Film holders and film flatness

[olwick]

Hi,

Is there any one brand/type of 4x5 film holder that holds the film more perfectly flat than others?

I was reading Barry Thornton's Edge of Darkness, which prompted this question. It makes sense that there would have to be a small amount of "slop" in the film plane of holders due to having to be able to slide the film in and out, which he says can affect consistent sharpness across the plane.

Thanks,

Mark

[Daniel Stone]

I haven't had a problem so far with 4x5 or 8x10 holders, no matter the brand. But then again, I DON'T shoot wide-open most of the time.

for 4x5's I have plastic holders, and 8x10 holders are the kodak/agfa wooden ones. Probably 50yrs old +, but still work like new.

-Dan

[Bill_1856]

There are vacuum holders out there, used mainly for scientific work before digital took over, but basically I think you'd be swatting at mosquitoes.

[memorris]

Some investigation by a local photographer a couple of years ago had Toyo as the most consistent in position and flatness.

[Brian Stein]

Yes there will be some bow in the film, the bow being larger the larger the film sheet. There is no way apart from a vacuum back or similar or moving to glass plates (I recall someone using wedges to jam the sheet of an ULF film into a home made back) to overcome this. Against this is the general requirement for less tight tolerances the bigger the film because of lower enlargement factors, and the tendency to use smaller apertures.
Practically, having a bunch of holders from different makers and different eras I cant say that there is any detectable difference in the "slop" in the film, nor in the sharpness of the end result between them in the sizes I use (45 57).

[Steve Hamley]

I've found there's very little if any bow in 7 mil film in 4x5 holders. Of the 4x5 holders, Riteways I've measured have less space between the film rails and the platen, so there's less space for the film to move back and forth. I posted the measurements in a thread a while back.

On 8x10, I like Toyos because they have extra "fingers" in the end of the holder that the film slides under.

Cheers, Steve

[Steve Gledhill]

As far as I can tell my film is always held flat in my Lisco 5x4 holders - EXCEPT - there is one set of conditions when the film may not be flat - see this post from a while back about photography in cold weather. My post was really about film moving laterally in the holder but I guess it could also 'pop' from flat to not flat with an abrupt temperature change.

[Brian Ellis]

Somebody published results of an exhaustive test of about 10 different film holders in View Camera magazine or maybe it was Photo Techniques some years ago. None held the film perfectly flat. IIRC the winner actually was an older wood holder and I think a Grafmatic did pretty well too. But none of them were very close to perfect.

This is one of those things that always comes to mind when I hear or read of people getting excited because the front standard and rear standard on their cameras are out of parallel by .2mm or that their bubble level is off by .1mm. These things we use aren't precisions instruments and getting worked up over some insignificant deviation from perfection is a waste of time and energy IMHO.

[SamReeves]

Yea, I don't think there is too much to worry about flatness in your average plastic holder. I've used the Lisco's for 10 years, and haven't had any issues. It's all about the loading!

[Jack Dahlgren]

If I look at all the holders I have that have light leaks, they are all fidelity/lisco. I don't like the plastic holders for that reason. But for film flatness, you probably won't see much difference between holders (other than normal variation) unless you use a vacuum back or glass plates. There are some Linhof holders which clamp down on the film, but I hear that they are troublesome to use and expensive. I have not tried them.

Do you currently have a problem with film flatness that you are trying to solve? Or is this "just in case"?