[Brightcolours]

[quote name='Yakim' timestamp='1281610061' post='1704']

Not so.



http://www.naturfotograf.com/85ts_review.html



"Long awaited, my 85 mm f/2.8 tilt/shift Nikkor finally arrived yesterday."



"As delivered, the 85 PC has its shift and tilt movements orientated at right angles."



etc.







Extension tubes can be mounted on most lenses - 85/2.8 PC included - however I don't like using them. They rob you of too much light. That's why the only extension tube I have is the 12mm one. I had a whole Kenko set but rarely used the longer tubes. That's also why I prefer to work with lenses that inherently have as big magnification ratio as possible.

[/quote]

Lenses that focus closer also "rob you of light".... Macro lenses can lose more than 2 stops at MFD.

[wim]

Hi Yakim,

[quote name='Yakim' timestamp='1281610061' post='1704']

Not so.



[url="http://www.naturfotograf.com/85ts_review.html"]http://www.naturfoto...5ts_review.html[/url]



"Long awaited, my 85 mm f/2.8 tilt/shift Nikkor finally arrived yesterday."



"As delivered, the 85 PC has its shift and tilt movements orientated at right angles."



etc.

[/quote]

Thanks for that info! Never too old to learn <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />.

Extension tubes can be mounted on most lenses - 85/2.8 PC included - however I don't like using them. They rob you of too much light. That's why the only extension tube I have is the 12mm one. I had a whole Kenko set but rarely used the longer tubes. That's also why I prefer to work with lenses that inherently have as big magnification ratio as possible.

Actually, close focusing robs one of as much light as extension tubes do, at the same magnification anyway, as this is directly related to magnification, and nothing else. This is even true with close-up lenses, although it isn't as obvious with those, due to the shortening of the FL they cause for the system as a whole <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />.



The amount of light you lose is exactly the same at the same magnification, whatever lens you use.



Kind regards, Wim

[ragsnoldiron]

[quote name='Yakim' timestamp='1281563195' post='1690']

Thank you very much for the offer. I'm looking for both at still life subjects but mainly at landscape pictures, with and without 12mm tube. Both with tilt. I have enough non-moving lenses.



BTW, do you have the Mk I or Mk II?

[/quote]



I will create a few images on Saturday the 14th and put the RAW up so you can have a look. I have the second version, and don't care for either the first version or the 45 for a few reasons, but mainly CA. There is a comparison between the Nikon 85 and Canon 90 on LLoyd Chambers site. The main difference between Nikon versions is the older style has much greater shift movement than both the new model and the Canon. His test were with a D3x and 5D mk II and the Canon 90 clearly had less chromatic aberration with movements (though Nikon cameras auto correct this and he gives examples), less vignetting (mostly because of smaller movements I think), and was overall sharper across the frame at larger apertures than the Nikon (but again less movement and Nikon was very sharp too). I thought of buying the Nikon too for the macro, but the Canon suits me fine with tubes and I have a lot to learn with it yet, though I like the option of putting Nikon lenses on Canon bodies. Check back Saturday and I will give a link to an area where you can download the RAW images with the 24 II, 12mm tube, from a 5D II body.

[Yakim]

[quote name='wim' timestamp='1281614078' post='1712']

Hi Yakim,



Thanks for that info! Never too old to learn <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />.



Actually, close focusing robs one of as much light as extension tubes do, at the same magnification anyway, as this is directly related to magnification, and nothing else. This is even true with close-up lenses, although it isn't as obvious with those, due to the shortening of the FL they cause for the system as a whole <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />.



The amount of light you lose is exactly the same at the same magnification, whatever lens you use.



Kind regards, Wim

[/quote]



With all due respect, I seriously doubt that.



http://photo.net/canon-eos-digital-camera-forum/00Wuji

[Yakim]

[quote name='Symple' timestamp='1281626408' post='1718']

I will create a few images on Saturday the 14th and put the RAW up so you can have a look. I have the second version, and don't care for either the first version or the 45 for a few reasons, but mainly CA. There is a comparison between the Nikon 85 and Canon 90 on LLoyd Chambers site. The main difference between Nikon versions is the older style has much greater shift movement than both the new model and the Canon. His test were with a D3x and 5D mk II and the Canon 90 clearly had less chromatic aberration with movements (though Nikon cameras auto correct this and he gives examples), less vignetting (mostly because of smaller movements I think), and was overall sharper across the frame at larger apertures than the Nikon (but again less movement and Nikon was very sharp too). I thought of buying the Nikon too for the macro, but the Canon suits me fine with tubes and I have a lot to learn with it yet, though I like the option of putting Nikon lenses on Canon bodies. Check back Saturday and I will give a link to an area where you can download the RAW images with the 24 II, 12mm tube, from a 5D II body.

[/quote]



No need for RAW. JPEG will suffice as I'm only interested in a general impression of what it can do.



Thanks again.

[Brightcolours]

[quote name='Yakim' timestamp='1281703072' post='1741']

With all due respect, I seriously doubt that.



http://photo.net/canon-eos-digital-camera-forum/00Wuji

[/quote]

Nice that you "seriously doubt that", however it sort of is true. Of course, because of the many different aspects at play, results "may" differ slightly, it still is true that it does not matter in your case.



Whether you use the excellent Canon TS-E 90mm f2.8 with an extension tube, or the slightly less excellent Nikon 85mm f2.8 PC D, the light loss at the same distance will be more or less the same with each setup.



Point being: It is not the extension tubes which make you lose light, it is the close up focussing that extension tubes cause.



The discussion you linked to does not tell much... you did not actually measure the exposure for real, nor do we know how much the focal length changes per lens, for instance.

[wim]

[quote name='Yakim' timestamp='1281703072' post='1741']

With all due respect, I seriously doubt that.



[url="http://photo.net/canon-eos-digital-camera-forum/00Wuji"]http://photo.net/can...ra-forum/00Wuji[/url]

[/quote]

The concept is simple: at 1:1 the area of the image circle the lens projects is 4X the size of the image circle at 1:1. Provided lighting is constant, at the same aperture the loss of light is therefore equal to 75%, as the same amount or light is shared over four times the area. IOW, th ecropped image used for the 1:1 shot on yoru sensor, now only recieves 1/4 odf th elight the sensor received at infinity., or a loss of 2 stops of light.



It is a simple, physical given, i.e., it's a law of physics. Optics 101.



If you therefore get different results with different lenses, their has to be something different at play, no more, no less.



Kind regards, Wim

[wim]

[quote name='Brightcolours' timestamp='1281708452' post='1745']

Nice that you "seriously doubt that", however it sort of is true. Of course, because of the many different aspects at play, results "may" differ slightly, it still is true that it does not matter in your case.



Whether you use the excellent Canon TS-E 90mm f2.8 with an extension tube, or the slightly less excellent Nikon 85mm f2.8 PC D, the light loss at the same distance will be more or less the same with each setup.



Point being: It is not the extension tubes which make you lose light, it is the close up focussing that extension tubes cause.



The discussion you linked to does not tell much... you did not actually measure the exposure for real, nor do we know how much the focal length changes per lens, for instance.

[/quote]

It's actually not "sort of true", its a law of physics, and therefore true for the world we live in, as it is built according to the same set of physical laws this is part of.. Focal length actually has nothing to do with this, see my reply to Yakim.



Kind regards, Wim

[Brightcolours]

[quote name='wim' timestamp='1281735894' post='1759']

It's actually not "sort of true", its a law of physics, and therefore true for the world we live in, as it is built according to the same set of physical laws this is part of.. Focal length actually has nothing to do with this, see my reply to Yakim.



Kind regards, Wim

[/quote]

You are reading very defensively. I said it is soft of true that light fall off is exactly the same with all lenses, and I am correct in that, I even pointed out that there can be many factors at play (including the focal length changing differently with different lenses, which does influence exposure too... if the focal length changes but the aperture stays the same).

[wim]

[quote name='Brightcolours' timestamp='1281776056' post='1762']

You are reading very defensively. I said it is soft of true that light fall off is exactly the same with all lenses, and I am correct in that, I even pointed out that there can be many factors at play (including the focal length changing differently with different lenses, which does influence exposure too... if the focal length changes but the aperture stays the same).

[/quote]

This wasn't meant defensive at all, but considering Yakim's reply I just wanted to make sure that it was clear that it actually is an exact thing, and anything found that seems to differ, must therefore be caused by other factors. FL changes do not make a difference, apparent light loss is purely about the magnification factor.



Sincere apologies if I upset you, that certainly was not the intention.



Kindest regards, Wim