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Arri BL Blimp question?


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#1 Mark Williams

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Posted 11 February 2006 - 11:01 AM

I have an Arri BL and have brought a T* Coated zoom lens..

I noticed the settings for opening the lens only go up to 3.3 on the blimp.. Whereas the settings on the new zeiss lens go up to 2.8 The settings seem to be fixed by the blimp thus preventing any movement of the zeiss lens to it full open position? Am I correct on this? Has anyone else found this? Does this mean I am not fully opening the zeiss lens? Its a bit hard to tell with the lens in and I dont want to remove it from the blimp.. It took forever to get it in there!

Also, and its annoying me ;) does anyone know how to remove the accessory handle from the accessory shoe? :blink:
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#2 Patrick Neary

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Posted 11 February 2006 - 11:16 AM

Hi- Probably the blimp is marked for the T-stop, so f2.8 (wide open) on the lens is t3.3 (also wide open). To get the handle off you pull the front round knob/button (on the base of the handle) straight out to release a pin and slide the handle up or down out of the shoe- hope that makes sense!
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#3 Mark Williams

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Posted 11 February 2006 - 02:54 PM

Hi- Probably the blimp is marked for the T-stop, so f2.8 (wide open) on the lens is t3.3 (also wide open). To get the handle off you pull the front round knob/button (on the base of the handle) straight out to release a pin and slide the handle up or down out of the shoe- hope that makes sense!


Hi Patrick thanks for the reply what Im saying though is the Blimp seems to be stopping the lens from openig fully down to f2.8 In fact it actually looks as if the lens has been opened to about f3.3.. Just wondered if ayone knows more from there experience.. It may be something IM doing wrong BUT I dont want to take the lens out of the Blimp I really had a nightmare getting it in and Im sure that was down to my ineptness.. I just dont want to risk the frustration I felt all over again.. And perhaps not even have a problem..

Thanks though :D
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#4 Brian Drysdale

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Posted 11 February 2006 - 04:33 PM

The confusion is due to the f stop and the T stop. The Zeiss 10 to 100 zoom lens has a f stop of 2.8, but the older models of the lens had a T stop of 3.3 (the later models had a T stop of 3.0).

For exposure the T stop factors in the transmission losses of the lens and so is more accurate setting. The 16 BL blimp has the T stop markings; the f stop itself is only useful for working out the depth of field.
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#5 Patrick Neary

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Posted 11 February 2006 - 10:09 PM

hmmm. is it possible you've put a newer zeiss lens into a blimp designed for the the older zeiss, or even an angenieux? I remember there being some kind of f or t-stop reference mark on the blimp (for lining things up when you mounted the lens in there) but that may have just been on the prime blimp. sorry to not be of much help!
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#6 Mitch Gross

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Posted 12 February 2006 - 12:30 AM

You can check without removing the lens from the blimp. Zoom in all the way. Open the aperture as wide as you can. Focus to infinity. Now turn the inching knob so that you can see nothing through the viewfinder. Shine a flashlight down the lens and look in--you should be looking at the film sitting in the gate. And you should be able to see the sides all around without the iris visible at all. Look through while turning the iris ring to see what it looks like. It should completely retract out of sight when wide open. If you can't tell from the from then you can pull lens & blimp intact from the camera and view from the rear of the lens.

You probably simply need to remark your blimp ring, which is no small feat if you cannot see where it aligns properly with the physical lens barrel.
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#7 Mark Williams

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Posted 12 February 2006 - 05:39 AM

Mitch
-------
Great Help ! STILL difficult to be sure..

BUT I noticed using the torch I could see through the plexiglass and down a bit.. So I can NOW line up the lens Markings.. THE FURTHEST it will go is T3..

At least now I know this is T3..

Shining the torch down the lens seems to confirm there is a very small bit of iris still showing in fact minscule It doesnt matter for me if I cant get down to T2.8... T3 Will do nicely..

Patrick
--------

Another great answer and I think you hit the nail on the head

Brian
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Go to the top of the class you got it right The markings on the lens only go to T3 So this probably is the lens glass capability (T Stop) and the f stop is f2.8 No doubt I may have gone astray here..


What can I say all great answers and all correct

Thanks all... :) I can now be confident with this..

NOW anyone know how to take that damn carry handle out of the accessory shoe.. The puzzling part is I know I did it ages ago... I just cant remember how I did it.. My thinking is something has seized a little and I may have to give it an "Ooosh" BUT if I do, I want to make sure its going the right direction...
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#8 Patrick Neary

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Posted 12 February 2006 - 07:13 PM

NOW anyone know how to take that damn carry handle out of the accessory shoe.. The puzzling part is I know I did it ages ago... I just cant remember how I did it.. My thinking is something has seized a little and I may have to give it an "Ooosh" BUT if I do, I want to make sure its going the right direction...


hi again- like i mentioned before, there should be a round knob/plunger-thing at the base of the handle (where it attaches to the shoe) that you pull straight out and hold it out- that releases a pin and you should be able to slide the whole thing out of the shoe (up or down or sideways, it's been awhile- look at the shoe and you will see a stop-pin, just slide the handle out the other direction) It might need some gentle tapping to pop it loose if it's been stuck there for a long time.

If that doesn't work, make your peace with it and use it to hold useful accessories!
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#9 Mark Williams

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Posted 13 February 2006 - 04:57 AM

hi again- like i mentioned before, there should be a round knob/plunger-thing at the base of the handle (where it attaches to the shoe) that you pull straight out and hold it out- that releases a pin and you should be able to slide the whole thing out of the shoe (up or down or sideways, it's been awhile- look at the shoe and you will see a stop-pin, just slide the handle out the other direction) It might need some gentle tapping to pop it loose if it's been stuck there for a long time.

If that doesn't work, make your peace with it and use it to hold useful accessories!


Patrick Got it. It was stuck solid. But I managed to prise it open with a screwdriver. I reckon its where I have been cleaning it and some water got inside.. Anyway soaked the carry handle in oil and wiped away the excess.. Its amazing how well the camera's come up with some cleaning using a toothbrush and being persistant..

T H A N K Y O U
:)
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