Hasselblad 35-90 lens: aperture blades visible when shooting wide open

[epines]

For anyone who owns the HCD 35-90 lens, I'm wondering if you have noticed this: I just got a used one, and I'm noticing that, at all focal lengths but 90mm, when I shoot wide open, the aperture blades don't open all the way (i.e., aren't completely retracted and out of sight). For example, at 35mm, at f/4, when I shoot and look into the front element, I can see the aperture blades slightly contracted, as if it's closing down slightly. And at 50mm f/4.5. And so on, through all focal lengths but 90mm. At 90mm (f/5.6), you can't see them at all.

Is this normal? Does it happen with your copy of the lens?

thanks
ethan

[Joe Towner]

I've never seen this - I hope you purchased it from a dealer or such as it may need to be repaired.

[Joe Towner]

Let me reply again post-coffee.  Does it show on your images?  That 95mm front is huge, and anything you see would be magnified right?  How does the lens react when you stop it down?  I'll get one in hand soon and let you know what I see, but I have been a little too focused looking thru the other direction.

[Go Go]

You may be seeing the shutter?
Certainly somebody here will have an explanation though.

[epines]

Joe Towner: I'll be doing a comparison when I get home to my primes, to see if f4.5 on the zoom matches f4.5 on the primes, for example. When you stop it down, same thing happens. You can see the aperture blades slightly when the camera is set to wide open.

Go Go: definitely not seeing the shutter. If I take, say, an 8-second exposure, the shutter is open, and I can see the aperture blades slightly.

[epines]

Here's an update: I got back home to L.A. and went to Samy's, where I compared my 35-90 to their demo 35-90. And their lens does it too. We tried both lenses on two different bodies. All did the same thing. At focal lengths below, say, 80mm, with the aperture wide open, you can see the aperture blades slightly when shooting or when stopped down. They contract slightly. If you own one, I can pretty much guarantee that yours does it too. The veteran Hasselblad repair guy there confirmed this. Guess it has something to do with the zoom's construction.

I shot a comparison to my 50mm prime, and both produced identical histograms at all apertures. (Notwithstanding a little more vignetting in the 35-90 when wide open.)

best,
ethan


 

[JV]

I shot a comparison to my 50mm prime, and both produced identical histograms at all apertures. (Notwithstanding a little more vignetting in the 35-90 when wide open.)

The 50mm-II or the first version?  Thanks, Joris.

[epines]

First version.