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The classic mechanical digital Hasselblad 503CWD

I wonder if the pentagons are present because the iris cann not be at the best place (the central shutter is allready there !) The typical case is the portrait with flash and dark background. But far away one wears black suits and... google .
One other case is the portrait with trees in the background. Between leafs a lot white pentagons aprears sharper dans leafs.
 
Isidor,

It really is the shape of the opening, not the position, that determines the shape of these blotches.
 
Simon, the lens was an 80mm with extention tube 32.

Q.G. " cannot be corrected:le"

It can be prevented by covering making sure the lens shade is covering the lens and light is not shining into it. Photoshop can remove this using the 'st& tool' though I have not had this pentagon effect through using sufficient shade over the lens.

Had a chat with a colleague today, who does advertising still life for some major clients in London, he has been using a 16MP digital camera (Phase One) with hasselblad for the past three years and explains this is all they need. This is a large company with a lot of turnover of work. It is a relief to know that such an experienced 10 x 8 studio camera photographer is back to using Hasselblads (500CX) for studio work. He is not the only one as he shares studios with five others all working on similar accounts.

There you go, who said the V system is on its way out.


All the best, Carl
 
Carl,

happy.gif
...
You can't prevent specular highlights in your subject occurring by using a shade.
These thingies - standing out, like specular highlights do - will show the shape of the aperture when not in focus.
In fact, any out of focus bit will show that shape: it's a 'law of nature' (it really is). You do need contrast for it to be apparent, and these (and other) highlights provide just that.
The shape of the aperture, and this effect, is/was used quite a bit in the printing industry, controlling dot shape when making screens.

But yes, you can prevent it happening by making sure the lens is covered so no light is coming through.
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Q.G. Yes you can! Make sure that there is no flare, no flare by using a shade, not just the standard shade but a 'French flag' and it will not happen. If there is flare visible on the lens this is when it will occur, otherwise why are we not getting it on every shot? mmmmm?
We were not talking about focus.
 
Carl,

Trust me: the pentagonal highlights in the watch shot cannot be prevented by using a shade, french flag, or any other thing.

And they are blurry specular highlights, not flare. Points in the subject that catch light and reflect it towards the camera.

Since they, obviously, are within the field of view, no shading device can take them out of the picture.
Unless that shading device is a properly seated lens cap. But that will not do, i guess...
wink.gif


Specular highlights - like any other bit of the image - will be projected on film they way they are... when in focus!
When not, they spread out in a blurry patch. That patch will always (it really is a law of nature) show the shape of the pencil of light forming the image, i.e. the shape of the aperture limiting the pencil of light, i.e. the shape of the aperture.

And so will all the other out of focus bits. They just lack the contrast: the many pentagonal blotches merge into one mass.

Do you know mirror-lenses?
Try avoiding the donut shaped blotches they produce using a french flag.
But don't hold your breath trying...
wink.gif
 
Marc, you took the bait........ I have been waiting for someone to jump in and mention it!

This is well known and the shot was not for a client. Important to note that on this website any photographs submitted can be used by the owner without copyright permission because that is the agreement of the sight.

If a perfect studio shot was submitted this could for what ever ie photo library shot.

So there is method behiind the madness! cheers;-)
 
QG, I am writing this from the hospital bed after holding my breath. I have used mirror lenses they give nice doughnuts in the highlights but that is because there is a solid structure in the centre of the lens. However, we may differ on this unless tests are done, these polygons are more apparent direct to sun for the contrast reason, may be we are talking about a different optic effect........all the best, Carl

ps Marc, the arifacts are a reflection of the camera and light box set. Left them in so that if anyone wanted to enlarge they could see what sort of shirt I was wearing. In similar situation as the Harley Davidson shot, if we zoom into the chrome cover on the bike we can see you holding the camers, cheers!
 
Carl,

The "solid structure in the centre of the lens" in a catadioptric thingy is no more than a thing that determines the shape of the aperture (annular, in stead of round).
And it has the expected effect ("but that is because there is ...") on the shape of out of focus blotches.

It is a wellknown fact. A law of nature.
We do not need tests. Trust me!
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Q.G. Ok.....otherwise we will have another hospital case! PS, never trust anyone who says trust me!

Marc, as they say the Devil is in the detail....... ;-)
 
Carl

Philosophical , when I say trust me , then you can realy trust me .
Truth is my base of life , and without that I could not live .
BTW , tomorrow I am going to visit a roadshow and I will have the new H3D31 in my hands .
Trust me ? ? ?
 
ha ha ha ha ha
You got it !
You broke the code !

Amazing when you recieve the velvia portrait's pictures with that in the back ground !
 
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