[erieguy]

Hi Folks,

Brand new guy here, both to the Forum, to the Pentax Z, and to photography, actually. I hope to get some education here!
I have a Hasselblad V lens that I have mounted on my Z with a Fotodiox adapter. All is fine: I can see the subject through the view finder; I can change the shutter speed via the camera; I get a read out of changes in exposure in the viewfinder and the monitor. However, I do not have a readout in the camera of the aperture setting. All I have is "F - -". The aperture is changing when I use the aperture ring on the lens - I can see the viewfinder darken. I am getting acceptable photos without the aperture readout using the histogram and changing the shutter speed.
Am I doing this correctly? If you have the time to respond, please do so slowly and gently - a babe in the woods here!

[iDon]

That's perfectly all right

[savoche]

Sounds right. There's no way for the lens to report it's aperture to the camera.

Using Av mode should give you fairly consistent exposures with such a lens, though.

And welcome to the forum, and to Pentax!

[erieguy]

Thanks, iDon.

---------- Post added 08-01-14 at 03:17 PM ----------

Sounds right. There's no way for the lens to report it's aperture to the camera.

Using Av mode should give you fairly consistent exposures with such a lens, though.

And welcome to the forum, and to Pentax!

Thanks, savoche! I'll try Av mode.

[iCrop]

The mechanism to actuate the aperture, and report its setting to the camera, was designed for Pentax 645 lenses. Anytime you put a lens not specifically designed for a given camera body (i.e., a Canon lens on a Pentax K mount body, or in this case, a Hasselblad lens on a 645Z) via an adapter, you run the risk of reducing the automatic parts of the lens (focus, aperture) to manual functionality. Anytime the camera can't determine the aperture, it will display "F--" in the viewfinder and LCD. You can use either Av or M modes with this combination.

Please post some photos with that lens, and let us know which one(s) you're using.

[nicemate]

Hello Erieguy, and hello to everyone else as well !

I am looking into shifting to the medium format platform of the 645Z .
A critical element of my decision is the possibility to use my 4 Hasselblad CF-CFi primes, which I have kept albeit not using them for several years.
How do you like using this lens/camera combination so far? is it producing good results, quality-wise?
I understand you don't have autofocus and other automatisms, but I mostly shoot on a tripod or in a studio,
so that wouldn't really be an issue for me.

However, my main doubts regard 2 things in particular:

1) what is the crop ratio (so, for instance, what focal does the Hasselblad 80mm turn into)?

2) and how you should set the camera, should you want to sync the flash with the pc sync of the hasselblad lens, if, for instance, you want to shoot at 1/500th of a second.

Many thanks for your kind attention, and
ciao from Italy !

Pietro

[Adam]

what is the crop ratio (so, for instance, what focal does the Hasselblad 80mm turn into)?

The focal length (of course) stays the same, but your field of view will be cropped by about 1.27x compared to 645 film. This table gives you a handy reference of focal lengths with comparable fields of view:
The Crop Factor Unmasked - Articles and Tips | PentaxForums.com

2) and how you should set the camera, should you want to sync the flash with the pc sync of the hasselblad lens, if, for instance, you want to shoot at 1/500th of a second.

You can read more about high speed sync here:
SMC Pentax 645 LS 75mm F2.8 Reviews - 645 Normal Primes - Pentax Lens Reviews & Lens Database
SMC Pentax 645 LS 135mm F4 Reviews - 645 Telephoto Primes - Pentax Lens Reviews & Lens Database

I don't think you'll be able to sync the flash beyond the standard 1/180s unless you have a Pentax leaf shutter lens that the camera recognizes, but I could be wrong.

Adam
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[The Madshutter]

Hello and welcome Erieguy,

as has been said, there is no way for the camera to know what aperture you are shooting at, therefore it will display F--. More, whichever mode you'll use, the aperture mechanism is not automated - your viewfinder is going to get darker and darker the smaller an aperture you'll use, which may turn into a problem if you plan to shoot in low light.

Ciao Pietro and welcome,

about your question, your lenses (whichever brand you'll use) will have a crop factor of about 0.8 (0.78 to be exact, if I am not wrong) compared to 35mm. About flash sync speed, since you will be using the 645z's shutter and not the shutter in the Hassy lenses, you'll get the sync speed that your camera / flash combination will allow you: 1/180 native, but you can get higher with some flashes.

Hope this helps, and welcome again to you both! Best,

Vieri

[nicemate]

Hello Adam, Hello Vieri!
and thanks to everyone for the answers.

It totally makes sense that I won't be able to fire the Hasselblad lens shutter
on the Pentax camera, now that I think about it!

In theory you could fire the Pentax on bulb and then fire the lens shutter somehow, but I assume
that is quite complicated.

However, chances are that, if the flash duration is quite slow, you might be able to get a clean
shot (with identical exposure top to bottom, without any "tails") with a higher speed. Although
manufacturers today tend to produce flashes with extremely short flash durations.

At the end of the day it is probably much better to use Pentax leaf shutter lens.

cheers,
Pietro

[algrove]

I am new to the 645Z since January and I use my old Hassy CF V lenses on thye 645Z without issue. I set camera to M adjust speed on camera and f stop on lens and look at exposure on LCD. No issues. What really pleasantly surprised me on the first image shot was that the camera beeped and showed a red square where I was in focus with the Hassy lens. Couldn't be happier.

[desertdiver]

..... What really pleasantly surprised me on the first image shot was that the camera beeped and showed a red square where I was in focus with the Hassy lens. Couldn't be happier.

That was a welcome surprise for me as well when I started using Hasselblad V-System lenses on my 645D.

I did test a few Hasselblad lenses on a 645D a while back. Just in case someone is interested, here is the link:

https://www.pentaxforums.com/forums/48-pentax-medium-format/254060-645d-hasse...ml#post2747221

All the best,
Udo

[The Madshutter]

That was a welcome surprise for me as well when I started using Hasselblad V-System lenses on my 645D.

I did test a few Hasselblad lenses on a 645D a while back. Just in case someone is interested, here is the link:

https://www.pentaxforums.com/forums/48-pentax-medium-format/254060-645d-hasse...ml#post2747221

All the best,
Udo

Indeed having focus confirmation with any old lens (Pentax 645 MP, Pentax 67, Hassy) is a great feature - and it works pretty well, too, is more than precise enough to get you in the ballpark. Udo, once more great sum up on the Hassy lenses, thank you for doing it and for reminding us of the post

Best,

Vieri

[nicemate]

It would be great to know if anyone has been able to sync flash at a speed higher than 1/125th, and with a clean shot ! (by clean I mean without dark "trails")

[bull drinkwater]

i'm in the same situation using canon fd lenses on my sony alphas. I've established my operation system, and now it's a piece of cake.

[bileu]

Guys .. any opinions on how the 80/2.8 and 150/4 perform on modern pentax MF sensors? I have an opportunity to grab hold of older versions T* 80 and 150 lenses along with a 500CM body very cheap. There is no support system here locally to shoot MF film but I'll be able to use the lenses on my 645Z. Any experiences or opinions and comparisons with Pentax lenses would be great.