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I am thinking abut buying a lens that does not come with a shutter and using the shutter from another lens. How much of a problem is it if the shutter is f8 and the lens f5.6? It seems to me that I would loose the ability to open the lens completely so I it would be like using an f8 lens. Is this correct and are there other issues that I am not seeing? Thanks
LensA = the one in shutter
LensB = the other one
LensA / f8 = entrance pupil size in millimeters (EP)
LensB / EP = your actual aperture when set to f8
Assuming both lenses actually fit in the same shutter, this would be how you calculated the f/stop, and most likely if it's, say, a 90mm f/8 lens and a 135mm f/5.6 lens, it'll just be a stop off (when f/8 is set, it'll be close to f/5.6). Almost certainly, your aperture will not be f/8 when set as such for the new lens. Frankly there usually isn't much economy or reason to buy a lens without shutter and try to double-up on one shutter.
Google search, this question comes up all the time.
Thanks. I will check it on Google.
Before taking the plunge in the Internet jungle, do not forget that our forum members have written reference articles where the subject is addressed !
Thanks again, Dan !
http://www.galerie-photo.com/1-lens-...omm.html#htoc4
Might help if you posted what lenses you are looking at, too.
What lens, and what shutter?Quote:
Originally Posted by DEC3
The reason I ask is because this is one of those things in the, "it depends," category. Lenses that normally come without a shutter are called "barrel" lenses, because it's just a hollow tube with glass at either end. Some can be easily mounted in a shutter, and some require a machinist to do some work. Sometimes someone buys an antique lens, and has it mounted in a contemporary shutter. That's done quite often.
Another thing is that some lenses have spacers between the lens and the shutter. Without that spacer, the lens won't perform correctly, and it may need to be sent to the factory to be put into specification.
If the lens elements in question are in a common focal length, then just buy a complete lens. There are lots of lenses in common focal lengths for reasonable prices.
The numbers on an aperture scale only have meaning for the focal length they were intended for.
Thus if you have a Copal 1 shutter made for a 210mm Symmar for instance. Close the aperture to f8 2/3 iow f10. Measure the hole with a ruler. It'll be 21mm. 10X21 = 210. So if you stick a 90mm f8 lens in that shutter, the same 21mm hole would be f4.2 if it had it, which it wouldn't.
What you CAN do though is stick the 90mm f8 cells in the 210 Copal and close down to where you first see the blades. That's a known, right? f8. With modern copals everything is equidistant, so once you know where f8 is on the scale, you can figure out the rest.
I use wrong shutters . . . A LOT. But that's just me. I'd also drive a car coast to coast with a coat hanger throttle linkage. That stuff just doesn't bother me.
Thanks for all the input. This was my first experience with this forum and I can see that it will be very helpful going forward. From the responses I see that it is best not to buy the lens in question as similar ones are available complete with the shutter. Thanks again.
Indeed. If the lens you want [or another that's genuinely equivalent] is readily available in a shutter, just buying it mounted in shutter may save you a lot of hassles down the track...
if two lenses are made to fit the same shutter then swapping over is easy but sorting out aperture scales can be a fiddle
and a barrel mount lens can be fitted to a suitable shutter but then you're usually getting into specialist territory
Just to make things more confusing, there are some large format cameras with their own shutter built in.
If you happen to get one of these cameras, you can often find some very interesting lenses for extremely good prices that will be fully functional.
In the future, with a little experience you may not even need a shutter of any type.
All photographers used to do was cover the lens with a hat or anything that blocked the light.
I have never met any, but there are a few of them on this board.