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Focusing and DOF

V

visionaryelitist

New Member
Hi. I have just acquired my first MF camera, a 503CX with CF Planar T 2.8/80. Looking down on the focusing screen is amazing in itself although it will take some getting used to everything being back to front! I've only shot a few exposures on it so far but am finding focusing, even with the magnifyer, a little odd. Coming from only ever using 35mm/FF DSLR where focusing manually was relatively simple-its either sharp or its not. With the focus ring being that much more precise, i'm second guessing myself all the time. I guess its not too much of a problem with smaller apertures and/or further focusing distances but wide open and 3 feet away for example, I dont know just how critical it is. I am aware of other screens for it but which would you recommend to aid my aging eyes!

On a seperate but related issue, DOF. Over the years i've come to instinctively know what aperture to plump for, depending on my vision for the shot and focal length. Now it seems I have no idea. ok, so i get that larger format equals less DOF but in the field, how do i translate this to my brain? For my landscapes I tended only ever to stop down to f/16 on my canon optics due to diffraction and even then over time lent more toward f/11 if i could. Is there a similar logic to zeiss lenses or does diffraction not exist in this premium grade world?? Hopefully down the line I will add a wide angle or two to my CZ arsenal but for now am stuck with the good old standard 80mm. Is it as sharp wide open as at f/4??

This is only my first day with my new toy but already i feel i have a thousand questions! Please feel free to leave me some thoughts.
 
Hi, I followed a similiar path into the Hasselblad system and experienced the same technical points when I started using the equipment.

For focussing I bought a grid screen with a split image focussing aid and a Prism finder. This has helped both my focussing and the horizontal alignment of the image as found my first pictures has a distinct right hand tilt when used handheld.

Depth of field was a revelation in MF especially as I use the FE series of lenses that are typically one stop brighter than the CF range of lenses. I developed my own rule of thumb which I estimated to be approximately 1 stop more depth of compared to 35mm lenses.

For example: F2.8 = F2.0, F4.0 = F2.8 etc. This is only an approximate guide and of course needs to take into account the focal length of the lens as well.

Regards

Kevin
 
Thanks Kevin. Good to see i'm not alone.

Apart from ebay, where's the best place to look for accessories? I've been looking at all the different prisms and its quite confusing at first. The meterd ones are probably out due to the ridiculous cost but maybe a PM90 might be nice?

Am i right in thinking the FE's can only be used with the 200 series?
 
Hi visionaryelitist,

Firstly you are correct that the FE Lenses (or F Lenses) can only be used on a Hasselblad with a Focal Plane shutter (as in a 35mm SLR). The cameras are from the 2000 and 200 series and are the most versatile as you can use the Focal Plane shutter as well as the central shutter found in C, CF, CFE and CFi lenses. The 200 series featured integrated metering (apart from the 201F) with Aperture Priority exposure automation.

For accessories you can look at this very site under the Classified section as a starting point. Polypal usually has a good selection of items for sale.

I have been able to get some superb equipment on eBay for a fraction of the original prices - a pity as people turn to digital they are giving up some of the best photo gear ever made.

I would personally recommended a 45 degree Prism unless you shoot most of your work on a tripod at eye level. I have a PM45 and a PM5 - the PM45 has adjustable dioptre correction, 2.5x magnification and a nice large finder eyepiece. I have moved to using the PM45 as it is a more compact finder and offers 3x magnification.

You need to sometimes wait a bit for eBay bargains to come along. I have seen some excellent metered Prisms go for very low prices.

Regards

Kevin
 
Besides the fact that stopping down gives more DOF there is virtually no need to stop down to improve IQ of the Zeiss lenses.
The IQ of these wonderful lenses is hardly improved by stopping down.

DOF is a function of the magnification which is larger with MF resulting in less DOF at the same F number and what is considered as comparable focal length.


Vic.
 
Kevin - I'm still a little confused about all the available prisms. I've had a mooch on said auction site and the prices do seem to vary wildly, as do the model numbers! seems there are lots of versions but not a huge amount of info to accompany them. You mention your PM5 and PM45 but refer to the PM45 for both comparisons......could you clarify please?

Vic - granted, there will be less DOF, but what I meant is how to visualise this when shooting. I guess it's something over time I will just be accustomed to. Trial and error.
 
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