Testing a Hood Before Waisting Film

[Finder]

I would hate to point this out, but vignetting is greater wide open as the hood would have a greater affect on reducing the size of the pupil. Stopping down makes the pupil smaller which can eliminate the vignetting completely.

How sharp the vignetting is has more to do with the placement of the vignetting aperture (and focal length) than the aperture in use - especially since small apertures are unlikely to be vignetted. The sharpness of the vignetting aperture dedends on its relative distance between the effective aperture stop and field stop in the optical system. The closer it gets to an effective field stop, the sharper it is.

 

[Philipp]

I am looking for a hood SMALLER than the currently available vented one, 40.5 thread, (Heavystars is just one of the eBay sellers of it) which is too big to my taste. Finding other standard lens hoods 40.5 thread is indeed quite hard, unless you go for a pricy vintage one.

Hello Ruben,

you might consider this 40.5 hood from hama. It is really designed for 50mm lenses (tested it on my J3), it will cause heavy vignetting on a 35mm or wider lens (tested this on my J12 ). Beeing all black, it does not look very good on a chrome lens, though. You can also use your regular lenscap with this hood, as this one does not change the diameter. Bought it for 7 € new at a photo store.

Greetings,
Philipp

 

[clintock]

If you have a laser pointer, it may be useful to check a hood by shining it from the film side with the lens mounted, shutter open on B, if there is no combination of focus or diaphram settings that let you get the laser spot to strike the inside of the hood, then all should be ok!

 

[ferider]

If you have a laser pointer, it may be useful to check a hood by shining it from the film side with the lens mounted, shutter open on B, if there is no combination of focus or diaphram settings that let you get the laser spot to strike the inside of the hood, then all should be ok!

Now that is smart. Thanks !

 

[edodo]

Philip where did you bought it?

you might consider this 40.5 hood from hama. It is really designed for 50mm lenses (tested it on my J3), it will cause heavy vignetting on a 35mm or wider lens (tested this on my J12 ). Beeing all black, it does not look very good on a chrome lens, though. You can also use your regular lenscap with this hood, as this one does not change the diameter. Bought it for 7 € new at a photo store.

Greetings,
Philipp

 

[ruben]

Hello Ruben,

you might consider this 40.5 hood from hama. It is really designed for 50mm lenses (tested it on my J3), it will cause heavy vignetting on a 35mm or wider lens (tested this on my J12 ). Beeing all black, it does not look very good on a chrome lens, though. You can also use your regular lenscap with this hood, as this one does not change the diameter. Bought it for 7 € new at a photo store.

Greetings,
Philipp

Philipp,
Thanks for the info, this is what I am looking for. But I have no access to them. They aren't sold at eBay. Nevertheless, again, thanks for your effort and pics.

 

[ruben]

Hi

If you are looking at a step-up ring, you are simply further nullifying an already non-existant problem. If you are looking to step-down to a hood smaller than 40.5mm then clearly you deserve all the strife you are likely to get.
To add injury to insult, if the current crop of cylindrical "vented" hoods are like the Hoya and Astron originals, the hood itself only comes in two, or at most three, sizes and the variations made in the thread adapter and the size of the vents. In that case, changing thread size doesn't necessarily fix your problem, and the hoods are probably harder to find anyway. I say this because 40.5 was the most common thread size of the 1950s.
..........

And the "OP" explanation ?

Cheers,
Ruben

 

[Philipp]

Hello Charles,

reading my first posting again I realized the hood is actually from heliopan and not from hama. I bought it from "fotomayr" here in Germany. But I just visited their homepage and they don't have it at the moment. No idea if this is only temporary. Heliopan has two typs of metall lens-hoods: "Kurzblenden" for 50mm lenses and "Teleblenden" for 85mm or longer. You can still find my 40.5mm lenshood on the official heliopan-homepage, so it is still in production and it should be possible to buy it somewhere... Perhaps if you ask a big foto-shop near you, they could order it directly from heliopan?

Greetings,
Philipp

 

[ruben]

Yesterday I found in my closet a compound i built once God knows why, ferfectly fitting as a normal size standard lens hood for an Helios.

It consists in a rubber hood with a 40.5 thread, without the rubber part, and a skylight filter ring for a 49mm lens, without the glass. The filter metal is glued to the plastic ex-rubber hood thread.

I tryied to extend a bit the whole thing by threading another 49 metal without glass, and although it looks fitable and usable, I remained with the above combo for being more compact.

Finito la comedia.

Cheers,
Ruben

PS
It goes without saying that a simple standard rubber hood is too broad for the job. But the good thing is that in order to carry the rubber part, these hoods come with a rather long internal plastic part, or at least the one I have.