Scanning Calibration Targets (Size)

[DJGainer]

Do I really need to get a 4x5 calibration target for velvia, or will a 35mm target suffice? And why not?

-Dave

[Bruce Watson]

Do I really need to get a 4x5 calibration target for velvia, or will a 35mm target suffice?

If you are going to scan 4x5, then you do need the 4x5 target. Different film bases for one thing. Usually the films are slightly different in a number of ways. Which is why there are targets for the individual films.

[DJGainer]

Thanks Bruce. That's what I thought, but while going through the archives I saw one member noted that the size of the target does not matter. I didn't believe it...

[pherold]

It might depend on what brand of target you're talking about. If you happen to be looking into Hutchcolor targets for example, they cut their 35 mm targets from the same stock as their larger targets.


"Note that 35mm and 6x7 cm targets are cut to size from 8x10 inch sheet film. They are NOT created on actual 35mm or 120 versions of these emulsions, but DO produce equivalent results."

http://www.hutchcolor.com/HCT_overview.htm

[DJGainer]

I am talking about the Wolf Faust targets. If I can save the $30 I will.

-Dave

[IanMazursky]

The reason for the cuts from 8x10 film is they are imaged using an LVT film recorder.
It takes 8x10 film and it is extremely accurate.

The 6x7 and 4x5's are also individually measured. Not batch measured like Kodak's.
The Hutch targets are extremely accurate. Don's manual is also a excellent read for those interested in scanner calibration. Its free on his site.
I use the Kodak 4x5 for my Howtek 7500 drum scanner and i am very happy with it. The larger target is very useful as we mostly scan 4x5's.

I personally find the trick to using any target is not to over calibrate. I leave the scanned target a bit wide.
It helps to compensate for slight machine drift and different emulsion types.

[neil poulsen]

I have a Hutchcolor Velvia target, and it didn't work all that well for Ektachrome.

The Hutchcolor site has a document that describes a way to optimize the data from one type of film to get a decent profile for another type of film. But, it involves using a viewing station with variable intensities for both a slide viewer and a print viewer. I checked on line, and these run over $1500.

The Hutchcolor targets are nice and have about 540 patches. This compares favorably to the IT8 Kodak target which has less than 300.

[IanMazursky]

The Ektachrome target is more versatile than the Fuji ones.
I use the Ekta and it works perfectly for all film types.

A viewing booth is nice (I have many) but you can get away with those daylight balanced fluorescents and gray colored walls. Its not perfect but i have seen much worse. It will get you into the ballpark for under $50 (+ the target).