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Focus stacking with mechanical lens release

Focus stacking with Helicon etc is a great tool and works wonderfully with an electronic cable release. Can one also use focus stacking on a view camera such as the Linhof Techno that requires a mechanical cable release, or do the small movements to the lens that might occur due to the releasing of the shutter with the moving cable inner and then resetting the lens render focus stacking not so accurate?
 
I've found that for close up work using a focusing rail works best. Depending on the lens length focusing with a helical will affect the image size (for example on a 90mm I can see the image get larger and smaller as I change focus). In all these cases, photoshop is able to compensate suitably.

There's a middle ground (about 1/2 to 2 1/2 metres on the 90) that is particularly difficult as it's too long for the focusing rail, yet the DoF is still small requiring many shots, and focus increments cause quite a large change in the image size.

I've never tried focus stacking with an electronic shutter, in fact I've had most success using a view camera and changing focus with the back, as the back moves away it should make the image smaller which somewhat offsets the magnifcation caused by increasing the distance between the lens and back, so the problems are still there - the images gets bigger - but less pronounced when using the back.
 

baxter

New member
The techno is a very rigid platform and I cannot see that cocking and releasing the shutter would incur movements in lens position unless you were very heavy handed or using a tripod with inadequate stability.

I can see that the refocusing procedure would be very fiddly and the time delay would probably produce differences in lighting unless in a studio. There would also be the need to reshoot LCC frames making the process longer still.

I am puzzled as you why you envisage the need for Helicon with a Techno. Correct use of it's view camera movements should ensure that focus is properly controlled.

Currently I am contemplating the purchase of a Techno for my DB having found focus stacking unable to handle coastal scenes where wave and cloud movement prevent me combining several frames using my 645DF.

I sold my Ebony 45SU as I understood that it was inferior to the Techno for use with a DB, essentially this was a rigidity issue. I dearly miss having camera movements to control perspective and focus.
 

malmac

Member
Hello fellow forum members

I have just moved into MF with a Phase One system (645DF) and also a Cambo WDS ( for which I currently only own a S/K 35mm lens).

I mostly shoot landscape and want to improve my control over DOF and have been thinking about getting Helicon Focus - but your comments re a focus rail - make me realise that I need to know a good deal more before I throw more dollars at improving my image quality.

I would appreciate any information on the make and model rails that would be well suited to landscape photography and focus stacking with Helicon Focus. By the way I have held off upgrading my tripod head pending a betting understanding of the focus stacking process.

Thanks in advance.


Mal
 
Baxter, I think we are coming from similar experiences. My move is from an Ebony RW45, via Canon 5dMkii. There are situations in landscape where view camera movements still can't deliver sharp focus from close to far - for instance in a forest, where Helicon could do the trick (on a windless day!). For moving subject matter, such as a seascape, Helicon is of very limited use and movements are all we have. But a mfdb with a good view camera and lens and Helicon, bearing in mind the difficulties you raise, could be spectacular.

Thanks for your thoughts on stability, I reckon you are right.
 
For longer distance landscape work you would will have to re-focus the camera, for macro work you can also re-focus the camera, but as you gain experience you might find a rail preferable.

There is absolutely no problem with using a mechanical shutter for focus stacking. Both CS4/5 and Helicon compensate for small movements and also for the change in size of the image during re-focusing.

The best thing I could possibly recommend is to try it with what you have now to get a feel for it.

If you do do macro stuff then here is an example using a focusing rail
 

baxter

New member
I agree that there are occasions when this would work and I've been grateful for the ability to work with Helicon and the 645DF. The attached is such an example, camera movements just couldn't handle the complexity of the 3D nature of this scene.

However there can be a fair bit of editing to do in Helicon and this is relatively clumsy. Sometimes it just doesn't seem to grasp what is needed. As such I only use Helicon if absolutely necessary.

I think that the focussing rail would be helpful in composition as it's necessary to be a little loose if only use camera to do the focus stepping. front to back in the attached image was about 40-50cm if I remember correctly.
 
Having not yet taken the plunge I'm actually leaning towards the !Q180 on an Arca Swiss RM3DI - no rail here so I'd be confined to changing focus. Does this sound reasonable?
 

Don Libby

Well-known member
I've shot several images for focus stacking using my WRS without any major trouble or problems. While I still have a focusing rail I have stopped using it for the most part as I've found changing the focus through the lens to be more than adequate.

You should have little problems so long as you have a very steady tripod and minimize vibrations. Shoot, refocus, re-cock, shoot, refocus, re-cock, shoot ....

Don
 
Rob,
Do you have the opportunity to rent the gear or go to a dealer and try it? I think you'd be better off with someone that could walk you through it.

Paul
 

gurtch

Well-known member
I just made a series of focus stack tests using a 645D, 35mm A lens, 1/800 sec at f8, using Helicon Focus. I focused on the nearest object visible in the viewfinder (about 5 ft away), then made 6 more exposures, the last of which was infinity (as marked on the lens)- the results look very promising for landscape/seascape work. I just received a 10 stop ND filter to use making seascapes, so the water will blur. Has anyone done focus stacking of moving objects, such as water? It might give a similar effect?
Thanks
Dave
 

Bob

Administrator
Staff member
It works great for me as long as I don't kick one of the tripod legs
-bob
 

rga

Member
One issue to consider when deciding on changing the lens focus vs a focusing rail is if you're using tilt. With tilt, I don't think a rail will work to put objects above and below your new plane of focus into focus. You will need to use the focus ring on your lens.

For another technique for focus blending not requiring Helicon software take a look at this process used by Paul Roark:
http://www.paulroark.com/BW-Info/Dual-Focus-Focus-Stacking.pdf
 
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