additional stop of exposure. Of course, with TTL you shouldn't need to compensate.

desertscape · 06-03-2023, 09:48 AM

This lens performs very well at f/22, both in shifted and unshifted modes. This lens is very useful for landscapes in the unshifted mode at f/32 when objects near the camera need to be in focus, plus infinity also being in focus. The other 75 lenses suffer in this regard, as they only have f/22. I sold my 75 Takumar because of this limitation. The shift 75 does OK in sharpness at f/32 and is usable.

Silent Street · 06-04-2023, 09:16 PM

Originally posted by scrufftie

According to the lens manual, you should compensate at full shift by an additional stop of exposure. Of course, with TTL you shouldn't need to compensate.

This assumes the user has established the upper, midline and lower limit of compensation through trial and error. A whole roll of film will need to be committed, along with copious written notes for reference, to establish just how much compensation is required, and in what circumstances (e.g. the amount of shift, in mm); the more shift, the more light has to be skewed around to reach the TTL meter — and that is where things can come unstuck, as the distorted light path is not giving the TTL meter an honest representation of what is happening in front of the lens. This situation is common to all shift and/or tilt+shift optics (both Nikon and Canon make a critical point of it), where the reading must be taken first, then locked-in, and then the movement(s) applied. The willingness to experiment, make errors and learn from them is key to mastering any optic that can shift or tilt from its native axis.

02-15-2022, 09:30 AM	#1
klaus123 Senior Member Join Date: Apr 2011 Location: Germany Posts: 238	Lens hood for 6x7 75mm Shift ? Hello Just got this lens and ask myselfe whether the lens hood form the ordenary 75/4.5 would interfere with the field of view (I do not see clear impact in the WLF)? Or is it better to use the lens hood form 45/4 which fits too? Does anyone have experiences on the lens hood usage on this lens? 2nd question: The manual says stop down to 8 or 11 - any other experience here?

06-01-2023, 04:47 PM	#9
Silent Street Veteran Member Join Date: Nov 2011 Location: Castlemaine, Victoria, AUS Photos: Albums Posts: 1,151	Originally posted by desertscape The general requirement of stopping down to f/8 or 11 when shifting doesn't mean that you cannot use smaller stops like f/22 and f/32. They work fine with this lens as well. This lens was designed to be used off axis and is the reason why so many more lens elements are used in it, than in the regular 75mm. ... Interesting anathema to the way Canon's TS-E lenses work (specifically the 24mm f3.5L, in the landscape context), where the function of extending depth of field is one accomplished using tilt and not aperture, nothwithstanding that any amount of shift can be added in. Effectively, an Av of f5.6 can be used with a calculated tilt value (mathematical, in degrees, or visually by field-approximation) to extend the DofF from near to far in one distinct 'peg'. This is the same methodology with Nikon's tilt-shift offerings. I have always been of the opinion that the Pentax 67 system is hobbled by the absence of a lens that offers not just shift — which is very limited in its application, but shift and tilt also, to greatly expand the application possibilities. How is the 67 75mm affected by diffraction at f22? When the lens is shifted, is the TTL meter able to accommodate an accurate reading (as the P67 does not have an AEL to lock the meter reading before shifting)? The other thing that perplexes me in this thread is that a lens hood interferes with the shift function? How, why or when does this interference occur if the hood moves with the lens (as a fixed accessory)? Last edited by Silent Street; 06-01-2023 at 04:52 PM.

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02-15-2022, 10:22 AM	#2
gofour3 Site Supporter Join Date: Oct 2008 Location: Vancouver, Canada Posts: 8,091	Originally posted by klaus123 Hello Just got this lens and ask myselfe whether the lens hood form the ordenary 75/4.5 would interfere with the field of view (I do not see clear impact in the WLF)? Or is it better to use the lens hood form 45/4 which fits too? Does anyone have experiences on the lens hood usage on this lens? 2nd question: The manual says stop down to 8 or 11 - any other experience here? There is no lens hood for the 67 75/4.5 shift lens, as a hood would interfere with the shifted image. If you are not shifting this lens, then you can use the hood from the regular 67 75/4.5 lens. This works fine and I have tested it. Yes you should always stop down to f8-f11 when shifting. Note I have only used this lens on a P6x7/67 and 67II. Phil.

02-16-2022, 11:52 AM - 1 Like	#3
desertscape Pentaxian Join Date: Feb 2009 Location: Arizona Posts: 1,272	Shifting moves the lens a bit further from the film plane, so the DOF scale is not as accurate as when the lens is unshifted. So, it's best to stop down a bit further than what the DOF scale would suggest. So if your DOF scale says 20 feet to infinity will be in focus when at f/8, it would be best to stop down another stop or 2 to be safe.

05-30-2023, 01:09 AM	#4
scrufftie New Member Join Date: May 2023 Posts: 3	Originally posted by klaus123 Hello Just got this lens and ask myselfe whether the lens hood form the ordenary 75/4.5 would interfere with the field of view (I do not see clear impact in the WLF)? Or is it better to use the lens hood form 45/4 which fits too? Does anyone have experiences on the lens hood usage on this lens? 2nd question: The manual says stop down to 8 or 11 - any other experience here? Coming to this late, as I have a 75mm shift on its way to me. Did you solve your need for a lens hood? I thought I would try the hood for the normal 75mm lens. A hood wouldn't interfere with the image when shifting as it moves with the lens front element. Every other shift lens I have owned has had a hood and I can shift with my 4x5 whilst suing a hood quite happily.

05-30-2023, 05:26 AM	#5
kaseki Loyal Site Supporter Join Date: Dec 2017 Photos: Gallery \| Albums Posts: 1,138	Originally posted by scrufftie Coming to this late, as I have a 75mm shift on its way to me. Did you solve your need for a lens hood? I thought I would try the hood for the normal 75mm lens. A hood wouldn't interfere with the image when shifting as it moves with the lens front element. Every other shift lens I have owned has had a hood and I can shift with my 4x5 whilst suing a hood quite happily. I think that the extreme objective lens rays when the lens assembly is coaxial with the focal plane (unshifted) are not the extreme rays when shifted. So a hood that passes extreme coaxial rays might block extreme shifted rays and some cuts into the upper part of the hood might be needed to minimize vignetting.

05-30-2023, 05:47 AM	#6
scrufftie New Member Join Date: May 2023 Posts: 3	Originally posted by klaus123 Hello Just got this lens and ask myselfe whether the lens hood form the ordenary 75/4.5 would interfere with the field of view (I do not see clear impact in the WLF)? Or is it better to use the lens hood form 45/4 which fits too? Does anyone have experiences on the lens hood usage on this lens? 2nd question: The manual says stop down to 8 or 11 - any other experience here? In terms of stopping down, don't forget that at maximum shift you are using the edge of the image circle and, therefore, more of the 'edge' of the lens than you would normally. This is the softest part of the image at maximum aperture so stopping down a couple of stops is important where maximum image quality is required. ---------- Post added 05-30-23 at 05:50 AM ---------- Originally posted by kaseki I think that the extreme objective lens rays when the lens assembly is coaxial with the focal plane (unshifted) are not the extreme rays when shifted. So a hood that passes extreme coaxial rays might block extreme shifted rays and some cuts into the upper part of the hood might be needed to minimize vignetting. The hood needs to be a bit wider than the designated focal length would imply, given the larger image circle, which is what you're saying, I think. I have ordered a 3D printed hood which purports to be lens specific, so we'll see.

05-30-2023, 08:23 AM	#7
gofour3 Site Supporter Join Date: Oct 2008 Location: Vancouver, Canada Posts: 8,091	As previously mentioned you can use the hood for the regular 75/4.5 when not shifting. No hood is used when shifting, using a P67 camera. Phil.

05-31-2023, 05:11 PM	#8
desertscape Pentaxian Join Date: Feb 2009 Location: Arizona Posts: 1,272	The general requirement of stopping down to f/8 or 11 when shifting doesn't mean that you cannot use smaller stops like f/22 and f/32. They work fine with this lens as well. This lens was designed to be used off axis and is the reason why so many more lens elements are used in it, than in the regular 75mm.

06-01-2023, 10:34 PM	#10
klaus123 Senior Member Join Date: Apr 2011 Location: Germany Posts: 238 Original Poster	For the defraction I have not tested it, but taking in account that a K1/36MP starts defraction arround f11 and all focal lengt and aperture related things to the 6x7 are multiplied by a factor of ~2 this shoud not be a real issue at f22. f32 may be a starting issue but resolution of film ist usually below the K1-resolution. The lens comes w/o lens hood, bit the hood from the 40/f4 works fine in shifted positions. This lens was delveloped in a time when the 6x7 was manual only. Manual of the lens says that you should measure and set exposure first and shift aftewards. THis can be done in manual mod on a 67II the same way.

06-02-2023, 12:09 AM	#11
Silent Street Veteran Member Join Date: Nov 2011 Location: Castlemaine, Victoria, AUS Photos: Albums Posts: 1,151	Originally posted by klaus123 For the defraction I have not tested it, but taking in account that a K1/36MP starts defraction arround f11 and all focal lengt and aperture related things to the 6x7 are multiplied by a factor of ~2 this shoud not be a real issue at f22. f32 may be a starting issue but resolution of film ist usually below the K1-resolution. The lens comes w/o lens hood, bit the hood from the 40/f4 works fine in shifted positions. This lens was delveloped in a time when the 6x7 was manual only. Manual of the lens says that you should measure and set exposure first and shift aftewards. THis can be done in manual mod on a 67II the same way. I surmise that the addition of an AEL facility on the 67ii specifically, makes that a more appropriate camera to use with a shift, or tilt + shift lens. The reason is, taking the methodology of Canon's TS-E lenses as a method example, metering is carried out with all movements in zeroed. The scene or subject is metered first, and exposure noted, then AEL used to hold the reading, with shift (or tilt +/- shift) then applied as a final step, and the exposure is made. Effectively, using AEL, the meter is reading the scene free of distortion/skewing caused by the lens being off-axis (shift applied). I cannot see this being particularly reliable or suitable with the 67's TTL meter, moreso in the absence of an AEL facility (Pentax 6x7, Pentax 67 cameras), but it certainly is possible with the 67ii, and with the older cameras, by employing a separate hand-held exposure meter to completely bypass the camera's meter.

06-03-2023, 07:37 AM	#12
scrufftie New Member Join Date: May 2023 Posts: 3	According to the lens manual, you should compensate at full shift by an additional stop of exposure. Of course, with TTL you shouldn't need to compensate.

06-04-2023, 09:16 PM	#14
Silent Street Veteran Member Join Date: Nov 2011 Location: Castlemaine, Victoria, AUS Photos: Albums Posts: 1,151	Originally posted by scrufftie According to the lens manual, you should compensate at full shift by an additional stop of exposure. Of course, with TTL you shouldn't need to compensate. This assumes the user has established the upper, midline and lower limit of compensation through trial and error. A whole roll of film will need to be committed, along with copious written notes for reference, to establish just how much compensation is required, and in what circumstances (e.g. the amount of shift, in mm); the more shift, the more light has to be skewed around to reach the TTL meter — and that is where things can come unstuck, as the distorted light path is not giving the TTL meter an honest representation of what is happening in front of the lens. This situation is common to all shift and/or tilt+shift optics (both Nikon and Canon make a critical point of it), where the reading must be taken first, then locked-in, and then the movement(s) applied. The willingness to experiment, make errors and learn from them is key to mastering any optic that can shift or tilt from its native axis.